Training curriculum This course on Good agricultural practices for ware potato production in Rwanda comprises 4 modules and 20 themes, as outlined below: Module 1: Introduction to the potato crop Theme 1. Importance of the potato crop Theme 2. Understanding the crop cycle of potato Module 2: Soil, crop and water management Theme 3. Land selection and crop rotation Theme 4. Land preparation Theme 5. Application of manure, compost and mineral fertilisers Theme 6. Planting techniques Theme 7. Weeding and hilling Theme 8. Irrigation Theme 9. Intercropping potatoes Module 3: Pest and disease management Theme 10. The disease triangle Theme 11. Control of late blight Theme 12. Control of bacterial wilt Theme 13. Control of soft rot (or blackleg) Theme 14. Control of viral diseases Theme 15. Control of potato tuber moth Theme 16. Control of nematodes Theme 17. Safe use of pesticides Module 4: Post maturity practices Theme 18. Harvesting Theme 19. Sorting and grading tubers for the market Good agricultural Theme 20. Storage of ware potatoes practices for ware potato The sequence of modules and themes follows a certain logic as per the growth and development cycle of the potato crop. Therefore, it is recommended to follow the same sequence during training sessions. This guide can be used either for the training of trainers (the training of potential trainers of producers) or directly for the production in Rwanda training of producers. For each theme, the trainer-of-trainers or the trainer should allocate a minimum of 15 minutes for presentation and 10 minutes for questions and answers. In total, the course requires a minimum of 8 hours to be completed, equivalent to a 2-day training workshop for the trainers or 4 training sessions of 2 hours for the producers. In a bid to gauge the impact made in training at any level, trainers are encouraged to assess participants’ knowledge through a written test before and after the training using the same Trainer Guide questionnaire. A test sample is provided in appendices. It is recommended that the trainers pass the evaluation test with a score of at least 12/20. Training materials Producer handout This course is designed to be a complete set of training materials for easy or scale out. The training materials This is a pocket-size handbook that the trained producers use. It is recommended to distribute the manual after are modular to facilitate use by various stakeholders focusing on different aspects of crop production. Four completion of the training. If the acquisition of the manual takes place before the training, it may provide types of tools are provided to facilitate the training of trainers and then cascade down the training to participants with an excuse to skip training sessions or for them to lose focus during training. In this regard, the producers. Those materials are the following: Producer handout could be considered as an incentive for completion of the training by producers. 1) Trainer Guide Demo Guide 2) Trainer Visual Aid This guide is a complementary support tool to the training materials. Therefore, it is not meant to be used 3) Producer handout alone. It helps the trainer to organize and facilitate hands-on training in the field, to complement the more 4) Demo Guide theoretical training sessions elaborated in the Trainer Guide. It comprises three demonstration protocols: (i) Trainer Guide crop husbandry, (ii) positive selection and (iii) small plot technique. For each demo, the guide provides The Trainer Guide is the master document printed in A4 format. It comprises three major parts: responses to the following questions: What, Why, When, For how long, With what and How. The How includes both text and images in a bid to clarify the different steps required in each training session. When planning a (i) the course overview, (ii) the 4 training modules with 20 themes also found in the Producer handout, and (iii) demo training session, the trainer should consider four successive steps: (i) Introduction to (or brief refresher the appendices. The course overview presents the training curriculum and all materials to be used. The second explanation on) the topic; (ii) the practice of the demo as per the demo guide; (iii) a session of questions and part of the guide consists of the training modules, alongside with instructions for trainers. In the last part answers among participants; and then (iv) the way forward for the next training session. (appendices), the Guide provides suggested questions and take-home messages per theme as outlined in the Trainer Visual Aid, as well as a test sample for pre- and post-training knowledge assessment. Visual Aid The Trainer Visual Aid is a didactic tool which helps the trainer to train participants. The front page contains an image which depicts the topic. That is the image participants see. The rear page is reserved for the trainer, and it includes four components for each of the 20 themes: (i) a small format of the front-page image; (ii) a brief summary of the theory in bullet points in which keywords are provided in bold, (iii) three guiding questions, and (iv) a take-home message. The small image helps the trainers remain focused on the topic. Brainstorming on the image can be done using the front page one. In his/her introduction to the topic, the trainer may ask participants to critically look at the image and describe what they understand from it. For each figure, three questions are suggested to recap and confirm whether the participants understood the topic or not. The trainer closes the topic with a take-home message. Training curriculum This course on Good agricultural practices for ware potato production in Rwanda comprises 4 modules and 20 themes, as outlined below: Module 1: Introduction to the potato crop Theme 1. Importance of the potato crop Theme 2. Understanding the crop cycle of potato Module 2: Soil, crop and water management Published by: International Potato Center (CIP) Theme 3. Land selection and crop rotation Registered offices: Avenida La Molina 1895, La Molina, Apartado Postal 1558, Lima, Peru Theme 4. Land preparation E cip@cgiar.org Theme 5. Application of manure, compost and mineral fertilisers I cipotato.org Theme 6. Planting techniques Theme 7. Weeding and hilling Correct citation: CIP (2021). Good agricultural practices for ware potato production in Rwanda • Theme 8. Irrigation Trainer Guide. International Potato Center (CIP), Lima, Peru. Theme 9. Intercropping potatoes Acknowledgements: This manual was developed through a collaboration between the International Potato Center (CIP), Module 3: Pest and disease management Rwanda Agriculture and Animal Resources Development Board (RAB) and Agriterra. Theme 10. The disease triangle This manual is published as derivative work of the manual ‘Good Agricultural Practices for Ware Theme 11. Control of late blight Potato Production in Cameroon – Trainer guide’ published by the German Federal Ministry for Theme 12. Control of bacterial wilt Economic Cooperation and Development (BMZ) and available at Theme 13. Control of soft rot (or blackleg) https://hdl.handle.net/10568/108468 under Creative Commons Attribution 4.0 International license Theme 14. Control of viral diseases (CC BY 4.0). Theme 15. Control of potato tuber moth We acknowledge the contribution of representatives from Imbaraga Farmers Organisation, Delphy, Theme 16. Control of nematodes SPF-Ikigega, Rwandan Potato Stakeholders Platform, INES-Ruhengeri, UR-CAVM, Horizon-Sopyrwa, Theme 17. Safe use of pesticides Musanze District, Holland Greentech, Hollanda Fair Foods, HoReCo Rwanda, Potato Unions in Musanze, Nyabihu and Rubavu Districts and CODEPO Potato Farmers Cooperatives supported by Module 4: Post maturity practices Agriterra in Rwanda. Theme 18. Harvesting The development of this manual has been commissioned by Agriterra. Theme 19. Sorting and grading tubers for the market Place and date of publication: Theme 20. Storage of ware potatoes Kigali / July 2021 The sequence of modules and themes follows a certain logic as per the growth and development cycle of the potato crop. Therefore, it is recommended to follow the same sequence during training sessions. This guide can be used either for the training of trainers (the training of potential trainers of producers) or directly for the training of producers. For each theme, the trainer-of-trainers or the trainer should allocate a minimum of 15 minutes for presentation and 10 minutes for questions and answers. In total, the course requires a minimum of 8 hours to be completed, equivalent to a 2-day training workshop for the trainers or 4 training sessions of 2 hours for the producers. In a bid to gauge the impact made in training at any level, trainers are encouraged to assess participants’ knowledge through a written test before and after the training using the same questionnaire. A test sample is provided in appendices. It is recommended that the trainers pass the evaluation test with a score of at least 12/20. Training materials Producer handout This course is designed to be a complete set of training materials for easy or scale out. The training materials This is a pocket-size handbook that the trained producers use. It is recommended to distribute the manual after are modular to facilitate use by various stakeholders focusing on different aspects of crop production. Four completion of the training. If the acquisition of the manual takes place before the training, it may provide types of tools are provided to facilitate the training of trainers and then cascade down the training to participants with an excuse to skip training sessions or for them to lose focus during training. In this regard, the producers. Those materials are the following: Producer handout could be considered as an incentive for completion of the training by producers. 1) Trainer Guide Demo Guide 2) Trainer Visual Aid This guide is a complementary support tool to the training materials. Therefore, it is not meant to be used 3) Producer handout alone. It helps the trainer to organize and facilitate hands-on training in the field, to complement the more 4) Demo Guide theoretical training sessions elaborated in the Trainer Guide. It comprises three demonstration protocols: (i) Trainer Guide crop husbandry, (ii) positive selection and (iii) small plot technique. For each demo, the guide provides The Trainer Guide is the master document printed in A4 format. It comprises three major parts: responses to the following questions: What, Why, When, For how long, With what and How. The How includes both text and images in a bid to clarify the different steps required in each training session. When planning a (i) the course overview, (ii) the 4 training modules with 20 themes also found in the Producer handout, and (iii) demo training session, the trainer should consider four successive steps: (i) Introduction to (or brief refresher the appendices. The course overview presents the training curriculum and all materials to be used. The second explanation on) the topic; (ii) the practice of the demo as per the demo guide; (iii) a session of questions and part of the guide consists of the training modules, alongside with instructions for trainers. In the last part answers among participants; and then (iv) the way forward for the next training session. (appendices), the Guide provides suggested questions and take-home messages per theme as outlined in the Trainer Visual Aid, as well as a test sample for pre- and post-training knowledge assessment. Visual Aid The Trainer Visual Aid is a didactic tool which helps the trainer to train participants. The front page contains an image which depicts the topic. That is the image participants see. The rear page is reserved for the trainer, and it includes four components for each of the 20 themes: (i) a small format of the front-page image; (ii) a brief summary of the theory in bullet points in which keywords are provided in bold, (iii) three guiding questions, and (iv) a take-home message. The small image helps the trainers remain focused on the topic. Brainstorming on the image can be done using the front page one. In his/her introduction to the topic, the trainer may ask participants to critically look at the image and describe what they understand from it. For each figure, three questions are suggested to recap and confirm whether the participants understood the topic or not. The trainer closes the topic with a take-home message. Content Course overview 3 Training curriculum Training curriculum 3 This course on Good agricultural practices for ware potato production in Rwanda comprises 4 modules and 20 Training materials 4 themes, as outlined below: Trainer Guide 4 Visual Aid 4 Module 1: Introduction to the potato crop Producer handout 5 Theme 1. Importance of the potato crop Demo Guide 5 Theme 2. Understanding the crop cycle of potato Introduction to the potato crop 6 Theme 1. Importance of the potato crop 6 Module 2: Soil, crop and water management Theme 2. Understanding the crop cycle of potato 7 Theme 3. Land selection and crop rotation Soil, crop and water management 9 Theme 4. Land preparation Theme 5. Application of manure, compost and mineral fertilisers Theme 3. Land selection and crop rotation 9 Theme 6. Planting techniques Theme 4. Land preparation 10 Theme 7. Weeding and hilling Theme 5. Application of manure, compost and mineral fertilizers 11 Theme 8. Irrigation Theme 6. Planting techniques 12 Theme 9. Intercropping potatoes Theme 7. Weeding and hilling 14 Theme 8. Irrigation 15 Module 3: Pest and disease management Theme 9. Intercropping potatoes 16 Theme 10. The disease triangle Pest and disease management 17 Theme 11. Control of late blight Theme 10. The disease triangle 17 Theme 12. Control of bacterial wilt Theme 11. Control of late blight 18 Theme 13. Control of soft rot (or blackleg) Theme 12. Control of bacterial wilt 20 Theme 14. Control of viral diseases Theme 13. Control of soft rot (or blackleg) 21 Theme 15. Control of potato tuber moth Theme 14. Control of viral diseases 22 Theme 16. Control of nematodes Theme 15. Control of potato tuber moth 23 Theme 17. Safe use of pesticides Theme 16. Control of nematodes 24 Theme 17. Safe use of pesticides 25 Module 4: Post maturity practices Post-maturity practices 26 Theme 18. Harvesting Theme 18. Harvesting 26 Theme 19. Sorting and grading tubers for the market Theme 19. Sorting and grading tubers for the market 27 Theme 20. Storage of ware potatoes Theme 20. Storage of ware potatoes 28 APPENDICES 30 The sequence of modules and themes follows a certain logic as per the growth and development cycle of the potato crop. Therefore, it is recommended to follow the same sequence during training sessions. This guide Appendix 1. Guiding questions and take-home messages per figure 31 can be used either for the training of trainers (the training of potential trainers of producers) or directly for the Appendix 2. Test sample for pre- and post-training knowledge assessment 35 training of producers. For each theme, the trainer-of-trainers or the trainer should allocate a minimum of 15 minutes for presentation and 10 minutes for questions and answers. In total, the course requires a minimum of 8 hours to be completed, equivalent to a 2-day training workshop for the trainers or 4 training sessions of 2 hours for the producers. In a bid to gauge the impact made in training at any level, trainers are encouraged to assess participants’ knowledge through a written test before and after the training using the same questionnaire. A test sample is provided in appendices. It is recommended that the trainers pass the evaluation test with a score of at least 12/20. 2 Training materials Producer handout This course is designed to be a complete set of training materials for easy or scale out. The training materials This is a pocket-size handbook that the trained producers use. It is recommended to distribute the manual after are modular to facilitate use by various stakeholders focusing on different aspects of crop production. Four completion of the training. If the acquisition of the manual takes place before the training, it may provide types of tools are provided to facilitate the training of trainers and then cascade down the training to participants with an excuse to skip training sessions or for them to lose focus during training. In this regard, the producers. Those materials are the following: Producer handout could be considered as an incentive for completion of the training by producers. 1) Trainer Guide Demo Guide 2) Trainer Visual Aid This guide is a complementary support tool to the training materials. Therefore, it is not meant to be used 3) Producer handout alone. It helps the trainer to organize and facilitate hands-on training in the field, to complement the more 4) Demo Guide theoretical training sessions elaborated in the Trainer Guide. It comprises three demonstration protocols: (i) Trainer Guide crop husbandry, (ii) positive selection and (iii) small plot technique. For each demo, the guide provides The Trainer Guide is the master document printed in A4 format. It comprises three major parts: responses to the following questions: What, Why, When, For how long, With what and How. The How includes both text and images in a bid to clarify the different steps required in each training session. When planning a (i) the course overview, (ii) the 4 training modules with 20 themes also found in the Producer handout, and (iii) demo training session, the trainer should consider four successive steps: (i) Introduction to (or brief refresher the appendices. The course overview presents the training curriculum and all materials to be used. The second explanation on) the topic; (ii) the practice of the demo as per the demo guide; (iii) a session of questions and part of the guide consists of the training modules, alongside with instructions for trainers. In the last part answers among participants; and then (iv) the way forward for the next training session. (appendices), the Guide provides suggested questions and take-home messages per theme as outlined in the Trainer Visual Aid, as well as a test sample for pre- and post-training knowledge assessment. Visual Aid The Trainer Visual Aid is a didactic tool which helps the trainer to train participants. The front page contains an image which depicts the topic. That is the image participants see. The rear page is reserved for the trainer, and it includes four components for each of the 20 themes: (i) a small format of the front-page image; (ii) a brief summary of the theory in bullet points in which keywords are provided in bold, (iii) three guiding questions, and (iv) a take-home message. The small image helps the trainers remain focused on the topic. Brainstorming on the image can be done using the front page one. In his/her introduction to the topic, the trainer may ask participants to critically look at the image and describe what they understand from it. For each figure, three questions are suggested to recap and confirm whether the participants understood the topic or not. The trainer closes the topic with a take-home message. Course overview Training curriculum This course on Good agricultural practices for ware potato production in Rwanda comprises 4 modules and 20 themes, as outlined below: Module 1: Introduction to the potato crop Theme 1. Importance of the potato crop Theme 2. Understanding the crop cycle of potato Module 2: Soil, crop and water management Theme 3. Land selection and crop rotation Theme 4. Land preparation Theme 5. Application of manure, compost and mineral fertilisers Theme 6. Planting techniques Theme 7. Weeding and hilling Theme 8. Irrigation Theme 9. Intercropping potatoes Module 3: Pest and disease management Theme 10. The disease triangle Theme 11. Control of late blight Theme 12. Control of bacterial wilt Theme 13. Control of soft rot (or blackleg) Theme 14. Control of viral diseases Theme 15. Control of potato tuber moth Theme 16. Control of nematodes Theme 17. Safe use of pesticides Module 4: Post maturity practices Theme 18. Harvesting Theme 19. Sorting and grading tubers for the market Theme 20. Storage of ware potatoes The sequence of modules and themes follows a certain logic as per the growth and development cycle of the potato crop. Therefore, it is recommended to follow the same sequence during training sessions. This guide can be used either for the training of trainers (the training of potential trainers of producers) or directly for the training of producers. For each theme, the trainer-of-trainers or the trainer should allocate a minimum of 15 minutes for presentation and 10 minutes for questions and answers. In total, the course requires a minimum of 8 hours to be completed, equivalent to a 2-day training workshop for the trainers or 4 training sessions of 2 hours for the producers. In a bid to gauge the impact made in training at any level, trainers are encouraged to assess participants’ knowledge through a written test before and after the training using the same questionnaire. A test sample is provided in appendices. It is recommended that the trainers pass the evaluation test with a score of at least 12/20. 3 Training materials Producer handout This course is designed to be a complete set of training materials for easy or scale out. The training materials This is a pocket-size handbook that the trained producers use. It is recommended to distribute the manual after are modular to facilitate use by various stakeholders focusing on different aspects of crop production. Four completion of the training. If the acquisition of the manual takes place before the training, it may provide types of tools are provided to facilitate the training of trainers and then cascade down the training to participants with an excuse to skip training sessions or for them to lose focus during training. In this regard, the producers. Those materials are the following: Producer handout could be considered as an incentive for completion of the training by producers. 1) Trainer Guide Demo Guide 2) Trainer Visual Aid This guide is a complementary support tool to the training materials. Therefore, it is not meant to be used 3) Producer handout alone. It helps the trainer to organize and facilitate hands-on training in the field, to complement the more 4) Demo Guide theoretical training sessions elaborated in the Trainer Guide. It comprises three demonstration protocols: (i) Trainer Guide crop husbandry, (ii) positive selection and (iii) small plot technique. For each demo, the guide provides The Trainer Guide is the master document printed in A4 format. It comprises three major parts: responses to the following questions: What, Why, When, For how long, With what and How. The How includes both text and images in a bid to clarify the different steps required in each training session. When planning a (i) the course overview, (ii) the 4 training modules with 20 themes also found in the Producer handout, and (iii) demo training session, the trainer should consider four successive steps: (i) Introduction to (or brief refresher the appendices. The course overview presents the training curriculum and all materials to be used. The second explanation on) the topic; (ii) the practice of the demo as per the demo guide; (iii) a session of questions and part of the guide consists of the training modules, alongside with instructions for trainers. In the last part answers among participants; and then (iv) the way forward for the next training session. (appendices), the Guide provides suggested questions and take-home messages per theme as outlined in the Trainer Visual Aid, as well as a test sample for pre- and post-training knowledge assessment. Visual Aid The Trainer Visual Aid is a didactic tool which helps the trainer to train participants. The front page contains an image which depicts the topic. That is the image participants see. The rear page is reserved for the trainer, and it includes four components for each of the 20 themes: (i) a small format of the front-page image; (ii) a brief summary of the theory in bullet points in which keywords are provided in bold, (iii) three guiding questions, and (iv) a take-home message. The small image helps the trainers remain focused on the topic. Brainstorming on the image can be done using the front page one. In his/her introduction to the topic, the trainer may ask participants to critically look at the image and describe what they understand from it. For each figure, three questions are suggested to recap and confirm whether the participants understood the topic or not. The trainer closes the topic with a take-home message. Training curriculum This course on Good agricultural practices for ware potato production in Rwanda comprises 4 modules and 20 themes, as outlined below: Module 1: Introduction to the potato crop Theme 1. Importance of the potato crop Theme 2. Understanding the crop cycle of potato Module 2: Soil, crop and water management Theme 3. Land selection and crop rotation Theme 4. Land preparation Theme 5. Application of manure, compost and mineral fertilisers Theme 6. Planting techniques Theme 7. Weeding and hilling Theme 8. Irrigation Theme 9. Intercropping potatoes Module 3: Pest and disease management Theme 10. The disease triangle Theme 11. Control of late blight Theme 12. Control of bacterial wilt Theme 13. Control of soft rot (or blackleg) Theme 14. Control of viral diseases Theme 15. Control of potato tuber moth Theme 16. Control of nematodes Theme 17. Safe use of pesticides Module 4: Post maturity practices Theme 18. Harvesting Theme 19. Sorting and grading tubers for the market Theme 20. Storage of ware potatoes The sequence of modules and themes follows a certain logic as per the growth and development cycle of the potato crop. Therefore, it is recommended to follow the same sequence during training sessions. This guide can be used either for the training of trainers (the training of potential trainers of producers) or directly for the training of producers. For each theme, the trainer-of-trainers or the trainer should allocate a minimum of 15 minutes for presentation and 10 minutes for questions and answers. In total, the course requires a minimum of 8 hours to be completed, equivalent to a 2-day training workshop for the trainers or 4 training sessions of 2 hours for the producers. In a bid to gauge the impact made in training at any level, trainers are encouraged to assess participants’ knowledge through a written test before and after the training using the same questionnaire. A test sample is provided in appendices. It is recommended that the trainers pass the evaluation test with a score of at least 12/20. Training materials Producer handout This course is designed to be a complete set of training materials for easy or scale out. The training materials This is a pocket-size handbook that the trained producers use. It is recommended to distribute the manual after are modular to facilitate use by various stakeholders focusing on different aspects of crop production. Four completion of the training. If the acquisition of the manual takes place before the training, it may provide types of tools are provided to facilitate the training of trainers and then cascade down the training to participants with an excuse to skip training sessions or for them to lose focus during training. In this regard, the producers. Those materials are the following: Producer handout could be considered as an incentive for completion of the training by producers. 1) Trainer Guide Demo Guide 2) Trainer Visual Aid This guide is a complementary support tool to the training materials. Therefore, it is not meant to be used 3) Producer handout alone. It helps the trainer to organize and facilitate hands-on training in the field, to complement the more 4) Demo Guide theoretical training sessions elaborated in the Trainer Guide. It comprises three demonstration protocols: (i) Trainer Guide crop husbandry, (ii) positive selection and (iii) small plot technique. For each demo, the guide provides The Trainer Guide is the master document printed in A4 format. It comprises three major parts: responses to the following questions: What, Why, When, For how long, With what and How. The How includes both text and images in a bid to clarify the different steps required in each training session. When planning a (i) the course overview, (ii) the 4 training modules with 20 themes also found in the Producer handout, and (iii) demo training session, the trainer should consider four successive steps: (i) Introduction to (or brief refresher the appendices. The course overview presents the training curriculum and all materials to be used. The second explanation on) the topic; (ii) the practice of the demo as per the demo guide; (iii) a session of questions and part of the guide consists of the training modules, alongside with instructions for trainers. In the last part answers among participants; and then (iv) the way forward for the next training session. (appendices), the Guide provides suggested questions and take-home messages per theme as outlined in the Trainer Visual Aid, as well as a test sample for pre- and post-training knowledge assessment. Visual Aid The Trainer Visual Aid is a didactic tool which helps the trainer to train participants. The front page contains an image which depicts the topic. That is the image participants see. The rear page is reserved for the trainer, and it includes four components for each of the 20 themes: (i) a small format of the front-page image; (ii) a brief summary of the theory in bullet points in which keywords are provided in bold, (iii) three guiding questions, and (iv) a take-home message. The small image helps the trainers remain focused on the topic. Brainstorming on the image can be done using the front page one. In his/her introduction to the topic, the trainer may ask participants to critically look at the image and describe what they understand from it. For each figure, three questions are suggested to recap and confirm whether the participants understood the topic or not. The trainer closes the topic with a take-home message. 4 Training curriculum This course on Good agricultural practices for ware potato production in Rwanda comprises 4 modules and 20 themes, as outlined below: Module 1: Introduction to the potato crop Theme 1. Importance of the potato crop Theme 2. Understanding the crop cycle of potato Module 2: Soil, crop and water management Theme 3. Land selection and crop rotation Theme 4. Land preparation Theme 5. Application of manure, compost and mineral fertilisers Theme 6. Planting techniques Theme 7. Weeding and hilling Theme 8. Irrigation Theme 9. Intercropping potatoes Module 3: Pest and disease management Theme 10. The disease triangle Theme 11. Control of late blight Theme 12. Control of bacterial wilt Theme 13. Control of soft rot (or blackleg) Theme 14. Control of viral diseases Theme 15. Control of potato tuber moth Theme 16. Control of nematodes Theme 17. Safe use of pesticides Module 4: Post maturity practices Theme 18. Harvesting Theme 19. Sorting and grading tubers for the market Theme 20. Storage of ware potatoes The sequence of modules and themes follows a certain logic as per the growth and development cycle of the potato crop. Therefore, it is recommended to follow the same sequence during training sessions. This guide can be used either for the training of trainers (the training of potential trainers of producers) or directly for the training of producers. For each theme, the trainer-of-trainers or the trainer should allocate a minimum of 15 minutes for presentation and 10 minutes for questions and answers. In total, the course requires a minimum of 8 hours to be completed, equivalent to a 2-day training workshop for the trainers or 4 training sessions of 2 hours for the producers. In a bid to gauge the impact made in training at any level, trainers are encouraged to assess participants’ knowledge through a written test before and after the training using the same questionnaire. A test sample is provided in appendices. It is recommended that the trainers pass the evaluation test with a score of at least 12/20. Training materials Producer handout This course is designed to be a complete set of training materials for easy or scale out. The training materials This is a pocket-size handbook that the trained producers use. It is recommended to distribute the manual after are modular to facilitate use by various stakeholders focusing on different aspects of crop production. Four completion of the training. If the acquisition of the manual takes place before the training, it may provide types of tools are provided to facilitate the training of trainers and then cascade down the training to participants with an excuse to skip training sessions or for them to lose focus during training. In this regard, the producers. Those materials are the following: Producer handout could be considered as an incentive for completion of the training by producers. 1) Trainer Guide Demo Guide 2) Trainer Visual Aid This guide is a complementary support tool to the training materials. Therefore, it is not meant to be used 3) Producer handout alone. It helps the trainer to organize and facilitate hands-on training in the field, to complement the more 4) Demo Guide theoretical training sessions elaborated in the Trainer Guide. It comprises three demonstration protocols: (i) Trainer Guide crop husbandry, (ii) positive selection and (iii) small plot technique. For each demo, the guide provides The Trainer Guide is the master document printed in A4 format. It comprises three major parts: responses to the following questions: What, Why, When, For how long, With what and How. The How includes both text and images in a bid to clarify the different steps required in each training session. When planning a (i) the course overview, (ii) the 4 training modules with 20 themes also found in the Producer handout, and (iii) demo training session, the trainer should consider four successive steps: (i) Introduction to (or brief refresher the appendices. The course overview presents the training curriculum and all materials to be used. The second explanation on) the topic; (ii) the practice of the demo as per the demo guide; (iii) a session of questions and part of the guide consists of the training modules, alongside with instructions for trainers. In the last part answers among participants; and then (iv) the way forward for the next training session. (appendices), the Guide provides suggested questions and take-home messages per theme as outlined in the Trainer Visual Aid, as well as a test sample for pre- and post-training knowledge assessment. Visual Aid The Trainer Visual Aid is a didactic tool which helps the trainer to train participants. The front page contains an image which depicts the topic. That is the image participants see. The rear page is reserved for the trainer, and it includes four components for each of the 20 themes: (i) a small format of the front-page image; (ii) a brief summary of the theory in bullet points in which keywords are provided in bold, (iii) three guiding questions, and (iv) a take-home message. The small image helps the trainers remain focused on the topic. Brainstorming on the image can be done using the front page one. In his/her introduction to the topic, the trainer may ask participants to critically look at the image and describe what they understand from it. For each figure, three questions are suggested to recap and confirm whether the participants understood the topic or not. The trainer closes the topic with a take-home message. 5 Training curriculum This course on Good agricultural practices for ware potato production in Rwanda comprises 4 modules and 20 themes, as outlined below: Module 1: Introduction to the potato crop Theme 1. Importance of the potato crop Theme 2. Understanding the crop cycle of potato Module 2: Soil, crop and water management Theme 3. Land selection and crop rotation Theme 4. Land preparation Theme 5. Application of manure, compost and mineral fertilisers Theme 6. Planting techniques Theme 7. Weeding and hilling Theme 8. Irrigation Theme 9. Intercropping potatoes Module 3: Pest and disease management Theme 10. The disease triangle Theme 11. Control of late blight Theme 12. Control of bacterial wilt Theme 13. Control of soft rot (or blackleg) Theme 14. Control of viral diseases Theme 15. Control of potato tuber moth Theme 16. Control of nematodes Theme 17. Safe use of pesticides Module 4: Post maturity practices Theme 18. Harvesting Theme 19. Sorting and grading tubers for the market Theme 20. Storage of ware potatoes The sequence of modules and themes follows a certain logic as per the growth and development cycle of the potato crop. Therefore, it is recommended to follow the same sequence during training sessions. This guide can be used either for the training of trainers (the training of potential trainers of producers) or directly for the training of producers. For each theme, the trainer-of-trainers or the trainer should allocate a minimum of 15 minutes for presentation and 10 minutes for questions and answers. In total, the course requires a minimum of 8 hours to be completed, equivalent to a 2-day training workshop for the trainers or 4 training sessions of 2 hours for the producers. In a bid to gauge the impact made in training at any level, trainers are encouraged to assess participants’ knowledge through a written test before and after the training using the same questionnaire. A test sample is provided in appendices. It is recommended that the trainers pass the evaluation test with a score of at least 12/20. Training materials Producer handout Module 1 Introduction to the potato crop This course is designed to be a complete set of training materials for easy or scale out. The training materials This is a pocket-size handbook that the trained producers use. It is recommended to distribute the manual after are modular to facilitate use by various stakeholders focusing on different aspects of crop production. Four completion of the training. If the acquisition of the manual takes place before the training, it may provide Theme 1. Importance of the potato crop types of tools are provided to facilitate the training of trainers and then cascade down the training to participants with an excuse to skip training sessions or for them to lose focus during training. In this regard, the producers. Those materials are the following: Producer handout could be considered as an incentive for completion of the training by producers. 1) Trainer Guide Demo Guide 2) Trainer Visual Aid This guide is a complementary support tool to the training materials. Therefore, it is not meant to be used 3) Producer handout alone. It helps the trainer to organize and facilitate hands-on training in the field, to complement the more 4) Demo Guide theoretical training sessions elaborated in the Trainer Guide. It comprises three demonstration protocols: (i) Trainer Guide crop husbandry, (ii) positive selection and (iii) small plot technique. For each demo, the guide provides The Trainer Guide is the master document printed in A4 format. It comprises three major parts: responses to the following questions: What, Why, When, For how long, With what and How. The How includes both text and images in a bid to clarify the different steps required in each training session. When planning a (i) the course overview, (ii) the 4 training modules with 20 themes also found in the Producer handout, and (iii) demo training session, the trainer should consider four successive steps: (i) Introduction to (or brief refresher the appendices. The course overview presents the training curriculum and all materials to be used. The second explanation on) the topic; (ii) the practice of the demo as per the demo guide; (iii) a session of questions and part of the guide consists of the training modules, alongside with instructions for trainers. In the last part answers among participants; and then (iv) the way forward for the next training session. (appendices), the Guide provides suggested questions and take-home messages per theme as outlined in the Trainer Visual Aid, as well as a test sample for pre- and post-training knowledge assessment. Visual Aid The Trainer Visual Aid is a didactic tool which helps the trainer to train participants. The front page contains an image which depicts the topic. That is the image participants see. The rear page is reserved for the trainer, and it includes four components for each of the 20 themes: (i) a small format of the front-page image; (ii) a brief summary of the theory in bullet points in which keywords are provided in bold, (iii) three guiding questions, and (iv) a take-home message. The small image helps the trainers remain focused on the topic. Brainstorming on the image can be done using the front page one. In his/her introduction to the topic, the trainer may ask participants to critically look at the image and describe what they understand from it. For each figure, three questions are suggested to recap and confirm whether the participants understood the topic or not. The Even with low yields many farmers still prefer trainer closes the topic with a take-home message. growing potato because of its profitability Ask participants to list the major food compared to alternative crops that are grown in crops grown in their area. Then, ask them the same area. to rank those crops in relation to income generation. This helps to find out the Before venturing into potato agri-business, the comparative importance of potato following conditions must be fulfilled: 1) Have minimum access to knowledge or technical backstopping on good agricultural practices for ware potato production. The potato crop comes from the highlands of South 2) Land free of potato diseases is available. America from where it was spread all over the world, 3) Resources to purchase inputs (e.g. seed, including Africa. The crop is currently the third food crop fertilizers and pesticides) are available. in the world, after wheat and rice. It produces more 4) Good quality seed of desired varieties is calories per unit of area and time than any other crop available and accessible. grown in cool climates. 5) Production plan for the next three or more Besides having a high nutritional value, potato is one of seasons (indicating area to be grown each the most important cash crops in many countries, season and the sources of seed) is prepared. including Rwanda. 6) Target market for the produce is identified Average potato yields in Rwanda are still low at less than before planting. 10 t/ha compared to up to 25 t/ha attained by some 7) Have a storage facility or post-harvest progressive farmers with good agricultural practices. handling plan of the produce. 6 Training curriculum This course on Good agricultural practices for ware potato production in Rwanda comprises 4 modules and 20 themes, as outlined below: Module 1: Introduction to the potato crop Theme 1. Importance of the potato crop Theme 2. Understanding the crop cycle of potato Module 2: Soil, crop and water management Theme 3. Land selection and crop rotation Theme 4. Land preparation Theme 5. Application of manure, compost and mineral fertilisers Theme 6. Planting techniques Theme 7. Weeding and hilling Theme 8. Irrigation Theme 9. Intercropping potatoes Module 3: Pest and disease management Theme 10. The disease triangle Theme 11. Control of late blight Theme 12. Control of bacterial wilt Theme 13. Control of soft rot (or blackleg) Theme 14. Control of viral diseases Theme 15. Control of potato tuber moth Theme 16. Control of nematodes Theme 17. Safe use of pesticides Module 4: Post maturity practices Theme 18. Harvesting Theme 19. Sorting and grading tubers for the market Theme 20. Storage of ware potatoes The sequence of modules and themes follows a certain logic as per the growth and development cycle of the potato crop. Therefore, it is recommended to follow the same sequence during training sessions. This guide can be used either for the training of trainers (the training of potential trainers of producers) or directly for the training of producers. For each theme, the trainer-of-trainers or the trainer should allocate a minimum of 15 minutes for presentation and 10 minutes for questions and answers. In total, the course requires a minimum of 8 hours to be completed, equivalent to a 2-day training workshop for the trainers or 4 training sessions of 2 hours for the producers. In a bid to gauge the impact made in training at any level, trainers are encouraged to assess participants’ knowledge through a written test before and after the training using the same questionnaire. A test sample is provided in appendices. It is recommended that the trainers pass the evaluation test with a score of at least 12/20. Training materials Producer handout Theme 2. Understanding the crop cycle of potato This course is designed to be a complete set of training materials for easy or scale out. The training materials This is a pocket-size handbook that the trained producers use. It is recommended to distribute the manual after are modular to facilitate use by various stakeholders focusing on different aspects of crop production. Four completion of the training. If the acquisition of the manual takes place before the training, it may provide types of tools are provided to facilitate the training of trainers and then cascade down the training to participants with an excuse to skip training sessions or for them to lose focus during training. In this regard, the producers. Those materials are the following: Producer handout could be considered as an incentive for completion of the training by producers. 1) Trainer Guide 3 4 Demo Guide 2) Trainer Visual Aid This guide is a complementary support tool to the training materials. Therefore, it is not meant to be used 3) Producer handout alone. It helps the trainer to organize and facilitate hands-on training in the field, to complement the more 4) Demo Guide 5 theoretical training sessions elaborated in the Trainer Guide. It comprises three demonstration protocols: (i) 2 Trainer Guide crop husbandry, (ii) positive selection and (iii) small plot technique. For each demo, the guide provides The Trainer Guide is the master document printed in A4 format. It comprises three major parts: responses to the following questions: What, Why, When, For how long, With what and How. The How includes both text and images in a bid to clarify the different steps required in each training session. When planning a (i) the course overview, (ii) the 4 training modules with 20 themes also found in the Producer handout, and (iii) demo training session, the trainer should consider four successive steps: (i) Introduction to (or brief refresher the appendices. The course overview presents the training curriculum and all materials to be used. The second 1 explanation on) the topic; (ii) the practice of the demo as per the demo guide; (iii) a session of questions and part of the guide consists of the training modules, alongside with instructions for trainers. In the last part answers among participants; and then (iv) the way forward for the next training session. (appendices), the Guide provides suggested questions and take-home messages per theme as outlined in the Trainer Visual Aid, as well as a test sample for pre- and post-training knowledge assessment. Visual Aid The Trainer Visual Aid is a didactic tool which helps the trainer to train participants. The front page contains an image which depicts the topic. That is the image participants see. The rear page is reserved for the trainer, and Sprout Vegetative Tuber it includes four components for each of the 20 themes: (i) a small format of the front-page image; (ii) a brief development growth initiation Tuber bulking Maturation summary of the theory in bullet points in which keywords are provided in bold, (iii) three guiding questions, and (iv) a take-home message. The small image helps the trainers remain focused on the topic. Brainstorming on the image can be done using the front page one. In his/her introduction to the topic, the trainer may ask participants to critically look at the image and describe what they understand from it. For each figure, three Understanding the different development stages of the potato crop will questions are suggested to recap and confirm whether the participants understood the topic or not. The help growers to know the right time to perform agronomic practices in the field to increase yields. Invite one or two trainer closes the topic with a take-home message. participants to The growth cycle of the crop can be divided into five stages which describe the five stages require timely and specific crop management operations. using their own words It is important to understand that the length of each growth stage of the potato crop is not fixed, but depends on variety, planting conditions, soil fertility, weather, etc. Unlike cereals, potato development stages overlap making it difficult to distinguish between stages. For example, in some cases during the early growth stages, tubers have already begun to grow from the roots. 7 Growth stage 1 • Sprout development and emergence This stage begins when sprouted tubers are planted and ends when plants emerge from the soil (emergence). In normal conditions, this stage lasts 2 to 4 weeks, but it can also be longer depending on planting conditions such as soil type and moisture, seed physiological age, planting depth, soil temperature, etc. It is highly recommended to plant well sprouted tubers with multiple (minimum 3) and strong sprouts to ensure uniform emergence of multi-stem plants in the field. This stage is very critical in the crop growth cycle, because the harvest is strongly related to the seed quality used and number of stems per seed. Growth stage 2 • Vegetative growth This stage starts from plant emergence and ends at tuber initiation. It lasts 2 to 4 weeks after emergence, but this period strongly depends on the variety used. Some varieties start forming tubers much earlier than others. During this stage it is critical to protect the crop against diseases such as late blight. Growth stage 3 • Tuber initiation This is a relatively short stage in which tubers begin to form at the end of stolons (tuber forming roots) but are not yet enlarging. In most varieties this stage coincides with early flowering, marking the end of leaf growth. This means that all leaves are formed and fully grown. The crop reaches its maximum coverage of the soil. At this stage it is important to have enough soil around the stems through proper hilling. Growth stage 4 • Tuber bulking At this stage, leave development has stopped and tubers become bigger. The leaves eventually turn yellow and die. It is important to wait with the harvest until total death of the foliage has occurred because yield increases significantly at this stage. Foliage should remain protected against pests and diseases until dehaulming or Like any other crop, potato requires adequate natural death. However, chemical applications (fungicides and insecticides) must stop at 3 weeks before harvest. nutrients from organic inputs (manure or compost) and/or mineral fertilizers to grow well. Growth stage 5 • Maturation Nitrogen (N), phosphorus (P) and potassium (K) This is the maturity stage of the crop. The plants have died and there is no more crop growth. The tuber skins are the most important nutrients for a potato gradually harden due to increasing starch content. crop. A potato crop yielding 10 t/ha removes around 40 kg of N, 10 kg of P and 50 kg of K from the soil, and these nutrients need to be replaced to avoid soil fertility decline. N and P are important during the whole crop growth cycle, while K is most needed during tuber bulking. Depending on soil type, it may be beneficial to The best fertilizer responses can be expected when also apply secondary or micronutrients such as quantities and types of fertilizer to be applied are Ca, Mg, S and Zn. determined based on soil type and field history. This is Excessive application of fertilizers can damage called site-specific fertilizer management. Tools to provide plants and the environment and is a wastage of site-specific fertilizer recommendations based on soil money, while applying too little can result in analysis or digital soil maps are increasingly available, and plants not growing to their optimum size. farmers should seek for the best available and most Fertilization with high amounts of N containing updated recommendations at the start of each season. fertilizer should be avoided because it In case a site-specific recommendation is not available, it encourages excessive foliage growth, depressed is recommended to apply 3 kg of NPK 17-17-17 per are tuber growth and it may produce tubers with (100 sqm) divided into 2 applications (1.5 kg per are at hollow hearts. planting and 1.5 kg per are at top-dressing). In practical 8 terms, apply the content of 1 plastic water or soda Manure, compost and mineral fertilizer must be bottle cap per two seed tubers or plants at each mixed well with soil to avoid direct contact with application. Apply 1 cap of NPK 17-17-17 per two seed planted tubers. Apply the manure or compost first, tubers at planting and 1 cap of NPK 17-17-17 per two then add the fertilizers, and cover with 5-10 cm of soil. plants as top-dressing 1-2 weeks after plant emer- Then place the seed potato. To fertilize the crop after gence at the first weeding and hilling up. Farmers who emergence, dig one small hole at around 10-15 cm are not able to apply fertilizers after emergence, can from the plant base using a stick. Put fertilizers and apply all at planting. Also, if a farmer fails to apply cover with soil using hands or the stick. fertilizers at planting, he/she may apply all after In acidic soils (soils with a pH below 5.5), in addition emergence. to manure or compost and mineral fertilizers, lime Mineral fertilizer is best combined with manure or should be applied to avoid poor nutrient availabilities compost. Up to two handfuls of well decomposed and soil toxicities. Lime should be applied during land manure or compost can be applied per seed tuber. This preparation at a rate of 25 to 50 kg per are (100 sqm). is equivalent to around 200- 300 kg of manure or In fields where lime has been applied previously, the compost per are (100 sqm). This is very useful on poor pH of the soil should be measured at the start of soils. It is not recommended for rich soils such as forest subsequent seasons and lime should be re-applied soils. Manure and/or compost should be applied only when the pH drops below 5.5. Either travertine or during land preparation or at planting. Kitchen dolomitic lime can be used, but travertine may be compost containing potato, tomato, eggplant, pepper more profitable as it is less expensive. The use of or other solanaceous crops should never be used as it acidifying mineral fertilizers such as urea, may carry potato diseases. di-ammonium phosphate and ammonium sulphate should be avoided in acidic soil. over a period of 3 seasons. While growing other crops in Sometimes farmers choose not to respect rotation Module 2 Soil, crop and water management rotation with potato, care should be taken that all requirements for potato, because they need the potato plants sprouted from left-over tubers are income from growing potatoes. It is important to Theme 3: Land selection and crop rotation removed in the following crops. These volunteer potato note that this will lead to declining yield levels of plants will maintain pathogen populations in the field potato, and to reduced profits in the long term. resulting in lower potato yields in subsequent seasons. Proper rotation will result in higher and more sustainable potato yields. Cereals (maize/wheat) Potatoes Legumes (beans/soya/ Like any other crop, potato requires adequate peas) nutrients from organic inputs (manure or compost) and/or mineral fertilizers to grow well. Nitrogen (N), phosphorus (P) and potassium (K) Potatoes like a cool environment (average are the most important nutrients for a potato temperature of 15-20°C). Therefore, plant potatoes crop. A potato crop yielding 10 t/ha removes in an area that is not too hot, and select an open Ask participants to discuss which other around 40 kg of N, 10 kg of P and 50 kg of K from site, without shade. In Rwanda, potatoes are mainly crops can be grown in rotation with the soil, and these nutrients need to be replaced grown in the highland regions (above 1,800 m.a.s.l.) potato in their area. Emphasize the crucial to avoid soil fertility decline. N and P are of Birunga, Buberuka and the Congo Nile role of rotation to avoid yield reductions important during the whole crop growth cycle, watershed divine (Northern, Southern and Western due to pests and diseases while K is most needed during tuber bulking. Province). The soil should be deep, well drained and Depending on soil type, it may be beneficial to The best fertilizer responses can be expected when loose for proper development of roots, stolons and also apply secondary or micronutrients such as quantities and types of fertilizer to be applied are tubers. The site should be free of soil borne pests Ca, Mg, S and Zn. determined based on soil type and field history. This is and diseases, such as nematodes and bacterial wilt. potatoes should not follow potatoes or other crops of To reduce the risk of pests and diseases, select a site the same family which are susceptible to the same Excessive application of fertilizers can damage called site-specific fertilizer management. Tools to provide site-specific fertilizer recommendations based on soil where potato has not been grown for at least the diseases and maintain pathogen populations in the field. plants and the environment and is a wastage of last 2, and preferably 4 consecutive seasons. Examples of crops from the same family as potato are money, while applying too little can result in analysis or digital soil maps are increasingly available, and plants not growing to their optimum size. farmers should seek for the best available and most Crop rotation is very important to maintain soil eggplant, pepper, tomato and tobacco. Avoid planting Fertilization with high amounts of N containing updated recommendations at the start of each season. quality and ensure potato pests and diseases do maize before potato in fields with a history of infestation fertilizer should be avoided because it In case a site-specific recommendation is not available, it not continue to build up in the field. Plan for a by nematodes or low soil fertility. encourages excessive foliage growth, depressed is recommended to apply 3 kg of NPK 17-17-17 per are rotation scheme of at least 3 seasons (1 with potato The recommended rotation system with potato in tuber growth and it may produce tubers with (100 sqm) divided into 2 applications (1.5 kg per are at and 2 with other crops) in which potatoes are Rwanda is to subsequently cultivate legumes and cereals hollow hearts. planting and 1.5 kg per are at top-dressing). In practical rotated with other crops, keeping in mind that (e.g. potato - beans/soja/peas - maize/wheat - potato) 9 terms, apply the content of 1 plastic water or soda Manure, compost and mineral fertilizer must be bottle cap per two seed tubers or plants at each mixed well with soil to avoid direct contact with application. Apply 1 cap of NPK 17-17-17 per two seed planted tubers. Apply the manure or compost first, tubers at planting and 1 cap of NPK 17-17-17 per two then add the fertilizers, and cover with 5-10 cm of soil. plants as top-dressing 1-2 weeks after plant emer- Then place the seed potato. To fertilize the crop after gence at the first weeding and hilling up. Farmers who emergence, dig one small hole at around 10-15 cm are not able to apply fertilizers after emergence, can from the plant base using a stick. Put fertilizers and apply all at planting. Also, if a farmer fails to apply cover with soil using hands or the stick. fertilizers at planting, he/she may apply all after In acidic soils (soils with a pH below 5.5), in addition emergence. to manure or compost and mineral fertilizers, lime Mineral fertilizer is best combined with manure or should be applied to avoid poor nutrient availabilities compost. Up to two handfuls of well decomposed and soil toxicities. Lime should be applied during land manure or compost can be applied per seed tuber. This preparation at a rate of 25 to 50 kg per are (100 sqm). is equivalent to around 200- 300 kg of manure or In fields where lime has been applied previously, the compost per are (100 sqm). This is very useful on poor pH of the soil should be measured at the start of soils. It is not recommended for rich soils such as forest subsequent seasons and lime should be re-applied soils. Manure and/or compost should be applied only when the pH drops below 5.5. Either travertine or during land preparation or at planting. Kitchen dolomitic lime can be used, but travertine may be compost containing potato, tomato, eggplant, pepper more profitable as it is less expensive. The use of or other solanaceous crops should never be used as it acidifying mineral fertilizers such as urea, may carry potato diseases. di-ammonium phosphate and ammonium sulphate should be avoided in acidic soil. over a period of 3 seasons. While growing other crops in Sometimes farmers choose not to respect rotation rotation with potato, care should be taken that all requirements for potato, because they need the potato plants sprouted from left-over tubers are income from growing potatoes. It is important to removed in the following crops. These volunteer potato note that this will lead to declining yield levels of plants will maintain pathogen populations in the field potato, and to reduced profits in the long term. resulting in lower potato yields in subsequent seasons. Proper rotation will result in higher and more sustainable potato yields. Theme 4: Land preparation Like any other crop, potato requires adequate nutrients from organic inputs (manure or compost) and/or mineral fertilizers to grow well. Nitrogen (N), phosphorus (P) and potassium (K) Potatoes like a cool environment (average are the most important nutrients for a potato temperature of 15-20°C). Therefore, plant potatoes crop. A potato crop yielding 10 t/ha removes in an area that is not too hot, and select an open It is essential to prepare soil early in the season, at least two weeks around 40 kg of N, 10 kg of P and 50 kg of K from site, without shade. In Rwanda, potatoes are mainly before planting, when the soil is still partially dry to prevent soil the soil, and these nutrients need to be replaced grown in the highland regions (above 1,800 m.a.s.l.) compaction. The land should be prepared in dry weather and not Discuss with to avoid soil fertility decline. N and P are of Birunga, Buberuka and the Congo Nile when it is raining. Potato requires loose soil to maximize growth, participants the important during the whole crop growth cycle, watershed divine (Northern, Southern and Western bulking potential and consequently yields. It is therefore possibilities for while K is most needed during tuber bulking. Province). The soil should be deep, well drained and recommended to plough the soil to a depth of 30 cm. Prepare land mechanized land Depending on soil type, it may be beneficial to The best fertilizer responses can be expected when loose for proper development of roots, stolons and until the ground becomes soft, free from clods. Keep in mind that preparation in their area also apply secondary or micronutrients such as quantities and types of fertilizer to be applied are tubers. The site should be free of soil borne pests land prepared to a depth of less than 30 cm will lead to lower and its advantages and Ca, Mg, S and Zn. determined based on soil type and field history. This is and diseases, such as nematodes and bacterial wilt. potatoes should not follow potatoes or other crops of yields. Land preparation consists of: disadvantages To reduce the risk of pests and diseases, select a site the same family which are susceptible to the same Excessive application of fertilizers can damage called site-specific fertilizer management. Tools to provide 1) Clearing, raking and stumping (removal of weeds and stones). site-specific fertilizer recommendations based on soil where potato has not been grown for at least the diseases and maintain pathogen populations in the field. plants and the environment and is a wastage of 2) Ploughing (using a hoe, animal-drawn plough, motocultivator last 2, and preferably 4 consecutive seasons. Examples of crops from the same family as potato are money, while applying too little can result in analysis or digital soil maps are increasingly available, and or tractor-drawn plough). farmers should seek for the best available and most Crop rotation is very important to maintain soil eggplant, pepper, tomato and tobacco. Avoid planting plants not growing to their optimum size. 3) Harrowing. quality and ensure potato pests and diseases do maize before potato in fields with a history of infestation Fertilization with high amounts of N containing updated recommendations at the start of each season. 4) Ridging (in case of risk of erosion or poor drainage). not continue to build up in the field. Plan for a by nematodes or low soil fertility. fertilizer should be avoided because it In case a site-specific recommendation is not available, it encourages excessive foliage growth, depressed is recommended to apply 3 kg of NPK 17-17-17 per are rotation scheme of at least 3 seasons (1 with potato The recommended rotation system with potato in tuber growth and it may produce tubers with (100 sqm) divided into 2 applications (1.5 kg per are at and 2 with other crops) in which potatoes are Rwanda is to subsequently cultivate legumes and cereals hollow hearts. planting and 1.5 kg per are at top-dressing). In practical rotated with other crops, keeping in mind that (e.g. potato - beans/soja/peas - maize/wheat - potato) 10 terms, apply the content of 1 plastic water or soda Manure, compost and mineral fertilizer must be bottle cap per two seed tubers or plants at each mixed well with soil to avoid direct contact with application. Apply 1 cap of NPK 17-17-17 per two seed planted tubers. Apply the manure or compost first, tubers at planting and 1 cap of NPK 17-17-17 per two then add the fertilizers, and cover with 5-10 cm of soil. plants as top-dressing 1-2 weeks after plant emer- Then place the seed potato. To fertilize the crop after gence at the first weeding and hilling up. Farmers who emergence, dig one small hole at around 10-15 cm are not able to apply fertilizers after emergence, can from the plant base using a stick. Put fertilizers and apply all at planting. Also, if a farmer fails to apply cover with soil using hands or the stick. fertilizers at planting, he/she may apply all after In acidic soils (soils with a pH below 5.5), in addition emergence. to manure or compost and mineral fertilizers, lime Mineral fertilizer is best combined with manure or should be applied to avoid poor nutrient availabilities compost. Up to two handfuls of well decomposed and soil toxicities. Lime should be applied during land manure or compost can be applied per seed tuber. This preparation at a rate of 25 to 50 kg per are (100 sqm). is equivalent to around 200- 300 kg of manure or In fields where lime has been applied previously, the compost per are (100 sqm). This is very useful on poor pH of the soil should be measured at the start of soils. It is not recommended for rich soils such as forest subsequent seasons and lime should be re-applied soils. Manure and/or compost should be applied only when the pH drops below 5.5. Either travertine or during land preparation or at planting. Kitchen dolomitic lime can be used, but travertine may be compost containing potato, tomato, eggplant, pepper more profitable as it is less expensive. The use of or other solanaceous crops should never be used as it acidifying mineral fertilizers such as urea, may carry potato diseases. di-ammonium phosphate and ammonium sulphate should be avoided in acidic soil. 30 - 40 cm Theme 5: Application of manure, compost and mineral fertilizers Like any other crop, potato requires adequate nutrients from organic inputs (manure or Inform participants that the best way to compost) and/or mineral fertilizers to grow well. determine the quantities and types of Nitrogen (N), phosphorus (P) and potassium (K) fertilizer to be applied is to get a are the most important nutrients for a potato recommendation based on soil type and crop. A potato crop yielding 10 t/ha removes field history. Discuss whether site-specific around 40 kg of N, 10 kg of P and 50 kg of K from recommendations are available and how the soil, and these nutrients need to be replaced they can be accessed to avoid soil fertility decline. N and P are important during the whole crop growth cycle, while K is most needed during tuber bulking. Depending on soil type, it may be beneficial to The best fertilizer responses can be expected when also apply secondary or micronutrients such as quantities and types of fertilizer to be applied are Ca, Mg, S and Zn. determined based on soil type and field history. This is Excessive application of fertilizers can damage called site-specific fertilizer management. Tools to provide plants and the environment and is a wastage of site-specific fertilizer recommendations based on soil money, while applying too little can result in analysis or digital soil maps are increasingly available, and plants not growing to their optimum size. farmers should seek for the best available and most Fertilization with high amounts of N containing updated recommendations at the start of each season. fertilizer should be avoided because it In case a site-specific recommendation is not available, it encourages excessive foliage growth, depressed is recommended to apply 3 kg of NPK 17-17-17 per are tuber growth and it may produce tubers with (100 sqm) divided into 2 applications (1.5 kg per are at hollow hearts. planting and 1.5 kg per are at top-dressing). In practical 11 terms, apply the content of 1 plastic water or soda Manure, compost and mineral fertilizer must be bottle cap per two seed tubers or plants at each mixed well with soil to avoid direct contact with application. Apply 1 cap of NPK 17-17-17 per two seed planted tubers. Apply the manure or compost first, tubers at planting and 1 cap of NPK 17-17-17 per two then add the fertilizers, and cover with 5-10 cm of soil. plants as top-dressing 1-2 weeks after plant emer- Then place the seed potato. To fertilize the crop after gence at the first weeding and hilling up. Farmers who emergence, dig one small hole at around 10-15 cm are not able to apply fertilizers after emergence, can from the plant base using a stick. Put fertilizers and apply all at planting. Also, if a farmer fails to apply cover with soil using hands or the stick. fertilizers at planting, he/she may apply all after In acidic soils (soils with a pH below 5.5), in addition emergence. to manure or compost and mineral fertilizers, lime Mineral fertilizer is best combined with manure or should be applied to avoid poor nutrient availabilities compost. Up to two handfuls of well decomposed and soil toxicities. Lime should be applied during land manure or compost can be applied per seed tuber. This preparation at a rate of 25 to 50 kg per are (100 sqm). is equivalent to around 200- 300 kg of manure or In fields where lime has been applied previously, the compost per are (100 sqm). This is very useful on poor pH of the soil should be measured at the start of soils. It is not recommended for rich soils such as forest subsequent seasons and lime should be re-applied soils. Manure and/or compost should be applied only when the pH drops below 5.5. Either travertine or during land preparation or at planting. Kitchen dolomitic lime can be used, but travertine may be compost containing potato, tomato, eggplant, pepper more profitable as it is less expensive. The use of or other solanaceous crops should never be used as it acidifying mineral fertilizers such as urea, may carry potato diseases. di-ammonium phosphate and ammonium sulphate should be avoided in acidic soil. Like any other crop, potato requires adequate nutrients from organic inputs (manure or compost) and/or mineral fertilizers to grow well. Nitrogen (N), phosphorus (P) and potassium (K) are the most important nutrients for a potato crop. A potato crop yielding 10 t/ha removes around 40 kg of N, 10 kg of P and 50 kg of K from the soil, and these nutrients need to be replaced to avoid soil fertility decline. N and P are important during the whole crop growth cycle, while K is most needed during tuber bulking. Depending on soil type, it may be beneficial to The best fertilizer responses can be expected when also apply secondary or micronutrients such as quantities and types of fertilizer to be applied are Ca, Mg, S and Zn. determined based on soil type and field history. This is Excessive application of fertilizers can damage called site-specific fertilizer management. Tools to provide plants and the environment and is a wastage of site-specific fertilizer recommendations based on soil money, while applying too little can result in analysis or digital soil maps are increasingly available, and plants not growing to their optimum size. farmers should seek for the best available and most Fertilization with high amounts of N containing updated recommendations at the start of each season. fertilizer should be avoided because it In case a site-specific recommendation is not available, it encourages excessive foliage growth, depressed is recommended to apply 3 kg of NPK 17-17-17 per are tuber growth and it may produce tubers with (100 sqm) divided into 2 applications (1.5 kg per are at hollow hearts. planting and 1.5 kg per are at top-dressing). In practical terms, apply the content of 1 plastic water or soda Manure, compost and mineral fertilizer must be Use certified seed or quality seed purchased from Two ways of planting potatoes are possible: planting bottle cap per two seed tubers or plants at each mixed well with soil to avoid direct contact with known seed producers or sources. The small plot into furrows or in holes. The two methods can application. Apply 1 cap of NPK 17-17-17 per two seed planted tubers. Apply the manure or compost first, technique can be used for on-farm bulking of produce the same results. Therefore, it is up to the tubers at planting and 1 cap of NPK 17-17-17 per two then add the fertilizers, and cover with 5-10 cm of soil. high-quality seeds sourced from trusted seed farmer to choose the easiest method. Planting on plants as top-dressing 1-2 weeks after plant emer- Then place the seed potato. To fertilize the crop after producers (see Demo Guide). This will reduce ridges or beds can be considered in fields with high gence at the first weeding and hilling up. Farmers who emergence, dig one small hole at around 10-15 cm significantly the amount of high-quality seeds that risk of erosion (steep slope and high rainfall) and/or are not able to apply fertilizers after emergence, can from the plant base using a stick. Put fertilizers and need to be purchased by the farmer. If using poor drainage. Prepare furrows or holes at a spacing apply all at planting. Also, if a farmer fails to apply cover with soil using hands or the stick. farm-saved seeds, tubers harvested from healthy between rows of 70-80 cm. If your variety produces fertilizers at planting, he/she may apply all after In acidic soils (soils with a pH below 5.5), in addition looking mother plants should be used. This abundant foliage and/or the slope is steep, the emergence. to manure or compost and mineral fertilizers, lime technique is called positive selection and requires spacing between lines can be increased to 90 cm. Mineral fertilizer is best combined with manure or should be applied to avoid poor nutrient availabilities hands-on training in the field (see Demo guide). Do Within rows, use a plant spacing of 25-35 cm compost. Up to two handfuls of well decomposed and soil toxicities. Lime should be applied during land not use small potatoes from the market for seed, depending on seed size, 25 cm when tubers are manure or compost can be applied per seed tuber. This preparation at a rate of 25 to 50 kg per are (100 sqm). they are unmarketable because they are small and small (around 30 mm of diameter), 30 cm when is equivalent to around 200- 300 kg of manure or In fields where lime has been applied previously, the full of diseases. tubers are medium sized (around 40 mm) and 35 cm compost per are (100 sqm). This is very useful on poor pH of the soil should be measured at the start of Ensure the seed tubers are well sprouted with for large tubers (like 50 mm of diameter). Farmers soils. It is not recommended for rich soils such as forest subsequent seasons and lime should be re-applied uniform sprout size of around 1-2 cm. At 4 to 6 weeks should avoid cutting large seed tubers into pieces, as soils. Manure and/or compost should be applied only when the pH drops below 5.5. Either travertine or before planting, the main sprout should be taken off this may spread diseases among tubers by during land preparation or at planting. Kitchen dolomitic lime can be used, but travertine may be to promote the development of more lateral sprouts. contaminated cutting equipment. compost containing potato, tomato, eggplant, pepper more profitable as it is less expensive. The use of Avoid old and dried out tubers with long, white Note that on a sloping terrain, furrows or holes or other solanaceous crops should never be used as it acidifying mineral fertilizers such as urea, sprouts which can break off during handling. Short should run across the slope to reduce soil erosion may carry potato diseases. di-ammonium phosphate and ammonium sulphate and strong, green sprouts will ensure that once and maintain runoff water within plant rows. After should be avoided in acidic soil. planted growth will be faster, uniform and the crop planting, tubers should be covered by enough soil will be more vigorous. It is important to handle the (10-15 cm). Uncovered holes or furrows should Theme 6: Planting techniques sprouted seed tubers with care during transport, always be avoided. packing and unpacking and planting, to avoid The quantity of seeds to be used per unit of area damage to sprouts. Seed potatoes damaged by pests depends on several factors, such as planting distance Ø : 30 mm Ø : 40 mm Ø : 50 mm or diseases should never be used for planting. Ensure and tuber size. The quantity of 2 t/ha is normally used as that seed tubers of the same size (category) are a reference, which is the quantity needed with a plant planted together in one area. This results in uniform spacing of 80x30 cm and averaged sized seed tubers of crop vegetation which will facilitate better around 50 g per tuber. This topic requires hands-on management. training in the field (see Demo Guide). A good crop starts with good seed. Plant good Emphasize that using disease-free, high quality seed of market-preferred varieties. Currently, quality seeds is the most important the most grown varieties in Rwanda are Sangema, yield-determining factor for potato. Cruza, Mabondo, Victoria, Kirundo, Mizero, Kigega, Discuss with farmers the different Ngunda, Nderera, Gikungu, Kinigi and Twihaze. possibilities to access clean seeds Seeds of the same variety should never be mixed. 12 Like any other crop, potato requires adequate nutrients from organic inputs (manure or compost) and/or mineral fertilizers to grow well. Nitrogen (N), phosphorus (P) and potassium (K) are the most important nutrients for a potato crop. A potato crop yielding 10 t/ha removes around 40 kg of N, 10 kg of P and 50 kg of K from the soil, and these nutrients need to be replaced to avoid soil fertility decline. N and P are important during the whole crop growth cycle, while K is most needed during tuber bulking. Depending on soil type, it may be beneficial to The best fertilizer responses can be expected when also apply secondary or micronutrients such as quantities and types of fertilizer to be applied are Ca, Mg, S and Zn. determined based on soil type and field history. This is Excessive application of fertilizers can damage called site-specific fertilizer management. Tools to provide plants and the environment and is a wastage of site-specific fertilizer recommendations based on soil money, while applying too little can result in analysis or digital soil maps are increasingly available, and plants not growing to their optimum size. farmers should seek for the best available and most Fertilization with high amounts of N containing updated recommendations at the start of each season. fertilizer should be avoided because it In case a site-specific recommendation is not available, it encourages excessive foliage growth, depressed is recommended to apply 3 kg of NPK 17-17-17 per are tuber growth and it may produce tubers with (100 sqm) divided into 2 applications (1.5 kg per are at hollow hearts. planting and 1.5 kg per are at top-dressing). In practical terms, apply the content of 1 plastic water or soda Manure, compost and mineral fertilizer must be Use certified seed or quality seed purchased from Two ways of planting potatoes are possible: planting bottle cap per two seed tubers or plants at each mixed well with soil to avoid direct contact with known seed producers or sources. The small plot into furrows or in holes. The two methods can application. Apply 1 cap of NPK 17-17-17 per two seed planted tubers. Apply the manure or compost first, technique can be used for on-farm bulking of produce the same results. Therefore, it is up to the tubers at planting and 1 cap of NPK 17-17-17 per two then add the fertilizers, and cover with 5-10 cm of soil. high-quality seeds sourced from trusted seed farmer to choose the easiest method. Planting on plants as top-dressing 1-2 weeks after plant emer- Then place the seed potato. To fertilize the crop after producers (see Demo Guide). This will reduce ridges or beds can be considered in fields with high gence at the first weeding and hilling up. Farmers who emergence, dig one small hole at around 10-15 cm significantly the amount of high-quality seeds that risk of erosion (steep slope and high rainfall) and/or are not able to apply fertilizers after emergence, can from the plant base using a stick. Put fertilizers and need to be purchased by the farmer. If using poor drainage. Prepare furrows or holes at a spacing apply all at planting. Also, if a farmer fails to apply cover with soil using hands or the stick. farm-saved seeds, tubers harvested from healthy between rows of 70-80 cm. If your variety produces fertilizers at planting, he/she may apply all after In acidic soils (soils with a pH below 5.5), in addition looking mother plants should be used. This abundant foliage and/or the slope is steep, the emergence. to manure or compost and mineral fertilizers, lime technique is called positive selection and requires spacing between lines can be increased to 90 cm. Mineral fertilizer is best combined with manure or should be applied to avoid poor nutrient availabilities hands-on training in the field (see Demo guide). Do Within rows, use a plant spacing of 25-35 cm compost. Up to two handfuls of well decomposed and soil toxicities. Lime should be applied during land not use small potatoes from the market for seed, depending on seed size, 25 cm when tubers are manure or compost can be applied per seed tuber. This preparation at a rate of 25 to 50 kg per are (100 sqm). they are unmarketable because they are small and small (around 30 mm of diameter), 30 cm when is equivalent to around 200- 300 kg of manure or In fields where lime has been applied previously, the full of diseases. tubers are medium sized (around 40 mm) and 35 cm compost per are (100 sqm). This is very useful on poor pH of the soil should be measured at the start of Ensure the seed tubers are well sprouted with for large tubers (like 50 mm of diameter). Farmers soils. It is not recommended for rich soils such as forest subsequent seasons and lime should be re-applied uniform sprout size of around 1-2 cm. At 4 to 6 weeks should avoid cutting large seed tubers into pieces, as soils. Manure and/or compost should be applied only when the pH drops below 5.5. Either travertine or before planting, the main sprout should be taken off this may spread diseases among tubers by during land preparation or at planting. Kitchen dolomitic lime can be used, but travertine may be to promote the development of more lateral sprouts. contaminated cutting equipment. compost containing potato, tomato, eggplant, pepper more profitable as it is less expensive. The use of Avoid old and dried out tubers with long, white Note that on a sloping terrain, furrows or holes or other solanaceous crops should never be used as it acidifying mineral fertilizers such as urea, sprouts which can break off during handling. Short should run across the slope to reduce soil erosion may carry potato diseases. di-ammonium phosphate and ammonium sulphate and strong, green sprouts will ensure that once and maintain runoff water within plant rows. After should be avoided in acidic soil. planted growth will be faster, uniform and the crop planting, tubers should be covered by enough soil will be more vigorous. It is important to handle the (10-15 cm). Uncovered holes or furrows should sprouted seed tubers with care during transport, always be avoided. packing and unpacking and planting, to avoid The quantity of seeds to be used per unit of area damage to sprouts. Seed potatoes damaged by pests depends on several factors, such as planting distance or diseases should never be used for planting. Ensure and tuber size. The quantity of 2 t/ha is normally used as that seed tubers of the same size (category) are a reference, which is the quantity needed with a plant planted together in one area. This results in uniform spacing of 80x30 cm and averaged sized seed tubers of crop vegetation which will facilitate better around 50 g per tuber. This topic requires hands-on management. training in the field (see Demo Guide). A good crop starts with good seed. Plant good quality seed of market-preferred varieties. Currently, the most grown varieties in Rwanda are Sangema, Cruza, Mabondo, Victoria, Kirundo, Mizero, Kigega, Ngunda, Nderera, Gikungu, Kinigi and Twihaze. Seeds of the same variety should never be mixed. 13 Like any other crop, potato requires adequate nutrients from organic inputs (manure or compost) and/or mineral fertilizers to grow well. Nitrogen (N), phosphorus (P) and potassium (K) are the most important nutrients for a potato crop. A potato crop yielding 10 t/ha removes around 40 kg of N, 10 kg of P and 50 kg of K from the soil, and these nutrients need to be replaced to avoid soil fertility decline. N and P are important during the whole crop growth cycle, while K is most needed during tuber bulking. Depending on soil type, it may be beneficial to The best fertilizer responses can be expected when also apply secondary or micronutrients such as quantities and types of fertilizer to be applied are Ca, Mg, S and Zn. determined based on soil type and field history. This is Excessive application of fertilizers can damage called site-specific fertilizer management. Tools to provide plants and the environment and is a wastage of site-specific fertilizer recommendations based on soil money, while applying too little can result in analysis or digital soil maps are increasingly available, and plants not growing to their optimum size. farmers should seek for the best available and most Fertilization with high amounts of N containing updated recommendations at the start of each season. fertilizer should be avoided because it In case a site-specific recommendation is not available, it encourages excessive foliage growth, depressed is recommended to apply 3 kg of NPK 17-17-17 per are tuber growth and it may produce tubers with (100 sqm) divided into 2 applications (1.5 kg per are at hollow hearts. planting and 1.5 kg per are at top-dressing). In practical terms, apply the content of 1 plastic water or soda Manure, compost and mineral fertilizer must be Theme 7: Weeding and hilling bottle cap per two seed tubers or plants at each mixed well with soil to avoid direct contact with application. Apply 1 cap of NPK 17-17-17 per two seed planted tubers. Apply the manure or compost first, tubers at planting and 1 cap of NPK 17-17-17 per two then add the fertilizers, and cover with 5-10 cm of soil. plants as top-dressing 1-2 weeks after plant emer- Then place the seed potato. To fertilize the crop after gence at the first weeding and hilling up. Farmers who emergence, dig one small hole at around 10-15 cm are not able to apply fertilizers after emergence, can from the plant base using a stick. Put fertilizers and apply all at planting. Also, if a farmer fails to apply cover with soil using hands or the stick. fertilizers at planting, he/she may apply all after In acidic soils (soils with a pH below 5.5), in addition emergence. to manure or compost and mineral fertilizers, lime Mineral fertilizer is best combined with manure or should be applied to avoid poor nutrient availabilities compost. Up to two handfuls of well decomposed and soil toxicities. Lime should be applied during land manure or compost can be applied per seed tuber. This preparation at a rate of 25 to 50 kg per are (100 sqm). is equivalent to around 200- 300 kg of manure or In fields where lime has been applied previously, the compost per are (100 sqm). This is very useful on poor pH of the soil should be measured at the start of soils. It is not recommended for rich soils such as forest subsequent seasons and lime should be re-applied soils. Manure and/or compost should be applied only when the pH drops below 5.5. Either travertine or during land preparation or at planting. Kitchen dolomitic lime can be used, but travertine may be compost containing potato, tomato, eggplant, pepper more profitable as it is less expensive. The use of Good hilling Bad hilling or other solanaceous crops should never be used as it acidifying mineral fertilizers such as urea, may carry potato diseases. di-ammonium phosphate and ammonium sulphate cm. The second hilling occurs 2-3 weeks later, should be avoided in acidic soil. depending on the growth of the crop canopy. The Emphasize that hilling is one of the height of the ridge after the second hilling should be most important good agricultural about 30 cm. A third and last hilling may occur practices for better potato yields another 2-3 weeks later, especially when the slope and/or the rainfall are high. Ensure that tubers are not uncovered at any time. For potatoes that have been planted on ridges or beds, only one hilling may The potato crop should be weeded early to reduce be required. The hilling topic requires hands-on competition for light, nutrients and water from weeds, training in the field (Demo Guide). and to prevent weeds from harbouring pests and diseases. First weeding normally occurs right after When hilling, take care to avoid damaging the roots plant emergence, when the plants are about 10-15 cm and stolons. If possible, use a smaller (thinner) hoe tall. Weeds should be pulled up directly or by scraping than the one used for other field activities. them out of the soil with a hoe, collected and buried Benefits of hilling potatoes include the following: or composted. If there are not so many weeds and 1) Maintaining soft soil for smooth root, stolon and those present are not grasses, weeds can be piled up tuber development. around the plants. The field should remain free of 2) Ensuring that stolons produce tubers and weeds until the foliage dies. Avoid planting potatoes in a field where there is a weed which is difficult to preventing that stolons become above-ground control or eradicate. stems when exposed to light. 3) Facilitating nutrient uptake while reducing risks Hilling is mounding earth around potato plants when of poor drainage. they are young to ensure stolons produce tubers 4) Reducing the temperature around the growing rather than more above-ground stems. For potatoes that have been planted on flat land, two to three tubers. hilling are required. Hilling potatoes for the first time 5) Reducing tuber exposure to sunlight which turns is always done with the first weeding 2-3 weeks after the tubers green. Green tubers are NOT meant to plant emergence, especially when plants grow fast. It be eaten because they are poisonous. increases and loosens the soil around the stems, 6) Reducing exposure of tubers to pests and allowing plants to produce many tubers. The height of diseases such as potato tuber moth that can the ridge after the first hilling up should be about 15 cause huge losses in field and storage. 14 Like any other crop, potato requires adequate nutrients from organic inputs (manure or compost) and/or mineral fertilizers to grow well. Nitrogen (N), phosphorus (P) and potassium (K) are the most important nutrients for a potato crop. A potato crop yielding 10 t/ha removes around 40 kg of N, 10 kg of P and 50 kg of K from the soil, and these nutrients need to be replaced to avoid soil fertility decline. N and P are important during the whole crop growth cycle, while K is most needed during tuber bulking. Depending on soil type, it may be beneficial to The best fertilizer responses can be expected when also apply secondary or micronutrients such as quantities and types of fertilizer to be applied are Ca, Mg, S and Zn. determined based on soil type and field history. This is Excessive application of fertilizers can damage called site-specific fertilizer management. Tools to provide plants and the environment and is a wastage of site-specific fertilizer recommendations based on soil money, while applying too little can result in analysis or digital soil maps are increasingly available, and plants not growing to their optimum size. farmers should seek for the best available and most Fertilization with high amounts of N containing updated recommendations at the start of each season. fertilizer should be avoided because it In case a site-specific recommendation is not available, it encourages excessive foliage growth, depressed is recommended to apply 3 kg of NPK 17-17-17 per are tuber growth and it may produce tubers with (100 sqm) divided into 2 applications (1.5 kg per are at hollow hearts. planting and 1.5 kg per are at top-dressing). In practical terms, apply the content of 1 plastic water or soda Manure, compost and mineral fertilizer must be Theme 8: Irrigation bottle cap per two seed tubers or plants at each mixed well with soil to avoid direct contact with application. Apply 1 cap of NPK 17-17-17 per two seed planted tubers. Apply the manure or compost first, tubers at planting and 1 cap of NPK 17-17-17 per two then add the fertilizers, and cover with 5-10 cm of soil. plants as top-dressing 1-2 weeks after plant emer- Then place the seed potato. To fertilize the crop after gence at the first weeding and hilling up. Farmers who emergence, dig one small hole at around 10-15 cm are not able to apply fertilizers after emergence, can from the plant base using a stick. Put fertilizers and apply all at planting. Also, if a farmer fails to apply cover with soil using hands or the stick. fertilizers at planting, he/she may apply all after In acidic soils (soils with a pH below 5.5), in addition emergence. to manure or compost and mineral fertilizers, lime Mineral fertilizer is best combined with manure or should be applied to avoid poor nutrient availabilities compost. Up to two handfuls of well decomposed and soil toxicities. Lime should be applied during land manure or compost can be applied per seed tuber. This preparation at a rate of 25 to 50 kg per are (100 sqm). is equivalent to around 200- 300 kg of manure or In fields where lime has been applied previously, the compost per are (100 sqm). This is very useful on poor pH of the soil should be measured at the start of soils. It is not recommended for rich soils such as forest subsequent seasons and lime should be re-applied soils. Manure and/or compost should be applied only when the pH drops below 5.5. Either travertine or during land preparation or at planting. Kitchen dolomitic lime can be used, but travertine may be compost containing potato, tomato, eggplant, pepper more profitable as it is less expensive. The use of or other solanaceous crops should never be used as it acidifying mineral fertilizers such as urea, may carry potato diseases. di-ammonium phosphate and ammonium sulphate should be avoided in acidic soil. It is important to ensure that the crop will get enough water throughout the crop growth Discuss irrigation equipment or cycle. Potato needs between 500 and 800 mm infrastructure available in the area and/or of water per season to grow optimally. Potato the opportunities and needs to establish water needs are most critical at tuber initiation. sustainable irrigation systems When drought occurs at that stage, the duration of tuber formation increases which results in big yield reductions. Half of expected yield can be lost. cost-effective method. However, water flowing through the field through irrigation channels should be avoided In Rwanda it is possible to grow potatoes when bacterial wilt is present in the field, to avoid it during the dry season (from May to August), in from spreading. case water is supplied through irrigation. Farmers who can access water are encouraged When available, solar energy equipment can be to invest in irrigation systems. It is one of the considered to generate energy for pumping water from a best adaptation strategies that can reduce the water source. This can be more profitable than using fuel impact of climate change. Irrigation by gravity for pumping and will assure the crop can always be whenever possible is a reliable and irrigated when fuel is not available. 15 Theme 9: Intercropping potatoes Land preparation activities for potato cultivation severely disturb the soil, increasing the risk for Discuss with participants whether soil erosion, especially in areas with steep slopes potatoes are intercropped with other and high rainfall. Planting an intercrop between crops in the area and which intercrop rows of potato plants increases soil cover and combinations are most beneficial reduces the amount of soil lost from the field through erosion. In areas with low rainfall, the increased soil cover by an intercrop helps to Intercrops can also lead to reduced pest and disease preserve the soil moisture and prevents soil pressure in the potato crop by providing a barrier drying. In hot regions, the increased soil cover between potato plants or trapping insect pests. also reduces soil temperatures which will help In summary, intercropping potatoes with other crops can the potato plants to form more tubers. have many benefits, resulting in higher and more When potatoes are intercropped with high sustainable potato yields over time, through: nitrogen-fixing legume grain or fodder crops 1) Controlling soil erosion and reducing soil nutrient such as cowpea or lupin, the potato crop can losses. benefit from increased soil fertility through the 2) Preserving soil moisture. nitrogen fixed by the legume plants. This is 3) Optimizing soil temperatures. especially recommended on soils with low soil 4) Improving soil fertility and quality. fertility and when low to moderate rates of 5) Reducing pest and disease pressure. nitrogen fertilizer are used. It is important to carefully select the best intercrop combinations, arrangements and planting dates to avoid as much as possible competition for nutrients and water. 16 Module 3 Pest and disease management Theme 10: The disease triangle Host Disease Pathogen Environment 2) Presence of the pathogen (organism causing Engage the participants in a discussion about disease). the phenomenon of latent infection which 3) Environmental conditions that favor the spreads hidden diseases, and the importance pathogen, such as temperature and humidity of using clean seeds and crop rotation and the presence of pathogen carriers such as wind, water, farming tools or insects. A disease management strategy can be designed Like any other crop, it is important to protect potatoes by influencing or changing any one of these against pests and diseases because they reduce tuber factors, obstructing disease development. This quality and yield. The loss can be total (100%). Potato is triangle hence constitutes the base for the control especially sensitive to pests and diseases because it is a of pests and diseases. Any strategy to control vegetatively propagated crop. Diseases can break out pests and diseases should aim at breaking this when there is a favorable interaction between the harmful interaction. disease causal agent (also called the pathogen), the Please note that the pathogen can stay in the plant condition of the host plants and the environmental or tuber for a long time without symptoms, as long conditions. These three factors are related as depicted as the environmental conditions are not conducive in the DISEASE TRIANGLE. The development of a disease to the disease outbreak. This phenomenon is is stimulated by: known as latent infection which is very common 1) The host plant being in a vulnerable condition for the disease called bacterial wilt. because of a poor genetic resistance, being in a vulnerable growth stage or poor health due to inadequate nutrient management. 17 Two factors are extremely important in fighting any In general, well-nourished, vigorous plants grown on infected tubers, plant debris and soil. The disease can with different active ingredients between sprays. Do potato pest or disease: fertile soil are more resistant or tolerant to pests and spread to tubers causing them to rot with a bad smell. not mix different fungicides in a single application. 1) The use of high-quality, pest- and disease-free diseases. Therefore, integrated nutrient management Severe infections occur under wet conditions at times Pesticides have negative effects on the applicator’s seeds. ensuring a balanced supply of nutrients through of high relative humidity (over 90%). The disease health and the environment, and in addition they are 2) Crop rotation, where a potato crop is rotated for manure or compost and mineral fertilizers can help to spreads very quickly in the field and, if it is not costly. Therefore, it is important to follow a at least 2 seasons with other crops, while control the effects of pests and diseases. The use of controlled, infected plants die within a week. recommended spraying schedule for the pesticides to continuously removing potato plants sprouted organic inputs (manure or compost) also helps to from left-over tubers (volunteer potatoes) in the promote beneficial microorganisms in the soil that Late blight can be managed through: be more effective. The recommended spraying schedule against late blight is as follows: subsequent crops. Removing volunteer compete with soil-borne pathogens. 1) Planting clean seed. potatoes is crucial to avoid further buildup of 2) Use less susceptible varieties (if available). 1) Use first a contact fungicide right after plant potato pests and diseases in the field. In the following paragraphs, the manual provides emergence when the plants are around 10 cm insights on some of the most common and harmful 3) Collect and burn potato foliage after harvest. tall. The timing of this spray is very critical. It Farmers must manage pests and diseases to protect pests and diseases found in Rwanda, with specific 4) Using a wider plant spacing (lower plant density) should be early enough to avoid the young their investment in good quality seed. Even if free of recommendations on how to control them. to reduce humidity in the field. plants become infected. diseases, a crop planted with good quality seeds 5) Timely sprays of fungicides to prevent infection 2) Spray a systemic fungicide two weeks later, i.e., can become diseased with poor practices. and even kill the pathogen after infection to avert around 40-45 days after planting, if conditions are spread. highly suitable for late blight to develop (wet Theme 11: Control of late blight Several fungicides are well known to control late blight conditions and a lot of late blight in the area). when used as prescribed. Two major groups of 3) For subsequent sprays, use contact fungicides at pesticides are normally used to control this disease. 2-week intervals until the canopy turns yellow The first group contains pesticides that kill by contact due to maturity, except when disease symptoms at the plant surface (contact fungicides). An example are visible in the field. of a contact fungicide that is often used by potato 4) In case late blight symptoms are visible in the growers in Rwanda is Mancozeb. Contact fungicides field, spray a systemic fungicide. Once disease are effective early in the season to avoid infection and symptoms have disappeared, return to spraying at especially when a lot of rain is expected, but are 2-weeks intervals with a contact fungicide. ineffective once plants are infected. The second group In principle, less susceptible varieties should not be comprises fungicides known as systemic fungicides sprayed more than twice in a season with systemic because they enter the plant and move inside the pesticides because of their cost and potential to plant and kill the pathogen. These fungicides are used induce pathogen resistance and cause harm to the later in the season to fight the disease while it has environment. already infected plants and symptoms have been For each spray, use the dosage that is recommended noticed. However, systemic fungicides can also be by the manufacturer. Please note that exceeding the used early in the season when conditions are highly prescribed dose does not provide any additional suitable for late blight to develop (a lot of rain, and a benefit but rather unwanted negative side effects. lot of late blight present in the area and air). An Contact fungicides (such as Mancozeb) should be example of a systemic fungicide that is often used by applied at least 6 hours before it rains to avoid the potato growers in Rwanda is Ridomil. fungicides to be washed away. Systemic fungicides It is important not to always use the same fungicide (such as Ridomil) should be applied at least 3 hours because in that case the fungicide may no longer be before it rains. The leaves need to be dry before Late blight is a fungal disease that causes crop effective for managing the disease. Therefore, it is spraying (no dew on the leaves). Spraying should not failure by damaging the leaves, stems and tubers. important to alternate the use of different fungicides be done around midday when there is too much sun. Infected leaves or stems have grey/brown/black Emphasize the importance of using clean spots as if they were burned. Late blight also seeds and varieties that are less susceptible causes yellowing at the edges and white fluffy to late blight. Discuss with farmers which mycelium strands at the undersides of the leaves. varieties with good resistance against late Late blight is transmitted by fungal spores which blight are available in the area are spread by wind and water and persist in 18 infected tubers, plant debris and soil. The disease can with different active ingredients between sprays. Do spread to tubers causing them to rot with a bad smell. not mix different fungicides in a single application. Severe infections occur under wet conditions at times Pesticides have negative effects on the applicator’s of high relative humidity (over 90%). The disease health and the environment, and in addition they are spreads very quickly in the field and, if it is not costly. Therefore, it is important to follow a controlled, infected plants die within a week. recommended spraying schedule for the pesticides to Late blight can be managed through: be more effective. The recommended spraying schedule against late blight is as follows: 1) Planting clean seed. 2) Use less susceptible varieties (if available). 1) Use first a contact fungicide right after plant emergence when the plants are around 10 cm 3) Collect and burn potato foliage after harvest. tall. The timing of this spray is very critical. It 4) Using a wider plant spacing (lower plant density) should be early enough to avoid the young to reduce humidity in the field. plants become infected. 5) Timely sprays of fungicides to prevent infection 2) Spray a systemic fungicide two weeks later, i.e., and even kill the pathogen after infection to avert around 40-45 days after planting, if conditions are spread. highly suitable for late blight to develop (wet Several fungicides are well known to control late blight conditions and a lot of late blight in the area). when used as prescribed. Two major groups of 3) For subsequent sprays, use contact fungicides at pesticides are normally used to control this disease. 2-week intervals until the canopy turns yellow The first group contains pesticides that kill by contact due to maturity, except when disease symptoms at the plant surface (contact fungicides). An example are visible in the field. of a contact fungicide that is often used by potato 4) In case late blight symptoms are visible in the growers in Rwanda is Mancozeb. Contact fungicides field, spray a systemic fungicide. Once disease are effective early in the season to avoid infection and symptoms have disappeared, return to spraying at especially when a lot of rain is expected, but are 2-weeks intervals with a contact fungicide. ineffective once plants are infected. The second group In principle, less susceptible varieties should not be comprises fungicides known as systemic fungicides sprayed more than twice in a season with systemic because they enter the plant and move inside the pesticides because of their cost and potential to plant and kill the pathogen. These fungicides are used induce pathogen resistance and cause harm to the later in the season to fight the disease while it has environment. already infected plants and symptoms have been For each spray, use the dosage that is recommended noticed. However, systemic fungicides can also be by the manufacturer. Please note that exceeding the used early in the season when conditions are highly prescribed dose does not provide any additional suitable for late blight to develop (a lot of rain, and a benefit but rather unwanted negative side effects. lot of late blight present in the area and air). An Contact fungicides (such as Mancozeb) should be example of a systemic fungicide that is often used by applied at least 6 hours before it rains to avoid the potato growers in Rwanda is Ridomil. fungicides to be washed away. Systemic fungicides It is important not to always use the same fungicide (such as Ridomil) should be applied at least 3 hours because in that case the fungicide may no longer be before it rains. The leaves need to be dry before Late blight is a fungal disease that causes crop effective for managing the disease. Therefore, it is spraying (no dew on the leaves). Spraying should not failure by damaging the leaves, stems and tubers. important to alternate the use of different fungicides be done around midday when there is too much sun. Infected leaves or stems have grey/brown/black spots as if they were burned. Late blight also causes yellowing at the edges and white fluffy mycelium strands at the undersides of the leaves. Late blight is transmitted by fungal spores which are spread by wind and water and persist in 19 Theme 12: Control of bacterial wilt 4) Using compost that is not infected with technique is called roguing (see Demo Guide). Do bacterial wilt. not put infected plants into compost. Lime or 5) Uprooting wilting plants together with soil kitchen ash can be applied in the hole where the around roots. The uprooted plants with soil plant was uprooted to kill the disease. should be collected in a bag or basket, brought 6) Cleaning and/or disinfecting farming tools like hoes away from the potato field, thrown in a deep pit before and after use to avoid spreading the away from agricultural fields, and burnt. This infection (with fire or disinfectant like Jik). Contamination Bacterial wilt causes partial to complete wilting of a plant even if there is enough water in the soil. In partial wilting, only a few stems wilt and the rest Emphasize that bacterial wilt can spread of the plant appears healthy. Early in infection, the through seeds, soil, water farming tools, plant will recover overnight and later in infection, livestock and people. Also, it is worth the plant does not recover. When an infected mentioning that not every case of wilting tuber is cut in half, black or brown rings can be in the field is caused by bacterial wilt. It is seen. Sometimes, a milk like fluid comes out of advised to conduct the glass test in the tuber eyes signified by soil sticking to tuber eyes field (see Demo Guide) at harvest. Bacterial wilt can infect the crop at all crop stages and can cause total failure of the crop. It is both a soil and seed borne disease. The pathogen can The disease can spread from field to field or from plant survive in the soil for many years. to plant within a field via infected seed, water, soil, farming tools, livestock and people. Plants and tubers can be infected but not show symptoms, this is called latent infection. Using There is no commercial chemical for controlling tubers from such plants can spread the disease. bacterial wilt. Therefore, the only way is to manage the Bacterial wilt also affects plants from the same disease through cultural practices which include the family as potato such as chili, pepper, tomato, following: tobacco, and eggplant, as well as several weed 1) Planting clean seed in fields free from bacterial wilt. species. It can be detected in the plant by 2) Use less susceptible varieties. immersing a small piece of stem base in a glass of 3) Rotating potato crops for at least 2-4 seasons with water (see Demo Guide). Bacterial wilt has the other crops not belonging to the potato family, such exclusive property of oozing from the stem and as cereals and legumes. moving downward in the water. 20 4) Using compost that is not infected with technique is called roguing (see Demo Guide). Do bacterial wilt. not put infected plants into compost. Lime or 5) Uprooting wilting plants together with soil kitchen ash can be applied in the hole where the around roots. The uprooted plants with soil plant was uprooted to kill the disease. should be collected in a bag or basket, brought 6) Cleaning and/or disinfecting farming tools like hoes away from the potato field, thrown in a deep pit before and after use to avoid spreading the away from agricultural fields, and burnt. This infection (with fire or disinfectant like Jik). Theme 13: Control of soft rot (or blackleg) Bacterial wilt causes partial to complete wilting of a plant even if there is enough water in the soil. In partial wilting, only a few stems wilt and the rest of the plant appears healthy. Early in infection, the plant will recover overnight and later in infection, the plant does not recover. When an infected tuber is cut in half, black or brown rings can be seen. Sometimes, a milk like fluid comes out of tuber eyes signified by soil sticking to tuber eyes at harvest. Bacterial wilt can infect the crop at all crop stages Soft rot, also known as blackleg, is caused by a and can cause total failure of the crop. It is both a bacterium which has the characteristic of altering soil and seed borne disease. The pathogen can The disease can spread from field to field or from plant It is important to mention that even tuber tissue into liquid or soft rot. The symptoms survive in the soil for many years. to plant within a field via infected seed, water, soil, though soft rot is a harmful disease, it is on the plants are concentrated around the lower farming tools, livestock and people. Plants and tubers can be infected but not show not widely spread like bacterial wilt. stem region, causing black lesions at the base of symptoms, this is called latent infection. Using There is no commercial chemical for controlling Emphasize the difference between the the stem. tubers from such plants can spread the disease. bacterial wilt. Therefore, the only way is to manage the two diseases Infected tubers rot either in the field or in storage Bacterial wilt also affects plants from the same disease through cultural practices which include the and produce a bad smell. High soil moisture favors family as potato such as chili, pepper, tomato, following: the pathogen to attack tubers and stems, causing tobacco, and eggplant, as well as several weed 1) Planting clean seed in fields free from bacterial wilt. significant crop losses. species. It can be detected in the plant by 2) Use less susceptible varieties. The disease is spread in similar ways as bacterial immersing a small piece of stem base in a glass of 3) Rotating potato crops for at least 2-4 seasons with wilt. The disease can therefore be managed by water (see Demo Guide). Bacterial wilt has the other crops not belonging to the potato family, such applying the same control measures exclusive property of oozing from the stem and as cereals and legumes. recommended for bacterial wilt. moving downward in the water. 21 Theme 14: Control of viral diseases 4) Clean and/or disinfect farming tools like hoes before and whiteflies are carriers of viruses. Therefore, and after use to avoid spreading the infection (e.g. fire management of these insects by spraying or Jik can be used). insecticides, and/or trapping them reduces the 5) Keeping the field and its surrounding area free of spread of viral diseases. Note that insecticides weeds because they can host viruses that infect potato. are harmful to human health and the 6) Controlling insects that can spread viral diseases. environment and should only be used as a last Sucking insects such as aphids, thrips, mites, leafminers resort in severe cases. One of the potato viral diseases that can be easily detected is potato leafroll virus. Plants infected by this virus show leaflets curling upward and turning pale Recognizing viruses is hard for farmers. yellow and when pressed they feel brittle and fragile. Therefore, visiting potato fields and showing some of the symptoms can be Another virus that can be recognized relatively insightful easily is the mosaic virus. Diseased leaflets appear translucent and yellowish (see Demo Guide). There are many types of viruses and in most cases the field or the plant is infected by more than one A common problem when cultivating potatoes is virus causing compound effects. Since there are no reduced yield from one generation of seeds to the next. specific control strategies for each virus, do not This yield reduction is often caused by viral infections blame yourself for not knowing the different residing in the seed tubers due to farmers’ habit of viruses. What is important is to be able to selecting small tubers to be used as seeds. Generally, differentiate a normal (healthy looking) plant from viral diseases lead to smaller potato tubers. a diseased one. Consequently, when tubers are sorted and selected for Viruses are controlled by the combination of the seed based on size, many selected tubers are those following practices: infected with viral diseases. 1) Using clean seed. It is very risky to select seed Viral diseases are difficult to recognize in the field. In the potatoes based on tuber size (selecting small case of mild infections, the plants can show no signs of tubers as seed potatoes), as plants infected with disease at all. viral diseases generally produce smaller tubers. Viral infections rarely cause plants to die. The symptoms, 2) Planting potato varieties that are less if any at all, are changes in the shape of plants. These susceptible to viral diseases. include distorted and bubbling leaves, short and bunchy 3) Uproot and remove infected plants from the plants (dwarfing), leaf curl, and yellow veins and field (roguing) and burn them in a deep pit. Do yellowing of the leaves. not put infected plants into compost. 22 4) Clean and/or disinfect farming tools like hoes before and whiteflies are carriers of viruses. Therefore, and after use to avoid spreading the infection (e.g. fire management of these insects by spraying or Jik can be used). insecticides, and/or trapping them reduces the 5) Keeping the field and its surrounding area free of spread of viral diseases. Note that insecticides weeds because they can host viruses that infect potato. are harmful to human health and the 6) Controlling insects that can spread viral diseases. environment and should only be used as a last Sucking insects such as aphids, thrips, mites, leafminers resort in severe cases. Theme 15: Control of potato tuber moth One of the potato viral diseases that can be easily detected is potato leafroll virus. Plants infected by this virus show leaflets curling upward and turning pale yellow and when pressed they feel brittle and fragile. Another virus that can be recognized relatively easily is the mosaic virus. Diseased leaflets appear translucent and yellowish (see Demo Guide). There are many types of viruses and in most cases the field or the plant is infected by more than one Potato tuber moth can be controlled by: A common problem when cultivating potatoes is virus causing compound effects. Since there are no reduced yield from one generation of seeds to the next. specific control strategies for each virus, do not 1) Avoiding planting in too light and loose soil, as This yield reduction is often caused by viral infections blame yourself for not knowing the different Emphasize the importance of good hilling this facilitates exposure of tubers on which the residing in the seed tubers due to farmers’ habit of viruses. What is important is to be able to and avoiding cracks in the soil at tuber female moths can deposit their eggs. selecting small tubers to be used as seeds. Generally, differentiate a normal (healthy looking) plant from bulking that expose stage tubers 2) High hilling to protect tubers. Avoid tubers to be viral diseases lead to smaller potato tubers. a diseased one. exposed to the air through cracks in the soil. Consequently, when tubers are sorted and selected for 3) Avoid storing tubers showing Viruses are controlled by the combination of the seed based on size, many selected tubers are those openings/galleries and/or excreta. Moths in following practices: infected with viral diseases. Potato tuber moths (PTM), also called potato tuber storage can cause huge damage to other 1) Using clean seed. It is very risky to select seed worms, infest the crop in the field and move with tubers tubers and neighboring fields. Viral diseases are difficult to recognize in the field. In the potatoes based on tuber size (selecting small to the store. Moth larvae penetrate tubers through the 4) Using natural repellent plants such as Lantana case of mild infections, the plants can show no signs of tubers as seed potatoes), as plants infected with eyes and create tunnels (galleries) in the tubers. The and Eucalyptus that cause moths to fly away disease at all. viral diseases generally produce smaller tubers. larvae can also create mines in the stems. They from the storage place. Viral infections rarely cause plants to die. The symptoms, 2) Planting potato varieties that are less reproduce continuously in stored potatoes causing 5) Spraying the field with appropriate insecticides. if any at all, are changes in the shape of plants. These susceptible to viral diseases. huge losses. In the stores, infected tubers become drier Note that insecticides are harmful to human include distorted and bubbling leaves, short and bunchy 3) Uproot and remove infected plants from the than healthy ones. health and the environment and should only plants (dwarfing), leaf curl, and yellow veins and field (roguing) and burn them in a deep pit. Do be used as a last resort in severe cases. yellowing of the leaves. not put infected plants into compost. 23 Theme 16: Control of nematodes Potato plants infested with nematodes may show varying degrees of stunting, yellowing of leaves and a tendency to wilt under moisture stress. Two The topic of nematodes is not easy to types of nematodes are known in potato explain unless you have some samples production: the root-knot nematodes and the for illustration potato cyst nematodes. Root-knot nematodes are the most widely spread across the globe. They attack tubers and cause Management of nematodes should focus on reducing blemishes making tubers unmarketable. Potato the population to levels below the damaging threshold. plants infested with root-knot nematodes can Control of nematodes is primarily preventive because become more susceptible to bacterial wilt. they are difficult to eradicate once they are present in Damage from cyst nematodes is shown by the field. Management practices include: expanding patches in the field of plants with poor 1) Selecting non-infested fields for production. growth. The plants are stunted, yellow or 2) Using clean seed potatoes. Never use seed potatoes yellow-white and wilting. This eventually leads to harvested from an infected field. reduced yields and small tubers. Twenty years may 3) Once nematodes are present in the field, wait 5 elapse from the nematode introduction in a field years before planting potato in the field again while until field symptoms become obvious. Note that it avoiding crops from the same family, e.g., tomato, is safe to eat potatoes containing nematodes. eggplant, chili. Never use tubers that are infested with nematodes for seed. 4) Cultivating potato varieties that are less susceptible to nematodes. 24 Theme 17: Safe use of pesticides negative impacts on human health and the environment: It is important to emphasize that pesticides have both wanted and unwanted effects. 1) Always read the instructions given by the Engage trainees in a moderated discussion manufacturer on the label. on the advantages and disadvantages and 2) Do not spray more than the dose good and bad practices related to the use recommended by the manufacturer. of 3 pesticides 3) Wear protective gear, including a work suit covering arms and legs, a mask, boots and gloves. 4) Avoid time of strong wind and do not spray Pesticides (this includes fungicides, insecticides and against wind direction. herbicides) should be used carefully to avoid harm to 5) Spraying of pesticides should never be done the user and neighbors’ health, and the environment. by pregnant women or kids. Pregnant women All pesticides are harmful to people and the and kids should not enter a field during or environment and should be handled with much care. within a few days after spraying. There are many cases of pesticide poisoning in farming 6) Never spray crops just before harvest. This is communities. Pesticides should therefore be the last strictly forbidden and very harmful for the resort after the farmer has exhausted other cultural or consumers. No fungicides or insecticides biological control mechanisms such as varieties with should be applied during the last 3 weeks of pest/disease resistance, use of healthy seed potatoes, the crop cycle. rotation with other crops, organic pesticides (e.g., 7) Keep pesticides in a safe place where they are neem) and integrated soil management. out of reach by children and far from food or The aim of pesticide use is to maintain pest populations places in the house where food is prepared. and disease severity at acceptable levels while keeping 8) Do not dispose leftovers of pesticide solutions pesticide use and related interventions to levels that are in the environment. Never dispose pesticide economically justified and safe for human health and leftovers in water bodies where water may be the environment. sourced for home use. When the use of pesticides is unavoidable, the 9) Safely dispose empty pesticide containers; do following guidelines should be respected to avoid not re-use them for other purposes. 25 labour-intensive, but produces good quality and dry out and fall off. However, the tubers should not Module 4 Post-maturity practices undamaged tubers. Using a hoe is less time- be left in the full sun for more than the time consuming and labour-intensive, but some tubers can required to dry (2 hours at most but ideally less). Theme 18: Harvesting be damaged in the process. Use of a motocultivator or After harvest, you should sanitize the field by tractor is a by far less labour-intensive and faster gathering and destroying harvest remnants such as method than harvesting manually, especially when the foliage residues and rotten tubers. This is an field is relatively big (over 1 ha). important part of controlling various pests and To avoid damage, do not throw tubers from a distance. diseases, by removing sources of contamination for After digging up the tubers, they should be left on the the next crop. ground for a while to allow any soil caked on them to Harvest should be done when the crop is well mature, at complete death of the foliage, and when the tubers' skin is firm and cannot be A farmer does not wake up and start removed by lightly rubbing the tubers with your harvesting a potato field. There is a fingers. It is recommended to dehaulm plants whole planning process to get ready for 10-15 days before harvest. Dehaulming is the logistics to get potatoes to the removing or destroying the shoots above the soil market. Huge losses can occur between ahead of the complete maturity of the plant (see harvest and sale Demo Guide). Dehaulming is essential if potatoes are to be stored as this allows the skin to harden to protect from handling and transport injury, as well as postharvest diseases. on. Timely harvesting can help avoid serious pests and Harvesting should be done in dry weather and disease damage. not when it is raining, as harvesting in the rain Harvest methods can affect tuber quality. It is important might cause tubers to rot. Harvest should be to dig up gently the potatoes to avoid wounding the done gradually from one side of the field to the tubers. Potatoes can be harvested either manually or other in a way that when it is about to rain using machinery. When harvesting manually, there are farmers can stop and start collecting harvested two ways: harvesting directly by hand or by using a hoe. tubers to avoid the harvested tubers are rained Harvesting by hand takes longer and is more 26 labour-intensive, but produces good quality and dry out and fall off. However, the tubers should not undamaged tubers. Using a hoe is less time- be left in the full sun for more than the time consuming and labour-intensive, but some tubers can required to dry (2 hours at most but ideally less). be damaged in the process. Use of a motocultivator or After harvest, you should sanitize the field by tractor is a by far less labour-intensive and faster gathering and destroying harvest remnants such as method than harvesting manually, especially when the foliage residues and rotten tubers. This is an field is relatively big (over 1 ha). important part of controlling various pests and To avoid damage, do not throw tubers from a distance. diseases, by removing sources of contamination for After digging up the tubers, they should be left on the the next crop. ground for a while to allow any soil caked on them to Theme 19: Sorting and grading tubers for the market Harvest should be done when the crop is well mature, at complete death of the foliage, and when the tubers' skin is firm and cannot be removed by lightly rubbing the tubers with your fingers. It is recommended to dehaulm plants 10-15 days before harvest. Dehaulming is removing or destroying the shoots above the soil ahead of the complete maturity of the plant (see Demo Guide). Dehaulming is essential if Not all tubers are appropriate for processing. potatoes are to be stored as this allows the skin Emphasize the need to grade and package Only large tubers (over 60 mm) are normally used to harden to protect from handling and tubers for price differentiation for making chips or crisps. transport injury, as well as postharvest diseases. on. Timely harvesting can help avoid serious pests and The cheating practice of displaying large Harvesting should be done in dry weather and disease damage. tubers at the top of bags while hiding small not when it is raining, as harvesting in the rain Harvest methods can affect tuber quality. It is important Tubers from diseased plants must be harvested and ones at the bottom and/or stuffing bags might cause tubers to rot. Harvest should be to dig up gently the potatoes to avoid wounding the collected last, and kept aside. This practice is called should be discouraged. Also, the use of bucket done gradually from one side of the field to the tubers. Potatoes can be harvested either manually or sorting. Tubers from healthy plants should be graded, as a metric for transactions may result in other in a way that when it is about to rain using machinery. When harvesting manually, there are which means separating big tubers from medium-sized malpractices. The use of scales for measuring farmers can stop and start collecting harvested two ways: harvesting directly by hand or by using a hoe. and small ones. In principle, the farmer should consider potato quantities is the method that instils tubers to avoid the harvested tubers are rained Harvesting by hand takes longer and is more the different tuber size classes when establishing prices, trust between seller and buyer. depending on what the market demands. 27 Theme 20: Storage of ware potatoes Pests and diseases that can affect tubers in storage Plants such as Lantana and Eucalyptus are natural are potato tuber moths, bacterial rot and mold. repellents of potato tuber moths and cause moths These pests and diseases are brought in the store by to fly away from the storage place. These plants can the tubers themselves or caught from other affected be planted around the store or their leaves or tubers. Routine observations should be made branches can be used to cover the potatoes. When looking for infested tubers. Infested tubers should covering the potatoes with branches of any plant be removed from the store and destroyed. material, it is important to make sure the tubers can still breath and humidity does not become too high under the branches as this will cause rotting. Often, farmers do not care much about storing ware potato like they do for seed potatoes. Engage participants in a discussion on However, properly storing ware potatoes can help the different modes of storage of farmers to preserve food for home consumption potatoes, for both home consumption for a longer time, or to get a higher price for the and sale ware potatoes when the main harvest season has passed. Only good quality potatoes should be stored. Any potatoes that are rotting, damaged or coming the doors during the day. However, doors may be from diseased fields should be eaten or sold at opened during cooler nights to allow ventilation. Lack harvest. Storing only a few rotten potatoes can of aeration causes tubers to rot. Use a 'type of material result in spread to other tubers and great losses in for the roofing that will help to maintain cool storage. temperatures inside the store during the day. Tubers for home consumption or sale can be stored There is no harm in storing ware potatoes in bulk on for a long time while maintaining good tuber the floor provided there is a minimum of hygiene. quality when the following three major conditions However, storing potatoes on racks or in crates are met: cool temperatures (below 20°C), darkness, improves ventilation. The use of the crates will limit the and ventilation. Tubers exposed to direct sunlight spread of rot to more potatoes in the store when a or high temperatures can become green and rotten potato is in the crate. Potatoes should only be poisonous, shrivel and start sprouting. To maintain stored in bags for short term storage (maximum 3 cool temperature and darkness in the store, close weeks) as bags restrict air flow and promote rotting. 28 Pests and diseases that can affect tubers in storage Plants such as Lantana and Eucalyptus are natural are potato tuber moths, bacterial rot and mold. repellents of potato tuber moths and cause moths These pests and diseases are brought in the store by to fly away from the storage place. These plants can the tubers themselves or caught from other affected be planted around the store or their leaves or tubers. Routine observations should be made branches can be used to cover the potatoes. When looking for infested tubers. Infested tubers should covering the potatoes with branches of any plant be removed from the store and destroyed. material, it is important to make sure the tubers can still breath and humidity does not become too high under the branches as this will cause rotting. Often, farmers do not care much about storing ware potato like they do for seed potatoes. However, properly storing ware potatoes can help farmers to preserve food for home consumption for a longer time, or to get a higher price for the ware potatoes when the main harvest season has passed. Only good quality potatoes should be stored. Any potatoes that are rotting, damaged or coming the doors during the day. However, doors may be from diseased fields should be eaten or sold at opened during cooler nights to allow ventilation. Lack harvest. Storing only a few rotten potatoes can of aeration causes tubers to rot. Use a 'type of material result in spread to other tubers and great losses in for the roofing that will help to maintain cool storage. temperatures inside the store during the day. Tubers for home consumption or sale can be stored There is no harm in storing ware potatoes in bulk on for a long time while maintaining good tuber the floor provided there is a minimum of hygiene. quality when the following three major conditions However, storing potatoes on racks or in crates are met: cool temperatures (below 20°C), darkness, improves ventilation. The use of the crates will limit the and ventilation. Tubers exposed to direct sunlight spread of rot to more potatoes in the store when a or high temperatures can become green and rotten potato is in the crate. Potatoes should only be poisonous, shrivel and start sprouting. To maintain stored in bags for short term storage (maximum 3 cool temperature and darkness in the store, close weeks) as bags restrict air flow and promote rotting. 29 APPENDICES Appendix 1: Guiding questions and take-home messages per figure Theme Topic Guiding questions Take home message • Where does the potato crop come from? The income generated by • Name the only two crops that are growing potatoes is often 1 Importance of the potato crop produced more than potato for higher compared to the one food production in the world? obtained from other food • Why is the potato considered to crops. be an important crop? • What are the five stages of the This stage of sprout potato crop cycle? development and Understanding • Which factors affected the emergence is critical because 2 the crop cycle length of the growth stages? the harvest is strongly of potato • When is it appropriate to harvest related to the number of the potato field? stems per seed. • What are the suitable climatic conditions for growing potatoes? • Is it advisable to plant potatoes It is highly recommended to 3 Land selection where you have harvested potatoes wait at least 2 seasons before and crop rotation or crops of the same family during you plant again potatoes or the previous season? Why? alike in the same field. • What are the crops of the same family as potato grown in your area? • Up to what depth (at least) do you need to dig the soil during land Land preparation and why? The use of motocultivators 4 preparation • What are the different steps in land or tractors can reduce the preparation for potato cultivation? burden of land preparation • Under which conditions should ridging be considered? 30 Theme Topic Guiding questions Take home message • Why is it important to get a site-specific fertilizer recommendation? Application of • What are the mineral fertilizers that are Planting potatoes on a poor 5 manure, compost recommended for the potato crop in soil without manure and and mineral your area? At which dose? mineral fertilizers is a waste fertilizers • What is the quantity of organic manure of time and resources. recommended to fertilize potatoes on an area of 1 are (100 sqm)? • What are the names of the potato Potato variety, seed tuber varieties that are grown in your areas? size, and slope are important Planting • How would you arrange plant rows 6 techniques factors to take into on a sloping terrain? consideration when • What is the optimal plant spacing for arranging seed at planting. a maximum yield in ware potatoes? • Why must a potato field remain clean, Unlike other crops such without weeds, until the harvest? as cereals, potato yield is 7 Weeding and hilling • Why is it important to hill potatoes? underground. You should • When should potatoes be hilled? not cultivate potatoes without hilling. • At which plant growth stage of potato are water needs most critical? Please ensure that there will • What can you do if you wish to plant be enough rain or irrigation 8 Irrigation potatoes in a dry season? water until the end of the • What would you do if you have to season prior to planting use a pump to irrigate your field in potatoes. an area where fuel is not available? • What is the benefit of intercropping potatoes in areas with steep slope When intercropping potato and high rainfall? with other crops, the type of 9 Intercropping • Which intercrops can be good- intercrops, planting dates potatoes choices on soils with poor soil and crop arrangement fertility? should be carefully chosen to • What are the benefits of inter- avoid competition for cropping potatoes in hot areas? resources between crops. 31 Theme Topic Guiding questions Take home message • Why is it important to control pests Being able to differentiate and diseases? diseased plants and tubers from • What are the three components of a 10 The disease healthy- looking ones (in field triangle disease triangle? and storage) is an important • How do you call an infection of the step towards controlling pests potato plant or tubers that does not and diseases. show symptoms? • What are the key symptoms of late blight in the field? And what are the Late blight is the most key conditions for its outbreak? damaging foliage potato Control of 11 late blight • What are the most effective measures disease. Ensure that you have to control late blight in the field? access to clean seeds and • What is the difference between a know how to manage the contact and a systemic fungicide? disease before planting. • What are the symptoms of bacterial There is no commercial wilt on the plant and the tubers? chemical to control bacterial 12 Control of • How can you detect bacterial wilt in bacterial wilt wilt. It is difficult to eradicate the field? the disease once present in • What are the most effective measures the soil. to control bacterial wilt? • What is potato soft rot (blackeg) and what are the symptoms? There is no commercial • How would you differentiate soft rot Control of soft chemical to control soft rot 13 (blackleg) from bacterial wilt on rot (blackleg) (blackleg). It is difficult to tubers and plants? eradicate the disease once • What are the most effective measures present in the soil. to control soft rot (blackleg)? • Why does the negative impact of viral diseases often go beyond the first season symptoms are observed No need to know the names in the field? of viruses. What is important 14 Control of viral diseases • What are the most effective measures is to be able to differentiate a to control viral diseases? normal (healthy looking) • Why is it important not to select plant from a diseased one. seeds only based on size? 32 Theme Topic Guiding questions Take home message • What is potato tuber moth (PTM)? • What are the symptoms of PTM on Planting a repellent plant 15 Control of potato tubers in storage? around the potato store such as tuber moth • What are the most effective measures Lantana can help to reduce the to control PTM in storage? impact of potato tuber moth. • What is potato nematode? Nematodes are hard to eradicate once introduced 16 Control of • What are the symptoms of nematodes nematodes on tubers? in the soil. Preventive • What are the most effective measures are always the measures to control nematodes? most effective approach. • Why is it so important to be careful when using pesticides? Please ONLY spray when 17 Safe use of • Where can you get specific necessary without exceeding pesticides indications on how to use a pesticide? the recommended dose and • How should you protect yourself and frequency. your family from the harmful effects of pesticides? • When is the right time to harvest a potato field for maximum tuber yield? Never harvest before complete death of shoots 18 Harvesting • What are the different techniques used to harvest potatoes in the field? if you wish to have a maximum yield. • Does the potato field require any care after harvest? Why? 33 Theme Topic Guiding questions Take home message • Why is it important to sort potatoes All potato tubers harvested in after harvest? the field are not intended for • Why is it important to grade tubers the same uses, and thus do 19 Sorting and after harvest? grading tubers not all have the same value. for the market • What are the possible consequences Please grade your tubers and of using buckets instead of a scale price them differently, while selling potatoes? whenever possible. • Does it make any sense to care about storage of ware potatoes? Why? Never eat or sell for • What are the best conditions for a consumption green tubers 20 Storage of ware potatoes longer shelf-life of ware potatoes? or tubers presenting green • Why is it recommended not to spots. They are poisonous. expose ware potatoes to sunlight for too long? 34 Appendix 2: Test sample for pre- and post-training knowledge assessment Assessment on ware potato production Name: Date: Note: Each good response equals 1 point out of 20 Module 1 Introduction to the potato crop 1. What are the five stages of the potato’s crop cycle? Module 2 Soil, crop and water management 2. What are the suitable climatic conditions for growing potatoes? 3. Why is it important to rotate potato with other crops? 35 4. What are the mineral fertilizers that are recommended for potato crop in your area? At which dose? 5. What is the optimal plant spacing for a maximum yield in ware potatoes? 6. Why is it important to hill potatoes? 7. At what stage of plant growth and development are water needs most critical? 8. What are the potential benefits of intercropping potato with other crops? Module 3 Pest and disease management 9. What are the three components of the disease triangle? 10. What is the difference between a contact and a systemic fungicide? 36 11. What are the most effective measures to control bacterial wilt? 12. How would you differentiate soft rot (blackleg) from bacterial wilt on tubers and plants? 13. What are the most effective measures to control viral diseases? 14. What are the symptoms of potato tuber moth on tubers in storage? 15. What are the symptoms of nematodes on tubers? 16. When is the use of pesticides strictly forbidden in a potato field, and why? 37 Module 4 Post-maturity practices 17. When is the right time to harvest a potato field for maximum tuber yield? 18. Why is it important to grade tubers after harvest? 19. What are the best conditions for a longer shelf life of ware potatoes? 20. Why is it recommended not to expose ware potatoes to the sunlight for a long time? 38