Beans under phosphate stress
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CTA. 1988. Beans under phosphate stress. Spore 13. CTA, Wageningen, The Netherlands.
Permanent link to this item: http://hdl.handle.net/10568/44792
One of the most important factors limiting bean production in the tropical acid soils of Africa is the low level of phosphorus (P). This deficiency results from overcropping without the use of fertilisers and the high fixation of P by minerals in...
One of the most important factors limiting bean production in the tropical acid soils of Africa is the low level of phosphorus (P). This deficiency results from overcropping without the use of fertilisers and the high fixation of P by minerals in the soil. To overcome this, scientists are trying to identify and develop varieties that are better able to tolerate low P conditions. This approach requires minimal investment by the farmer, and avoids the changes in infrastructure required when a new fertiliser is introduced, or the extensive training required when cultural practicas are chanaed. Twenty-nine lines of the Carioca variety grain types were selected for experimentation as they are widely variable in adapting to soils with low P levels. Absorption of P, rates of growth and yield were all measured over time for each line grown under both P stressed and non-stressed conditions. Lines were then rated as either efficient or inefficient, based on their yields under P stress. The results of the experiment suggest that the difference between efficient and inefficient plants lies less in the rates of P absorption (indeed efficient plants appear initially to absorb P more slowly) than in how they use whatever P is available. Apparently, inefficient plants abort more pods and seeds because they fail to use P that remains in stems and leaves - thus it is the ability of the plant to produce pods and seeds under P stress that is the most important characteristic of a plant that is P efficient. In the trials, efficient plants produced 6% more pods, 12% more seeds per pod and grain weight was 9% higher than that for inefficient plants. Source: Bean newsletter Volume 9 No. 1 July 1987 For more details, contact: CIAT Apartado Aereo 6713 Cali COLOMBIA