SEED TREATMENT 
TECHNOLOGIES 
FOR IMPROVED COMMON 
BEANS PRODUCTION
Authored by: Boaz Waswa, 
Eliezah Kamau and David Karanja
Introduction
Seeds saved by farmers may be infected with microbes that can induce diseases on 
the seedling and the crop. This can affect seed germination and may be transmitted 
from seed to seedling to plant.
Seed treatment prevents and controls seed-, soil-, and air-borne diseases. It improves 
germination, vigor, and productivity.
What is seed treatment?
Seed treatment or dressing refers to the application of biological, physical, and chemical 
agents and techniques to seed to provide protection and improve the establishment 
of healthy crops. 
Seed treatment may involve use of fungicide, insecticide, or a combination of both, 
applied to the seeds to disinfect them from seed-borne or soil-borne pathogenic or-
ganisms and storage insects.
Seed treatment is like immunization – it provides a good insurance and protection of 
your seed and crop against diseases, seed-borne or soil-borne pathogenic organisms 
and storage insects.
Benefits of Seed Treatment:
♦ Protects germinating seed and seedlings against soil and seed borne pest and diseases
♦ Improves germination process and increases germination percentage
♦ Enhances the seed viability and vigor
♦ Results in early and uniform establishment and growth of the crop or plants
♦ Stimulates root development leading to vigorous start, uniform growth and higher 
yields
♦ Enhances nodulation in legume crops
♦ Enhances the tolerance of plant for any unfavorable conditions.
♦ Is environmentally friendly. It decreases the number of spray applications of 
agrichemical products and lessening exposures to non-target species including 
humans and pollinators.
♦ It is a cost-effective technology for smallholder farmers with limited resources
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Bean Pest and Diseases controlled by seed 
treatment
Leaf-feeders Pests
(Flea beetle) ♦ Bean Fly
♦ Whitefly
♦ Thrips
Fruit-feeders ♦ Aphids
(Stink Bugs) ♦ Root worms
♦ Grabs
♦ Termites
Stem-feeders
(Aphids) ♦ Nematodes
♦ Harmful bacteria and fungi
Seed-feeders
Soil Insects (Wireworm) Deseases
(Rootworm) ♦ Bean Root Rots (Pythium, fusar-
ium, Rhizoctonia, sclerotium)
♦ Anthracnose
♦ Angular leaf spot
♦ Bacterial blight
♦ Dumping off
♦ Fusarium wilt
Types of seed treatment:
Chemical treatment
This involves application of a chemical (fungicide/insecticide) to seed prior to planting 
to provide effective protection against many seed and soil-borne plant pathogens. 
The chemical treatment guards against the various seed rots and seedling blights that 
occur during storage or after planting. 
Some of the active ingredients in chemical seed dressing products include: Imida-
cloprid, Carbendazim, Carbofuran/carbosulfan, Thiram, Carboxin, Thiamethoxam, 
Metalaxyl-M and Difenoconazole
Examples of chemical seed dressing products for beans in Kenya include Apron Star 
42WS, SeedPlus, Murtano Super, Cruiser 350FS, Marshal 35DS, Treaty among others.
Always wear protective equipment and follow appropriate safety procedures when 
using chemical seed treatment products.
SEED TREATMENT TECHNOLOGIES FOR IMPROVED COMMON BEANS PRODUCTION 3
Biological treatment
Biological seed treatment consists of active ingredients that can include microbes 
such as fungi and bacteria, as well as plant extracts and algae extracts. The biological 
agents improve health of the root zone by competing with pathogens that may colonise 
seeds and newly emerged roots thus protecting the germinating seed and seedling 
from infection. The microbes stimulate rapid root development and nutrient uptake 
by the growing crop.
Some of the biological agents for seed dressing include Trichoderma spp., Rhizobium 
spp., Bacillus subtilis, Psedomonas flourescens, Azospirillum spp., Neem and sea weed 
extracts
Examples of biological seed dressing products in Kenya include: TriCoat, Mazao Flour-
ish, Trianum, Biofix and LEGUMEFiX.
Biological seed treatment products are environmentally friendly and easy to apply. 
These however required proper storage to keep viability of the biological agents.
How to do seed treatment
Seed treatment materials are usually applied to seed in various forms: dust; slurry (a 
mixture of wettable powder in water) and liquids. Slurry application is the most common 
method especially for smallholder farmers. Read and follow instruction for the specific 
application procedure for each seed treatment product.
Always wear protective equipment and follow appropriate safety procedures during 
seed treatment.
Procedure for chemical seed treatment
1
Plan to treat your seeds at the 
start of the rains when soil is 
moist and ready to plant.
Tibu mbegu zako mvua in-
apoanza na udongo ungali na 
maji tayari kwa upanzi
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2
Put on your gloves to protect 
yourself from the chemicals 
while mixing
Vaa glovu ili kujikinga na dawa 
unapochanganya
3
Measure the desired amount 
of seed using a tin (gorogoro), 
bucket or a weighing balance. 
You can treat both own saved 
seed or certified seed.
Pima kiwango cha mbegu 
unachohitaji kupanda kulin-
gana na kiwango cha dawa 
utakayotumia. Unaweza tibu 
mbegu za nyumbani au mbegu 
za gredi
4
Dissolve recommended amount 
of fungicide/insecticide per kg 
20ml seed in water inside a plastic 
bag or bucket to make a slurry. 
WATER
Weka dawa kwenye ndoo 
kisha ongeze maji kidogo. 
Changaya dawa na maji ili iwe 
chepechepe. 
SEED TREATMENT TECHNOLOGIES FOR IMPROVED COMMON BEANS PRODUCTION 5
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Put the seed in a bucket or a plastic 
bag. Do not use anything used for 
cooking or etching water.
Weka mbegu kwenye ndoo au 
karatais ya plastiki. Usitumie 
chombo cha kupikia au kuteka 
maji.
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Stir and mix well with a stick or 
hand protected by the glove. Alter-
natively seal the bucket and shake 
vigorously to coat seed uniformly 
with fungicide slurry.
Koroga na changanya vizuri 
ukitumia kijiti au mkono 
uliovaliwa glovu. Unaweza 
pia funika ndoo kisha tikisa ili 
kuchanganya dawa na mbegu. 
Tibu mbegu sawasawa
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Pour out the seed on a sack un-
der a shade for product to stick 
on seed. Keep the sack away 
from rain or direct sunlight
Mwaga mbegu juu ya gunia 
chini ya kivuli ili dawa ikaukie 
kwenye mbegu. Weka mbali na 
mvua au jua kali.
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8
Spread out the seed on a sack so 
that they are not on top of each 
other. Let them dry completely or 
until they have a powdery coating.
Tandaza mbegu vizuri zisiwe 
juu ya zingine. Wacha zikauke 
kabiisa hadi ziwe na funiko ya 
unga.
9
Plant the seeds exactly as normal 
into moist soil 
Panda mbegu kama kawaida 
kenye mchanga uliyo na un-
yevu.
SEED TREATMENT TECHNOLOGIES FOR IMPROVED COMMON BEANS PRODUCTION 7
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