Theory question 106
Crop Pests(a) State three effects of maize weevil on maize grains.
(b) Explain briefly five general control measures of insect pests of grains in storage.
(c) Name the vector for each of the following crop diseases: (i) groundnut rosette. (ii) maize streak. (iii) cassava mosaic.
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(a) Any three: bore holes in grains; reduce weight and food value; lower viability/germination; contaminate grains with droppings, encourage moulds and heating; reduce market value
(b) Any five: dry grains well before storage; clean and disinfect stores before use; fumigation (e.g. phostoxin); dust with storage insecticides (e.g. Actellic); airtight storage containers; store on raised platforms/use pallets; sort out infested grain; use resistant varieties; traditional methods such as ash or pepper
(c)(i) Aphids (Aphis craccivora); (ii) leafhoppers (Cicadulina spp.); (iii) whiteflies (Bemisia tabaci)
Name the correct insect vector for each disease.