Ecological management of cereal stem borers in Ethiopia. Integrated Approaches to Higher Maize Productivity in the New Millennium.

Abstract

Three lepidopterous stem borers were reported on maize in Ethiopia. Although complete crop loss is evident in some areas, the average yield loss of maize caused by cereal stem borers in Ethiopia can be estimated between 20 and 50%. A resource-poorfarmers produce over 87% of aize, inexpensive, ecologically sound and effective cereal stem borer control methods are indispensable. To this end, surveys and field experiments were conducted in 1999 and 2000. Surveys were conducted in major maize growingareas of eastern, western, southern and northern thiopia. In the surveys, four stel1 borers, 20 species of parasitoids, 14 species of predators and seven entomopathogens were investigated. These natural enemies gave about 18% re<1:uction of cereal stem borers. Of these natural enemies Cotesia flavipes Cameron (Hymenoptera raconidae) alone gave 13% reduction. Intercropping of maize with beans significantly (P