The distribution and importance of stem-borer species of sorghum in Kenya, viz. Chilo partellus Swinhoe, C. orichalcociliellus Strand, Busseola fusca Fuller, Eldana saccharina Walker and Sesamia calamistis Hampson were studied and discussed. The incidence and period of activity of the stem-borer complex on sorghum indicated that C. partellus, which is a major pest, infested the crop early, while E. saccharina and S. calamistis infested late and persisted in the crop till it was harvested. Preliminary studies on the carryover of stem-borer showed that the larvae of C. partellus and S. calamistis were able to enter diapause in dry sorghum stalks for several months at the end of long and short rain seasons. Some new alternative host plants and parasites and predators affecting different life stages of stem-borers were identified. Preliminary screening of several sorghum lines was carried out for identification and confirmation of resistance to C. partellus and B. fusca, and some sources of resistance were reported.
