S2 line and S2 test-cross recurrent selection procedures were initiated to improve the resistance of a maize (Zea mays L.) population to the spotted stemborer, Chilo partellus (Swinhoe) (Lepidoptera: Pyralidae). Thirty-five selections developed from the population were evaluated for resistance to the stemborer in western Kenya. Resistance was rated according to leaf feeding (LF), stem tunnelling (ST) and deadheart formation (DH) following artificial infestation with first-instar C. partellus. Larval establishment and growth were also assessed. The reduction in foliar damage ratings, percentage stem length tunnelled, and percentage of plants showing deadheart after one cycle of recurrent selection were 4.38 %, 74.80 % and 13.92 %, respectively. A very low larval establishment on all the selections was attributed to their resistance to C. partellus attack. Results from this study indicated low levels of larval growth and development. It is concluded that antibiosis was the type of resistance mechanism against C. partellus in the maize populations investigated and that more cycles of selection are required to significantly shift the gene frequencies for resistance.

The main thrust of the article is to present the historical development of the idea of Integrated Pest Management (IPM) from the heyday of “pestophobia” (the insistence of elimination of any vestige of insect interference with the cosmetic appearance of our crops), which leads to the misuse and abuse of insecticides, to the era of employing IPM concepts, which leads to pest interventions which are necessarily knowledge-intensive. Illustrations are given using ICIPE's research experience in developing an IPM approach to the control of Chilo through adaptation of relevant intercropping patterns, plant resistant cultivars and biological control agents. In this task, the IPM specialist needs to have three assets to be successful in the tropics: he needs to be a first-class natural historian; he requires to build his new knowledge on the traditional knowledge of the rural farmer, and to rationalize it scientifically, and he needs to be able to manipulate new innovations—both technical and social.