Published online by Cambridge University Press: 19 September 2011
Two field experiments were conducted over two seasons to assess the effect of resistance levels of sorghum varieties on follow-up generations of Chilo partellus. Sorghum varieties, released by the Southern African Development Community/International Crops Research Institute for the Semi-Arid Tropics (SADC/ICRISAT) through the Sorghum and Millet Improvement Program (SMIP) in the southern African region, were evaluated for their ability to provide for larvae to complete development in stalks and emerge as moths. Plants were naturally infested by C. partellus. The number of moth exit holes per stem was used to calculate survival of larvae to the adult stage. A moth production index was calculated to estimate the role of each sorghum variety in area-wide suppression of stemborer abundance. Between 97,500 and 213,125 moths per hectare emerged from the different sorghum varieties in trial 1 while between 0 and 77,500 emerged per hectare in trail 2. Resistant sorghum varieties may help suppress pest population build-up and be of considerable value in development of IPM systems for resource-poor farmers.