The inheritance of resistance in grain sorghum to the spotted stemborer, Chilo partellus (Swinhoe) (Lepidoptera: Pyralidae) was studied in F3 plants derived from crosses between nine locally adapted inbred lines and two sources of resistance. Antibiosis resistance was measured as the relative growth rate of larvae in the whorls of 6-week-old plants. Most F3 plants were either as resistant as, or more resistant than, the resistant parent. This indicated dominance of resistance over susceptibility and the occurrence of transgressive segregation. The segregation pattern in the F3 generation suggested the presence of at least four dominant genes. Two families homozygous for these genes were identified.
