The influence of resistance or susceptibility of certain maize genotypes on Chilo partellus colonization was studied. The aspects studied were: oviposition in relation to date of planting, plant age and certain morphological and biochemical characteristics. The pattern of oviposition was similar among the maize genotypes and among the different planting dates. However, the intensity of oviposition differed among the maize genotypes and also with plant age. Plants in the whorl stage of development were the most preferred for oviposition. On the whorl-stage plants, ca 92% of all the eggs were deposited on the lower leaves (1–4 from the ground). As the lower leaves senesced with plant age, the upper leaves were selected for oviposition. On all leaves, the lower surfaces were more preferred. The plant characters that appeared to influence oviposition included plant exudates (as the moth diet) and leaf surface trichomes. The quality of exudates from the different genotypes appeared to influence moth fecundity and longevity, while the trichomes appeared to influence the selection of oviposition sites. The possibility of interactions between these factors and oviposition is discussed.