A TECHNIQUE FOR MEASURING INTRASPECIFIC VARIATION IN OVIPOSITION PREFERENCE IN HELICOVERPA-ARMIGERA (HUBNER) (LEPIDOPTERA, NOCTUIDAE)

Intra-population variation in oviposition preference of Helicoverpa ar migera was examined using two testing techniques; oviposition choice e xperiments with free flying females in cages of two sizes, and a novel technique in which tethered insects were brought in contact with the test leaf discs by the experimenter. Though individual females differe d in oviposition preference, most ranked maize, sorghum and tobacco hi ghest, followed by cotton. The least preferred plants were cowpea and lucerne. However, a few of the females had quite different preferences both from the majority and between each other. Individual females con sistently ranked plants in the same order within a test across days an d across tests, regardless of the order in which testing procedures we re used. The use of the tethered insect technique in assessing host pr eference of H. armigera is discussed.