POPULATION-DYNAMICS AND PARASITISM OF CONIESTA (= HAIMBACHIA) IGNEFUSALIS, SESAMIA-CALAMISTIS, AND HELIOCHEILUS-ALBIPUNCTELLA IN MILLET MONOCULTURE

Studies were conducted in Niger in 1986 and 1987 on the population dyn amics and parasitism of the millet stem borer, Coniesta (=Haimbachia) ignefusalis (Hampson) (Lepidoptera:Pyralidae), Sesamia calamistis Hamp son, and the millet head caterpillar, Heliocheilus albipunctella de Jo annis (Lepidoptera:Noctuidae). Planting dates were assessed for effect s on population densities of C. ignefusalis and H. albipunctella. Popu lation densities of C. ignefusalis were not reduced by adjusting mille t planting dates, but were affected by millet growth stage. Platytelen omus sp. (Hymenoptera: Scelionidae) was the most common parasite of C. ignefusalis on millet. Parasitism of C. ignefusalis larvae and pupae was rare. Sesamia calamistis was a minor pest of millet in Niger, and was rarely parasitized. Population densities of H. albipunctella were reduced by delaying millet planting dates. Bracon hebetor (Hymenoptera : Braconidae) was the most common parasite of H. albipunctella.