Vol. 8, Special Issue 9, Part A (2024)

Abstract: Maize fall army worm is an invasive insect which entered India in 2018 through Karnataka state. It’s damage starts from seedling stage itself which when neglected results in complete crop failure. As it damages the maize crop by remaining hidden in leaf whorls and cobs, it’s management turns to be difficult with even newer group of insecticides. Search for promising botanicals that not only cause larval mortality, but also with antifeedant and growth inhibitory effects fits well in to the IPM of this insect. In this direction, Annona squamosa (seed extract SE), Zingiber officinale (rhizome extract - RE), leaf extract (LE) of Lantana camara, Agave americana and Eclipta prostata were screened. Cumulative mortality of fall army worm larvae was 100% in Agave americana 5% LE. But, mortality caused by this treatment in first two days was very minimal. The next best was A. squamosa 5% SE with 74.0% cumulative mortality and was on par with Azardirachtin 1% (73.4%). However, mortality effect of A. squamosa 5% SE started at 24 hours after treatment (HAT) itself. At 48 HAT also, A. squamosa 5% SE recorded higher FAW larval mortality. Highest antifeedant index was recorded with A. squamosa 5% SE (84.71) followed by Azardirachtin 1% (74.31). In A. americana 5% and standard check, Azadirachtin 1%, all the larvae were dead after four days. In the rest of the treatments, minimum weight gain by FAW larvae was observed in A. squamosa 5% SE. Larval duration was prolonged in A. squamosa 5% SE (25.33 days) and Z. officinale 5% RE (23.17 days) and in untreated control, 15.17 days was the FAW larval period. Pupal weight was minimum (150 mg) in A. squamosa 5% SE and Z. officinale 5% RE (159.88 mg) while in untreated control, it was 237.29 mg. In these treatments, pupal duration, pupation per cent and adult emergence per cent were also less.