Comparative effects of biopesticides on fall armyworm management and larval parasitism rates in northern Ghana

Abstract The outbreak of the fall armyworm, Spodoptera frugiperda, in Africa has led to several recommendations insecticides, including biopesticides. However, effects these products on environment, especially parasitoids have not been assessed under field conditions. Here, we investigated effect commonly used biopesticides S. frugiperda management and larval northern Ghana. experiments were conducted both on-station Wa Nyankpala on-farm during 2020 rainy season. Active ingredients tested included neem oil (3% Azadirachtin), maltodextrin (282 g/l), 55% Bacillus thuringiensis ( Bt ) combined with 45% Monosultap, a Pieris rapae granulosis virus 5% . A chemical insecticide based emamectin benzoate acetamiprid was as positive control while non-treated maize plots considered untreated control. two most abundant Coccygidium luteum Chelonus bifoveolatus , they C. Meteorus sp. Total parasitism rates 18.7% 17.6% Nyankpala, respectively, 8.8% on-farm. Parasitoid species diversity evenness indexes did vary among treatments, but significantly lower product Nyankpala. Untreated showed highest density plant damage, cob generated lowest yields. other treatments hardly any difference damage yields, suggesting that should be preferred over pesticides for