Inventory of the main local parasitoids of Helicoverpa armigera (Hübner, 1808) and their potential for biological regulation in the Niayes area of Senegal

Abstract

Knowledge of parasitoids is essential for biological control in order to contribute to the sustainable management of pests. The objective of our study was to inventory the main parasitoids of Helicoverpa armigera according to the different crops infested in the fields and to evaluate their potential for biological regulation on this insect. Four different localities in the Niayes area are being surveyed (Malika Plage, Malika Montagne, Notto Guy Diama, Thiès) between 2022 and 2023. Four species of parasitoids are identified: Meteorus sp. (5.41%), Ephedrus sp. (4.05%), Cotesia sp (1.35%), Phryxe sp. (4.05%). With a total parasitism rate of 18.92%, based on 125 larvae. Malika (S=5) has the greatest diversity of parasitoid species in the southern Niayes zone. The first larval stages (L1, L2, L3) are the most parasitized, with L3 (53.85%, S = 4) the most successful stage. Depending on the host plant, the tomato harbors more parasitoid species of H. armigera than other crops (cabbage, green beans). The results suggest that sustainable biological control of H. armigera could be implemented by strengthening parasitoid populations, particularly Meteorus sp, Ephedrus sp. and Phryxe sp.