Abstract Background : Rice stem borers constitute a serious threat to rice production in Burkina Faso. Trials were conducted in 2022 and 2023 at Bama and Karfiguéla, western Burkina Faso. The study aimed at assessing the biodiversity associated with rice Lepidoptera stem borers when using biological insecticides for the control of these insect pests. Methods : A randomized completely block design with six treatments and four replications was used. Treatments included two botanical insecticides ( Azadirachta indica , Jatropha curcas ), two entomopathogens ( Bacillus thuringiensis , Trichoderma sp.) followed by an untreated control and, a positive control (deltamethrin). Six insecticide applications per treatment were carried out at a frequency of 14 days each, starting on the 15th day after transplanting (DAT). Oil extracts from A. indica , J. curcas , and B. thuringiensis , as well as deltamethrin, were applied to the rice plants, while Trichoderma sp. was applied directly to the soil. Arthropod specimens were caught weekly, from the 14th to the 84 DAT using sweep net and pitfall traps. Results : Results revealed that the highest arthropod catches were recorded during the 2022 wet season. Regardless of study site and season, predators were grouped into seven orders, while parasitoids were observed in two orders in the 2022 wet season and a single order in the 2023 dry season. Parasitoids were mainly Hymenoptera, while predators were dominated by spiders. The highest proportions were recorded in plots treated with A. indica oil. The highest diversity and distribution of natural enemy species was reached out with A. indica . Conclusions : These results show that the use of A. indica oil is compatible with the conservation of natural enemies associated with Lepidoptera rice stem borers.
Latévi et al. (Fri,) studied this question.