Mating behavior of the predator Podisus nigrispinus (Heteroptera: Pentatomidae) under exposure to neem.

Sharrine Omari Domingues de Oliveira1*, Wagner Faria Barbosa1, Karina Soledad Vilca Malqui1, and Raul Narciso Carvalho Guedes1

The preservation of natural enemies is one of the basic foundations for integrated pest management. Botanical insecticides have shown low impact on beneficial arthropods in relation to survival. Insecticides studies usually focus on the direct physiological effects of insecticides, whereas relatively little attention is placed on the behavioral response to exposure. A study was conducted to evaluate the effect of the botanical insecticide neem (Azadirachta indica A. Juss.; Meliaceae) on the mating behavior of the predatory stinkbug Podisus nigrispinus (Heteroptera: Pentatomidae). Unmated 5 to 7 d-old adults, separate by sex, were exposed to azadirachtin per contact on the treated surface. The treatments were composed for: untreated male and female; untreated male and treated female; treated male and untreated female; and treated male and female. Azadirachtin affected the duration of first mating (Wilcoxon test, χ2 = 13.38, df = 3, p = 0.004), which resulted in a higher effective average time of mating (EATM50) for treatment whose only female was treated with azadirachtin. This finding points to a sublethal effect of azadirachtin on mating behavior of P. nigrispinus that may compromise its reproduction.

Keywords: Azadirachtin, Azadirachta indica, biological insecticide, natural enemy.
1Universidade Federal de Viçosa, Apartamento de Entomologia, Viçosa, Minas Gerais, Brasil. CEP: 36570-000. *Corresponding author (sharrineoliveira@hotmail.com).