# Lethal and Sublethal Effects of Selected Insecticides on the Eggs of the Predatory Bug Orius niger

## TL;DR

This study tests how six insecticides affect the eggs of Orius niger, a beneficial predator, and identifies which are safest for use in integrated pest management.

## Contribution

The study provides empirical data on insecticide compatibility with O. niger eggs, aiding in the selection of safer insecticides for biological control integration.

## Key findings

- Acrinactrin and spinosad significantly reduced egg survival and development of Orius niger.
- Pyriproxyfen and spiromesifen showed the least harmful effects and highest compatibility with O. niger.
- Chlorantraniliprole and spinosad negatively impacted reproductive parameters of the predator.

## Abstract

Orius niger is an important beneficial predator used to control insect pests in agricultural systems. However, chemical insecticides applied against pests may also harm this predator. In this study, we evaluated the effects of six commonly used insecticides on the egg stage of O. niger. We found that acrinactrin and spinosad caused strong negative effects on egg survival and later development, making them unsuitable for use where this predator is present. In contrast, pyriproxyfen, flupyradifurone, chlorantraniliprole and spiromesifen showed limited harmful effects and were more compatible with O. niger. These results provide useful information for selecting insecticides that can be safely integrated with biological control in integrated pest management programs.

The compatibility of insecticides with biological control agents is a critical component of integrated pest management (IPM). In this study, the lethal and sublethal effects of acrinactrin, chlorantraniliprole, flupyradifurone, pyriproxyfen, spinosad, and spiromesifen on the egg stage of Orius niger (Wollf) (Hemiptera: Anthocoridae) were evaluated under laboratory conditions. Egg hatchability, immature survival, reproductive performance, and population parameters were analyzed using the age-stage, two-sex life table. Egg hatchability was lowest in the acrinactrin treatment (51%) and highest in the pyriproxyfen treatment (93%). Nymphal survival varied from 0% to 80%, with acrinactrin causing complete mortality and a significant reduction in spinosad, while the highest nymphal survival and population growth was recorded in spiromesifen treatment. The intrinsic rate of increase (r, day−1) was 0.00, 0.05, 0.05, 0.08, 0.004, and 0.06 for acrinactrin, chlorantraniliprole, flupyradifurone, pyriproxyfen, spinosad, and spiromesifen, respectively, while fecundity (F, eggs female−1) values were 0, 15.20, 15.83, 42.32, 10.37, and 21.85, respectively. According to the International Organization for Biological Control (IOBC) classification, acrinactrin was harmful, spinosad moderately harmful, and the remaining insecticides slightly harmful to O. niger eggs. Pyriproxyfen and spiromesifen were the most compatible with IPM programs. Caution is warranted for chlorantraniliprole due to its effects on reproductive parameters, whereas spinosad and acrinactrin should be avoided on O. niger eggs.