Starvation Tolerance of the Predators Anthocoris minki and Orius laevigatus (Hemiptera: Anthocoridae) and Its Implications for Biological Control

Predatory bugs Anthocoris minki Dohrn and Orius laevigatus Fieber (Hemiptera: Anthocoridae) are important biological control agents. Within the scope of biological control, knowledge of the starvation tolerance of beneficial insects is crucial for their release at the appropriate biological stage. In this study, experiments were conducted under laboratory conditions at 25±1 °C, 65±5% relative humidity, and a 16:8 h light:dark photoperiod. The predatory bugs were reared on eggs of Ephestia kuehniella Zeller (Lepidoptera: Pyralidae). According to the results, the starvation tolerance of A. minki nymphs increased with nymphal development. The starvation tolerance of the nymphal stages of A. minki was determined as 1.40, 2.19, 3.73, 4.08, and 4.52 days for the first to fifth instars, respectively. Females of A. minki survived longer under starvation (3.99 days) than males (3.48 days). The starvation tolerance of O. laevigatus nymphs was 2.44, 2.38, 3.55, 4.40, and 4.28 days for the first to fifth instars, respectively. These data indicate that the fourth nymphal stage of O. laevigatus exhibited the highest starvation tolerance, followed by the fifth and third instars. Female adults of O. laevigatus survived longer than males, with durations of 3.57 and 3.15 days, respectively. Consequently, for release programs, it is recommended that A. minki be released at the fifth nymphal stage, whereas O. laevigatus should be released at the fourth or fifth nymphal stage. Since starvation tolerance is an important criterion for beneficial insects in biological control programs, the findings of this study have practical relevance.