Effect of temperature and humidity on development, reproduction, and predation rate of Amblyseius swirskii (Phytoseiidae) fed on Phyllocoptruta oleivora (Eriophyidae) and Eutetranychus orientalis (Tetranychidae)

Abstract

ABSTRACT The developmental, survival, predation rates, and reproduction of Amblyseius swirskii (Phytoseiidae), as affected by feeding on the motile stages of Phyllocoptruta oleivora (Eriophyidae) and nymphs of Eutetranychus orientalis (Tetranychidae), were studied in the laboratory at six constant temperatures and relative humidities: 9°C and 70% RH; 16°C and 65% RH; 23°C and 60% RH; 30°C and 55% RH, 37°C and 50% RH and 40°C and 45% RH. The maximum daily consumption rate was recorded at 30°C and occurred during the oviposition period, when the females consumed an average of 169.40 specimens of P. oleivora and 24.58 of E. orientalis. The maximum reproduction rate (4.20, and 3.84 eggs/♀/day, on P. oleivora and E. orientalis, respectively) was recorded at 30°C and 50% RH, while the minimum one (1.20 and 0.86 eggs/♀/day, on P. oleivora and E. orientalis, respectively) was observed at 16°C and 65% RH. It is demonstrated in the life-table parameters that when the predatory mite A. swirskii is fed on P. oleivora, the highest reproduction rates (rm = 0.144, 0.195, 0.280, and 0.181 females/female/day) are obtained, while feeding on E. orientalis gave the lowest reproduction rates (rm = 0.121, 0.172, 0.204, and 0.141) at 16°C and 65% RH, 23°C and 60% RH, 30°C and 55% RH, and 37°C and 50% RH, respectively. The results suggest that A. swirskii is a promising control agent for P. oleivora and E. orientalis on orange trees.