Effect of temperature on immatures of Stiretrus decastigmus (Hemiptera: Pentatomidae)

Efeito da temperatura sobre imaturos de Stiretrus decastigmus (Hemiptera: Pentatomidae)

S. Poncio S. T. B. Dequech A. Bolzan C. Güths M. P. Walker V. S. Sturza D. E. Nava About the authors

Abstract

Stiretrus decastigmus (Herrich-Schaeffer) (Hemiptera: Pentatomidae) is an important predator of the insect pest Microtheca ochroloma Stal (Coleoptera: Chrysomelidae). The present study investigated the pre-imaginal development of S. decastigmus at different temperatures. The temperatures were: 20, 25, and 30 °C, with a relative humidity of 70 ± 10% and a photofase of 12 h, and the nymphs were fed larvae of M. ochroloma. We evaluated the duration and viability of the egg and nymphal stages, the duration of each instar, and the predation potential. The incubation time decreased with increasing temperature, and the viability was highest at 25 °C. The duration of the nymphal stage was inversely proportional to the temperature, ranging from 18 days at 30 °C to 40.6 days at 20 °C. The highest S. decastigmus predation rates were found at 20 °C (90.4 larvae) and 30 °C (72.5 larvae). S. decastigmus showed the highest viability and lowest consumption of larvae of M. ochroloma at 25 °C.

Keywords:
Asopinae; Chrysomelidae; biological control; predator

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