Temperature-dependent development of Lista haraldusalis (Walker) (Lepidoptera: Pyralidae) on Platycarya strobilacea

Abstract

The effect of constant temperatures on development and survival of Lista haraldusalis (Walker) (Lepidoptera: Pyralidae), a newly reported insect species used to produce insect tea in Guizhou province (China), was studied in laboratory conditions at seven temperatures (19°C, 22°C, 25°C, 28°C, 31°C, 34°C, and 37°C) on Platycarya strobilacea. Increasing the temperature from 19°C to 31°C led to a significant decrease in the developmental time from egg to adult emergence, and then the total developmental time increased at 34°C. Egg incubation was the stage where L. haraldusalis experienced the highest mortality at all temperatures. The survival of L. haraldusalis was significantly higher at 25°C and 28°C, whereas none of the eggs hatched at 37°C. Common and Ikemoto linear models were used to describe the relationship between the temperature and the developmental rate for each immature stage of L. haraldusalis. The estimated values of the lower temperature threshold and thermal constant of the total immature stages using Common and Ikemoto linear models were 11.34°C and 11.20°C, and 939.85 and 950.41 degree-days, respectively. Seven nonlinear models were used to fit the experimental data to estimate the developmental rate of L. haraldusalis. Based on the biological significance for model evaluation, Ikemoto linear, Logan-6, and SSI were the best models that fitted each immature stage of L. haraldusalis and they were used to estimate the temperature thresholds. These thermal requirements and temperature thresholds are crucial for facilitating the development of factory-based mass rearing of L. haraldusalis.