Thermal effects on the development of Naranga aenescens Moore (Lepidoptera: Noctuidae)

Abstract

Naranga aenescens Moore is an important insect pest found in rice paddy field. We investigated the development periods of N. aenescens egg, larva, pupa, and total immature insects at eight constant temperatures: 15.0°C, 17.5°C, 20.0°C, 22.5°C, 25.0°C, 27.5°C, 30.0°C, and 32.5°C. N. aenescens developed successfully from the egg stage to the adult stage at all the tested temperatures except 15.0°C. The developmental time of each life stage was significantly influenced by temperatures. The developmental rate of N. aenescens increased as the temperature increased from 15.0°C to 30.0°C but declined at 32.5°C, except in the pupa stage. The lower developmental threshold (LDT) and the thermal constant (K) was estimated using linear regression. The higher temperature threshold and the lower temperature threshold were calculated using two nonlinear functions. LDT and K from egg to adult emergence were 12.01°C and 330.84 degree days, respectively. The temperature range of N. aenescens from the lower developmental threshold to the higher developmental threshold using a performance model (24.03) was wider than that determined using the Sharpe–Schoolfield–Ikemoto model (19.77). Developmental completion of N. aenescens was described using a two-parameter Weibull distribution model. Adult emergence frequency of N. aenescens over a full range of constant temperatures was simulated using developmental rate functions and the Weibull function. Biological characteristics of N. aenescens populations from different geographic areas were discussed.