Ramchandra Yadav, Niann-Tai Chang
Journal of Insect Science 14 (78), 1-9, (1 May 2014) https://doi.org/10.1673/031.014.78
KEYWORDS: fecundity, life table, thermal constant, threshold temperature
The effects of temperature on the melon thrips, Thrips palmi Karny (Thysanoptera: Thripidae), preimaginal development, survival, fecundity, longevity of females and males, and population growth were investigated at 16, 19, 22, 25, 28, and 31° C, 70–80% RH, and a photoperiod of 12:12 L:D. The results indicated that the duration of egg, larval, and pupal stages was significantly influenced by increased temperature. The egg-to-adult developmental period of T. palmi declined from 35.7 to 9.6 days as the temperature increased from 16 to 31° C. The developmental threshold temperature estimated for egg-to-adult was 11.25° C, with a thermal constant of 196.1 degree-days. The developmental threshold temperature was 13.91, 11.82, 9.36, and 10.45° C for adult pre-oviposition period, total pre-oviposition period, female longevity, and male longevity, respectively. The thermal constants for completing the adult pre-oviposition period, total preoviposition period, female longevity, and male longevity were 29.3, 227.3, 454.6, and 344.8 degree-days, respectively. Female longevity was found to be shortest at 31° C (18.7 days) and longest at 16° C (56.7 days), and male longevity was shortest at 31° C (15.5 days) and longest at 16° C (50.7 days). Fecundity was highest at 25° C (64.2 eggs/female) and lowest at 16° C (23.4 eggs/female). The population trend index of T. palmi was highest at 25° C (31.3) and lowest at 16° C (7.6). The optimal developmental temperature for T. palmi in eggplant, Solanum melongena L. (Solanales: Solanaceae), was determined to be 25° C.