Effect of Photoperiod and Temperature on the Life Table Parameters of Onion Thrips (Thrips tabaci) Lineages

Abstract This study investigated the effect of photoperiod and temperature on the bionomics of the three Thrips tabaci lineages (L1 and L2 – leek-associated, and T – tobacco-associated). The experiment was performed in the laboratory under the following conditions: 23 °C 16L/8D and 8L/16D, and 15 °C under 8L/16D. Reproductive diapause was detected in the T lineage at 23 °C and 8L/16D, but not in the L1 and L2 lineages, while all three lineages diapaused at 15 °C and 8L/16D. Adult longevity of L1, L2, and T lineages were 29.51, 25.69, and 29.76, respectively, at 23 °C under 16L/8D; 30.9, 28.52, and 38.06, respectively, at 23 °C under 8L/16D; and 48.9, 34.22, and 76.89 days, respectively, at 15 °C. Mean fecundity of L1, L2, and T lineages were 89.30, 80.31, 86.76, respectively, at 23 °C under 16L/8D; 40.14, 46.94, and 39.34, respectively, at 23 °C under 8L/16D; and 7.0, 13.85, and 17.87, respectively, at 15 °C. The difference in responses to photoperiod and temperature could be a factor to cause a sympatric population variation of the different T. tabaci lineages under the same environmental condition.