Fig. 1.

Photoperiodic response curves for nymphal diapause induction in L. striatellus for three populations at 20°C (A) and 27°C (B). The CPs were ∼12 hr 30 min (CP1) at 20°C and 11 hr (CP3) at 27°C in the JY, and 13 hr (CP2) at 20°C and 11 hr 20 min (CP4) at 27°C in the CC. Different uppercase letters indicate significant differences in the diapause incidences among the three populations at the same photoperiod and temperature. Diapause incidences were arcsin square-root transformed prior to analysis. The sample size for each treatment varied from 174 to 315. HN, Hanoi population; JY, Jiangyan population; CC, Changchun population.