Larvae of P. xylostella were originally collected from a cabbage
field in Yangling, Shaanxi, China (3428.2040
N, 10807.4480
E) in
March, 2010. Larvae were maintained on cabbage at 25 0.5 C
(day), 22 0.5 C (night), 60 5% RH, and a photoperiod of 16:8
(L:D) h. To mitigate potential bottleneck effects in the laboratory
population, P. xylostella was collected fromthe field and introduced
into the colony monthly.