Bionomics of Sonsaucoccus sinensis in Jiuzhaigou

Sonsaucoccus sinensis(Chen)mainly attacks Pinus tabulaeformis and other Pinus spp.in Jiuzhaigou.It has one generation a year and overwinters in needles as the nymph in the 2nd instar.The male nymph matures and pupates in the last ten days of March.The adult emerges and mates in the first ten days of May and lays eggs in the first ten days of June.The nymph hatches in the last ten days of June and begins to overwinter in in the last ten days of October.It annual dynamic trend includes 3 stages,namely damage of overwintering generation,damage of newly hatched nymph and natural decline in the population.The occurrence and damage are closely related to temperature,humidity,altitude,aspect of slope and so on.