Developmental threshold temperature and effective accumulated temperature of Lithocolletis ringoniella.

The developmental durations of different stages of Lithocolletis ringoniella Matsumura were investigated at room temperatures.The results showed that the threshold temperatures of adult pre-oviposition,egg,larval,pupal stages and whole generation were 7.5,5.2,10.4,11.3 and 7.1℃ with effective accumulated temperature of 40.6,59.7,102.2,15.4 and 203.1 degree-day respectively. It is predicated that there were 4～6 generations per year occurred in Shandong Province.The adults of 1st and 2nd generations emerged in late May and late June in Taian, Shandong Province.