Abstract: In order to comprehensively evaluate the impacts of cold storage on Trichogramma reared  on Corcyra cephalonica eggs, the effects of cold storage on pupal survival rates, adult emergence rates and adult deformity rates of Trichogramma chilonis were investigated through applying storage temperature (3℃ and 10℃), day-age (age from 1 to 10 days after parasitization of wasp on host egg, respectively) and period (1, 2, 3 and 4 weeks) as the experimental factors and taking C. cephalonica eggs as the host. The results indicated that those three factors substantially influenced the pupal survival rates, adult emergence rates and adult deformity rates separately or interactively (P＜0.05). Among all storage temperatures tested, T. chilonis was most susceptive to 3℃, its pupal survival rate for the age of 1-3-day-old and adult emergence rate for all ages decreased notably at this temperature (P＜0.05), and therefore 3℃ was considered to be unfavorable for long-term storage. At 10℃, pupal survival rates for all ages and adult emergence rates for the age of 1-3-day-old were not affected by the storage period, and the adult emergence rate was still over 74% after cold storage of 4 weeks, thus 10℃ was considered to be more favorable for storage than 3℃. The favorable age for cold storage varied with different storage temperatures. At 10℃, which was favorable for cold storage, the most favorable age was for 3dayold while there was no distinct difference from the control groups in pupal survival rates (74.09%-77.59%) and adult emergence rates (74.26%-90.37%) in different periods, but they were notably higher at this age than those in other ages. After the cold storage under 10℃ for 1-3 weeks, the adult deformity rates were within 27%. The results suggest that the favorable age for cold storage of T. chilonis reared on C. cephalonica eggs varies with different cold storage temperatures.

Key words: Trichogramma chilonis, Corcyra cephalonica egg, cold storage, temperature, age, storage period, adult emergence rate, adult deformity rate