Abstract: 【Aim】 The rearing host affects biological characteristics of Trichogramma. In order to know the differences between Trichogramma japonicum Ashmead reared on Corcyra cephalonica (Stainton) eggs and reared on Chilo suppressalis (Walker) eggs in the control effect on Ch. suppressalis, and also the possibility of using Co. corcyra eggs as the alternative host of T. japonicum in the field, we observed the host preference and parasitization behavior of T. japonicum emerged from different rearing hosts, and investigated the effects of rearing host on the parasitization capacity of T. japonicum, so as to provide basic information for the control of rice borer with Trichogramma. 【Methods】 The host preference of T. japonicam reared on Co. cephalonica eggs (TjCc) and Ch. suppressalis eggs (TjCs), respectively, were observed in choice tests in the laboratory. The parasitization behavior and capacity of TjCc and TjCs on eggs of Ch. suppressalisand Co. cephalonica, respectively, were investigated. 【Results】 TjCs preferred Ch. suppressalis eggs to Co.cephalonica eggs, while TjCc did not show preferences. The host searching time was not significantly affected by either rearing host or host for parasitization, and both the outside host examination time and ovipostion time were not significantly affected by rearing host. However, the outside host examination time of both TjCc and TjCs on Co. cephalonica eggs was significantly longer than that on Ch. suppressalis eggs. The parasitism rate (36.95%) on Ch. suppressalis eggs and the emergence rate (45.68%) of TjCs were lower, respectively, than those in other three combinations (TjCc-Cc, TjCc-Cs and TjCs-Cc) among which no significant differences were found. The longevity of emerged wasps was not significantly different among the four treatments. 【Conclusion】 The rearing host affects the host preference and parasitization capacity of T. japonicum, but does not affect the host searching ability and parasitization behavior of the wasp.

Key words: Trichogramma japonicum, parasitization behavior, host preference, Cocyra cephalonica, Chilo suppressalis, parasitism rate, emergence rate, longevity