Research On The Application Techniques Of Habrobracon Hebetor (Say) For Controlling Helicoverpa Armigera And Ostrinia Furnacalis

Habrobracon hebetor (Say), one of the most important parasitoid wasps, has been argumentatively released to control the damage of cotton bollworm, Helicoverpa armigera (HUbner), in many years in Uzbekistan of the middle Asia, and provided a very successful example for protection of cotton by biological control. The application methods and control efficiencies of using H. hebetor against cotton bollworm and corn borer, Ostrinia furnacalis in Xinjiang of the northern China were studied during the summers of 2005 and 2006. The techniques of mass rearing, storage, rejuvenation and field application of H. hebetor were summarized as follows:1. The late instar larvae of greater wax moth, Galleria mellonella L., were used as mediate host in wasp mass rearing. These larvae could be stored for 45-50 days at 10±1℃, and provide enough hosts for H. hebetor.2. The optimum condition for mass rearing of H. hebetor were 28±1℃, RH 75±5%, without light(L: D＝0 : 4).3. Inoculative wasps could be rejuvenated with larvae of Ostriniafurnacalis Guenee and Corcyra cephalonica (Stainton). The parasitoid ratio and the density of pupation in each larva of O. furnacalis and C. cephalonica were significantly higher than that on the larvae of H. armigera and Grapholitha molesta Busck.4. Inoculative wasps could be stored for 30 days at low temperature (7～10℃), and periodical rearing bee honeydew can decrease the mortality of H. hebetor.5. For controlling O. furnacalis in maize field, H. hebetor needs to be released three times during the peak larval stage of O. furnacalis and the control effect can reach to 75%. The release densities (wasps/666.7m²) of H. hebetor was 300～500 at each time with interval of 7days.6. For controlling H. armigera in cotton field, H. hebetor needs to be released two times during the peak larval stage in each generation of H. armigera and the control effect can reach to 65%. The release densities (wasps/666.7m²) of H. hebetor was 700-1000 at each time with interval of 7days.7. The H. hebetor just stings the larvae that are more than the 3^rd instar.By this behavior, only large larvae (4^th～5^th instar larvae of O. furnacalis, 5^th～6^th instar larvae of H. armigera) are parasitized by H. hebetor.