Preliminary studies on biological characteristic of Aphytis huidonggensis Huang.

Aphytis huidonggensis Huang is a local parasitoid which parasitizes important pest of forest,Hemiberlesia pitysophila Takagi.The morphological characteristics were studied to provide some suggestions for the artificial protection and application in the future.The results showed that the most morphological characteristics of adults were similar to it's sibiling species,but different from them in antennae style and relative length of ovipositor.Under the condition of(25±1)℃ and 70%RH,A.huidonggensis completes its preimage stage inside the host in less than 23.6 d after ovipositing,with egg stage(2.3±0.4)d,larvae stage(12.8±1.5)d,pupae stage(8.5±0.8)d.The longevity of parasitoid was about 3.1～20.6 d under different temperatures from 15℃ to 35℃,and the female survives longer than the male.The threshold temperature of development for the generation was 9.227℃,and the effective accumulative temperature for total life history was 301day degrees.The parasitoids could feed with 20% honey water after eclosion between 12:00～16:00 at day light,and had the taxis,parthenogenesis habits.In forest,the summit of population occurred between April and June with sex ratio 7.15∶1