| In this paper, spinosad sublethal doses impact of biology and behavior of Fopius arisanus (Sonan), and feeding a large number of pupae stored at low temperature was studied, discussed the changing temperature, changing temperature and wet temperature of the bee.1)The effect of biological characters of F. arisanus of sublethal concentrations of spinosadTested cohorts of the parasitoid F. arisanus were reared on a strain of the host, Bactrocera doralis (Hendel), which was sensitive to spinosad. The toxicity tests showed that the LC50 of spinosad for female and male adults of F. arisanus were 0.0908mg/mL and 0.0274 mg / mL respectively, while the LD50 were 1.0041 mg and 0.8043 mg respectively. The effects of diluted 1000, 2000 and 3000 times of spinosad as sublethal concentrations on F. arisanus were observed. The results revealed that all sublethal concentrations could significantly shorten the longevity of F. arisanus, reduce the total fecundity of females and the average fecundity when compared to the control. The parasitism rate and the emergence rate of adults of offspring also decreased with the sublethal concentration increasing of spinosad, but the sex ratio of offspring had no notable difference compared to the control. The simulated equation of the effect of F. arisanus on the eggs of B. doralis corresponded to HollingⅡtype model, but the instantaneous attack rate reduced, the handling time prolonged and the searching efficiency declined with the increasing of sublethal concentrations of spinosad. These results suggested that the sublethal concentrations of spinosad would affect significantly the bio-control effect of F. arisanus on B. doralis.2) The effect of response to pheromone of F. arisanus of sublethal concentrations of spinosadBehavioral responses:The results showed that F. arisanus obviously tended to the volatile things of the eggs and secretion of B. dorsalis, damage guavas. Male and female bees for the damaged guavas' trend rate reached 66.67% and 56.67% respectively, but they did not show trend to the healthy guavas. The trend changed being treated 1,000 times of spinosad.EAG reaction:The reaction of eggs' extract, the females of F. arisanus by different treatments had no obvious difference in the response of EAG. Difference was very significant between the normal males and the normal males treating by the sublethal dose of spinosad. In addition to the control, EAG response value to the eggs' extract of different treatments of F. arisanus were significant differences between male and female bees.The reaction of secretions extract, the females of F. arisanus by different treatments had obvious difference in the response of EAG. Difference was very significant between the normal males and the normal males treating by the sublethal doseof 1000 times and 2000 times of spinosad. Different treatment of F. arisanus EAG response value of secretion extract between male and female bees differences were very significant.The reaction of female abdominal extract, difference in response to EAG was extremely significant between the female treating by the sublethal dose of 3000 times and the females treating by the sublethal dose of 1000 times and 2000 times of spinosad. The EAG response value were extremely significant between the male treating by the sublethal dose of 2000 times and the females treating by the sublethal dose of 1000 times and 3000 times of spinosad. EAG response value of female abdominal extract between male and female bees differences were not significant.3) The effect to F. arisanus of low temperatureThe cocoons of different age of F. arisanus were preserved different time under different temperature which influenced the emergency of rate. The adults of F. arisanus and their 9 day-old cocoons on sublethal temperature and linear fitting were also studied through indoor simulation of low-temperature in this article. It revealed that along with the increase of day age pupa, they can resist lower and lower temperature. If tthe age of pupa is 6 day-old, it is best to keep in 16℃which can save 20 days . If the age of pupa is 9 day-old, it can put in lower temperature of 13℃to save. But after the 9 day-old pupa were kept under the 13℃, the parasitic rate after sexual maturity of adults was declined with the increse of preservation time. Results also showed that under different temperatures females'LT50 and males'LT50 were respectively 6.6149 days and 5.0274 days in 4℃, 8.1235 days and 5.7294 days in 7℃, 9.6161 days and 5.3221 days in 10℃, 5.0257 days and 2.7880 days in 13℃. And mortalities had experienced drastical process during aboved temperatures. LT50 of nine day-old pupa in different temperatures were 8.4172 days, 8.1235 days, 13.9949 days, 18.4107 days with 4, 7, 10 and 13℃respectively. The relationship between emergence rate and preservation days under the same temperature could be simulated by square curve equation. Studies suggested that pupa had a higher freezing-tolerance than female adults, so the former could be used as insect cryopreservation state.4) The effect to F. arisanus of variable temperature, variable temperature and wetIn the variable temperature, variable temperature and wet conditions, different weather conditions on different date influenced the hatch rates, emergence rate, adult parasitic rate and offspring sexual of F. arisanus. Results showed that: variable temperature, variable temperature and wet did not effect on the eggs hatch rates; different approaches influenced the total number of emergence, the emergence number from high to low was that the first was in the 25℃, the second was in the variable temperature, the third was in the variable temperature and wet; the influence to the number of bees emergence was the same.The adult parasitic rate of F. arisanus which was rasied in 25℃had difference. The parasitic rate from high to low was respectively in the conditions of variable temperature treatment and wet, variable temperature treatment and wet and contrast in different date.
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