| Helicoverpa armigera are collected in cotton areas of XinJiang from 2008 to 2009.Base on an improved rearing method for Helicoverpa armigera and tested the concentration of Bt protein by spectrophotometer we determe them through F2 genetic method and log does in laboratory.The data are diposed by SPSS software.Comparing LC50 and frequency of Alleles Conferring Resistance,the result shows by follows.1. it showed that the protein provided by black mountain laboratory(Australia)is 20g/L.Based on a conventional aetificial diet and rearing teachnique for H.armigera,the authors simplified and improved the materials and operating proce.Reduce the disease,cut down the cost.2. Baseline susceptibility Of Helicoverpa armigera in Xinjiang to Cry1Ac Toxin. The results showed that the mean lethal concentrations(LC50)is 0.035μg/ml,it ranged from0.022μg/ml to 0.048μg/ml of diet;LC90 is 0.089μg/ml, it ranged from0.526μg/ml to1.333μg/ml of diet. The detection concentration (LC99)is 1.020μg/ml of diet. The analysis of 95% fiducial limits showed that the Helicoverpa armigera collected from the ten major cotton fields of Xinjiang were susceptible to Cry1Ac and varied mortality response to Cry1Ac protein.3. The detection of resistance to the Cry1Ac in xinjiang Populations of Helicoverpa armigera. The results showed that the mean lethal concentrations LC50 of Helicoverpa armigera in Xinjiang cotton fields ranged from 0.022μg/ml to 0.111μg/ml.All populations were susceptible to Cry1Ac. Helicoverpa armigera collected from the Bt cotton areas of Xinjiang fields have a higher LC50 than the conventional cotton areas. Kuerle area has the highest LC50 .it is the 3.36 times of the baseline, also is 5.05 times of manasi area. It is near the level of 5 times. LC50 of Bole area is 3.03 times of the baseline and 4.55 times of the manasi area. Adopt the F2 bioassay to test frequency of alleles conferring resistance to the Cry1Ac in xinjiang Populations. The result shows that we found two resistance genes in kuerle and the frequency of alleles conferring resistance is 1.476×10-3. The second is bole area,the frequency is 1.055×10-3, Frequency of resistance in Akesu area is 0.977×10-3.it is 1.000×10-3 in kashi area. it is no resistance genes be found in other places . There are no obviously different.The susceptibility of Helicoverpa armigera in Bt cotton areas have downtrend.some cotton areas get into a dangerous period.4. The toxicity determine of Helicoverpa armiger in five different cotton area to chemistry pesticide.It shows that the resistance of Helicoverpa armigera is higher in routine cotton areas than Bt cotton areas. To cypermethrin,Helicoverpa armiger in manasi area have a higher resistance. It rings from higher to lower is manasi,hutubi,kashi,akesu,kuerle.The LC50 is 2.338 mg/L,2.146 mg/L,2.089 mg/L,2.070 mg.L-1,1.960 mg.L-1.To endosulfan, Helicoverpa armiger in hutubi area have a higher resistance. It rings from higher to lower is hutubi, mansi,akesu,kashi,kuerle.The LC50 is 4.174 mg/L,3.502 mg/L,3.213 mg/L,2.952 mg/L,2.839 mg/L.
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