【摘要】 在根际箱中种植2个转基因Bt棉品系99BC-4,99BC-8及其非Bt受体泗棉3(SM3)后,于花期采集其根际土壤,进行化学分析、微生物生物量测量、Bt毒蛋白检测和酶活性测定。结果显示,2品系的根际土壤内能检测出Bt毒蛋白。相比于受体,99BC-4或99BC-8根际土壤中N,Ca,Zn,Co和Cu元素含量高,而K,Mg元素的含量低,C/N,P和Mn的含量无显著差异;Fe元素,99BC-4根际土壤内含量低,99BC-8根际土壤内含量高。2个转基因Bt棉品系根际土壤内微生物生物量碳显著高于其受体,但微生物生物量碳与总碳量的比值,99BC-4与受体相比,有显著差异。不同根际土壤内磷酸酶活性无显著差异,但相比于受体,FDA水解酶活性99BC-4根际土壤内显著升高,而99BC-8显著降低。推断Bt毒蛋白的存在可能通过改变某些微生物的代谢模式来刺激它们的生长,而已变的代谢模式似乎主宰着土壤中微生物的反应,虽然其反应在2转基因Bt棉品系的根际土壤内可能会不一致。更多还原

【Abstract】 After cultivation of 2 transgenic Bt cotton lines,99BC-4 and 99BC-8,and their non-Bt recipient Simian3( SM3)in rhizoboxes,the rhizospheric soils during blooming period were sampled. By the chemical analysis,microbial biomass measurement,Bt toxic protein detection,enzyme activity determinations,this study revealed that the rhizospheric soils of99BC-4 and 99BC-8 were positive for Bt endotoxin content. N,Ca,Zn,Co and Cu contents had higher values in the rhizospheric soils of 99BC-4 /99BC-8 than in that of SM3 while lower values found with 2 Bt cotton lines for K and Mg contents.No significant differences( p > 0. 05) for C / N,P and Mn contents. For Fe content,a lower value was observed in 99BC-4rhizospheric soil whereas a higher value in that of 99BC-8. Cmic( microbial biomass C) with 2 transgenic Bt cotton lines showed higher values with significant differences( p < 0. 05). But for Cmic/ Ctotal,a significant difference( p < 0. 05) found between those of SM3 and 99BC-4 only. Compared with SM3,2 Bt cotton lines performed more or less inconsistently as no significant difference emerged for phosphatase,a higher value in 99BC-4 rhizospheric soils but a lower value in that of99BC-8 for FDA hydrolysis. It can be deduced that the presence of Bt endotoxin likely stimulated the growth of some microbes by altering their metabolic patterns,which seemed to dominate the microbial responses in the soil although the responses were inconsistent in 2 transgenic Bt lines.更多还原