利用根箱法解析转双价(Bt+CpTI)基因棉花对土壤微生物数量及细菌多样性的影响

Effects of Transgenic Bt +CpTI Cotton on the Soil Microbial Amount and Bacterial Diversity by Rhizobox Method

利用根箱法对棉花根部土壤进行分区采集,并采用传统平板培养和DGGE克隆测序技术相结合的方法,对转双价基因棉和常规棉3个生长时期(播种后40 d、50 d和60 d)不同根区土壤细菌、放线菌和真菌数量及细菌多样性进行对比分析。平板培养结果表明,与常规棉相比,转双价基因棉S1根区土壤细菌、放线菌的数量显著降低,而S2根区土壤细菌、放线菌、真菌和S3根区土壤细菌、真菌的数量显著增加(P<0.05);DGGE图谱分析表明,在棉花生长的3个时期内,转双价基因棉和常规棉根区土壤细菌多样性指数、均匀度和条带数均无显著差异(P>0.05),2种棉花处理间有着很强的相似性,不受转双价基因棉种植的影响。转双价基因棉种植仅改变了根区土壤可培养微生物数量,对细菌多样性无显著影响。

In this study,three-room rhizobox method was used to collect soil samples from different zones of cotton root.Traditional culture-depending methods and DGGE-cloning sequencing were used to investigate the different soil microbial（bacteria,actinomycetes,fungi） amount and bacterial diversity between transgenic Bt ＋CpTI cotton and conventional cotton in three growing stages（40 d,50 d and 60 d）.The results of traditional culture-depending method showed that the amount of soil bacteria and actinomycetes decreased significantly in S1 zone of transgenic Bt ＋CpTI cotton,but the amount of three microorganisms in S2 zone and the amount of bacteria and fungi in S3 zone of transgenic Bt ＋CpTI cotton increased significantly,compared to the conventional cotton.DGGE fingerprinting indicated that the Shannon-Wiener index,evenness and the number of bands had no significant difference between transgenic Bt ＋CpTI cotton and conventional cotton in three growing stages.There was high similarity between the two cotton treatments and it was not affected by the planting of transgenic Bt ＋CpTI cotton.The planting of transgenic Bt ＋CpTI cotton only affected the amount of microorganisms and had no significant effect on the bacterial diversity.