非抗虫转基因棉花对土壤细菌群落多样性的影响

田间试验条件下,为了探究非抗虫转基因棉花对土壤细菌群落多样性的影响,应用PCR-DGGE技术对转RRM2基因高产棉、转GAFP基因抗病棉、转ACO2基因优质棉及非转基因常规棉(中棉所12)种植后在吐絮期的土壤细菌群落多样性进行分析。结果表明,与常规棉相比,3种转基因棉的种植均未对土壤细菌香农-威纳指数(H)、均匀度(EH)和丰富度(S)造成显著影响,且两类棉花土壤细菌群落结构相似性较高。可见,短期内,非抗虫转基因棉花的种植对土壤细菌群落多样性无显著影响。对DGGE的优势条带序列分析发现,同源性最高的微生物分别属于拟杆菌门(Bacteroidetes)的黄杆菌纲(Flavobacteria)、噬弧菌属(Bacteriovorax)、Segetibacter,变形菌门(Proteobacteria)的α-变形菌纲(alpha proteobacterium)、地杆菌属(Geobacter),厚壁菌门(Firmicutes)的Paenisporosarcina,酸杆菌门(Acidobacterias)的酸杆菌属(Acidobacterium),它们均为不可培养微生物。

Effects of Insect Non-resistant Transgenic Cottons on Bacterial Community Diversity in Soil

There are increasing public concerns over the ecological risks of transgenic plants. Under field conditions, the diversity and composition of bacterial community in soils grown with three insect non-resistant transgenic cottons(high-yield transgenic cotton expressing the RNA recognition motif 2 gene, disease-resistant transgenic cotton expressing the gastrodia antifungal protein and high-quality transgenic cotton expressing the 1-aminocyclopropane-1-carboxylate(ACC)oxidase]) and one conventional cotton CCRI 12(as control) were evaluated at the boll-opening stage by denaturing gradient gel electrophoresis(DGGE). The results showed that planting three transgenic cottons did not show significant effects on Shannon-wiener index(H), evenness(E_H) and richness(S) of soil bacteria. High degree of similarity in community structure was observed between transgenic and conventional cottons, indicating no influence of transgenic cottons on bacterial community diversity in the short term. High-yield RRM2 transgenic cotton, disease-resistant GAFP transgenic cotton, high-quality ACO2 transgenic cotton and conventional cotton had 67% similarity in community levels and were thus regarded as one group. According to the sequence analysis of DGGE dominant bands, microorganisms which presented the highest homology belonged to families of Flavobacteria, Bacteriovorax, Segetibacter, alpha proteobacterium, Geobacte, Paenisporosarcina, and Acidobacterium, respectively, and all of them were not cultivatable.