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连续两年在田间自然状态下,采用PCR-DGGE方法研究6个不同生育期种植转Bt基因玉米MON810对根际土壤细菌群落遗传多样性的影响。结果表明,2008年,同一生育期内转Bt基因玉米与非Bt基因玉米根际土壤细菌16S rDNA DGGE指纹图谱相似,细菌群落的遗传物质组成差异不显著,仅在抽丝期和乳熟期Bt玉米出现两条差异条带。2009年,苗期、拔节期、喇叭口期、抽雄期4个生育期两种玉米出现差异条带,抽丝期和乳熟期无差异条带。对DGGE图谱条带进行克隆测序,部分图谱中的条带所代表的DNA序列相同,最终得到51条DNA序列,共涉及主要细菌门类8个,典型差异条带分别属于芽单胞菌门(Gemmatimonadetes)、变形菌门(Proteobacteria)、厚壁菌门(Firmicutes)。总体来看,与不同品种相比,不同生育期、不同年份间细菌群落差异更为显著,Bt蛋白的积累对根际细菌群落变化有一定影响。
The effect of transplanting transgenic Bt corn MON810 on the bacterial community diversity in rhizosphere was studied by PCR-DGGE in two consecutive years under field conditions. The results showed that the fingerprints of 16S rDNA DGGE in rhizospheric soil of transgenic Bt corn and non-Bt corn in the same growth period were similar in 2008, but there was no significant difference in the genetic composition of bacterial community. Only in Bt Corn appeared two different bands. In 2009, the two maize varieties at seedling, jointing, trumpet and tasseling stages showed differential bands, and there was no difference in the spinning and milking stages. The DGGE bands were cloned and sequenced. The DNA sequences of the bands in the partial maps were the same. Finally, 51 DNA sequences were obtained, involving a total of 8 major bacterial species. The typical differential bands belonged to Gemmatimonadetes Proteobacteria, Firmicutes. Overall, compared with different varieties, bacterial community differences were more significant at different growth stages and years, and the accumulation of Bt protein had some effects on the changes of bacterial community in rhizosphere.