磷高效转基因水稻OsPT4种植对土壤细菌群落多样性的影响

Diversity of bacterial community in rice paddy soil grown with P-efficient transgenic rice(OsPT4)

为探讨磷高效转基因水稻种植对土壤细菌多样性的影响,在小区试验条件下,以磷高效转基因水稻Os PT4为对象,以非转基因水稻日本晴、磷高效突变体水稻PHO2为对照,设施磷和不施磷两种处理,采用PCR-DGGE测序技术,分析比较了磷高效转基因水稻Os PT4在整个生长期对土壤细菌群落丰富度、均匀度的影响。结果显示,同一处理、同一生长期内磷高效转基因水稻Os PT4、磷高效突变体水稻PHO2与常规水稻日本晴的土壤细菌16S r DNA DGGE指纹图谱基本相似;施磷处理条件下,PHO2在拔节期较Os PT4、日本晴增加一条电泳条带,该条带属于蓝藻菌门(Cyanobactteria)藻青菌属(Cyanobacterium),Os PT4在抽穗扬花期较日本晴缺失一条电泳条带,该条带属于芽单胞菌门(Gemmatimonadetes);不施磷处理时,Os PT4在分蘖期和成熟期较日本晴增加4条电泳条带,测序结果显示分别为变形菌门(Proteobacteria)地杆菌属(Geobacter)、厚壁菌门(Firmicutes)芽孢杆菌属(Bacillus)、绿弯菌门(Chloroflexi)、变形菌门(Proteobacteria)和地杆菌属(Geobacter)。研究表明,在水稻个别生长期,磷高效转基因水稻Os PT4对土壤细菌丰富度(S)、香农-威纳指数(H)和均匀度(EH)产生显著影响。

The effects of genetically modified crops（GMCs）on soil microbial community have been received more and more attentions in recent years. In this study, the effects of P-efficient transgenic rice（OsPT4）on richness and evenness of soil bacterial community were compared with parental OsPT4（Nipponbare）and P-efficient mutant rice（PHO2）, using denaturing gradient gel electrophoresis（DGGE）technique. Two phosphorous（P）application rates（0 and 15 g·m-2）were used. The bacterial 16 S r DNA DGGE fingerprintings had no significant differences in community structure between P-efficient transgenic rice, Nipponbare and P-efficientmutant rice at the same P rate during the same growing stage. Under P application, PHO2 had one more electrophoretic band than OsPT4 and Nipponbare did at the elongation stage.This increased band belonged to Cyanobacterium of Cyanobactteria. At the heading and flowering stages, OsPT4 had one less electrophoretic band than Nipponbare did. This missed band was a part of Gemmatimonadetes. Under no P application, OsPT4 emerged four electrophoretic bands during both tillering and maturing stages, as compared with Nipponbare. These four electrophoretic bands were associated with Geobacter of Proteobacteria, Bacillus of Firmicutes, Chloroflexi, and Geobacter of Proteobacteria. This study demonstrates that P-efficient transgenic rice（OsPT4）has significant effects on richness（S）, Shannon-wiener index（H）and evenness（EH）of soil bacteria at certain rice growth stages, and that P fertilizer may also be involved in these effects.