百草枯对巨桉人工幼林土壤细菌多样性的影响  

Effect of paraquat on soil bacteria diversity in a young eucalypt plantation

作　　者：何伟[1] 吴福忠[1] 杨万勤[1] 王奥[1] 武志超[1] 赵野逸[1] 

机构地区：[1]四川农业大学生态林业研究所、林业生态工程重点实验室,成都611130

出　　处：《环境科学学报》2012年第11期2857-2864,共8页Acta Scientiae Circumstantiae

基　　金：国家“十二五”科技支撑计划(No.2011BAC09B05);四川省科技支撑计划(No.2010NZ0051);四川高等学校科技创新重大培育计划(No.2007ZZ024,09ZZ023);四川省青年基金项目(No.2012JQ0008)~~

摘　　要：为了解百草枯对土壤微生物多样性的影响过程和时效,在施加百草枯后第0、1、2、4、8、15、31d动态采集四川盆地典型巨桉人工幼林表层土壤,采用PCR-DGGE方法研究了细菌群落多样性特征.结果表明,施加百草枯后第1d土壤细菌丰富度显著降低,但在第2d明显增加,随后在第4d和第8d出现一个降低的过程,直至第15d降至最低点,在第31d又显著增加.施用百草枯后明显降低了土壤细菌群落Shannon-Wiener指数,但增加了Simpson指数,表明百草枯的施加可使部分细菌减少或丧失,土壤细菌群落结构表现出较高的优势度和较低的丰富度.通过对优势条带的克隆测序,鞘脂杆菌科(Sphingobacteriaceae)和酸杆菌纲(Acidobacteria)普遍存在于施加百草枯前后的不同阶段,而施加百草枯后第1d伯克氏菌目(Burkholderiales)和γ-变形菌纲(Gamma-proteobacteria)条带消失,随后均在第2、4和8d出现,但15d后伯克氏菌目、α-变形菌纲(Alpha-proteobacteria)和γ-变形菌纲条带消失,第31dγ-变形菌纲条带仍然缺失.这些结果为更清晰地认识百草枯对土壤微生物的影响提供了基础数据.To understand the effect of paraquat on soil baelerial community, the diversity of soil bacterial community were investigated after paraquat application in a young eucalypt （ Eucalyptus grandis） plantation by Polymerase Chain Reaction Denature Gradient Gel Electrophoresis （PCR-DGGE） method. Soils were sampled after the application at initial, the 1^st, the 2^nd, the 4^th, the 8^th, the 15^th, and the 31^st day. The results showed that the richness of soil bacteria significantly decreased on the 1^st day after paraquat application, but increased on the 2^nd day. After that, the richness of soil bacteria continually reduced to an obvious valley value on the 15^th day, and then increased on the 31^st day. Moreover, paraquat application reduced Shannon-Wiener index but increased Simpson index of soil bacterial community, indicating that paraquat could inhibit even kill some parts of the bacteria. According to the analyses of clones and DNA sequence on the advantage bands, Sphingobacteriaceae and Acidobacteria were always present in all soil samples from different days after paraquat application, but Burkholderiales and Gamma proteobacteria disappeared on the 1^st day and appeared on the 2^nd , the 4^th and the 8^th day. Further, Burkholderiales, Alphaproteohacteria and Gamma proteobacteria disappeared on the 15^th day after paraquat application, and Gamma proteobacteria was also not detected on the 31^st day. These results provided basic data to understand the effects of herbicides like paraquat on soil microbial community in a young eucalyptus plantation in West China.

关 键 词：百草枯 PCR—DGGE 16S rDNA V3区 细菌群落 

分 类 号：X53[环境科学与工程—环境工程]