부산대학교 도서관

To authenticate to the full-text of this article, please visit this link: http://dx.doi.org/10.1111/j.1574-6941.2009.00752.x Byline: Yan Mei Sun (1), Nan Nan Zhang (1), En Tao Wang (2), Hong Li Yuan (1), Jin Shui Yang (1), Wen Xin Chen (1) Keywords: bacterial community; microbial biomass; enzyme activity; intercropping; rhizobial inoculation; rhizosphere Abstract: Abstract Alfalfa-Siberian wild rye intercropping is the predominant cropping system used to produce forage in China. In this study, the effects of intercropping and intercropping-rhizobial inoculation on soil enzyme activities, microbial biomass and bacterial community composition in the rhizosphere were examined. In both treatments, the yield of alfalfa, microbial biomass and activities of soil urease, invertase and alkaline phosphatase in the alfalfa rhizosphere were markedly increased, whereas there was a slight increase in the yield of Siberian wild rye, few impacts on soil microbial biomass, and decreased enzyme activities (except for urease) in the Siberian wild rye rhizosphere. Terminal restriction fragment length polymorphism (T-RFLP) of 16S rRNA genes indicated that Alphaproteobacteria, Betaproteobacteria, Gammaproteobacteria, Deltaproteobacteria, Firmicutes, Actinobacteria and Bacteroidetes were the major bacterial groups in the rhizosphere of both plants. However, intercropping and rhizobial inoculation induced some shifts in the relative abundance of them. Nitrosomonas and Nitrosospira groups were detected in all treatments by the T-RFLP patterns of ammonia monooxygenase subunit A (amoA) gene, but the relative abundance of Nitrosomonas increased and that of Nitrosospira decreased in the intercropping-rhizobial inoculation treatment. Both treatments tended to increase the diversity of amoA. Conclusively, the two treatments clearly affected soil microbial composition and soil enzyme activities, which might be reflected in changes in yield. Author Affiliation: (1)State Key Laboratory for Agrobiotechnology, College of Biological Sciences and Center for Biomass Engineering, China Agricultural University, Beijing, China (2)Departamento de Microbiologia, Escuela Nacional de Ciencias Biologicas, Instituto Politecnico Nacional, Mexico, DF, Mexico Article History: Received 4 March 2009; revised 28 June 2009; accepted 6 July 2009.Final version published online 24 August 2009. Article note: Correspondence: Hong Li Yuan, State Key Laboratory for Agrobiotechnology, College of Biological Sciences and Center for Biomass Engineering, China Agricultural University, Beijing 100193, China. Tel.: +86 10 62 73 3464; fax: +86 10 62 73 4008; e-mail: hlyuan@cau.edu.cn