摘要
从大果紫檀根瘤中分离到一株慢生型根瘤菌DG,通过其形态特征观察、保守基因序列分析以及生物学特性研究等方面进行种类鉴定,通过结瘤试验了解DG与降香黄檀的共生关系,并探讨其共生固氮能力.16S rRNA、nifH和dnaK系统发育结果表明,该菌株与Bradyrhizobium elkanii同源性最高.菌株DG与B,elkanii USDA76T在碳源利用、抗生素抗性、耐受NaCl等生物学特性上基本一致,而且还能在pH 10.0下良好生长.结瘤试验显示,菌株DG能在降香黄檀根部结瘤;接种DG的降香黄檀幼苗植株的株高、干重以及全氮含量(P<0.05)显著高于对照处理,表明DG能与降香黄檀形成良好的共生关系,且具有高效的固氮能力.
One slow-growing rhizobium DG was isolated from nodule of Pterocarpus macarocarpus,and the strain was identified based on its conservative gene sequencing,and morphological and biological characteristics.Nodulation test was conducted to understand the symbiosis between strain DG and Dalbergia odorifera,and the nitrogen-fixation capacity of strain DG was investigated.The phylogenetic relationship based on the sequence analysis of 16S rRNA,nifH and dnaK genes showed that DG was mostly related to Bradyrhizobium elkanii.The biological characteristics of strain DG were the same as the type strain B.elkanii USDA76T in utilization of carbon as sole source,resistance to antibiotics and tolerance to NaCl,except that DG could grow well at pH 10.0.The nodulation test indicated that strain DG was able to form nodules on D.odorifera.Plant height,dry weight and total N in the inoculated plants were generally significantly higher than those in the plants of negative control（P0.05）.The results indicated that strain DG could form fine symbiosis with D.odorifera,and possessed efficient nitrogen-fixation capability.This study suggested that strain DG could be used as inoculants for the plantation of tropical legume trees.Fig 4,Tab 2,Ref 27
出处
《应用与环境生物学报》
CAS
CSCD
北大核心
2011年第3期379-383,共5页
Chinese Journal of Applied and Environmental Biology
基金
广东省林业科技创新专项资金项目(No.2009KJCX002-01)资助~~
关键词
根瘤菌
降香黄檀
结瘤
固氮作用
共生关系
rhizobium
Dalbergia odorifer
nodulation
nitrogen fixation
symbiosis
