摘要
利用16S rDNA-RFLP和全序列测定方法,对分离自商洛地区5个分布点的59株多花胡枝子根瘤菌进行了RFLP分析和系统发育研究.结果表明:(1)42株供试菌株归属根瘤菌属(Rhizobium)、11株归属中华根瘤菌属(Sinorhizobium).其余6株非根瘤菌中3株是嗜麦芽黄单胞菌(Stenotrophomonas maltophilia)、3株是解淀粉类芽孢杆菌(Paenibacillus amylolyticus),说明胡枝子根瘤内生菌较为丰富且类型多样.(2)结合供试菌株的地理生境分析,发现来自不同采集点的菌株有些具有同样的遗传类型,而来自同一采集点的菌株遗传类型却有差异,证明胡枝子根瘤菌在分群类别上与地理环境之间没有明确的对应关系,地理环境并非根瘤菌多样性形成的主要因素.建议今后对根瘤菌多样性研究应从根瘤菌与寄主植物物之间的共生选择进化,特别是对共生体系中基因的横向转移方面进行深入探讨.
59 rhizobia isolated from Lespedeza floribunda in five different geographical sites in Shaanxi Shangluo region of China were studied by 16S rDNA-RFLP and sequencing analysis.The result revealed that 42 tested strains belong to Rhizobium,11 tested strains belong to Sinorhizobium respectively.In addition,there are six non-rhizobia,of which 3 strains are the Paenibacillus amylolyticus and 3 strains are the Stenotrophomonas maltophilia.The results show that rhizobia isolated from L.floribunda is abundant and has more diversity.Through further analysis of the geographical origin of isolated strains,it can be found that strains collected from the different sites have the same genetic types,but strains collected from the same sites have differenct genetic types.The results show that there is no obvious correlation between the grouping of Lespedeza rhizobia and the geographical environment,and the geographical environment is not the main factor determining the diversity formation of rhizobia.A deep study in symbiotic choice evolution between the rhizobia and its host plant,especially from the horizontal transfer of genes in symbiotic system is necessary in future to probe the causes leading to diversity of rhizobia.
出处
《西北植物学报》
CAS
CSCD
北大核心
2010年第5期925-932,共8页
Acta Botanica Boreali-Occidentalia Sinica
基金
国家自然科学基金(30900215
30970003)
