摘要
黄土高原位于我国内陆,气候比较干旱,生长的植被较少,水土流失严重,而有些豆科植物如锦鸡儿(Caragana sinica)、苦豆子(Sophora alopecuroides)、甘草(Glycyrrhiza uralensis)、苦马豆(Swainsoniasalsula)、洋槐(Robinia pseudoacacia)等却能很好生长.这些豆科植物的生长,在防风固沙、保持水土、绿化环境、作为饲用牧草等方面起着很重要的作用.但人们对于黄土高原野生豆科植物根瘤菌的研究尚很少.为此,作者在地处黄土高原的陕西、宁夏及甘肃的部分地区进行了广泛的根瘤菌资源调查.在此基础上,对分离的部分菌株进行了数值分类和DNA同源性分析.
Thirty-five new rhizobial isolates from the loess plateau of China and 32known strains representing all known species of Rhizobium and Bradyrhizobium werecharacterized by numerical taxonomy and DNA analysis. New strains were mainlyisolated from the nodules of genera Amorpha, Camilla, Amblytropis, Caragana,Amphicarpaea, Glycyrrhiza, and Sophora. The results of numerical taxonomy based on208 phenotypical features showed that all tested strains were divided into 3 groups above72% similarity level. They were fast growing rhizobia, slow-growing rhizobia and amoderate-slow-growing group (generation time was above 5 hr). Most of new isolatesfell in 5 distinctive subgroups, differing from all known species of root nodule bacteria.Three of the 5 new subgroups belonged to Rhizobium, One of them belonged toBradyrhizobium. Another moderate-slow-growers were similar with a proposed newspecies, R. tianshanense. The analysis of DNA-DNA hybridization indicated that one(subgroup 7) of the 3 fast growing subgroups belonged to Rhizobium loti, and the otherswere new DNA homologous groups, differing from all known species. The exacttaxonomic positions of these new subgroups will be determined by further studies.
出处
《微生物学报》
CAS
CSCD
北大核心
1995年第3期223-228,共6页
Acta Microbiologica Sinica
基金
国家自然科学基金资助重点项目
关键词
根瘤菌
分类
数值分类
DNA杂交
黄土高原
Loess plateau, Rhizobium, Numerical taxonomy, DNA-DN A hybridization.
