八种热带、亚热带豆科植物根瘤菌内源质粒的分布情况

Diversity of Plasmid Profiles of Rhizobia Isolated from Eight Tropical and Subtropical Legumes

从８种热带、亚热带豆科植物中分离出９种快生型根瘤菌，用双梳子胶内裂解法检测其中的质粒分布情况。质粒数从１到６个不等，大小从３２ｋｂ到８７０ｋｂ，其中至少有一个分子量小于１００ｋｂ的质粒。从不同种属的豆科植物中分离出的根瘤菌，其质粒的数量及分子量各不相同。

Nine Rhizobium strains，isolated from eight species of tropical and sub-tropical legumes，were examined for plasmid content．Each of the fast－growing straintested contained 1～6 plasmids wjth molecular weight from 32 kh to B70 kb．At least oneof these plasmids was small(molecular weight was less than 100 kb)，and three strainscontained only one small plasmid(molecular weight was less than 50kb).The plasmidprofiles of Rhizobia from each species of the tropical and subtropical legumes were di- verse.