新疆耐盐苜蓿根瘤菌的分离和高效菌株的筛选  

Isolation of Salt-tolerant Sinorhizobium meliloti in Xinjiang and Screening for High-efficient Strains

作　　者：熊志锐[1] 张新宇[2] 王永宝[1] 徐永生[2] 耿卫东[2] 孙杰[2] 

机构地区：[1]石河子大学生命科学学院,新疆石河子832000 [2]石河子大学/新疆兵团绿洲生态农业重点实验室,新疆石河子832003

出　　处：《新疆农业科学》2009年第6期1301-1306,共6页Xinjiang Agricultural Sciences

基　　金：国家自然科学基金项目(30570132);石河子大学新疆兵团绿洲生态农业重点实验室开放课题(200503)

摘　　要：【目的】人工接菌苜蓿根瘤菌和筛选高效菌株。【方法】采集新疆14个地州不同生态区、不同类型土样132份,采用苜蓿捕获法分离、纯化获得81个苜蓿根瘤菌菌株。【结果】快速PCR检测鉴定发现,分离得到的根瘤菌菌株均属于苜蓿中华根瘤菌（Sinorhizobium Meliloti）。【结论】耐盐实验表明,这些菌株在YMA培养基上的耐盐能力在3.5%~5%NaCl,进一步分析发现土壤中盐含量与苜蓿根瘤菌的耐盐能力没有明显的相关性。对耐5%NaCl的8个根瘤菌菌株的16S rDNA序列进行分析,发现这些其序列同源性很高,相似性达到99.8%。根瘤菌接种实验表明,这8个菌株均能明显增加紫花苜蓿植株地上部分生长,但不同菌株其固氮效率存在显著差异,其中TC-Y菌株共生固氮效率最高。【Objective】In this study,Sinorhizobium populations were isolated from 14 different regions in Xinjiang,using Medicago sativa as trap host plants.【Method】A total of 81 rhizobial isolates were obtained and were confirmed that all of them fell into S.meliloti by PCR.【Result】Analysis of salt tolerance revealed that they can survive in YMA medium whose salt tolerance was between 3.5% to 5% NaCl,and there was no apparent correlation between salt tolerance in Sinorhizobium meliloti and the salt content of the soil samples.【Conclusion】The 16S rDNA sequence of 8 isolates,which had salt tolerance to 5% NaCl,were high,its similarity was high and reached 99.8%.The innolation test indicated that all the 8 isolates could increase the growth of aboveground part of alfalfa plant.Additionally,there is difference in the symbiotic nitrogen-fixing efficiency of these 8 isolates with alfalfa,and the nitrogen-fixing efficiency of TC-Y is higher than that of other isolates.

关 键 词：苜蓿中华根瘤菌 紫花苜蓿 耐盐 共生固氮效率 新疆 

分 类 号：S188[农业科学—农业基础科学] S812-05