应用RAPD分子标记技术研究苜蓿根瘤菌的田间竞争结瘤能力

Study on competitive nodulation ability of Rhizobium meliloti in field test by using RAPD Molecular Marker Method

以在温室条件筛选出与 Vector苜蓿品中匹配较好的根瘤菌系 CCBAU30 1 38和 Vector为材料 ,应用 RAPD技术研究CCBAU30 1 38田间竞争结瘤能力。结果显示 ,利用冻融法处理的根瘤、菌体提取的 DNA可以直接作为 PCR扩增的模板 ,扩增结果与以类菌体 DNA及总 DNA作为模板处理的结果相同 ;以根瘤处理物作为 PCR扩增的模板 ,应用 RAPD分子标记技术对接种菌 CCBAU30 1 38田间竞争结瘤能力进行研究 ,接种 1 4 0 d后 ,CCBAU30 1 38田间占瘤率为 4 7.7% ,表明该菌具有较强竞争结瘤能力和持久力。试验结果还说明 ,在接种菌与土著菌有差异的条件下 ,应用 RAPD技术开展竞争结瘤能力研究 ,可以直接以根瘤处理物作为 PCR扩增的模板 ,具有简易、快速。

CCBAU30138 was the most effective Rhizobium strains in nitrogen fixation screening for Vector cultivar in greenhouse. Study on competitive nodulation ability of CCBAU30138 strain in field test by using RAPD Molecular Marker Method. The results showed that: DNA extracted from nodules and strains by freeze- thaw bacterial cell lysates could be amplified as template for PCR, the same as the total DNA from strain and root nodules. RAPD-PCR amplification of Rhizobium meliloti DNA obtained from nodules isolates that were collected 140days after inoculating in the field, the nodule occupancy of CCBAU30138 strain was 47.7%. The result indicated that CCBAU30138 have high competitive abilities and persistence. In general, the results suggested that RAPD Molecular Marker Method was a good method to differentiate the studied strain when the strain has different profiles with the indigenous strains, and it is an easy, rapid and accurate method for the research on ecology and effective strains screen for Rhizobia.