目前,筛选根瘤菌的方法很多,但均以固氮活性为初选指标。我们以竞争力为初选指标,自1978—1979年用混合根瘤竞争接种后再分离方法,在分离纯化前针对一定的大豆品种,完成竞争力测定和选择。与常规分离纯化筛选方法相比,可显著提高筛选工作效率,现将具体方法整理如下: At present, there are many ways to screen rhizobia, but nitrogen fixation activity is the primary index. We use the competitiveness of the primary indicators, from 1978 to 1979 with mixed nodules competition after inoculation and then separation method, before the isolation and purification of certain soybean varieties, to complete the competitiveness determination and selection. Compared with the conventional separation and purification screening method, can significantly improve the screening efficiency, the specific method is now organized as follows: