根瘤菌在土壤里的分布、存活、构成权瘤菌的自然区系,是根瘤菌生态学研究的重要内容之一,与根瘤菌的竞争性,根瘤菌株的使用及人工培育菌系的接种效果有十分密切的关系。Damigi、Ham等先后测定在美匡中西部土壤里血清型123是大豆根瘤菌的优势种;Brockwell对引入田间的三叶草菌系间的竞争做了研究;近几年曾对我国一些地区不同土类及种植不同大豆品种时,大豆根瘤菌在根瘤内的自然分布及在大豆不同生长期内的结瘤比例做了调查。1982年,H.H.Keyser等报告了从我国 The distribution and survival of rhizobia in the soil constitute the natural flora of the fungus, which is one of the important contents of rhizobium ecology research. The competition with rhizobium, the use of rhizobium strains and the inoculation effect of artificial breeding strains There is a very close relationship. Damigi, Ham et al. Determined that serotype 123 was the dominant species of soybean rhizobia in the mid-western U.S. soil; Brockwell studied the competition among the clover-type strains introduced into the field; in recent years, And the cultivation of different soybean varieties, the natural distribution of soybean rhizobia in nodules and nodulation in different growth stages of soybean were investigated. In 1982, H.H.Keyser et al. Reported from our country