| An investigate was conducted on leguminous plants and rhizobial resources in some regions of Qinghai,Gansu,Ningxia and Shaanxi in Northwest China,in which a total number of 1850 root nodule samples were collected,including 20 genera,41species of cultivated and wild legumes legumes.In the samples,86% of the root nodules were distributed on lateral root or fibre, and they were shaped as claviform,palmated,coralliform or spherical,most in colors of yellow and pink,and few in white and brown.Investigation and research results found that,Oxytropis ningxiaensis.C.W.Chang is a new discovered leguminous plant,which could be nodulation,and Oxytropis xinglongshanica C.W.Chang is a new record to Qinghai.Besides related to the genetic characteristics and development period of host plants,legume symbiosis nodulation with rhizobia and nodule characteristics has close relation to its ecological environment,including moisture,temperature,sunlight,soil structure,soil pH,etc.It would provide a scientific basis for the development and utilization of rhizobia germplasm resources. |