The analysis on Rhizobium of Trifolium spp. by SDSPAGE and molecular verification of nodulation ability test

The whole cell protein SDSPAGE was a rapid, stable, accurate method to reflect protein molecules types in cells, it could be developed to perform primarily clustering of Rhizobium and verification of nodulation strains in nodulation ability test. 120 strains isolated from the root nodule of Trifolium spp. which were collected from six regions such as Yunnan, Hubei, Hebei, and so on. The clustering analysis of the whole cell protein SDSPAGE molecular marker showed that there were 104 types which clustered six groups at a similarity level of 80%. 42 strains were selected by strains characteristic and collection site etc. to carry out the nodulation test. The results showed that 42 Trifolium spp. plants with rhizobia inoculation could nodulate, and the nodulation rate was 100%. At the same time, some reisolated strains named nodulation strains gained by reisolated root nodule of representative strains partly. Then, we carried out the whole cell protein molecular marker between original strains and reisolates strains in same cultivation conditions. The clustering analysis demonstrated that 10 original strains had an identical protein maps with their reisolated strains at higher similarity, it indicated that these strains could establish symbiotic nodulation connection with their original Trifolium spp. hosts.