Inoculation effects of five rhizobial stains to alfalfa

Five saline tolerance rhizobial strains (Sinorhizobium meliloti, ACCC17537,ACCC17558,ACCC17617,ACCC17631 and ACCC17676) were inoculated on Medicago sativa cv. Zhongmu No.1 by two inoculation methods in field to screen high efficient rhizobia and inoculation method in coastland. Seed coating and liquid inoculant without rhizobial strains were also included as controls. The results showed that seed coating method was better compared with liquid inoculants if Zhongmu No.1 grew in soil with serious salinization and lack of rhizobia. There were significant difference between the effects of five rhizobial strains on Zhongmu No.1 by seed coating. Dry weight, crude protein, the numbers of total nodules and effective nodules of alfalfa plant inoculating with 5 rhizobial strains significantly increased (P＜0.05) compared with the controls. The effects of ACCC17558 and ACCC17617 on alfalfa were highest. Dry weight, total nodules, effective nodules and crude protein of per alfalfa inoculating with ACCC17558 and ACCC17617 increased 91.4% and 164.4%, 91.8% and 99.6%, 99.8% and 100.7%, 8.6% and 12.3% compared with the control, respectively. The strains of ACCC17558 and ACCC17617 were selected as good inoculants for Zhongmu No.1 alfalfa in saline soil.