Screening of high efficient symbiotic rhizobial strains of Alfalfa by soil test

The effects of inoculation with 12 rhizobial strains on two Medicago sativacultivars were conducted by soil test, aimed at screening the efficient symbiotic strains for each cultivars under a condition closed to the field. The results showed that most of rhizobial strains promoted the plant growth of both cultivars. Compared with the controls, the numbers of total nodules of alfalfa plants inoculated with rhizobium increased by 7%~240%, the numbers of effective nodules increased by 10%~367%, and the aboveground dry weight increased by 7%~150%. Significant interaction existed between the alfalfa cultivars and the rhizobial strains tested, symbiotic effects were influenced by soil conditions obviously, especially the status of soil fertility. The tested alfalfa cultivars ZhongMu No.1 and Golden Empress showed better growth performance inoculated with the strains 73317, 01006, 01055 and 83092, 01006, 01055 respectively.