Growth conditions of endophytic diazotroph isolated from Cynodon dactylon

Effects of environmental factors on the growth of endophytic diazotroph strains 7D and BM13 isolated from Cynodon dactylon were investigated in our experiment. In this study, strains 7D and BM13 were examined for their adaptability to the stress of temperature, pH, NaCl, N4+, NO3- and carbon sources by Ashby media. The results showed that the two strains could grow under wide range of temperature of 10~40 ℃ and pH from 3.92~9.64. The strains could also tolerate NaCl concentrations of 30 g·L-1, N4+,and NO3- concentrations of 0~10 mmol·L-1, respectively. The strains were capable of using various carbon sources. It was suggested that the strains 7D and BM13 had superior tolerance to stress of diverse environment factors, but their tolerance abilities differed partly. Endophytic diazotroph strain is a candidate to be further developed for microbial fertilizer production.