Screening of Growth -Promoting Bacteria from Euryale ferox Rhizosphere and Their Biological Characteristics

Zhang Yi; Cheng Xiao; Wang Quanlong; Liu Shujie; Wu Bingqi

doi:10.14083/j.issn.1001-4942.2015.08.014

Abstract：This study aims to provide excellent bacterial strain resources for the production of Euryale fer-ox bio -fertilizer.Two strains with relatively higher performance named Q6 -2 and Q67 were screened from the rhizosphere soil of Euryale ferox using the methods of remaining green and radish cotyledon bioassay;their production capability of plant hormones and organic acids were quantitatively analyzed by HPLC;their promo-tion effects on the growth of Euryale ferox at seedling stage were investigated by pot experiments;also,they were identified by physiological and biochemical experiments and 16S rDNA sequence analysis.The results in-dicated that the two strains were both able to produce zeatin,kinetin and small amount of organic acid.Q6 -2 was also able to produce indoleacetic acid (IAA).After inoculated by Q6 -2,the growth parameters of Eury-ale ferox seedlings,such as stem length,number of leaves,maximum leaf area and biomass (dry weight), significantly increased by 18.85%,40.67%,76.28% and 37.50% respectively compared to the control;while inoculated by Q67,the above mentioned indexes significantly increased by 27.47%,42.81%, 96.05% and 42.97% respectively.After inoculated by Q6 -2 and Q67,the chlorophyll content increased by 43.27% and 51.46% respectively,and the root activity increased by 5.41% and 7.05% respectively,show-ing significant differences compared to the control.Q6 -2 and Q67 were both identified as Bacillus lichenifor-mis,whose GenBank accession number were KP686129 and KP686133 respectively.In conclusion,the two strains were able to promote the growth and development of Euryale ferox seedlings efficiently,showing great application prospect in the production of microbial fertilizer.