Survival Ability In Soil And The Promoting Effects Of The Growth Promoting Rhizobacteria Of Curcuma Wenyujin

In this experiment, the abilities of phosphorus dissolving, IAA and pathogen inhibition ability of38rhizosphere bacteria strains from the rhizosphere of Curcuma wenyujin were tested. Among these strains8strains secreted IAA above100mg/L,23strains produced siderophore at10+, and19strains dissolved phosphorus above150mg/L. Five strains had inhibitory effect on one wheat pathogen Fusarium sp.,4strains inhibited corn plaque fungy,3strains against rice sheath blight, and13strains against Fusarium oxysporum, and3strains had inhibitory effect on all4plant fungus pathogens (WP0702, WK0801and WK0802).Finally three strains (WP07023, WK0101and WN02) were selected for pot experiment. Strain WP0702secreted siderophore at high concentration, inhibited the growth of pathogens; strain WK0101secreted high concentration of siderophore and IAA, dissolved high amount phosphorus, but had no antifungus ability. The two strains could promote Curcuma wenyujin yield obviously. It proves that strains which have the abilities to dissolve phosphorus, secrete IAA and inhibit fungus pathogens, have the possibility to be used as biological fertilizer.Strains WP0702marked with marker gene luxAB could survive in different soil. Both WP0702and WK0101have the potential as specific biological fertilizer for Curcuma wenyujin. Eight strains could grow in medium which ACC as sole carbon source. The gene luxAB was transformed into WP0702strains by electroporation. The optimum growth temperature and pH of WP0702-/luxAB were not changed remarkably. The luxAB could stably exist in WP0702strains. WP0702-/luxAB strain could survival stably in sandy loam soil and cinnamon soil.Some physiological and biochemical indexes and16S rDNA sequences were determined experimentally, eventually7strains of bacteria were identified. WK0101is Enterobacter ludwigii; W8, Leclercia adecarboxylata; WP02, Enterobacter oryzae; WN02Burkholderia cenocepacia; WP0702, Burkholderia ubonensis; WP05, Klebsiella variicola; and WN0102, Enterobacter radicincitans.