Screening of Multifunctional Growth-promoting Bacteria in Tree Peony Rhizosphere and Analysis of Their Promoting Potential
The rhizosphere soil of tree peony was used as the experimental material,the tree peony rhizosphere growth promoting bacteria were isolated and purified by the screening medium.The growth promoting characteristics of the screened strains,such as nitrogen fixation,phosphorus solubilization,indole-3-acetic acid(IAA)secretion,iron carrier production,and 1-aminocyclopropane-1-carboxylic acid(ACC)deaminase activity,were studied.At the same time,pot cultivation experiments were used to analyze the growth promoting effect of the screened strains on Chinese cabbage seedlings,in order to screen strains with multiple growth promoting functions from the tree peony rhizosphere and provide reference and excellent bacterial resources for the development of efficient microbial agents.The results showed that eight composite growth promoting strains were screened from the tree peony rhizosphere soil.Among them,N3,P2,and N16 showed the ability of nitrogen-fixing,phosphate-dissolving,siderophore and IAA production.The highest content of IAA secreted by N3 was 27.90 mg·L-1.P2 showed the strongest ability to dissolve inorganic phosphorus,and the ratio of the phosphorus solubilizing circle diameter and colony diameter(D/d)was 3.77.Other strains(L1,L5,L10,K5,and N26)all showed two or more growth promoting characteristics.The 16S rDNA sequencing and phylogenetic analysis of these strains indicated that N3 and P2 belonged to the genus Pantoea,L1,L5 and K5 belonged to the genus Pseudomonas,N16 belonged to the genus P seudoxanthomonas,L10 and N26 belonged to the genus Agrobacterium.The results of the pot experiment showed that four representative strains had a certain promoting effect on the growth of Chinese cabbage,indicating that tree peony rhizosphere promoting bacteria had the potential to prepare microbial fertilizers.
tree peonygrowth-promoting rhizobacteriagrowth promoting characteristicsmicrobial fer-tilizers
NETL
NSTL
万方数据
