Functional characteristics of Bacillus siamensis 37402-1 and its growth-promoting effect on garlic
Garlic(Allium sativum L.)is an important cash crop in China,but its planting and production sustainability is restricted due to serious continuous cropping obstacles in the main producing area.Plant growth promoting rhizobacteria(PGPR)can promote plant growth,control disease and promote the environment.It is of great ecological and practical significance for the sustainable development and green development of garlic industry to develop efficient microbial fertilizer for the prevention and control of garlic soil-borne diseases.The bacteria isolated from the root of continuous cropping garlic in Jinxiang county,Shandong province was used as the test strains.The antagonistic strains of Fusarium oxysporum ACCC37402 and Fusarium sporotrichioides ACCC36464,which were the the pathogen fungi of garlic root rot,were screened.The preliminary identification and functional identification of the selected strains were carried out.The effect of multifunctional bacterial suspension on the growth of garlic seedlings and the effect of disease resistance were studied by pot experiment in greenhouse.Strain 37402-1 had good antagonistic effects against ACCC37402 and ACCC36464,with antibacterial rate of 52.70%and 37.98%.Bacillus siamensis was identified as a strain based on the sequence homology of 16S rDNA.The results of other functional studies showed that Bacillus siamensis 37402-1 had the ability to hydrolyze protein,produce iron carrier and dissolve organophosphate and inorganic phosphorus.Pot experiments in greenhouse showed that Bacillus siamensis 37402-1 suspension inoculated could promote the growth of garlic seedlings.Field experiments showed that Bacillus siamensis 37402-1 inoculated with it increased garlic yield by 12.78%and changed soil enzyme activities(increasing soil sucrase and urease activity,and reducing soil catalase activity).Bacillus siamensis 37402-1 has multiple functional characteristics,and has good antagonistic effects against garlic root rot.At the same time,Bacillus siamensis 37402-1 can significantly promote the growth of garlic seedlings and improve the yield of garlic under field conditions.It is expected to be developed as an efficient microbial fertilizer production strain.