| In recent years,soil-borne diseases such as potato black scurf and fusarium wilt have become more and more serious,which has greatly affected the quality and output of potatoes and caused huge economic losses.In order to find the antagonistic strains of the two pathogens,the soils in different habitats in Wuchuan and Hushi were collected and screened according to the method of screening for spore bacteria.96 strains of pure cultured strains were obtained after coating,streaking,and separation.The antagonistic strains against Rhizoctonia solani and Fusarium oxysporum were screened by the method of plate-assisted larvae,calculate the inhibitory rate.Based on the 16 S rDNA sequence,preliminary classification and identification were performed by NCBI database comparison.Eight strains of Bacillus subtilis strains,two strains of Bacillus alginolyticus,two strains of Bacillus thuringiensis,three strains of Bacillus amyloliquefaciens,two strains of Bacillus subtilis,two strains of Bacillus subtilis,and three strains of Bacillus subtilis were obtained.One strain of Bacillus cervisis,2 strains of Bacillus subtilis,1 strain of Bacillus cereus,1 strain of Achromobacter xylosoxidans and 1 strain of Lysobacter.The antagonistic effects of strains A17,A30,M06,M13,C08,M04,C06,and Z01 were better.In potato tubers tested,strains of M06 and C08 bacteria rotted the potato tuber,The antagonism effect of strain M13 against the black scurf is weak,and the antagonism of the bacillus of the other strains is consistent with the results of the plate countermeasures.At the same time,the growth-promoting ability of the antagonistic strains(fixed nitrogen,phosphorus,iron-producing carrier,and ability to produce plant hormone IAA)are identified.Both C08 and A02 have nitrogen fixation,all strains of antagonistic strains have the ability to dissolve inorganic phosphorus,strains Z01,A30 have strong ability to produce IAA.Strains M04,C03 have strong iron-producing carriers.The strains of the siblings Bacillus siamensis,Bacillus menthol,Bacillus amyloliquefaciens,and Bacillus subtilis have the prospect of being excellent biocontrol bacteria,and there is no mutual antagonism among these strains,and they can be further used as bacterial agents,they can applied to the actual. |
