生物技术通报2024，Vol.40Issue(7)：216-225,10.DOI:10.13560/j.cnki.biotech.bull.1985.2024-0070
大豆镰刀菌根腐病拮抗菌的筛选及生防效果
Screening and Biocontrol Effect of Antagonistic Bacteria against Soybean Root Rot
摘要
Abstract
[Objective]Fusarium root rot is one of the most devastating soil-borne diseases in soybean planting areas worldwide.This study aims to obtain antagonistic bacteria effectively against Fusarium graminearum.[Method]Antagonistic strains were isolated from the rhizosphere soil of healthy soybean plants and screened by plate confrontation method.The morphological characteristics,physiological and biochemical properties,extracellular enzyme activity and growth-promoting characteristics of strains were identified and evaluated.The biocontrol and growth promotion effect of the strain was determined by pot experiment.[Result]Four Bacillus strains and 1 Pseudomonas strain screened were effective against F.graminearum,with the inhibition rates above 60%.Besides,the strains also had certain inhibitory effect on F.oxysporum,F.solani,F.longifundum and F.equiseti.The fermentation liquid and volatile metabolites of the strains affected the growth of F.graminearum.And all strains demonstrated proteolytic,cellulolytic and glucanolytic activity,and were able to solve phosphorus and potassium,as well as possessed nitrogen fixation and iron carrier.Based on the above test results,strain 20-8 had stronger antifungal effect and soybean growth-promoting effect,and it was identified as Bacillus siamensis based on morphology characteristics and 16S rRNA sequencing.The fermentation supernatant of the strain destroyed the mycelium structure of F.graminearum,and the cell-free fermentation supernatant significantly inhibited the spore germination.Moreover,the diluted fermentation solution of the strain enhanced the resistance of soybean to F.graminearum,with biocontrol efficiency of 46.08%,and promoted the growth of soybean seedling.[Conclusion]These results indicated that the screeded and identified B.siamensis 20-8 possesses the ability of solving phosphorus solubilization and potassium,fixing nitrogen and producing iron carrier as well as a variety function of extracellular enzymes.Its diluted fermentation solution has strong antifungal activity and soybean growth promotion ability.Therefore,strain 20-8 may be used as a biocontrol strain against soybean root rot caused by F.graminearum.关键词
大豆根腐病/拮抗细菌/分离鉴定/生物防治Key words
soybean root rot/antagonistic bacteria/isolation and identification/biological control引用本文复制引用
王芳,于璐,齐泽铮,周长军,于吉东..大豆镰刀菌根腐病拮抗菌的筛选及生防效果[J].生物技术通报,2024,40(7):216-225,10.基金项目
国家自然科学基金项目(31801725),黑龙江省省属本科高校基本科研业务费科研项目(145309327) （31801725）
