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

作　　者：王芳[1] 于璐 齐泽铮 周长军 于吉东 WANG Fang;YU Lu;QI Ze-zheng;ZHOU Chang-jun;YU Ji-dong(College of Life Sciences and Agroforestry,Heilongjiang Provincial Key Laboratory of Resistance Gene Engineering and Protection of Biodiversity in Cold Areas,Qiqihar University,Qiqihar 161006;Soybean Molecular Breeding Faculty Daqing Branch,Heilongjiang Academy of Agricultural Science,Daqing 163319)

机构地区：[1]齐齐哈尔大学生命科学与农林学院抗性基因工程与寒地生物多样性保护黑龙江省重点实验室,齐齐哈尔161006 [2]黑龙江省农科院大庆分院大豆分子育种学部,大庆163319

出　　处：《生物技术通报》2024年第7期216-225,共10页Biotechnology Bulletin

基　　金：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)。

摘　　要：【目的】镰刀菌根腐病是世界范围内大豆生产上最具破坏性的土传病害之一,为获得对禾谷镰刀菌Fusarium graminearum具有较好拮抗效果的生防菌株。【方法】从健康大豆根际土壤分离细菌,平板对峙法筛选拮抗菌株,通过形态观察、生理生化特性、胞外酶活性及促生特性对菌株进行鉴定分析,采用盆栽试验进一步测定菌株生防及促生效果。【结果】筛选出的4株芽孢杆菌和1株假单胞杆菌对F.graminearum的抑菌率均达到60%以上,对F.oxysporum,F.solani,F.longifundum以及F.equiseti也均有一定的抑制作用,其发酵液及挥发代谢物均会影响F.graminearum的生长。5株拮抗菌具有产蛋白酶、纤维素酶以及葡聚糖酶的活性,解磷、解钾、固氮以及产铁载体的能力。综合以上测试结果,菌株20-8具有较强的抑菌及大豆促生效果。根据形态特征及16S rRNA序列分析,将菌株20-8鉴定为暹罗芽孢杆菌(Bacillus siamensis)。该菌株的发酵上清液可以破坏F.graminearum菌丝体结构,无细胞发酵上清液可以显著抑制孢子萌发。室内盆栽防效测定结果表明,20-8的稀释发酵液对F.graminearum引起大豆根腐病的防效可达46.08%,并且促进大豆植株生长。【结论】筛选鉴定的暹罗芽孢杆菌20-8具有解磷、解钾、固氮以及产铁载体及多种胞外酶功能,其稀释发酵液具有较强的抗真菌活性及大豆促生能力,菌株20-8可以用于防治F.graminearum引起的大豆根腐病。【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 stro

关 键 词：大豆根腐病 拮抗细菌 分离鉴定 生物防治 

分 类 号：S435.651[农业科学—农业昆虫与害虫防治] S476[农业科学—植物保护]