小麦茎基腐病生防菌HB-081的鉴定及抑菌活性

Identification and activity of biocontrol strain HB-081 against wheat Crown Rot

为筛选用于小麦茎基腐病的生防菌,以假禾谷镰刀菌为指示菌,从女贞叶片中分离筛选到一株拮抗菌HB-081,根据形态学、生理生化特征及分子生物学对其进行鉴定,并对该菌株的抑菌活性和盆栽防效进行了测定.结果表明:菌株HB-081对假禾谷镰刀菌的抑菌率为61.86%;结合形态学、生理生化特性,16S rRNA及gyrA基因序列分析,将其鉴定为解淀粉芽孢杆菌.该菌株的无菌发酵液能够抑制病原菌的菌丝生长,导致菌丝出现分支增多、膨大畸形;无菌发酵液对病原菌的孢子萌发过程也具有抑制作用;对扣试验显示,该菌株产生的挥发性物质可以抑制病原菌的菌落生长;盆栽试验中,该菌株对小麦茎基腐病的防治效果为66.69%.此外,菌株HB-081对9种植物病原真菌具有拮抗效果.

To screen effective candidate biocontrol agents against wheat crown rot caused by Fusarium pseudograminearum,the endophytic bacteria strain HB-081,isolated from leaves of privet.The strain was identified based on morphological,physiological and biochemical characteristics,and molecular biology.The antifungal activity and control efficiency were further studied.The results indicated that the strain HB-081 presented obvious inhibitory effect against F.pseudograminearum,with the inhibition rate of 61.86%.Strain HB-081 was identified as Bacillus amyloliquefaciens based on morphological,physiological and biochemical characteristics,and sequences analysis of 16S rRNA and gyrA gene.The cell-free fermentation liquid suppressed both the mycelial growth and conidial germination of F.pseudograminearum.Strain HB-081 volatile compounds showed inhibitory effect on F.pseudograminearum.The pot experiment tests showed that the control efficiency of strain HB-081 on wheat crown rot was 66.69%.Strain HB-081 showed biological activities against nine plant pathogenic fungi.