两种微生物与蓝莓根腐病菌在根表的竞争性关系研究

Research on the competitive relationship between two microorganisms and the blueberry root rot pathogen on rhizoplane

为研制针对蓝莓根腐病的生防菌剂,从三叶草根表分离出一株具有生防作用的真菌,采用形态学和分子生物学的方法对该真菌进行鉴定,将其与阿氏芽孢杆菌R-B-01(Bacillus aryabhattai)、禾谷镰刀菌R-F-02(Fusarium graminearum)接入蓝莓组培苗根系,观察根系变化与菌株定殖情况,并结合体视显微镜和电子显微镜探究3种微生物在蓝莓根表的相互作用。结果表明,形态学和分子生物学鉴定该真菌为棘孢木霉(Trichoderma asperellum),命名为R-F-01。阿氏芽孢杆菌R-B-01和棘孢木霉R-F-01在根表对禾谷镰刀菌R-F-02有明显的抑制作用,阻止了禾谷镰刀菌R-F-02对蓝莓根系的侵害;显微镜观察发现3种微生物均有刺激根系分枝的作用,其中以棘孢木霉R-F-01效果最强;棘孢木霉R-F-01以空间竞争的方式抑制禾谷镰刀菌R-F-02。首次揭示阿氏芽孢杆菌R-B-01和棘孢木霉R-F-01通过空间竞争的机制在蓝莓根表发挥生防作用,为蓝莓根腐病生防菌剂的研发提供了新的思路。

In order to develop a biocontrol agent against root rot of blueberry,a fungus with biological control effect isolated from the rhizoplane of clover,and was identified by morphology and molecular biology methods.The fungi R-F-01,Bacillus aryabhattai R-B-01 and Fusarium graminearum R-F-02 were mixed into blueberry sterile tissue culture seedlings roots,then the changes of roots and colonization of strains were observed.Stereomicroscope and electron microscope were used to research the interaction of the three microorganisms on the rhizoplane.The results showed that morphological and molecular biology identified the fungus as Trichoderma asperellum,named R-F-01.Bacillus aryabhattai R-B-01 and Trichoderma asperellum R-F-01 have a significant inhibitory effect on Fusarium graminearum R-F-02 on the rhizoplane,and prevented the erosion and poisoning of the roots caused by Fusarium graminearum R-F-02.Microscopic observation found that three microorganisms can stimulate root branching,and Trichoderma asperellum R-F-01 has the strongest effect among them.Trichoderma asperellum R-F-01 inhibits Fusarium graminearum R-F-02 in a way of space competition.It was found for the first time that Bacillus aryabhattai R-B-01 and Trichoderma asperellum R-F-01 have biocontrol effect on blueberry rhizoplane through a mechanism of space competition.This study provided a new idea for the development of blueberry root rot biocontrol agents.