玉米茎腐病生防菌株的筛选及抑菌作用研究

以吉林省玉米茎腐病优势菌株禾谷镰孢菌（Fusarium graminearum）为供试菌，从土壤中分离筛选生防菌株，获得对禾谷镰孢菌具有显著抑制作用的细菌菌株GsAl-2，抑菌率为46.27%。经分子生物学鉴定及系统发育分析，确定其为Asaia lannensis。通过抑菌机制研究表明，GsAl-2可显著抑制禾谷镰孢菌生长，使菌丝细胞膜渗透性增强、内含物外溢、菌丝脂质过氧化程度提高。GsAl-2与玉米膜下滴灌水肥药一体化技术联用试验表明，GsAl-2对玉米茎腐病的田间防效为58.68%±1.78%，GsAl-2的施用并未增加玉米表观病害。探讨A.lannensis的生防作用，为其在农业病害防治方面的应用提供基础信息。

Screening of Biocontrol Strains against Corn Stalk Rot and Antifungal Mechanisms

Fusarium graminearum, the dominant pathogen of corn stalk rot in Jilin province, was used as an indicator to isolate and screen a bacterial strain Gs-2, which showed a significant inhibitory effect on F. graminearum. This strain was identified as Asaia lannensis by morphological observation, molecular biological identification and phylogenetic analysis. The inhibition rate of A. lannensis on F. graminearum was 46.27%. Research on the antifungal mechanism showed that A. lannensis can lead to growth inhibition, irregular thickness, and overflow of contents, increase in hypha cell membrane permeability and peroxidation of F. graminearum hyphae. The combined experiment of A. lannensis and drip irrigation under mulch showed that the field control effect of A. lannensis against corn stalk rot was 58.68% ±1.78%, and the application of A. lannensis did not increase the apparent disease of corn. The biological control effect of A. lannensis was examined for the first time, which laid a foundation for its application in agricultural disease control.