中文摘要：

为了分离筛选对小麦赤霉病菌有拮抗作用的细菌，并研究其拮抗特性。采用系列稀释法和平板对峙法从土壤中分离筛选小麦赤霉病菌拮抗菌；采用16SrDNA序列分析和生理生化特性进行拮抗菌的鉴定；采用平板对峙法研究拮抗菌的拮抗谱；通过田间喷施试验研究拮抗菌对小麦赤霉病的防治效果。结果显示：从土壤中分离筛选到小麦赤霉病菌拮抗菌AF0907，根据其形态、生理生化特性以及16SrDNA序列分析，菌株AF0907被鉴定为枯草芽孢杆菌（Bacillus subtilis）。AF0907对10种常见的植物病原菌都具有拮抗效果；菌株AF0907可以抑制禾谷镰刀菌菌丝的生长，也能抑制病原菌孢子的萌发。田间试验结果显示：拮抗菌AF0907可以有效地降低小麦赤霉病的发病率，先喷施拮抗菌液再喷施赤霉孢子液处理下防治效率可以达到40．37％。

英文摘要：

To isolate and screen antifungal bacteria against Fusarium graminearum, and to study the antagonistic characteristics of the bacteria, serial dilution and confrontation culture were conducted on wheat rhizospheric soil. Antifungal strain was then identified according to the morphological, physiological, biochemical characteristics and 16S rDNA gene sequencing, and the phylogenetic tree of the antltungaI bacteria was constructed by MEGAS. 0. The antagonistic activities of the bacteria against other plant pathogens were detected by confrontation culture, and the field effect of antagonistic bacteria against wheat scab was investigated by spraying the antagonistic bacteria on wheat during heading stage. Strain AF0907 with strong inhibitory activity against F. graminearum was isolated from soil, and was identified as Bacillus subtilis. AF0907 showed antagonistic activities against other ten plant pathogens besides F. graminearum, and could inhibit the hyphal growth and spore germination of F. graminearum. Field experiments revealed that AF0907 effectively reduced the incidence of wheat scab, and the disease control efficiency could reach up to 40.37% under the condition of spraying solution of antifungal bacteria followed by spores of F. graminearum.