探究哥斯达黎加链霉菌A-m1对小麦赤霉病的防治作用，以期为小麦绿色生产提供技术支撑。通过培养分析菌株A-m1，以‘扬麦30’为供试小麦品种，在信阳市甘岸镇（东经114°04′，北纬32°19′）开展田间试验，采用数据单因素方差分析和样本间差异显著性分析，测定A-m1对小麦赤霉病病菌分生孢子萌发和菌丝生长的抑制活性，解析菌株A-m1抑菌作用的遗传和生理基础，研究在扬花期喷撒A-m1菌液和播种期施用A-m1固体菌肥对小麦赤霉病的防治作用。结果表明，小麦赤霉病菌分生孢子的萌发能够完全被菌株A-m1发酵液抑制，菌丝的生长也受到干扰和抑制。A-m1基因组编码有链霉素和四环素抗生素合成基因，还编码有酪蛋白酶、β-1,3-葡聚糖酶、纤维素酶、几丁质酶等基因，具有抑制或分解病原菌的作用，生化分析进一步验证了这些酶类的分泌。在小麦扬花期喷洒A-m1发酵液，对小麦赤霉病防效为52.28%，防治作用与80%多菌灵1000倍液相当。小麦播种期施用菌株A-m1菌肥替代部分复合肥，多酚氧化酶、过氧化物酶、过氧化氢酶和苯丙氨酸解氨酶4种防御酶活性均显著高于对照组，同时丙二醛含量更低，对小麦赤霉病防效为57.18%。研究发现，菌株A-m1对小麦赤霉病的生长有抑制作用，并解析了防治作用产生的机制，大田试验也明确了A-m1发酵液喷雾和播种期菌株A-m1菌肥施用对小麦赤霉病的防效。研究为小麦生产中化肥农药减施技术的开发应用奠定了良好基础。

The control effects of Streptomyces costaricanus strain A-m1 on wheat scab were studied in order to lay a foundation for the development of biocontrol agents for wheat production. The effects of A-m1 on spore germination and mycelial growth of wheat scab pathogen were determined, the genetic and enzymatic basis of the bacteriostatic effect of strain A-m1 was analyzed, and the control effect of spraying A-m1 bacterial liquid at flowering stage and applying A-m1 solid bacterial fertilizer at sowing stage on wheat scab was explored. The findings revealed that strain A-m1 exerted a potent inhibitory influence on both the conidial germination and mycelial expansion of Fusarium graminearum. The genomic of A-m1 encoded genes for the synthesis of streptomycin and tetracycline antibiotics, as well as genes such as casein, β-1, 3-glucanase, cellulase, and chitinase. They had the effect of inhibiting or decomposing pathogenic bacteria, and further biochemical analysis verified the secretion of the four enzymes. Spraying A-m1 fermentation broth at wheat flowering stage had a control effect of 52.28 % on wheat scab, a level of efficacy comparable to that of a 1000-fold dilution of 80% carbendazim solution. The application of A-m1 bacterial fertilizer substituting a portion of the traditional compound fertilizer at the sowing stage, led to a marked increase in the activity of defense enzymes, including polyphenol oxidase, peroxidase, catalase, and phenylalanine ammonia-lyase. At the same time, the content of malondialdehyde was lower, and the control effect on wheat scab was 57.18 %. In this study, the control effect of strain A-m1 on wheat scab was clarified, and the underlying mechanisms of its protective action had been partially dissected. Field experiments also confirmed the control effect of A-m1 fermentation broth spraying and strain A-m1 bacterial fertilizer application on wheat scab during sowing period, which laid a good foundation for the reduction of chemical fertilizers and pesticides in wheat production.