Fungal endophytes produce many secondary metabolites that can reduce root rot diseases. Soybean is a particularly important crop worldwide. Endophytic fungi can be isolated, identified, and incorporated into sustainable agriculture for the biological control of many diseases. The aim of this study was to isolate some endophytic fungi for controlling the most important diseases of soybean plants and to study the mechanisms underlying this biocontrol regarding the suppression of pathogens. Ten endophytic fungi were isolated from soybean plants. Among them, the 3 fungi isolates that exhibited a high percentage of antagonistic activity against Rhizoctonia solani, the causal pathogen of root rot disease of soybean plants, were identified as Trichoderma longibrachiatum S12, T. asperellum S11, and T. atroviride PHYTAT7. The 3 fungi isolates had the ability to produce pectinase and chitinase and to solubilize phosphors. Moreover, they produced siderophores and indole acetic acid (IAA), which have a strong effect on the growth of the plants. The 3 isolates reduced disease severity by 64, 60, and 55%, respectively than the infected control. The results suggest that certain endophytic fungi associated with soybean plants have potential for the management of root rot diseases in soybean. Moreover, these isolates can be considered as having a growth-promoting effect in soybean plants.

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与大豆植物相关的内生真菌及其对茄红枯萎病的拮抗活性

真菌内生菌产生许多次生代谢产物，可以减少根腐病。大豆是世界范围内特别重要的作物。可以分离，鉴定内生真菌，并将其掺入可持续农业中，以生物防治许多疾病。这项研究的目的是分离一些内生真菌，以控制大豆植物的最重要疾病，并研究抑制病原体的生物控制机制。从大豆植物中分离出十种内生真菌。其中，对大豆植物根腐病的致病菌即茄枯萎病菌表现出高拮抗活性的3种真菌菌株被鉴定为长木霉菌S12，曲霉T. astroellum S11和Atroviride PHYTAT7。这三种真菌分离物具有产生果胶酶和几丁质酶以及溶解磷的能力。此外，他们还产生了铁载体和吲哚乙酸（IAA），它们对植物的生长有很强的影响。与感染的对照相比，这3种分离株分别将疾病严重程度降低了64％，60％和55％。结果表明，与大豆植物相关的某些内生真菌具有处理大豆根腐病的潜力。此外，这些分离株可被认为在大豆植物中具有促进生长的作用。结果表明，与大豆植物相关的某些内生真菌具有处理大豆根腐病的潜力。此外，这些分离株可被认为在大豆植物中具有促进生长的作用。结果表明，与大豆植物相关的某些内生真菌具有处理大豆根腐病的潜力。此外，这些分离株可被认为在大豆植物中具有促进生长的作用。