We isolated a new Trichoderma harzianum strain, named T-A66. Potato dextrose agar (PDA) was the best medium for both mycelium growth and sporulation of T-A66 strain, while sucrose and potassium nitrate were the best source of carbon and nitrate, respectively. T-A66 strain and its culture filtrate significantly antagonized the growth of the pathogen Fusarium oxysporum in in vitro tests. An experiment using potted plants showed that the T-A66 strain promoted growth and induced disease resistance of bitter gourd seedlings to bitter gourd wilt caused by F. oxysporum, by inducing quick H2 O2 burst and callose deposition, as well as increasing antioxidant enzymes activities and phenolic compounds content. Indole acetic acid (IAA) was involved in the beneficial effects of T-A66. Ultimately, T-A66 strain diminished membrane lipid peroxidation and cell death, and controlled successfully bitter gourd wilt in greenhouse with a biocontrol efficiency of 90.32% after 15 days of F. oxysporum inoculation. The results suggested a good biocontrol potential of T-A66 strain against bitter gourd wilt.

中文翻译：

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哈茨木霉T-A66对尖孢镰刀菌引起的苦瓜枯萎病的生物学特性及生防机制

我们分离了一个新的哈茨木霉菌株，命名为 T-A66。马铃薯葡萄糖琼脂（PDA）是 T-A66 菌株菌丝体生长和孢子形成的最佳培养基，而蔗糖和硝酸钾分别是碳和硝酸盐的最佳来源。在体外试验中，T-A66菌株及其培养滤液显着拮抗尖孢镰刀菌的生长。盆栽试验表明，T-A66菌株通过诱导快速H2O2爆裂和胼胝质沉积，以及增加抗氧化酶活性和抗氧化酶活性，促进苦瓜幼苗对尖孢镰刀菌引起的苦瓜枯萎病的抗病性和抗病性。酚类化合物含量。吲哚乙酸 (IAA) 参与了 T-A66 的有益作用。最终，T-A66菌株减少了膜脂过氧化和细胞死亡，并在接种尖孢镰刀菌15天后成功控制了温室苦瓜枯萎病，生防效率为90.32%。结果表明T-A66菌株对苦瓜枯萎病具有良好的生防潜力。