Table_1_Biocontrol ability of Bacillus velezensis T9 against Apiospora arundinis causing Apiospora mold on sugarcane.DOCX

Sugarcane (Saccharum officinarum L.) may be infected with Apiospora, which can produce the toxin 3-nitropropionic acid (3-NPA) during improper transportation and storage. The consumption of sugarcane that contains 3-NPA can lead to food poisoning. Therefore, this study sought to explore a novel biocontrol agent to prevent and control Apiospora mold. Bacteria were isolated from the soil of healthy sugarcane and identified as Bacillus velezensis T9 through colony morphological, physiological and biochemical characterization and molecular identification. The inhibitory effect of B. velezensis T9 on Apiospora mold on sugarcane was analyzed. Assays of the cell suspension of strain T9 and its cell-free supernatant showed that T9 had significant in vitro antifungal activities against Apiospora arundinis and thus, would be a likely antagonist. Scanning electron microscopy and transmission electron microscopy showed that treatment with T9 significantly distorted the A. arundinis mycelia, perforated the membrane, contracted the vesicles, and decomposed most organelles into irregular fragments. A re-isolation experiment demonstrates the ability of T9 to colonize the sugarcane stems and survive in them. This strain can produce volatile organic compounds (VOCs) that are remarkably strong inhibitors, and it can also form biofilms. Additionally, the cell-free supernatant significantly reduced the ability of A. arundinis to produce 3-NPA and completely inhibited its production at 10%. Therefore, strain T9 is effective at controlling A. arundinis and has the potential for further development as a fungal prevention agent for agricultural products.

甘蔗（Saccharum officinarum L.）可能感染Apiospora，该病原体在运输和储存不当的情况下，可产生3-硝基丙酸（3-NPA）毒素。含有3-NPA的甘蔗消费可能导致食物中毒。因此，本研究旨在探索一种新型的生物控制剂，以预防和控制Apiospora霉。从健康甘蔗土壤中分离出的细菌经菌落形态学、生理生化特征及分子鉴定，被确认为Bacillus velezensis T9。对B. velezensis T9对甘蔗上Apiospora霉的抑制作用进行了分析。T9菌株的细胞悬浮液及其无细胞上清液的实验表明，T9在体外对Apiospora arundinis具有显著的抗真菌活性，因此有可能成为潜在的拮抗剂。扫描电子显微镜和透射电子显微镜观察显示，T9处理显著扭曲了A. arundinis菌丝，穿孔菌膜，收缩液泡，并将大多数细胞器分解为不规则碎片。重新分离实验证明了T9在甘蔗茎中定殖和存活的特性。该菌株能产生挥发性有机化合物（VOCs），这些化合物具有显著的抑菌作用，并且能形成生物膜。此外，无细胞上清液显著降低了A. arundinis产生3-NPA的能力，并在10%浓度下完全抑制其产生。因此，T9菌株在控制A. arundinis方面表现出显著效果，并具有作为农产品真菌预防剂的进一步开发潜力。