Abstract Sclerotiniose, caused by Sclerotinia sclerotiorum (Lib.) deBary, is a destructive disease of Brassica campestris L. Injuries caused by insect pests, such as Plutella xylostella (L.), increase the occurrence of this disease. One hundred and sixty-one Bacillus thuringiensis strains from the Bacillus Genetic Stock Center were screened to identify strains that might protect B. campestris from both plant diseases and insect pests in this study. Challenge-inoculation assays showed seventeen B. thuringiensis strains effectively suppressed S. sclerotiorum growth by inducing systemic resistance in B. campestris, and six of these strains exhibited high insecticidal activity against P. xylostella. In addition, B. thuringiensis elicited a strong hypersensitive response in B. campestris leaves and triggered systemic signals that were transferred from treated roots and leaves to untreated leaves. Quantitative real-time PCR and transcriptome sequencing showed genes involved in salicylic acid, ethylene, and jasmonic acid signaling and in brassinosteroid synthesis pathways were upregulated. The phenotypic and genotypic diversity of B. thuringiensis makes it an effective biocontrol agent for simultaneously protecting B. campestris from sclerotiniose and P. xylostella.

中文翻译：

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筛选苏云金芽孢杆菌菌株以鉴定针对油菜中核盘菌和小菜蛾的新型潜在生防剂

摘要 由Sclerotinia sclerotiorum (Lib.) deBary 引起的核盘菌病是Brassica campestris L. 的一种破坏性病害。小菜蛾(Plutella xylostella (L.)) 等害虫引起的病害增加了该病害的发生。在本研究中，筛选了来自芽孢杆菌遗传储备中心的 161 株苏云金芽孢杆菌菌株，以鉴定可能保护油菜籽免受植物病虫害的菌株。挑战接种试验表明，17 个苏云金芽孢杆菌菌株通过在油菜中诱导系统抗性有效抑制了核盘菌的生长，其中 6 个菌株对小菜蛾表现出很高的杀虫活性。此外，苏云金芽孢杆菌在 B. 野油菜叶并触发系统信号，这些信号从处理过的根和叶转移到未经处理的叶子上。定量实时 PCR 和转录组测序显示，参与水杨酸、乙烯和茉莉酸信号传导以及油菜素类固醇合成途径的基因被上调。苏云金芽孢杆菌的表型和基因型多样性使其成为同时保护油菜籽免受核盘菌和小菜蛾侵害的有效生物防治剂。