College of Biosystems Engineering and Food Science, Ningbo Research Institute, Zhejiang University, Zhejiang, 315100, China.
Key Laboratory of Agro-Products Postharvest Handling of Ministry of Agriculture and Rural Affairs, Zhejiang Key Laboratory for Agro-Food Processing, National-Local Joint Engineering Laboratory of Intelligent Food Technology and Equipment, Zhejiang, 310058, China.
New Phytol. 2021 Jul;231(1):432-446. doi: 10.1111/nph.17378. Epub 2021 Apr 29.
Investigation into plant-fungal pathogen interactions is one of the most interesting fields in plant sciences. However, the roles of plant volatile organic compounds in the arms race are still largely unknown. Based on precise quantification of plant volatiles, we discovered that the plant volatile organic compound (E)-2-hexenal, at concentrations that were similar to or lower than those in tissues of strawberry and tomato fruits, upregulates sulfate assimilation in spores and hyphae of the phytopathogenic fungus Botrytis cinerea. This upregulation is independent of the types of sulfur sources in the plant and can be achieved in the presence of inorganic sulfate and organic sulfur sources. Using the fungal deletion mutants, we further found that sulfate assimilation is involved in the infection of tomato and strawberry fruits by B. cinerea, and that the severity of the disease is proportional to the sulfate content in the fruits. Both before and during the infection, (E)-2-hexenal induced utilisation of plant sulfate by B. cinerea facilitates its pathogenesis through enhancing its tolerance to oxidative stress. This work provides novel insights into the role of plant volatiles in plant-fungal pathogen interaction and highlights the importance of sulfur levels in the host in the prevention of grey mould disease.
植物与真菌病原体相互作用的研究是植物科学中最有趣的领域之一。然而，植物挥发性有机化合物在这场军备竞赛中的作用在很大程度上仍然未知。基于对植物挥发物的精确定量，我们发现植物挥发性有机化合物（E）-2-己烯醛在浓度上与草莓和番茄果实组织中的浓度相似或更低，可上调植物病原菌 Botrytis cinerea 的孢子和菌丝中硫酸盐的同化。这种上调独立于植物中的硫源类型，并且可以在存在无机硫酸盐和有机硫源的情况下实现。使用真菌缺失突变体，我们进一步发现硫酸盐同化参与了 B. cinerea 对番茄和草莓果实的感染，并且疾病的严重程度与果实中的硫酸盐含量成正比。在感染之前和期间，（E）-2-己烯醛通过诱导 B. cinerea 利用植物中的硫酸盐，促进其对氧化应激的耐受性，从而促进其发病机制。这项工作为植物挥发物在植物-真菌病原体相互作用中的作用提供了新的见解，并强调了宿主中硫水平在预防灰霉病中的重要性。
