Liu Haixu, Zhang Zhuoqun, Xu Ying, Zhao Yifan, An Tai, Du Xiuming, Wen Jingzhi
College of Plant Protection, Northeast Agricultural University, Harbin, China.
Pest Manag Sci. 2025 Apr;81(4):2191-2201. doi: 10.1002/ps.8619. Epub 2024 Dec 22.
Phytophthora sojae (Kaufmann and Gerdemann), a pathogenic oomycete, causes one of the most destructive soybean diseases, Phytophthora root and stem rot (PRR). Previous studies have shown that benzoxazines (BXs) such as 6-methoxy-benzoxazolin-2-one (MBOA) and benzoxazoline-2-one (BOA) in maize root exudates inhibit the chemotaxis of zoospores, as well as the mycelial growth and pathogenicity of P. sojae. However, the molecular mechanism by which BXs regulate the growth, development and pathogenicity of P. sojae is still not well understood at present.
By analyzing the transcriptome data, it was determined that PsPTGES2 (encoding prostaglandin E synthase 2), PsGST1 (encoding glutathione S transferase), and PsEPHX2 (encoding soluble epoxide hydrolase) in the arachidonic acid (AA) pathway were involved in the response of P. sojae to MBOA and BOA. Polyethylene glycol (PEG)-mediated protoplast transformation was performed to construct silenced transformants of PsPTGES2, PsGST1, and PsEPHX2. Our data demonstrated that PsPTGES2, PsGST1, and PsEPHX2 were involved in mycelial growth, oospore formation, zoospore encystment, cyst germination in P. sojae. PsPTGES2 and PsGST1 were involved in the pathogenicity. The silencing transformants PsPTGES2 and PsGST1 reduced the metabolic ability to AA and the resistance to BOA. Moreover, the zoospores of the silencing transformants PsPTGES2, PsGST1, and PsEPHX2 decreased the chemotaxis to genistein and repellency to BOA.
AA metabolism is involved in the growth, development and pathogenicity of P. sojae and the detoxification and recognition of P. sojae to BXs. The study results provide a solid theoretical basis for developing effective strategies to control the infection and pathogenicity of P. sojae. © 2024 Society of Chemical Industry.
大豆疫霉（考夫曼和格德曼）是一种致病性卵菌，可引发最具破坏性的大豆病害之一——疫霉根腐病（PRR）。先前的研究表明，玉米根分泌物中的苯并恶嗪（BXs），如6-甲氧基-苯并恶唑啉-2-酮（MBOA）和苯并恶唑啉-2-酮（BOA），可抑制游动孢子的趋化性，以及大豆疫霉的菌丝生长和致病性。然而，目前BXs调节大豆疫霉生长、发育和致病性的分子机制仍不清楚。
通过分析转录组数据，确定花生四烯酸（AA）途径中的PsPTGES2（编码前列腺素E合酶2）、PsGST1（编码谷胱甘肽S转移酶）和PsEPHX2（编码可溶性环氧化物水解酶）参与了大豆疫霉对MBOA和BOA的反应。采用聚乙二醇（PEG）介导的原生质体转化构建了PsPTGES2、PsGST1和PsEPHX2的沉默转化体。我们的数据表明，PsPTGES2、PsGST1和PsEPHX2参与了大豆疫霉的菌丝生长、卵孢子形成、游动孢子包囊形成、孢囊萌发。PsPTGES2和PsGST1参与了致病性。沉默转化体PsPTGES2和PsGST1降低了对AA的代谢能力以及对BOA的抗性。此外，沉默转化体PsPTGES2、PsGST1和PsEPHX2的游动孢子对染料木黄酮的趋化性降低，对BOA的排斥性增强。
AA代谢参与了大豆疫霉的生长、发育和致病性以及大豆疫霉对BXs的解毒和识别。研究结果为制定控制大豆疫霉感染和致病性的有效策略提供了坚实的理论基础。©2024化学工业协会。
