中国农业科学

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亚油酸乙醇胺在番茄对灰葡萄孢诱导抗性中的作用

邵淑君,胡璋健,师恺   

  1. 浙江大学农业与生物技术学院,杭州 310058
  • 出版日期:2021-12-23 发布日期:2021-12-23

The role of Linoleyl ethanolamide in tomato defense against Botrytis cinerea

SHAO ShuJun, HU ZhangJian, SHI Kai   

  1. College of Agriculture and Biotechnology, Zhejiang University, Hangzhou 310058
  • Published:2021-12-23 Online:2021-12-23

摘要: 【背景】灰霉病是危害番茄(Solanum lycopersium)的重要病害之一,防治不及时可造成20%—40%减产。目前生产上多以化学防治为主,但存在农产品安全及环境污染的风险。N-酰基乙醇胺(NAE)为植物天然存在的脂质生物活性化合物,在哺乳动物中具有多种免疫功能,但其在植物免疫中的作用和机制尚不清楚。【目的】探讨N-酰基乙醇胺诱导番茄防御灰葡萄孢(Botrytis cinerea)的作用,为开发番茄灰霉病绿色防控产品提供依据。【方法】以番茄 ‘Moneymaker’植株为材料,研究外源施用硬脂酰乙醇胺(NAE 18:0、亚油酸乙醇胺(NAE 18:2)、廿二碳五烯酸乙醇胺(NAE 22:5)对番茄叶片光合特性的影响及对灰霉病发生的缓解作用。测定番茄叶片的荧光参数和抗病基因PIIPR1NPR1NrACO1PYR1a的表达以及茉莉酸(jasmonic acid,JA)、水杨酸(salicylic acid,SA)、乙烯(ethylene,ETH)、脱落酸(abscisic acid,ABA)、生长素(indoleacetic acid,IAA)含量。以乙烯信号转导突变体植株never ripenr)及对照植株Pearson(PB)为材料,测定亚油酸乙醇胺对番茄叶片光合特性和病原菌繁殖的影响。【结果】在体外培养过程中灰葡萄孢生长并不受外源N-酰基乙醇胺的影响,外源施用N-酰基乙醇胺能显著提高番茄植株对灰霉病的抗性,缓解由灰葡萄孢侵染导致的番茄叶片光系统II实际光化学效率(ΦPSII)下降的趋势。3种N-酰基乙醇胺中,亚油酸乙醇胺施用后番茄叶片灰霉病病情指数降至1.3,灰葡萄孢Actin的相对表达量下调60%,效果最佳。番茄植株接种灰葡萄孢后PIIPR1NPR1、NrACO1的表达有不同程度上调。外源亚油酸乙醇胺处理并接种灰葡萄孢后PIINrACO1的表达进一步增强,其中乙烯合成基因ACO1的表达显著高于PIINr的表达。番茄植株接种灰葡萄孢后叶片中水杨酸、茉莉酸、生长素和乙烯含量增加,但外源亚油酸乙醇胺处理并接种灰葡萄孢后只有ETH含量显著增加。进一步研究发现,外源亚油酸乙醇胺处理不能缓解灰葡萄孢对番茄乙烯突变体nr植株的危害。【结论】外源施用亚油酸乙醇胺能够提高番茄内源光合效率和抗病基因的表达及内源激素乙烯的含量,增强番茄植株对灰霉病的抗性,推测其诱导抗性的发生可能与乙烯信号路径相关。

关键词: 番茄, N-酰基乙醇胺(NAE), 亚油酸乙醇胺, 灰霉病, 灰葡萄孢, 乙烯

Abstract: BackgroundGray mold is one of the important diseases of tomato and causes significant yield losses up to 20%-40%. Nowadays, chemical control are often used in tomato production, which is effective but increases the risk of agricultural products safety and results in environmental pollution. N-acylethanolamines (NAEs) are a kind of lipid bioactive compounds naturally occurring in plants, which have been identified to have a variety of immune functions in mammals, however, their role in plant immunity is still unknown.ObjectiveThus, investigating the effects of NAEs on tomato plant defense against gray mold infection is undoubtedly of great significance for regulation of tomato resistance to gray mold.MethodIn this study, tomato ‘Moneymaker’ plants were infected by Botrytis cinerea with or without exogenous NAE 18:0, NAE 18:2, NAE 22:5, and then photosynthetic characteristics and the B. cinerea growth were measured. To reveal the underlying mechanism of NAE 18:2 induced plant resistance to B. cinerea, Fluorescence parameters of tomato leaves, transcript abundance of defense-related genes (e.g. PII, PR1, NPR1, Nr, ACO1, PYR1a), and contents of plant hormones (e.g. JA, SA, ETH, ABA, IAA) were measured. Furthermore, ethylene-insensitive mutant was employed to verify the function of NAE 18:2.ResultThe growth of B. cinerea was not affected by exogenous NAEs treatment during in vitro culture. The photosystem II photochemical efficiency (ΦPSII) of tomato significantly decreased under B. cinerea infection. However, exogenous NAEs treatment was able to enhance the ΦPSII, and NAE 18:2 has the best effect on tomato plant defense against B. cinerea, which reduced the disease index to 1.3 and the actin gene transcript level of B. cinerea by 60%. The expressions of PR1 and NPR1 could be induced by B. cinerea infection but not by NAE 18:2 treament. However, the expressions of PII, Nr and ACO1 were up-regulated when plants were pre-treated by NAE 18:2 before B. cinerea infection, the ACO1 was significantly higher than PII, Nr. Compared to the control, the contents of SA , JA, IAA and ETH in the leaves were increased significantly after B. cinerea infection, while only the contents of ETH were further increased when pre-treated by NAE 18:2. Moreover, exogenous NAE 18:2 pre-treatmetn could not improve the defense against B. cinerea in the ETH-insensitive mutant nr.ConclusionExogenous NAE18:2 treatment can increase leaf photosynthesis, transcript abundance of defense-related genes, and the contents of plant hormones. It can also improve the resisitance of tomato plants to B. cinerea, which may depend on the ETH signaling pathway.

Key words: tomato, N-acylethanolamines (NAE), linoleyl ethanolamide (NAE 18:2), gray mold, Botrytis cinerea, ethylene (ETH)