Universidade de Lisboa, Faculdade de Ciências de Lisboa, BioISI, Campo Grande, 1749-016, Lisboa, Portugal.
Research Group Plant Defense Physiology, Max Planck Institute for Chemical Ecology, 07745, Jena, Germany.
Plant Sci. 2019 Jun;283:266-277. doi: 10.1016/j.plantsci.2019.01.024. Epub 2019 Mar 12.
Hormones play an important role in fruit ripening and in response to biotic stress. Nevertheless, analyses of hormonal profiling during plant development and defense are scarce. In this work, changes in hormonal metabolism in grapevine (Vitis vinifera) were compared between a susceptible (Trincadeira) and a tolerant (Syrah) variety during grape ripening and upon infection with Botrytis cinerea. Infection of grapes with the necrotrophic pathogen Botrytis cinerea leads to significant economic losses worldwide. Peppercorn-sized fruits were infected in the field and mock-treated and infected berries were collected at green, veraison and harvest stages for hormone analysis and targeted qPCR analysis of genes involved in hormonal metabolism and signaling. Results indicate a substantial reprogramming of hormonal metabolism during grape ripening and in response to fungal attack. Syrah and Trincadeira presented differences in the metabolism of abscisic acid (ABA), indole-3-acetic acid (IAA) and jasmonates during grape ripening that may be connected to fruit quality. On the other hand, high basal levels of salicylic acid (SA), jasmonates and IAA at an early stage of ripening, together with activated SA, jasmonates and IAA signaling, likely enable a fast defense response leading to grape resistance/ tolerance towards B. cinerea. The balance among the different phytohormones seems to depend on the ripening stage and on the intra-specific genetic background and may be fundamental in providing resistance or susceptibility. In addition, this study indicated the involvement of SA and IAA in defense against necrotrophic pathogens and gains insights into possible strategies for conventional breeding and/or gene editing aiming at improving grape quality and grape resistance against Botrytis cinerea.
激素在果实成熟和应对生物胁迫中起着重要作用。然而，植物发育和防御过程中激素谱分析仍然很少。在这项工作中，比较了易感染品种（Trincadeira）和耐感染品种（Syrah）葡萄在成熟过程中和感染灰葡萄孢（Botrytis cinerea）后的激素代谢变化。感染葡萄的坏死性病原菌灰葡萄孢会导致全球范围内的重大经济损失。在田间用胡椒粒大小的果实进行感染，并进行模拟处理，在绿熟期、转色期和收获期采集感染和未感染的浆果，进行激素分析和参与激素代谢和信号转导的基因的靶向 qPCR 分析。结果表明，在葡萄成熟和应对真菌攻击过程中，激素代谢发生了实质性的重编程。在葡萄成熟过程中，Syrah 和 Trincadeira 的脱落酸（ABA）、吲哚-3-乙酸（IAA）和茉莉酸代谢存在差异，这可能与果实品质有关。另一方面，在成熟早期，SA、茉莉酸和 IAA 的基础水平较高，同时激活了 SA、茉莉酸和 IAA 信号通路，这可能使葡萄对 B. cinerea 具有快速的防御反应，从而导致其具有抗性/耐受性。不同植物激素之间的平衡似乎取决于成熟阶段和种内遗传背景，并可能是提供抗性或易感性的基础。此外，本研究表明 SA 和 IAA 参与了对坏死性病原菌的防御，并深入了解了常规育种和/或基因编辑的可能策略，旨在提高葡萄的品质和对灰葡萄孢的抗性。
