Although it is well known that parasitic weeds such as Orobanche (broomrape) significantly reduce the yield of economically important crops, their infection-induced oxidative changes need more exploration in their host plants. Moreover, applying an eco-friendly approach to minimize the infection is not yet available. This study was conducted to understand the effect of Orobanche ramosa infection on oxidative and redox status of tomato plants and the impact of hormonal (indole acetic acid (IAA); 0.09 mM and salicylic acid (SA); 1.0 mM) seed-priming upon mitigating the infection threats. Although Orobanche invades tomato roots, its inhibitory effects on shoot biomass were also indicted. Orobanche infection usually induces oxidative damage i.e., high lipid peroxidation, lipoxygenase activity and H2O2 levels, particularly for roots. Interestingly, hormonal seed-priming significantly enhanced tomato shoots and roots growth under both healthy and infected conditions. Also, IAA and SA treatment significantly reduced Orobanche infection-induced oxidative damage. The protective effect of seed-priming was explained by increasing the antioxidant defense markers including the antioxidant metabolites (i.e., total antioxidant capacity, carotenoids, phenolics, flavonoids, ASC, GSH, tocopherols) and enzymes (CAT, POX, GPX, SOD, GR, APX, MDHAR, DHAR), particularly in infected tomato seedlings. Additionally, cluster analysis indicated the differential impact of IAA- and SA-seed-priming, whereas lower oxidative damage and higher antioxidant enzymes' activities in tomato root were particularly reported for IAA treatment. The principal component analysis (PCA) also proclaimed an organ specificity depending on their response to Orobanche infection. Collectively, here and for the first time, we shed the light on the potential of seed-priming with either IAA or SA to mitigate the adverse effect of O. ramosa stress in tomato plants, especially at oxidative stress levels.

中文翻译：

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荷尔蒙种子引发提高了番茄对扫帚菜感染的抵抗力

尽管众所周知，寄生杂草如 Orobanche (broomrape) 会显着降低具有重要经济价值的作物的产量，但它们感染引起的氧化变化需要对寄主植物进行更多的探索。此外，目前尚无法采用环保方法来最大限度地减少感染。本研究旨在了解 Orobanche ramosa 感染对番茄植株氧化和氧化还原状态的影响以及荷尔蒙（吲哚乙酸 (IAA)；0.09 mM 和水杨酸 (SA)；1.0 mM）种子引发对减轻影响的影响感染威胁。虽然 Orobanche 侵入番茄根部，但它对地上部生物量的抑制作用也被指出。Orobanche 感染通常会引起氧化损伤，即高脂质过氧化、脂肪氧化酶活性和 H2O2 水平，特别是对于根。有趣的是，在健康和感染条件下，荷尔蒙种子引发显着促进了番茄芽和根的生长。此外，IAA 和 SA 处理显着减少了 Orobanche 感染引起的氧化损伤。种子引发的保护作用可以通过增加抗氧化防御标记来解释，包括抗氧化代谢物（即总抗氧化能力、类胡萝卜素、酚类、黄酮类、ASC、GSH、生育酚）和酶（CAT、POX、GPX、SOD、GR , APX, MDHAR, DHAR)，特别是在受感染的番茄幼苗中。此外，聚类分析表明 IAA 和 SA 种子引发的不同影响，而 IAA 处理特别报告了番茄根中较低的氧化损伤和较高的抗氧化酶活性。主成分分析 (PCA) 还宣布器官特异性取决于它们对 Orobanche 感染的反应。总的来说，在这里也是第一次，我们揭示了用 IAA 或 SA 进行种子引发的潜力，以减轻 O. ramosa 胁迫对番茄植物的不利影响，尤其是在氧化胁迫水平。