Zhejiang University, College of Biosystems Engineering and Food Science, Key Laboratory of Agro-Products Postharvest Handling Ministry of Agriculture, Hangzhou, 310058, People's Republic of China; Agriculture and Agri-Food Canada, Saint-Jean-sur-Richelieu Research and Development Centre,430 Boulevard Gouin, Saint-Jean-sur-Richelieu, Quebec, J3 B 3E6, Canada.
Zhejiang University, College of Biosystems Engineering and Food Science, Key Laboratory of Agro-Products Postharvest Handling Ministry of Agriculture, Hangzhou, 310058, People's Republic of China.
J Plant Physiol. 2017 Nov;218:265-274. doi: 10.1016/j.jplph.2017.09.002. Epub 2017 Sep 8.
Recent studies have highlighted the biological and physiological effects of pre-harvest ultraviolet (UV)-C treatment on growing plants. However, little is known about the involvement of volatile organic compounds (VOCs) and their response to this treatment. In this study, strawberry plants were exposed to three different doses of UV-C radiation for seven weeks (a low dose: 9.6kJm; a medium dose: 15kJm; and a high-dose: 29.4kJm). Changes in VOC profiles were investigated and an attempt was made to identify factors that may be involved in the regulation of these alterations. Principle compounds analysis revealed that VOC profiles of UV-C treated samples were significantly altered with 26 VOCs being the major contributors to segregation. Among them, 18 fatty acid-derived VOCs accumulated in plants that received high and medium dose of UV-C treatments with higher lipoxygenase and alcohol dehydrogenase activities. In treated samples, the activity of the antioxidant enzymes catalase and peroxidase was inhibited, resulting in a reduced antioxidant capacity and higher lipid peroxidation. Simultaneously, jasmonic acid level was 74% higher in the high-dose group while abscisic acid content was more than 12% lower in both the medium and high-dose UV-C treated samples. These results indicated that pre-harvest UV-C treatment stimulated the biosynthesis of fatty acid-derived VOCs in strawberry leaf tissue by upregulating the activity of enzymes of the LOX biosynthetic pathway and downregulating antioxidant enzyme activities. It is further suggested that the mechanisms underlying fatty acid-derived VOCs biosynthesis in UV-C treated strawberry leaves are associated with UV-C-induced changes in phytohormone profiles.
最近的研究强调了收获前紫外线(UV)-C 处理对生长中植物的生物和生理影响。然而,对于挥发性有机化合物(VOCs)的参与及其对这种处理的反应知之甚少。在这项研究中,草莓植株暴露在三种不同剂量的 UV-C 辐射下七周(低剂量:9.6kJm;中剂量:15kJm;高剂量:29.4kJm)。研究了 VOC 谱的变化,并试图确定可能参与调节这些变化的因素。主要化合物分析表明,UV-C 处理样品的 VOC 谱发生了显著变化,有 26 种 VOC 是分离的主要贡献者。其中,18 种脂肪酸衍生的 VOC 在接受高剂量和中剂量 UV-C 处理的植物中积累,其脂氧合酶和醇脱氢酶活性较高。在处理过的样品中,抗氧化酶过氧化氢酶和过氧化物酶的活性受到抑制,导致抗氧化能力降低和脂质过氧化增加。同时,高剂量组中的茉莉酸水平升高了 74%,而中剂量和高剂量 UV-C 处理组中的脱落酸含量分别降低了 12%以上。这些结果表明,收获前 UV-C 处理通过上调 LOX 生物合成途径中酶的活性和下调抗氧化酶活性,刺激草莓叶片组织中脂肪酸衍生 VOC 的生物合成。进一步表明,UV-C 处理草莓叶片中脂肪酸衍生 VOC 生物合成的机制与 UV-C 诱导的植物激素谱变化有关。
Plant Physiol Biochem. 2016-11