Isophorone (3,5,5‐trimethylcyclohex‐2‐en‐1‐one) is a plant‐derived volatile compound with strong phytotoxic activity. Here, we aimed to elucidate the mechanism of action of isophorone, and to this end, the effects of isophorone on shoot fresh weight, chlorophyll content, electrolyte leakage, and lipid peroxidation of Lactuca sativa L. and photosynthetic electron transport activity in chloroplast isolated from Spinacia oleracea L. were investigated. Isophorone induced light‐independent decreases in shoot fresh weight and light‐dependent chlorosis. In addition, increased electrolyte leakage and lipid peroxidation occurred under light conditions. However, the inhibitory activity on photosynthetic electron transport was unexpectedly low, and electrolyte leakage and lipid peroxidation were induced even under dark conditions. These results suggest that the inhibition of photosynthetic electron transport is not the main mechanism of action of isophorone and that the phytotoxic effects are mainly due to light‐independent oxidative damage and subsequent loss of cell membrane integrity.

中文翻译：

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异佛尔酮诱导的非光依赖性脂质过氧化和细胞膜完整性丧失

异佛尔酮（3,5,5-三甲基环己基-2-烯-1-酮）是一种植物来源的挥发性化合物，具有很强的植物毒性活性。在这里，我们旨在阐明异佛尔酮的作用机理，并为此目的，研究异佛尔酮对紫花苜蓿芽苗鲜重，叶绿素含量，电解质渗漏和脂质过氧化以及光合电子转运活性的影响。菠菜对L.进行了调查。异佛尔酮引起的枝条鲜重和光依赖的萎黄病的光不依赖性降低。另外，在光照条件下发生的电解质泄漏和脂质过氧化增加。然而，对光合电子传输的抑制活性出乎意料地低，甚至在黑暗条件下也引起电解质泄漏和脂质过氧化。这些结果表明，光合作用电子传递的抑制不是异佛尔酮的主要作用机理，而植物毒性作用主要是由于光不依赖的氧化损伤和随后细胞膜完整性的丧失。