State Key Laboratory of Crop Stress Biology for Arid Areas, College of Horticulture, Northwest A & F University, Yangling 712100, Shaanxi, China.
Molecules. 2017 Sep 13;22(9):1542. doi: 10.3390/molecules22091542.
Since melatonin was identified in plants decades ago, much attention has been devoted to discovering its role in plant science. There is still a great deal to learn about the functional importance of melatonin, as well as its functional mode. In this paper, we examine the role of melatonin treatment in the response of Rehd. to alkaline conditions. Stressed seedlings showed chlorosis and suppressed growth. However, this phenotype was ameliorated when 5 µM melatonin was added to the irrigation solution. This supplementation was also associated with a reduction in cell membrane damage and maintenance of a normal root system architecture. Fewer reactive oxygen species (ROS) were accumulated due to the enhanced scavenging activity of antioxidant enzymes superoxide dismutase, peroxidase, and catalase. In addition, alkaline-stressed seedlings that received the melatonin supplement accumulated more polyamines compared with untreated seedlings. Transcript levels of six genes involved in polyamine synthesis, including , -, and -, and , -, and -, -, were upregulated in response to melatonin application. All of these results demonstrate that melatonin has a positive function in plant tolerance to alkaline stress because it regulates enzyme activity and the biosynthesis of polyamines.
自从几十年前在植物中发现褪黑素以来，人们一直致力于发现它在植物科学中的作用。关于褪黑素的功能重要性及其功能模式，还有很多需要了解。在本文中，我们研究了褪黑素处理在 Rehd. 对碱性条件的反应中的作用。受胁迫的幼苗表现出黄化和生长抑制。然而，当将 5 µM 褪黑素添加到灌溉溶液中时，这种表型得到了改善。这种补充还与细胞膜损伤减少和正常根系结构的维持有关。由于抗氧化酶超氧化物歧化酶、过氧化物酶和过氧化氢酶的清除活性增强，积累的活性氧 (ROS) 减少。此外，接受褪黑素补充的碱性胁迫幼苗与未处理的幼苗相比积累了更多的多胺。褪黑素处理后，参与多胺合成的六个基因（包括 、 、 和 、 、和 、 、和 、 、和 ）的转录水平上调。所有这些结果表明，褪黑素在植物耐受碱性胁迫方面具有积极作用，因为它调节酶活性和多胺的生物合成。
