褪黑素预处理对多年生黑麦草抗旱性的影响
The effects of melatonin pretreatment on drought tolerance of perennial ryegrass (Lolium perenne)

以多年生黑麦草盆栽植株为材料,采用干旱胁迫前3 d预处理的方法,研究了0、25、50、75、100 μmol/L褪黑素溶液对多年生黑麦草抗旱性的影响,并分析了其可能的生理机制。结果表明,25、50、75 μmol/L的褪黑素溶液预处理,具有提高多年生黑麦草抗旱性的作用,这可能与褪黑素处理后,叶片相对含水量增加,电解质外渗减少,Fv/Fm值下降速率以及叶绿素和类胡萝卜素分解速率减缓有关;而100 μmol/L褪黑素溶液预处理则降低了多年生黑麦草的抗旱性。研究结果对于提高多年生黑麦草的抗旱性,以及褪黑素在植物上的应用,具有一定的指导意义。
In this study,0,5,50,5 and 100 μmol/L melatonin were applied to pot plants of perennial ryegrass 3 days prior to drought stress,and the effects of melatonin on drought tolerance and related physiological mechanism were analyzed.Results showed that melatonin pretreatment at the 25,0 and 75 μmol/L improved drought tolerance of perennial ryegrass.These findings are indicated by the higher relative water content,lower electrolyte leakage,higher photochemical efficiency,and slower decomposition rates of chlorophyll and carotenoid pigments.Pretreatment with 100 μmol/L melatonin decreased drought tolerance of perennial ryegrass.The improvement of drought tolerance of perennial ryegrass and the application of melatonin in plants will benefit from the findings in this research.