外源甲基乙二醛对干旱胁迫下板栗幼苗的影响

甲基乙二醛(MG)是一种在植物中具有多种功能的新型信号分子.为探究MG对板栗幼苗干旱胁迫的影响,以两年生'黄棚'板栗幼苗为试材,通过聚乙二醇(PEG)模拟干旱胁迫并进行MG及其清除剂N-乙酰半胱氨酸(NAC)处理,分析板栗幼苗叶片超氧化物歧化酶(SOD)、过氧化物酶(POD)、过氧化氢酶(CAT)、抗坏血酸过氧化物酶(...

Effects of exogenous methylglyoxal on chesnut seedlings under drought stress

Methylglyoxal(MG)is a novel signaling molecule with multiple functions in plants.To explore the effects of MG on Chinese chestnut(Castanea mollissima)under drought stress,two-year-old‘Huangpeng’chestnut seedlings were treated with 15%polyethylene glycol(PEG)coupled with MG or its scavenger N-acetyl-L-cys-teine(NAC).We measured the activities of antioxidant enzymes,including superoxide dismutase(SOD),peroxidase(POD),catalase(CAT),ascorbate peroxidase(APX)and glutathione reductase(GR),and glyoxalase enzymes,including glyoxalaseⅠ(GlyⅠ)and glyoxalaseⅡ(GlyⅡ).Contents of antioxidants such as endogenous MG,malondialdehyde(MDA),H₂O₂,and O₂^-·as well as the osmotic adjustment substances including proline(Pro),soluble sugar(SS),glycine betaine(GB)were also detected.The results showed that 0.5 mmol·L^-1MG significantly increased the activities of antioxidant enzymes(SOD,POD,CAT,APX,GR)and glyoxalase enzymes(GlyⅠ,GlyⅡ)in leaves of chestnut seedlings under drought stress,elevated the contents of osmotic adjustment substances(Pro,SS,GB)and antioxidant substances(ASA,GSH),and reduced the contents of MG,MDA,H₂O₂,O₂^-·and dehydroascorbate(DHA).Drought stress induced damages such as membrane lipid peroxidation and osmotic stress was alleviated by MG,leading to an overall improved adaptability of chestnut to drought stress.Moreover,the addition of MG scavenger NAC could reverse the effects induced by MG,indicating that MG had positive impacts on drought resistance of chestnut plants.Our study provided a theoretical basis for further exploring the mechanism of MG in alleviating drought stress induced symptoms in chestnut.