百合花瓣抗氧化酶系统对干旱胁迫响应的研究

Studies on the Response of Lily Petal Antioxidant Enzyme System to Drought Stress

以‘诺宾’(Robina)、‘索蚌’(Sorbonne)、‘西伯利亚’(Siberia)3个云南产量较大的观赏百合品种切花为试验材料,研究了干旱胁迫对花瓣相对含水量、可溶性蛋白和丙二醛含量、抗氧化酶活性和抗氧化酶相关基因表达量的影响,并采用隶属函数法对其抗旱性进行了综合评价。结果表明:随着干旱胁迫增强,花瓣相对含水量和可溶性蛋白含量下降,而代表膜质过氧化程度的丙二醛(MDA)含量持续上升。干旱胁迫下花瓣的超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、过氧化物酶(POD)、谷胱甘肽还原酶(GR)、抗坏血酸过氧化物酶(APX)活性在处理的前期、中期持续上升,后期下降,说明前中期有较高的活性氧(ROS)清除能力,之后抗氧化能力下降;抗氧化酶基因Cu-ZnSOD、MnSOD、CAT、APX和GR的表达先升后降,而Fe-SOD的表达一直下降,POD则一直保持升高的趋势。根据隶属函数平均值大小百合品种抗旱性由强到弱为:‘索蚌’>‘诺宾’>‘西伯利亚’。

This study selected three varieties of lily,‘Robina’,‘Sorbonne’and‘Siberia’as materials,to determine the effects of drought stress on their relative water,soluble protein,malondialdehyde content,antioxidant enzyme activity and expression of antioxidant enzyme related genes.Drought resistance was evaluated comprehensively by membership function method.Results showed that relative water content and soluble protein content of petals decreased with the increase of drought stress,while the content of malondialdehyde(MDA),which represents the degree of membrane peroxidation,continued to rise until the end of drought stress.Under drought stress,activities of superoxide dismutase(SOD),catalase(CAT),peroxidase(POD),glutathione reductase(GR)and ascorbic acid peroxidase(APX)of petals continued to rise in the early and middle stages of treatment,but declined in the later stage,showed that petal cells had higher ROS scavenging capacity at early and middle stages,and then antioxidant capacity decreased.Expression of Cu-ZnSOD,MnSOD,CAT,APX and GR increased first and then decreased,while the expression of Fe-SOD decreased all the time,and the POD kept increasing.According to the average value of membership function,drought resistance of these three lily varieties ranked from strong to weak was Sorbonne>Nobina>Siberia.