黄瓜幼苗对热胁迫的生理反应及叶绿素荧光特性

研究高温对黄瓜生长的影响,筛选简单可靠的耐热性鉴定指标,对于提高耐热育种效率具有重要意义.将5个黄瓜自交系分别在38℃和42℃热胁迫下处理3d,测定了处理前后黄瓜幼苗的生理指标及叶绿素荧光参数的变化,结果表明:热害指数较高的自交系,其细胞膜透性也较大；随着热胁迫温度的升高,超氧化物歧化酶(SOD)、抗坏血酸过氧化物酶(...

Physiological Reaction and Chlorophyll Fluorescence Characteristics of Cucumber Seedlings under Hot Stress

Investigating the effects of high temperature on cucumber growth and sorting simple and reliable identification indexes of hot resistance have important roles in improving hot-resistant breeding efficiency.Physiological indexes and chlorophyll fluorescence parameters of 5 cucumber inbred lines treated at 38 ℃ and 42 ℃ hot stress conditions were determined.The results showed that the inbred lines with higher hot injury index have higher membrane permeability.As hot stress increase,SOD,APX activities and MDA levels elevates,but POD,CAT activities and soluble protein decreases The photochemical maximum efficiency of PSⅡ（Fv/Fm）,actual photochemical yield（Yield）,and actual photochemical efficiency of PSⅡ（ФPSⅡ）increase with hot stress rising.Electron transport rate（ETR）rise rapidly at 38 ℃ and decreased quickly at 42 ℃.There is an extremely significant correlation between electric conductivity percentage and hot injury index.The changes of SOD,APX,soluble protein content and ETR had significant correlation with hot injury index,too.The electric conductivity percentage,yield and ETR change could be reliable indexes for identifying hot resistance of cucumber seedlings according to simplicity and operability.