Abstract: Heat-shock pretreatment at 42℃ for 4 h and recovery at 26 .5℃ for 4 hgreatly improved greatly survival percentage of maize seedlings under high temperature stress . Heat-shock pretreatment and recovery at 26. 5℃ for 4 h significantly enhanced the activities of antioxidant enzymes CAT, SOD, GR and APX and the levels of antioxidants ASA and GSH in maize seedlings . The seedlings with heat-shock retained higher activities of antioxidant enzymes and higher levels of antioxidants than that without heat-shock during heat stress and recovery , indicating that the increase of activities of antioxidant
enzymes and levels of antioxidants is the physiological basis for the formation of heat tolerance induced by heat-shock in maize seedlings .

Key words: Maize ( Zea mays) seedlings

摘要： 玉米幼苗经过42℃热激4 h 并恢复4 h 后, 显著提高了玉米幼苗在高温处理下的存活率。热激并恢复4 h 后, 不同程度地提高了抗氧化酶系统过氧化氢酶(CAT) , 超氧化物歧化酶(SOD) , 谷胱甘肽还原酶(GR) , 抗坏血酸过氧化物酶(APX) 和过氧化物酶(GPX) 的活性以及抗氧化剂还原型抗坏血酸(ASA)和谷胱甘肽(GSH) 的含量, 且经过热激的玉米幼苗在高温处理期间及其后的恢复过程中均能保持相对较高的抗氧化酶活性和抗氧化剂水平, 说明保持较高的抗氧化酶活性和抗氧化剂水平是热激诱导的玉米幼苗耐热性形成的生理基础之一。

关键词: 玉米幼苗, 热激, 耐热性, 抗氧化酶, 抗氧化剂FONT