Hg^(2+)与POD复合处理对小麦萌发及幼苗生长的影响  

Effects of POD and Hg^(2+) on Seed Germination andSeedling Growth of Wheat

作　　者：马剑敏[1] 李今[2] 张改娜[1] 杨柯金[1] 王琳[1] 吴振斌[2] 

机构地区：[1]中国科学院水生生物研究所,武汉430072 [2]河南师范大学生命科学学院,新乡453002

出　　处：《植物学通报》2004年第5期531-538,共8页Chinese Bulletin of Botany

摘　　要：通过水培实验研究了0、10、20、50、70和100 mg.L-1 Hg2+和65 U.mL-1的过氧化物酶(POD)混合浸种对小麦(Triticum aestivum L.)萌发及幼苗生长过程中的10个形态和生理生化指标的影响。结果表明:施加外源POD可明显提高种子发芽率、植株日均增重和幼苗叶片的可溶性蛋白含量,增加幼苗叶片内源超氧物歧化酶(SOD)和POD的活性,拮抗Hg2+胁迫对种子发芽率、苗高、日均增重及叶片可溶性蛋白含量的不利影响,Hg2+浓度较高时(≥50 mg.L-1),对种子发芽率和日均增重的拮抗作用更明显,并对较低浓度Hg2+(≤20 mg.L-1)胁迫引起的叶片SOD活性的上升和低于100 mg.L-1的 Hg2+胁迫引起的叶片POD活性的上升有进一步的促进作用;然而对幼苗平均最长根长度、侧根数和幼苗叶片叶绿素含量则无明显影响。Experiments were carried out to study the effects of soaking wheat seeds with POD(peroxidase) and Hg2+ together on 10 morphological and physiological indexes during the seedgermination and seedling growth. The results showed that exogenous POD could raise the seedgermination rate, wake the increased average weight per day and the soluble protein centent of theleaves, and enhance the activities of SOD (superoxide dismutase) and POD of the leaves. The exog-enous POD also resist and weaken the effects of the Hg2+ stress on the seeds germination rate, heightof wheat, increased average weight per day and the soluble protein. Moreover, when Hg2+≥50 mg.L-1, the resisting and weakening effects on the germination rate and the increased average freshweight per day were more obvious. Besides, exogenous POD could further heighten the activities ofSOD under the stress of Hg2+≤20 mg.L-1, and POD under the stress Hg2+≤100 mg.L-1 in the leaves.But exogenous POD should not obviously affect on the average length of the longest wheat roots,the number of lateral roots and the chlorophyll content of the leaves.

关 键 词：小麦 萌发 幼苗 生长 浸种 过氧化物酶 HG 

分 类 号：S512.1[农业科学—作物学]