油菜种子发芽过程中依赖于抗坏血酸的H_2O_2清除酶活性的变化

Changes of activities of ascorbate dependent H 2O 2 scavenging enzymes during imbibition and germination of oil rape seeds.

用在黑暗中培养７２ｈ的油菜种子，研究其吸胀和发芽过程中依赖于抗坏血酸Ｈ２Ｏ２清除途径的酶和过氧化氢酶的活性变化．实验表明，油菜干种子抗坏血酸过氧化物酶活性很低，种子在吸胀过程中，活性缓慢增加，萌发后活性很快增加．单脱氢抗坏血酸还原酶活性在种子萌发以后增加很快，而脱氢抗坏血酸还原酶除了在种子萌发后短时间内增加以外，活性变化不大．谷胱甘肽还原酶活性在种子萌发以后明显增加．过氧化氢酶的活性在种子萌发前开始增加，萌发后增加较快．每粒种子的抗坏血酸含量萌发后增加明显，而单位鲜重的抗坏血酸含量变化不大．

During imbibition and germination of oil rape seed in the dark over 72 h, activities of ascorbate dependant H 2O 2 scavenging enzymes and catalase were determined. The results showed that the activities of ascorbate peroxidase, monodehydroascorbate reductase, glutathione reductase and catalase increased considerably in germinating seeds, especially during radicle emergence ( between 24～48 h ). The activity of dehydroascorbate reductase did not greatly increase. During the germination the ascorbate content per seed increased largely, and the ascorbate content per unit fresh weight did not change. The dehydroascorbate content per unit fresh weight decreased.