期刊
ACTA PHYSIOLOGIAE PLANTARUM
卷 33, 期 1, 页码 173-180出版社
SPRINGER HEIDELBERG
DOI: 10.1007/s11738-010-0535-5
关键词
Apple leaves; Drought stress; Ascorbate-glutathione cycle; ROS
资金
- Natural Science Fund of Shannxi province
- Northwest AF University
- Guizhou province Academy of Agricultural Sciences [[2009]024]
To explore the significance of the ascorbate-glutathione cycle under drought stress, the leaves of 2-year-old potted apple (Malus domestica Borkh.) plants were used to investigate the changes of each component of the ascorbate-glutathione cycle as well as the gene expression of dehydroascorbate reductase (DHAR, EC 1.8.5.1), ascorbate peroxidase (APX, EC 1.11.1.11) and glutathione reductase (GR, EC 1.6.4.2) under drought stress. The results showed that the malondialdehyde (MDA) and H2O2 concentrations in apple leaves increased during drought stress and began to decrease after re-watering. The contents of total ascorbate, reduced ascorbic acid (AsA), total glutathione and glutathione (GSH) were obviously upregulated in apple leaves when the soil water content was 40-45%. With further increase of the drought level, the contents of the antioxidants and especially redox state of AsA and GSH declined. However, levels of them increased again after re-watering. Moreover, drought stress induced significant increase of the activities of enzymes such as APX, scavenging H2O2, and also of monodehydroascorbate reductase (MDHAR, EC 1.6.5.4), DHAR and GR used to regenerate AsA and GSH, especially when the soil water content was above 40-45%. During severe drought stress, activities of the enzymes were decreased and after re-watering increased again. Gene expression of cytoplasmic DHAR, cytoplasmic APX and cytoplasmic GR showed similar changes as the enzyme activities, respectively. The results suggest that the ascorbate-glutathione cycle is up-regulated in response to drought stress, but cannot be regulated at severe drought stress conditions.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据