抗氧化系统参与循环干旱锻炼提高烟草植株抗旱性的形成  

Involvement of Antioxidant Defense System in Enhancement of Drought Resistance in Tobacco (Nicotiana tabacum L.) Plants through Circular DroughtHardening

作　　者：荣智媛[1] 张晓海[2] 杨双龙[1] 徐照丽[2] 李军营[2] 黄国宾[1] 赵静[1] 龚明[1] 

机构地区：[1]云南师范大学生命科学学院 生物能源持续开发利用教育部工程研究中心 云南省生物质能与环境生物技术重点实验室,昆明650500 [2]云南省烟草农业科学研究院,云南玉溪653100

出　　处：《植物生理学报》2012年第7期705-713,共9页Plant Physiology Journal

基　　金：国家自然科学基金(30460016);中国烟草总公司云南省公司科技计划项目(2010YN10)

摘　　要：对漂浮育苗的烟草幼苗进行控水-半萎焉-复水-恢复的循环干旱锻炼。结果表明,这种干旱锻炼能显著提高烟草叶片抗氧化剂谷胱甘肽(GSH)、抗坏血酸(AsA)的含量、还原型抗氧化剂在总抗氧化剂中的比例和抗氧化酶包括超氧化物歧化酶(SOD)、抗坏血酸过氧化物酶(APX)、过氧化氢酶(CAT)、愈创木酚过氧化物酶(GPX)、谷胱甘肽还原酶(GR)的活性,降低丙二醛(MDA)的含量。当烟草植株遭受后续的干旱胁迫时,与未锻炼的对照相比,干旱锻炼过的烟草植株能保持较高的GSH和AsA含量、还原型抗氧化剂在总抗氧化剂中的比例和抗氧化酶(SOD、APX、CAT、GPX和GR)活性,以及较低的MDA含量,表明这种循环干旱锻炼提高了细胞抗氧化能力,有助于缓解烟草植株由干旱引起的氧化胁迫及其所导致的伤害,最终提高其抗旱性。这些结果表明,抗氧化系统参与了循环干旱锻炼提高烟草植株抗旱性的形成过程。Circular drought-hardening was applied on tobacco seedlings raised on floating trays by the circle of water control-half wilting-rehydration-recovery. The results showed that the circular drought-hardening can significantly increased contents of the antioxidant glutathione （GSH） and ascorbic acid （AsA）, the ratio of reduced to total antioxidants and activities of the antioxidant enzymes including superoxide dismutase （SOD）, ascorbate peroxidase （APX）, catalase （CAT）, guaiacol peroxidase （GPX）, glutathione reductase （GR）, and decreased the content of malondialdehyde （MDA）. When the circular drought-hardened seedlings were subjected to following drought stress, as compared with control without the drought-hardening, they could retain higher contents of GSH and AsA, ratio of reduced to total antioxidants and activities of the antioxidant enzymes （SOD, APX, CAT, GPX, GR）, and lower content of MDA. All these results indicated that the circular drought-hardening enhanced intracellular anti-oxidative capacity in tobacco plants, which will be helpful to alleviate drought-induced oxidative stress and subsequent damage, and finally to increase drought resistance, and antioxidant defense system took part in the drought hardening-induced enhancement of drought resistance in tobacco plants.

关 键 词：烟草 循环干旱锻炼 抗氧化系统 干旱胁迫 抗旱性 

分 类 号：S572[农业科学—烟草工业]