干旱胁迫下不同甘蔗品种叶片抗氧化酶活性和渗透调节物质含量的变化

我国80%以上的甘蔗种植在旱地,干旱缺水是影响甘蔗生产的主要因子。研究不同甘蔗品种的抗旱生理生化特性对于抗旱甘蔗品种选育和抗旱栽培技术研发具有重要意义。本研究采用桶栽方式,对抗旱性有差异的F172(抗旱性强)和YL6(不抗旱)2个甘蔗品种在苗期及伸长期分别进行不同程度的干旱胁迫及复水处理,探讨了不同甘蔗品种抗旱性与叶片抗氧化酶活性和渗透调节物质含量的关系。结果表明:抗旱性较强的甘蔗品种F172在干旱胁迫条件下叶片中氧自由基清除酶系中的超氧化物歧化酶(SOD)、过氧化物酶(POD)和抗氧化保护酶过氧化氢酶(CAT)活性及非可溶性蛋白(ISP)、可溶性糖(SS)含量显著提高;与不抗旱甘蔗品种YL6相比,甘蔗品种F172叶片中丙二醛(MDA)、非可溶性糖(ISS)含量相对比较稳定;而不抗旱甘蔗品种YL6在干旱胁迫条件下叶片中氧自由基清除酶反应较迟钝,MDA和ISS含量上升幅度相对较大,而可溶性蛋白(SP)、ISP含量下降。说明甘蔗叶片抗氧化酶活性和渗透调节物质含量的差异是品种耐干旱胁迫存在差异的生理基础。 

Changes of Antioxidant Enzyme Activities and Contents of Osmotic Regulation Substances in Leaves of Different Sugarcane Varieties under#br# Drought Stress#br#

Over 80% of sugarcane is grown in poor upland field in China, and drought stress has become an important factor limiting the sugarcane production. Investigating the physiological mechanisms of sugarcane drought resistance is important to breed new drought resistant sugarcane varieties and develop drought resistant farming technologies. In the present study, pot culture was used to grow two sugarcane varieties, drought resistant F172 and drought sensitive YL6, and different drought stress and re-watering treatments were applied at seedling and elongating stages, respectively. The relationships between the drought resistance and the activities of antioxidant enzymes and the contents of osmotic substances in different sugarcane varieties were investigated. The results showed that the activity of oxygen radical scavenging enzyme system including superoxide dismutase (SOD) and peroxidase, the activity of antioxidant protective  enzyme catalase (CAT), and the contents of insoluble protein (ISP), soluble sugar (SS) in the leaves of the drought resistant variety F172 were significantly increased under drought stress, and the contents of malondialdehyde (MDA) and insoluble sugar (ISS) were relatively stable compared with the drought sensitive variety YL6. The oxygen radical scavenging enzyme system in the drought sensitive variety YL6 was lagged in response to drought stress with significant increases in MAD and ISS and decreases in SP and ISP in leaves. It indicates that the differences in the activities of antioxidant enzymes and the contents of osmotic regulation substances in the leaves are the physiological foundation of the difference in resistance of sugarcane varieties to drought stress.