二氧化硫对小麦的氧化胁迫及其某些信号分子的调节  

SO_2-caused oxidative stress and modulation of some signal molecules in wheat.

作　　者：郝林[1] 张惠文[2] 徐昕[1] 陶思源[1] 于龙[1] 

机构地区：[1]沈阳师范大学生物系,沈阳110034 [2]中国科学院沈阳应用生态研究所,沈阳110016

出　　处：《应用生态学报》2005年第6期1038-1042,共5页Chinese Journal of Applied Ecology

基　　金：国家自然科学基金项目(30070129);辽宁省博士启动基金项目(023804111);沈阳师范大学实验中心主任基金资助项目(SY200406).

摘　　要：通过在密闭的培养箱中一次性通入不同体积浓度的SO2气体,研究了小麦幼苗超氧自由基O-·2含量和3种抗氧化酶活性的变化,探讨了信号分子水杨酸、乙烯和过氧化氢对SO2氧化胁迫的调节作用.结果表明,当通入10和40μl·L-1SO2时,小麦叶片中O-·2含量递增,过氧化物酶(POD)和过氧化氢酶(CAT)活性增强,但超氧化物歧化酶(SOD)活性降低.当SO2浓度达到50μl·L-1时,POD和CAT活性也开始降低,此时叶片尖端出现坏死,叶片绿色部位滋生大量真菌.用1mmol·L-1水杨酸(SA)(pH6.5)浸泡小麦干种子6h,或用10mmol·L-1H2O2浸泡幼苗,O-·2含量低于对照植株,而3种酶的活性高于对照植株,均可有效地减轻SO2的氧化胁迫.在SO2熏蒸下,乙烯显著抑制3种酶的活力,提高O-·2的形成速率.SA与乙烯同时使用时,SA几乎完全消除了乙烯的负面作用.By adding different concentration SO_2 to culture boxes,this paper studied the responses of wheat seedling's superoxide anion radical O^(-·)_2 and antioxidant enzymes to SO_2.The results showed that when the concentration of SO_2 was 10 and 40 μl·L^(-1),the O^(-·)_2 content and peroxidase (POD) and catalase(CAT) activities of wheat leaf were increased,while the activity of superoxide dismutase(SOD) was reduced.When the SO_2 concentration was 50 μl·L^(-1),the activities of POD and CAT were decreased,with the top end leaves appeared necrosis,and more fungi multiplied on green leaves.Presoaking wheat seeds with 1 mmol·L^(-1) salicylic acid (SA) for 6 h or with 10 mmol·L^(-1) H_2O_2 for 12 h could efficiently alleviate the oxidative stress caused by SO_2,with the O^(-·)_2 content decreased and the activities of test antioxidant enzymes increased.Under SO_2 fumigation,ethylene significantly inhibited the activities of test enzymes,and promoted the O^(-·)_2 production rate.When applying SA and ethylene at the same time,SA could almost completely eliminate the influences of ethylene on O^(-·)_2 production and test enzyme activities.

关 键 词：二氧化硫 小麦 水杨酸 乙烯 过氧化氢 

分 类 号：X173[环境科学与工程—环境科学]