盐胁迫下内源ROS与NO的产生及其对小麦幼苗生理特性的影响  

NaCI-induced production of endogenous reactive oxygen species and nitric oxide and their effect on the physiological characteristics in wheat seedlings

作　　者：李琼[1] 高晓霞[1] 杨颖丽[1] 殷金梅[1] 吕丽荣[1] Li Qiong, Gao Xiao-xia, Yang Ying-li, Yin Jin-mei, Lu Li-rong(College of Life Sciences, Northwest Normal University, Lanzhou 730070, Chin)

机构地区：[1]西北师范大学生命科学学院,兰州730070

出　　处：《兰州大学学报（自然科学版）》2018年第2期192-199,共8页Journal of Lanzhou University(Natural Sciences)

基　　金：国家自然科学基金项目(31470464;31360094)

摘　　要：以小麦新品种陇春27为试材,研究施用过氧化氢酶(CAT、H_2O_2清除剂)、DPI(质膜NADPH氧化酶抑制剂)或PTIO(NO清除剂)对100 mmol/L NaCl处理下小麦幼苗生长、抗氧化反应以及渗透性调节的影响.结果显示:NaCl处理抑制小麦幼苗根、茎的生长,诱导根中活性氧(ROS)和NO的积累.CAT、DPI、PTIO的加入更显著地抑制盐胁迫下小麦幼苗根茎的生长,且DPI的效应最明显.这3种药品能够缓解NaCl诱导的超氧阴离子(·O_2^-)和NO的积累,但DPI或PTIO使NaCl处理的根中H_2O_2含量进一步增加,而CAT或DPI使羟自由基(·OH)含量减少.盐胁迫导致幼苗根中超氧化物歧化酶(SOD)和过氧化氢酶活性减弱,而过氧化物酶(POD)活性无显著变化.CAT的加入能缓解NaCl对CAT活性的抑制作用;DPI的加入减缓了盐对SOD、CAT的抑制效应,使POD活性降低;PTIO显著地增加了盐处理根中POD活性.盐处理导致小麦幼苗根中脯氨酸质量分数、可溶性糖质量浓度、可溶性蛋白和丙二醛(MDA)质量分数均增加.DPI导致盐处理根中脯氨酸质量分数、可溶性糖质量浓度均增加.CAT不影响NaCl对根的氧化损伤,DPI的加入导致盐处理小麦根MDA质量分数增加为对照的184%,而PTIO能够缓解盐诱导的氧化损伤.盐处理抑制小麦幼苗根茎的生长,诱导的内源性ROS和NO的产生相互影响,特别是二者共同作用调控幼苗根的生长和抗氧化反应.New spring wheat seedlings of Longchun 27（Triticum aestivum L.） were used to investigate the changes of growth, antioxidative response and osmotic adjustment in response to 100 mmol/L NaCl treatment with or without catalase（CAT）, diphenylene iodonium（DPI） or 2-phenyl-4,4, 5,5-tetramethylimid azoline-3-oxide-1-oxyl（PTIO）. The results showed that NaCl inhibited the growth of roots and shoots, resulting in the increases of reactive oxygen species（ROS） and nitric oxide（NO） content in roots.The addition of CAT, DPI or PTIO further reduced the lengths of roots and shoots in NaCl-treated seedlings, with the strongest inhibition having caused by DPI treatment. These three agents blocked the accumulation of superoxide anion（·O2^-） and NO induced by NaCl. In contrast, the content of H2 O2 further rose in NaCl＋DPI-or NaCl＋PTIO-treated roots, but the hydroxyl radical（·OH） level lowered in response to NaCl＋CAT and NaCl＋DPI treatments. The activities of superoxide dismutase（SOD） and CAT decreased in salinity-stressed roots, while peroxidase（POD） activity had on obvious change. NaCl-inhibitory effect on CAT activity was alleviated by the addition of CAT, and salinity-induced inhibition on SOD and CAT activities was removed by the addition of DPI, which reduced the activity of POD. The activity of POD significantly increased in salt-treated roots in the presence of PTIO. NaCl-treated roots exhibited a significant increase of proline, soluble sugar, soluble protein and MDA levels. The amount of proline and soluble sugar further rose in response to NaCl stress together with DPI. CAT did not affect salt-induced oxidative damage, and MDA content rose by 184% of control values in salinity-treated roots in the presence of DPI, but PTIO partly alleviated the oxidative damage induced by salt. NaCl treament inhibited the growth of roots and shoots, salinity-induced generation of endogenous NO and ROS influenced each other, their interactive roles were associated with the regulation of roo

关 键 词：盐胁迫 一氧化氮 活性氧 抗氧化酶 渗透性调节物 小麦 

分 类 号：Q945[生物学—植物学]