【摘要】 以春小麦新品种"陇春27号(27号)"和"陇春30号(30号)"为研究材料,分析过氧化氢酶(CAT)和二苯基氯化碘盐(DPI)对NaCl胁迫下小麦叶片渗透性调节和抗氧化反应的影响.结果表明,盐诱导两种小麦叶中w(脯氨酸)、ρ(可溶性糖)、w(可溶性蛋白)和c(丙二醛)均增加, CAT的加入减少了盐诱导的27号ρ(可溶性糖)及30号w(脯氨酸)和w(可溶性蛋白)的积累, DPI提高了两种小麦w(脯氨酸)、ρ(可溶性糖)和c(丙二醛),降低了w(可溶性蛋白).盐处理导致小麦27号c(O2·-)、w(H2O2)、超氧化物歧化酶(SOD)和抗坏血酸过氧化物酶(APX)活性均降低,使c (·OH)及过氧化物酶(POD)活性增高;小麦30号c(O2·-)、c (·OH)及APX活性增高, CAT和POD活性减弱.与单独盐处理相比,外源CAT使盐处理下两种小麦w(H2O2)降低,谷胱甘肽还原酶(GR)活性及27号APX和30号CAT活性增强; NaCl+DPI处理导致两种小麦w(H2O2)及27号APX活性降低,两种小麦c(O2·-)及POD和GR活性均增高, 30号小麦SOD与APX活性变化与27号相反.表明盐胁迫提高了两种小麦叶中渗透性调节物w(脯氨酸)、ρ(可溶性糖)和w(可溶性蛋白),导致不同的抗氧化反应,可能与胞间H2O2及质膜烟酰胺腺嘌呤二核苷酸磷酸(NADPH)氧化酶O2·-的产生有关,因为胞间H2O2的清除和NADPH氧化酶活性的抑制改变了盐诱导两种小麦的渗透性调节和抗氧化反应,且二者的效应不同.更多还原

【Abstract】 New spring wheat（Triticum aestivum cv. Longchun 27 and Longchun 30） seedlings were used to investigate the effects of exogenous catalase（CAT） and diphenylene iodonium（DPI） on osmotic adjustment substances and antioxidation responses in the leaves of wheat seedlings under salt stress and the results showed that w（proline）, ρ（soluble sugar）, w（soluble protein） and c（malondialdehyde） were elevated in the leaves of two wheat seedlings exposed to 100 mmol/L NaCl. The presence of CAT blocked the accumulation of ρ（soluble sugar） in Longchun 27 and the increases of w（proline） and w（soluble protein）in Longchun 30 under 100 mmol/L NaCl treatment. The addition of DPI further elevated the amount of w（proline）, ρ（soluble sugar） and c（malondialdehyde）, but lowered the w（soluble protein） in the leaves of two wheat seedlings treated by NaCl. Salt stress resulted in decreases of c（superoxide anion（O2·-））and w（H₂O₂） as well as superoxide dismutase（SOD） and ascorbate peroxidase（APX） activities, but in an elevation of c（·OH） level and peroxidase（POD） activity in Longchun 27 leaves. c（O2·-） and c（·OH）, as well as the activity of APX rose while CAT and POD activities decreased, when Longchun 30 seedlings were stressed with salinity. Compared with salt stress alone, NaCl + CAT treatment reduced the w（H₂O₂）but stimulated glutathione reductase（GR） in the leaves of two wheat seedlings together with APX in Longchun 27 and CAT in Longchun 30. NaCl+DPI led to a decrease of w（H₂O₂） but an increase of c（O₂·^-） generation as well as POD and GR activities in the leaves of Longchun 27 and Longchun 30. Taken together, salinity stress increased w（proline）, ρ（soluble sugar） and w（soluble protein）, and resulted in different antioxidation responses in the leaves of the two wheat seedlings, which might be associated with the production of apoplastic H₂O₂ and NADPH oxidase-dependent O₂·^-, because the elimination of apoplastic H₂O₂ and the inhibition of NADPH oxidase altered the salinity-induced osmotic adjustment and antioxidation responses, and their effects were different.更多还原