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作 者 ：魏学玲;史如霞;贾凌云;刘艳;张辉;姜羽;杨颖丽*

期 刊 ：植物研究 2011年 31卷 1期 页码：34-39

关键词：Pb2+胁迫；种子萌发；叶绿素；抗氧化酶；小麦；

Keywords:Pb2+ stress, seed germination, chlorophyll, soluble protein, wheat,

摘 要 ：

利用室内水培实验，研究了外源一氧化氮（NO）供体硝普钠（SNP）对Pb²⁺处理下小麦（Triticum aestivum L.）种子萌发、幼苗生长及相关生理指标变化的影响。结果表明，Pb²⁺处理使小麦种子发芽势、发芽率、幼苗根长和茎长均显著降低，诱导叶绿素a、叶绿素b含量减少及叶绿素荧光参数F_v/F_m和F_v/F_o的比值减小，25 μmol·L^-1 SNP明显缓解Pb²⁺胁迫对种子萌发及幼苗生长的抑制作用，提高Pb²⁺胁迫下叶绿素a、叶绿素b含量及F_v/F_m和F_v/F_o的比值，而100 μmol·L^-1SNP无明显缓解作用。此外，25和100 μmol·L^-1SNP诱导Pb²⁺胁迫下小麦幼苗叶片过氧化氢酶（CAT）活性增强和可溶性蛋白含量增多，但100 μmol·L^-1SNP处理降低了过氧化物酶（POD）活性。结果说明，外源NO促进Pb²⁺胁迫下小麦种子萌发及幼苗生长，提高叶绿素和可溶性蛋白含量，诱导CAT活性升高，从而增强小麦对Pb²⁺胁迫的适应性。

Abstract:By the method of solution culture, wheat was used to investigate the effects of exogenous NO donor SNP on seed germination and seedlings physiological characteristics under Pb²⁺ stress. The results showed that Pb²⁺ treatment resulted in significant decreases in seed germination and seedling growth of wheat，and notable reduction in the levels of chlorophyll a, chlorophyll b and chlorophyll fluorescence, 25 μmol·L^-1 SNP could alleviate the inhibition of Pb²⁺ on these indexes. No significant changes in the activities of CAT and POD were observed in comparison with the control under Pb²⁺ stress. However, the application of SNP induced increases of CAT activity and soluble protein content in wheat seedlings under Pb²⁺ treatment. Therefore, exogenous NO could alleviate the poison of Pb²⁺ and enhance the adaptation of wheat seedlings to Pb²⁺ stress.

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