铬胁迫下不同品种玉米种子和幼苗的反应及其与铬积累的关系

Responses of maize seed and seedlings to chromium stress and their relation to chromium accumulation.

研究了铬胁迫对玉米(6个品种)种子萌发初期一些生理生态特征的影响,及各种生理指标与幼苗铬积累量间的关系,结果表明,随铬处理浓度的加大而玉米种子萌发率逐渐降低,幼苗株高、根长、鲜物质量和干物质量均逐渐降低;脯氨酸、吸收铬量、可溶性蛋白质、超氧负离子、丙二醛含量逐渐上升,超氧化物歧化酶(SOD)、过氧化物酶(POD)和过氧化氢酶(CAT)活性则逐渐增加,根系活力和硝酸还原酶活性在不同品种玉米中差异较大;所有供试玉米品种中,丙二醛含量、CAT和SOD活性与幼苗铬积累量之间存在显著或极显著的正相关关系。不同玉米品种对Cr3+毒害的反应表现不同,存在品种间差异。

The effects of CrCl3 stress with different concentrations on some earlier physiological and ecological responses of seed germination, and correlation between physiological index and the contents of Cr^3＋ absorption of Zea rnays were studied. The results showed that seed germination rate, plant height, root length, fresh weight and dry biomass of seedlings gradually decreased with increasing CrCl3 concentrations. While not only the contents of proline, soluble protein, chromium and malonaldehydic acid （MDA） increased, but the activity of superoxide dismutase （SOD）, peroxidese （POD） and catalase （CAT）increased gradually. But the diffrence of root vigor and activity of nitrate reductase （NR） evidently varied among different variety. The positive correlation between Cr^3＋ content and MDA contents, SOD and CAT activity was significant at the 0.01 level or 0.05 level. In a word, different Zea mays variety tend to have different responses to Cr^3＋ toxicity, there are differences among variety.