中文摘要：

重金属镉作为毒性较高的环境毒物，不仅危害植物的生长和发育，也对人类健康带来严重威胁。以小麦为试验对象，在200μmol·L^-1镉胁迫下，研究了错对小麦种子萌发及幼苗生理特性的影响，研究结果表明，200μmol·L^-1镉胁迫下，小麦种子萌发过程中根生长、根尖细胞有丝分裂指数、α-淀粉酶、APX及CAT的活性明显受到抑制，而MDA含量明显增加。20～80mg·L^-1错浸种24h，对200μmol·L^-1镉胁迫下小麦种子的萌发及根、芽的生长具有一定缓解作用，且以40mg·L^-1镨的效果最好，在该浓度下，根长、根鲜重、发芽指数及活力指数明显提高；同时，可提高根尖有丝分裂指数，增强α-淀粉酶活性，提高抗氧化能力，使MDA含量显著降低。然而，100—150mg·L^-1的镨浸种后，种子活力及幼苗生长下降，根尖细胞分裂指数、α-淀粉酶活性降低，MDA含量增加。

英文摘要：

Cadmium （Cd） is a highly toxic and persistent environmental poison. Its increasing level in soil environment exerts a wide range of adverse effects on plants and even the healthy of human beings by food chains. In the study, the possible effects of Pr on wheat seeds germination, seedlings growth and physiological characteristics under cadmium toxicity were studied. The results showed that the 200 μmol ·L^-1 Cd significantly inhibited root elongation, mitotic index of root tip, the activities of α-amylase, ascorbate peroxidase （APX） and catalase （CAT） and increased the content of MDA as compared to the control. The 20 - 80 mg ·L^-1 Pr could promote growth of root and shoot under 200 μmol ·L^-1 Cd stress, and 40 mg ·L^-1Pr exhibited the most prominent alleviating effect. The 40 mg ·L^-1 Pr could significantly increase root elongation, root fresh weight, germination index and vigour index, mitosis index of root tip, α-amylase, as well as oxidation resistance, whereas MDA content decreased significantly. However, 100 - 150 mg ·L^-1 Pr could decrease seed vigour and seedling growth, root mitosis, α-amylase activity, and increase MDA content.