中文摘要：

为了解小麦对铬的抗性机理，以两个铬（Cr）抗性不同的小麦品种鲁麦22（抗Cr）和周麦9号（Cr敏感）为材料，采用水培试验研究了Cr胁迫下小麦幼苗的生长特性、对Cr积累能力的差异及其耐性机理。结果发现，Cr胁迫降低了两个小麦品种的干物质积累量、根长、根表面积、株高和叶面积，耐Cr品种鲁麦22受抑程度较周麦9号轻。两个小麦品种的根系和地上部总Cr含量、细胞壁Cr含量及可溶性Cr含量均随Cr处理浓度的增加而升高，且根系中Cr含量显著高于地上部。鲁麦22根系与地上部总Cr含量的比值显著高于周麦9号；根系及地上部细胞壁Cr舍量与总Cr含量的比值也显著高于周麦9号，而可溶性Cr与总Cr含量的比值显著低于周麦9号。Cr处理显著增加了两个小麦品种的根系和叶片中植物螯合肽（PCs）、可溶性蛋白和游离氨基酸的含量，且鲁麦22的增幅显著高于周麦9号。研究表明，抗cr小麦品种具有更强的阻碍Cr向地上部转运的能力，其植株Cr主要分布于根系和地上部细胞壁中，细胞质内Cr含量较低，受Cr毒害程度降低；PCs、可溶性蛋白和游离氨基酸可能与植物细胞的Cr解毒有关。

英文摘要：

Hydroponic experiment was conducted using two wheat cultivars with differential responses to Cr stress as Lumai 22 （Cr-tolerance） and Zhoumai 9 （Cr-sensitivity） to investigate the genotypic differences in Cr absorption and seedling growth. The results showed that the plant dry weight,total root length,root surface area,shoot height and leaf area of both cultivars decreased compared to con- trol with Cr stress,while Lumai 22 depressed less than Zhoumai 9. The contents of total Cr,cell wall bounded Cr and water soluble Cr in roots and shoots increased with increasing solution Cr concentra- tions with higher in roots than in shoots. For Lumai 22, the ratio of Cr in roots to shoots was much higher than that in Zhoumai 9. Moreover, the ratio of cell wall-bounded Cr to total Cr in roots and shoots of Lumai 22 were significantly higher than those in Zhoumai 9,hut the ratio of water soluble Cr to total Cr were opposite. Cr treatments significantly increased the concentrations of phytochelatins （PCs）, soluble protein and free amino acids in roots and leaves of two wheat, but the magnitudes were er capacity of repressing Cr translocation to shoots,and then distribute more Cr in cell walls to inhibit transmembrane transport which contributed to alleviate Cr toxicity; and the PCs, soluble protein and free amino acids probably participated in the Cr tolerance mechanism in the cells.