不同玉米品种种子萌发期耐镉性分析

Analysis on Cadmium Tolerance of Different Maize Varieties during Seed Germination Stage

为探明不同玉米品种种子耐镉性差异,以湘中地区主要栽培的21个玉米品种为材料,研究了镉胁迫(50 mg/L)对不同玉米种子的萌发率、发芽指数、活力指数、根芽生长及鲜质量的影响。结果表明:镉胁迫对玉米种子的萌发率、发芽指数影响较小,而对活力指数、根及芽生长影响明显,且镉胁迫对根的抑制作用明显大于对芽的抑制。对综合抑制效应值进行聚类分析,将供试品种划分为敏感型、中间型和耐受型3种类型,其分别占参试品种的4.76%、52.38%和42.86%;其中耐受型品种中黔单12耐镉性较强,大禹甜糯2000、吉玉3号、三北2号、精品美糯2号和美玉10号等5个品种耐镉性较弱,都市丽人、农大3138和糯霸天下等三个品种耐镉性中等。

To ascertain the maize difference of cadmium tolerance, twenty-one varieties widely cultivated in central Hunan were used to analyze the effect of cadmium stress(50 mg/L) on seed germination rate, germination index, vigor index, growth and fresh mass of root and shoot of different maize varieties. The results showed that the seed germination rate and germination index were less affected, and vigor index, the growth of root and shoot were restrained evidently, and the inhibitory of cadmium stress was larger on the growth of roots than that of shoots. Based on the comprehensive effect of clustering analysis to cadmium, the twenty-one varieties were divided into three different types: sensitive, intermediate and tolerant, which accounted for 4.76%, 52.38% and42.86% respectively. Among the tolerant varieties, Qiandan12 was the tolerant type with a relatively strong cadmium tolerance, Dayutiannuo2000, Jiyu3, Sanbei2, Jingpinmeinuo2 and Meiyu10 belonged to the categories with weak cadmium tolerance, and Dushiliren, Nongda3138 and Nuobatianxia belonged to the tolerance of intermediate type.