柱花草品种间耐酸铝胁迫差异及其机理初探

Study on differences and mechanisms of Al-stress tolerance among different varieties of S.guianensis

试验采用营养液培养法,研究酸铝胁迫对不同柱花草品种幼苗根系生长和生理性状的影响,比较分析不同品种间的反应差异,并结合土壤盆栽方法进行验证。结果表明:1、用低浓度铝溶液浸泡柱花草种子,种子相对发芽率和幼苗根系生长受到明显抑制,在10μm o l.L-1、30μm o l.L-1和50μm o l.L-1铝浓度胁迫下,热研10号的相对发芽率比其他5个品种都高,而热研13号均为最低;2、在30μm o l.L-1铝溶液胁迫下,幼苗种根相对伸长率受到显著抑制,根尖苏木精染色指数增加,热研10号受抑制最小且根尖着色程度最低,而热研7号和热研13号表现受抑制最大及着色程度最高;3、用30μm o l.L-1铝溶液胁迫处理柱花草幼苗,幼苗根系活跃吸收面积降低,细胞质膜透性和根系活力上升;10d后热研10号的根系活跃吸收面积近4倍大于热研13号;质膜透性及根系活力的变化也显示出不同柱花草品种间的耐酸铝性存在显著差异,热研10号对铝耐受性最强,而热研7号及热研13号对铝最敏感;热研5号、C IAT 184和907的对酸铝胁迫的反应介于两者之间。

The different responses of S. guianensis to Al-stress and the effects of Al-stress on the root growth and physiological characters of seedlings were studied by the means of solution cultivation and pot cultivation. The results indicated that the root growth of seedlings and the germination rates of seed were significantly inhibited in Al solution with low concentration; the germination rate of Reyan 10 was higher than that of other five varieties under the Al-stress of 10 μmol/L, 30 μmol/L and 50μmol/L, while that of Reyan 13 was the lowest. Under the Al-stress of 30μmol/L, the elongation rate of main root of seedlings was inhibited obviously and the hematoxylin dye index of root tip was increased ; the inhibited and the dyeing degree of Reyan 10 were the lowest while that of Reyan 17 and Reyan 13 were the highest. Under the condition of 30μmol/L Al-stress, the active absorptive areas of seedlings decreased and the cytoplasmic membrane permeability of root and root activity increased. After ten days, the root active absorptive areas of Reyan 10 was higher than that of Reyan 13. The changes of membrane permeability and root activity indicated that there were significant differences of Al-tolerance stress among different varieties of S. guianensis , and the Al-tolerance stress of Reyan 10 was the strongest but Reyan 7 and Reyan 13 were sensitive to Al-stress, and the response to Al-stress of Reyan 5, CIAT184 and 907 were intermediate. ence