【摘要】 为了探讨重金属离子对果树的毒性机制,以草莓(Fragaria ananassa Duch．)主栽品种丰香(Toyonoka)和章姬(Akihime)组培苗为外植体,研究了不同浓度AgNO3对草莓生长及抗氧化酶活性的影响。结果表明,1／2MS培养基中有AgNO3存在时,2个草莓品种的根干质量和根长明显增加,根系活力随着AgNO3浓度的增加而增加,1．0 mg／L时达最大值,而根系含水量则随着AgNO3浓度的增加逐渐降低。AgNO3浓度为0．5-1．0 mg／L时,植株株高和干质量逐渐下降,而叶绿素、可溶性蛋白的含量和抗氧化酶的活性则逐渐增加。叶片中MDA的含量、O2-的产生速率、脯氨酸的含量和IAA氧化酶的活性随着AgNO3浓度的增加而增加,而IAA的含量则逐渐降低。更多还原

【Abstract】 Effects of different AgNO3 levels on the growth and the activities of antioxidant enzymes in two cultivars of Fra-garia ananassa Duch. cv. Toyonoka and Akihime were studied. Half-strength MS medium, containing appropriate concentration of AgNO3 (≤1.0 mg/L) could significantly increase root length, dry weight and activity. Shoot height and dry weights of plantlets were reduced in the presence of 0.5-1.0 mg/L AgNO3 while chlorophyll contents, soluble protein contents, super-oxide dismutase (SOD), peroxidase (POD) and catalase (CAT) activities in leaves were increased and reached the maximum at 1.0 mg/L AgNO3. Superoxide free radicals (O2-) production rate, malondialdehyde (MDA) content, proline content and lAA-oxidase activity in leaves were increased while root water content and indole-3-actic acid (IAA) content was decreased with the addition of 0.5-4.0 mg/L AgNO3.更多还原