摘要
以50μmol/L Cd胁迫培养13个品种的小白菜,通过形态指标和生理生化指标的测定,探讨其Cd耐性形成的生理生化应答机制。结果表明:Cd胁迫下,供试材料生长和生理生化代谢均不同程度受到抑制,但与其茎叶Cd累积量无直接关系,且不同品种小白菜对Cd耐性不同。对供试材料Cd耐性指数(Tolerance index,TI)分析表明,基于植株干物质累积的耐性指数(TI-P)与基于茎叶生长的耐性指数(TI-S)极显著相关(R2=0.686),而前者与基于根系生长的耐性指数(TI-R)的显著相关(R2=0.349)。可见,以基于茎叶生长的耐性指数比基于根系生长的更能反映小白菜的Cd耐性。Cd胁迫条件下,供试材料体内脯氨酸(Pro)、丙二醛(MDA)含量以及抗坏血酸过氧化物酶(AsA-POD)和超氧化物歧化酶(SOD)活性都有不同程度的提高。Cd胁迫下,各品种叶片脯氨酸增量、SOD活性增量均与供试小白菜Cd耐性正相关,二者可作为供试材料Cd耐性的生化指标。
Thirteen cabbage（Brassica chinensis ）cultivars were cultured hydroponically with 50μmol/L cadmium to analyze their physio-chemical response to CA stress. The results show some degree of inhibition on growth and physio-chemieal metabolism in cabbage due to Cd stress regardless of CA accumulation in shoots. There is always CA tolerance effect though it varies with cultivar type. Through analysis of Cd tolerance index（TI）among the 13 selected cabbage cultivars, correlation coefficient between TI-P（TI based on plant dry matter accumulation） and TI-S（TI based on shoot growth）is noted to be more significant than that between TI-P and TI-R（TI based on root growth） , implying that TI-S is a more appropriate criterion than TI-R in morphological evaluation of cabbage CA tolerance. Meanwhile, proline and malondialdchyde（MDA） contents, and AsA-POD and SOD activities in tested cabbage shoots increase variously under CA stress. In particular, the increases of proline content and SOD activity（under CA stress）are correlated positively with TI-S, implying their feasibility as physio-chemical indices in CA tolerance analyses.
出处
《中国生态农业学报》
CAS
CSCD
2007年第5期120-124,共5页
Chinese Journal of Eco-Agriculture
基金
国家自然科学基金(30571138)
福建省自然科学基金项目(B0520001)资助
关键词
CD胁迫
小白菜
重金属耐性指数
细胞保护酶体系
生理生化应答
Cadmium stress, Cabbage （Brassica chinensis ）, Heavy metal tolerance index, Protective enzymes system,Physio-chemical response
