外源精胺对镉胁迫下苎麻生理代谢的影响

采用水培实验法,研究了不同浓度和不同施加方式下外源精胺对苎麻镉污染毒害的缓解效应.结果表明,镉胁迫(10mg/L)使苎麻叶绿素、类胡萝卜素和可溶性蛋白质含量均不同程度地下降,膜脂过氧化程度提高,丙二醛含量增加;加入外源精胺后(以10^-5mol/L效果最佳),叶绿素、类胡萝卜素和可溶性蛋白质含量均显著上升,膜脂过氧化产物丙二醛含量明显降低,说明苎麻对镉的抗性得到显著提高,其中叶面喷洒并同时向营养液中加入精胺能更有效地缓解叶片的生理伤害,而仅叶面喷洒外源精胺则更有利于缓解根中镉的毒害.进入苎麻体内的镉约73.2%积累在根部,2种方式加入精胺均使得镉在苎麻体内的累积量下降,同时镉向地上部分的转移率提高.

Influence of exogenous spermine on the physiological metabolism of ramie under Cd stress

Modification of cadmium (Cd) toxicity in ramie by exogenous spermine (Spm) with different concentrations and adding modes were researched under hydroponic conditions. The treatment of ramie with 10mg/L Cd during 72h induced decrease in chlorophyll, carotenoid and dissoluble protein content along with enhanced lipid peroxidation and malondialdehyde (MDA) content. Spm applied, in particular 10-5 mol/L, significantly alleviated Cd toxicity and enhanced plants resistance to Cd, as evidenced by significant increase in the level of chlorophyll, carotenoid and dissoluble protein as well as decreased MDA concentration. Physiological injury resulted from Cd toxicity in leaf was better relieved in the way of spraying Spm with adding it into the nutritive solution simultaneously. While the damage caused by Cd in root was mitigated more effectively by spraying Spm on leaf alone. Approximately 73.2% of the total Cd in ramie was retained in root. Spm added in both ways decreased the amount of Cd accumulated in ramie and concomitantly increased the translocation factor.