镉硫交互处理对水稻吸收累积镉及其蛋白巯基含量的影响

EFFECTS OF SULFATE AND CADMIUM INTERACTION ON CADMIUM ACCUMULATION AND CONTENT OF NONPROTEIN THIOLS IN RICE SEEDLING

研究了不同硫镉浓度组合短期处理 (6d)对水稻幼苗吸收累积镉的影响及其植株体内蛋白质和非巯基硫蛋白含量的变化。结果表明 ,短期单镉胁迫处理下 ,水稻幼苗的生物量没有明显变化 ,但是镉硫交互作用明显地影响镉在水稻苗中的累积。供硫处理能有效地增加镉在水稻叶片中的累积。不同镉、硫处理下植株体内缓冲液可提态蛋白质含量变化不明显。镉胁迫明显增加植株体内NPT含量 ,尤其是根中NPT的含量。供硫也能显著地提高NPT的含量。硫镉交互作用对植株体内NPT含量的影响更为明显。上述结果证实 ,介质中硫的充分供应在有效地提高植物对镉胁迫耐性的同时 ,也显著地促进镉在水稻地上部的积累。

Accumulation of cadmium and nonprotein thiols (NPT) in rice (Oryza sativa L.) seedling as affected by short-term treatment of different combinations of sulfate and cadmium was studied. The results showed that short-term(6 days) Cd stress did not cause significant decline of the seedling biomass, but the interaction between cadmium and sulfate did affect cadmium accumulation in rice seedlings. It was observed that increasing sulfate supply could considerably enhance cadmium transport from root to shoot, thus resulting in higher accumulation of cadmium in leaf. Both of cadmium only stress and higher level of sulfate supply increased NPT content in seedlings, particularly in roots, although level of the phosphate buffer-extractable proteins in plants was kept on changed. Supply of cadmium and sulfate together could further increase NPT content in seedlings, indicating a positive effect of the interaction on NPT. It was concluded that sufficient supply of sulfate could improve rice tolerance to cadmium stress but also enhance cadmium accumulation in the leaf.