Abstract: A solution culture experiment was conducted to study the effects of P on growth and physiological parameters of two rice genotypes, Azucena (tolerant genotype) and IR64 (sensitive genotype) under excessive Fe²⁺ stress. Results showed that Fe²⁺ stress significantly inhibited the growth of rice shoot and root and decreased the chlorophyll content in rice leaf. The negative effect of Fe²⁺ on rice growth could be ameliorated by increasing P level in the cultural solution. The ameliorating effect of P was more pronounced on the tolerant genotype, Azucena than that on sensitive genotype, IR64. P addition reduced malondialdehyde content and plasma membrane permeability and increased peroxidase activity in the leaves. It suggested that P may play an important role in increasing rice resistance to excessive Fe²⁺ stress.

Key words: phosphorus, excessive ferrous ion stress, rice, lipid peroxidation, antioxidase

摘要： 采用溶液培养法研究了高Fe2+胁迫下不同磷水平对粳稻Azucena（耐铁毒基因型）和籼稻IR64（铁毒敏感基因型）的生长和生理特性的影响。结果表明，与正常供Fe2+相比，高Fe2+胁迫抑制了水稻地上部和根系的生长，降低了干物质积累量和叶片叶绿素含量。外源供磷水平的提高，水稻地上部和根系生长受铁毒抑制程度有所减弱，叶片丙二醛含量和质膜透性下降，POD活性和叶绿素含量增加，而SOD活性则有所下降。表明在一定程度上，磷营养对提高水稻的耐Fe2+毒害具有重要作用，而磷对缓解Azucena的Fe2+毒害的效果较为明显。

关键词: 磷素, 高亚铁离子胁迫, 水稻, 脂质过氧化