Abstract: To investigate the effect of N level on Fe content in milled rice and its genotypic difference, a field experiment was carried out under three N levels including 0, 150 and 300 kg/hm2 by using 120 rice genotypes from domestic and abroad as materials. In addition to the genotypic difference of Fe content in milled rice, yield, 1000grain weight and N content in grain under the same N level, there were also variations in the response of Fe content in milled rice to N level. Based on the range and coefficient of variation for Fe content in milled rice under three N levels, the response of Fe content in milled rice to N levels could be classified into four types including highly insensitive type, insensitive type, sensitive type and highly sensitive type. A significant quadratic correlation was found between the Fe content in milled rice and 1000grain weight or between the Fe content in milled rice and N content in grain. However, no significant correlation between the Fe content in milled rice and yield was detected. In conclusion, there is genotypic difference in the effect of N level on Fe content in milled rice. Therefore, it is favorable to the breeding of Ferich rice which is suitable for a variety of N environments by using the difference. Meanwhile, high yield and Ferich rice could be grown through the regulation of N on Fe content in milled rice, 1000grain weight and N content in grain as affected by N level.

Key words: rice, iron content, genotype difference, nitrogen

摘要： 以120份国内外水稻基因型为材料，设置0、150、300 kg/hm2 3个氮素水平，研究施氮处理对水稻精米中Fe含量的影响及其基因型差异。除相同氮素条件下水稻精米中的Fe含量、产量、千粒重及籽粒含氮量存在基因型差异外，精米中的Fe含量对氮素反应的敏感性也存在显著差异。以各基因型水稻在不同氮素条件下精米中Fe含量的极差和变异系数为指标，通过系统聚类的方法，可将上述120份水稻基因型对氮素反应的敏感性分为极钝感型、钝感型、敏感型和极敏感型共4种类型。同时，相关性分析表明，水稻精米中的Fe含量与产量的相关性不显著，而与粒重、籽粒含氮量呈显著或极显著的二次曲线关系。由此说明，施氮处理对水稻精米中Fe含量的影响具有基因型差异，充分利用这种差异一方面有利于对氮环境适应性强的富铁水稻的选育；另一方面，由于精米中的Fe含量与产量无必然联系，可通过氮肥对水稻（尤其是敏感和极敏感类型水稻）精米中的Fe含量和粒重、籽粒含氮量的调节，实现富铁、高产水稻的种植。

关键词: 水稻, 铁含量, 基因型差异, 氮素