中文摘要：

采用田间试验研究了421个常规籼稻、63个常规粳稻和82个籼型杂交稻品种种子含氮量的基因型差异.结果表明,栽培稻种子含氮量变幅在0.85%～2.55%,平均为1.39%.种子平均含氮量最高的是籼型杂交稻,高达1.46%,显著高于常规粳稻（1.39%）和常规籼稻（1.37%）.不同类型的栽培稻种子含氮量呈正态分布,但频数分布最高的区间存在一定的差异.以50%品种的种子含氮量（累积百分数从25%～75%）为依据,常规籼稻、常规粳稻、籼型杂交稻分别集中在1.21%～1.52%、1.21%～1.51%、1.36%～1.53%.LSR测验表明,籼型杂交稻极差显著小于常规籼稻和常规粳稻,但常规粳稻与常规籼稻的差异未达显著水平,即籼型杂交稻种子含氮量比常规籼稻和常规粳稻的分布更加集中.不同类型栽培稻内的种子含氮量极差较大,可分为若干组,且各组间达极显著差异.

英文摘要：

Field experiments were conducted at Jiangxi Agricultural University to study the genotype difference of seed nitrogen content in 412 indica rice, 63 japonica rice, and 82 indica hybrid rice varieties. The results showed that the seed nitrogen content of cultivated rice had a significant genotype difference, with the range from 0.85 % to 2.55 %, and an average of 1.39 % . The average seed N content of indica hybrid rice was 1.46 %, which was significantly higher than that of japonica normal rice （ 1.39 % ） and indica normal rice （1.38 % ）, and there was no significant difference between indica and japonica normal rice. The frequency distribution of seed N content exhibited normal curve, but the centers of frequency distribution were different among three rice types. The ranges of the cumulated frequency from 25% to 75% were 1.21% - 1.52%, 1.21% - 1.51% and 1.36 % - 1.53 % for indica, japonica, and indica hybrid rice, respectively. Ducan＇s Mutiple Range test showed that the maximum derivation of N content among indica hybrid rice varieties was significantly lower than that among indica and japonica rice, which indicated that the seed N content of indica hybrid rice was more concentrated than that of indica rice and japonica rice. The maximum derivation within different cultivated rice types was very large. Thus, each rice type could be classified into several groups, and the difference between groups was significant.