Abstract: Great losses to the rice production are caused by high temperature stress. Using the heat resistant materials screened by International Rice Research Institute, we studied the high temperature stress effect on grain quality of rice in heading and flowering period, the results were as follows: There were big differences of heat tolerance among the heat resistant materials screened by International Rice Research Institute, and there were some materials relatively sensitive to high temperature; high temperature stress greatly affected quality evaluation indexes of rice in heading and flowering period; the changes of rice transparency, length-width ratio, chalky rate, gelatinization temperature, protein content were not related to heat resisting property of rice varieties; under high temperature stress, there was a significant negative correlation between heat resistant coefficient of rice varieties and the change of gel consistency, the correlation coefficient was -0.516 70, and there was a significant positive correlation between the change of amylase content  and heat resistant coefficient of rice varieties, the correlation coefficient was 0.659 78.

Key words: rice, heading and flowering period, high temperature stress, grain quality, heat resisting property

摘要： 高温热害对水稻生产造成了巨大的损失。利用国际水稻研究所耐热圃材料，在抽穗扬花期进行高温处理，研究了该时期高温胁迫对水稻主要品质评价指标的影响，结果如下：水稻耐热圃材料的耐热性有较大的差别，依然存在高温相对敏感材料；抽穗扬花期高温胁迫对水稻主要品质评价指标影响较大；高温胁迫对水稻籽粒的透明度、长宽比、垩白率、糊化温度和蛋白质含量等品质指标与品种的耐热性相关关系不大；高温胁迫下直链淀粉含量变化与品种耐热系数表现出显著的正相关关系（r=0.659 78）；高温胁迫下胶稠度变化与不同水稻品种的耐热系数呈显著的负相关关系（r=-0.516 70）。

关键词: 水稻, 抽穗扬花期, 高温胁迫, 品质指标, 耐热性