中籼稻抽穗期耐热性评价方法及应用研究

Evaluation Method for Heat Tolerance of Medium Indica Rice in Heading Stage and Its Application Research

[目的]研究中籼稻抽穗期耐热性的评价方法及应用。[方法]以安徽省生产上推广的30个中籼稻品种为材料,采用分期播种和盆栽方式,利用温室模拟高温热害环境,在抽穗开花时期鉴定其耐热性,根据产量损失的大小,提出水稻抽穗耐热性的评价指标。[结果]根据产量损失的大小,将水稻品种的抽穗期耐热能力分为4类。耐热系数>90%的品种为耐热品种,高温对其结实率有一定影响,但产量损失较小,在10%以下;耐热系数在80%～90%的品种为中度耐热品种,其受高温影响的产量损失在10%～20%;耐热系数在55%～80%的品种为敏感品种,其受高温影响的产量损失在20%～40%;耐热系数<55%的品种为高度敏感品种,其受高温影响的产量损失大于40%。[结论]根据耐热性评价指标筛选出中籼2503、皖稻173和皖稻89等一批强耐热品种。

[Objective]The purpose was to study the method of evaluating the heat tolerance of medium Indica rice in the heading stage and its application.[Method]With 30 varieties of medium Indica rice that were popularized in the production in Anhui Province as the tested materials, using the modes of sowing at different time and cultivating by pots,the heat-harm environment under high temperature was simulated in the greenhouse to identify the heat tolerance of medium Indica rice in heading and flowering stage and the evaluating index of heat tolerance in the rice was proposed according to the size of yield loss.[Result]The heat tolerance ability of the rice varieties in the heading stage was divided into 4 classes according to the size of yield loss.The varieties with the heat-resistance coefficient of90%were the heat tolerance varieties and the high temperature had a certain influence on the seed setting rate of these varieties,but their yield lose was below 10%.The varieties with the heat-resistance coefficients from 80%to 90%were the moderate heat-tolerance varieties and their yield loss was from 10%to 20%by the high temperature influence.The varieties with the heat-resistance coefficients from 55%to 80%were the sensitive varieties and their yield loss was from 20%to 40%by the high temperature influence.The varieties with the heat-resistance coefficients of55%were the highly sensitive varieties and their yield loss was more than 40%by the high temperature influence.[Conclusion]A group of heat tolerance varieties of medium Indica rice such as Zhongxian 2503,Wandao 173 and Wandao 89 were screened out according to the evaluating index of heat tolerance in the rice.