计算生物学在杂交稻全生育期抗热性评价中的应用

Abstract

采用玻璃温室增温法，以产量及其性状(穗长、一次枝梗数、二次枝梗数、总粒数、空粒数、穗数、千粒重、结实率、着粒密度和单株产量)的抗热响应、感热指数和几何均值为抗热性指标，对37个杂交稻组合进行了全生育期抗热性的评价。结果表明，不同杂交稻组合产量及其性状对全生育期高温的响应、感热指数和几何均值存在着显著基因型差异，对高温的响应和性状感热指数以二次枝梗数为最大和结实率为最小，性状几何均值以空粒数为最大和穗长为最小。相关分析发现，千粒重、结实率的性状响应和感热指数与抗热系数呈极显著相关，总粒数和着粒密度的几何均值与抗热系数呈极显著相关。以综合响应、性状热感指数和性状几何均值的综合抗热力为依据对杂交稻组合的抗热性进行聚类和判别分析发现，三种间接评价方法结果与抗旱系数直接评价结果并不完全一致，吻合度最好的是性状热感指数(70.27%)，而综合性状居中(59.50%)，性状几何均值最差(48.65%)。因此，产量性状感热指数的综合抗热力可作为杂交水稻抗热性间接评价的可靠方法和指标。 With increasing temperature with glasshouse, the heat resistances and responses of 37 hybrid rice combinations to high temperature in whole stage were analyzed and evaluated with the heat susceptibility index, heat resistance coefficient and geometric mean in yields and their traits (panicle length, primary branches, secondary branches, total grains, no-filled grains, panicle number, 1000-grain-weight, seed-setting rate and grain density). The results showed that heat susceptibility indexes, heat resistance coefficient and geometric means in yields and their traits of 35 hybrid rice combinations to high temperature in whole stage were significantly genotypic differences. The maximum and minimum responses or heat susceptibility indexes of traits were respectively those of secondary branches and seed-setting rate. The maximum and minimum geometric means of traits were respectively those of no-filled grains and panicle length. Correlations of heat response or susceptibility indexes of 1000-grain-weight and seed-setting rate, geometric mean of total grains and grain density to heat resistance coefficient were significant at 0.01 level. The clustering and discrimination analyses of heat resistance in 37 hybrid rice combinations were conducted according to the comprehensive heat resistances of responses, heat susceptibility indexes and geometric means in yields and their traits, which indicated that the results had no fully common with the direct evaluation according to heat resistance coefficient, and the best consistency (70.27%) with heat susceptibility indexes, the next (59.50%) with geometric means and the worst (48.65%) with comprehensive responses. Therefore, comprehensive heat resistance of heat sus- ceptibility indexes in yields traits was the dependent method and index of indirect evaluation on rice heat resistance, the maximum effect with 1000-grain-weight and seed-setting rate.