籼型杂交稻光合特性的杂种优势分析

摘要

To verify the heterosis of photosynthetic characteristics of flag leaves,thirty hybrid rice combinations and their parents′were tested. The result were as follows,there were significant differences (P<0. 01) for the pho-tosynthetic characteristics in both the hybrid rice combinations and their parents. Among those parameters,photosyn-thetic rate had the biggest coefficient of variation in parents but stomatal conductance had the biggest in hybird rice cornbinations. And the rate of chlorophyll content ( a) and chlorophyll ( b) had the smallest both in parent and hy-bird rice combinations. The average of photosynthetic rate,stomatal conductance and transpiration rate of hybrid rice combinations were bigger than that of the parents. It indicated that it is conducive to breed high photosynthetic rate of hybrid rice combinations. Mid-parent heterosis were found in photosynthetic rate,stomatal conductance and tran-spiration rate,over high-parent heterosis were found in photosynthetic rate and stomatal conductance,below low-par-ent heterosis was found in intercellular CO2 concentration,positive competitive advantages were found in transpira-tion rate and the rate of chlorophyll content( a) and chlorophyll ( b) . Transpiration rate of hybrid rice combinations were positively correlated with that parameters of male parent and mid-parents ( P<0 . 05 ) .%为探明籼型杂交稻光合特性的杂种优势，以30个杂交稻组合及其亲本为材料，对其功能叶片的光合特性进行了测定和分析，结果表明：亲本间和杂交稻组合的光合性状均存在极显著的差异，其中亲本间变异系数最大的是净光合速率，组合间变异系数最大的是气孔导度，亲本和组合间的变异系数均以叶绿素a/b比值为最小；杂交稻组合净光合速率、气孔导度和蒸腾速率的平均数均大于亲本的平均数，有利于高光合速率杂交稻品种(组合)的选育；净光合速率、气孔导度和蒸腾速率具有正向平均中亲优势，其中净光合速率和气孔导度具有正向超高亲优势，胞间CO2浓度具有负向超亲优势，蒸腾速率和叶绿素a/b比值具有正向竞争优势；杂交稻组合的蒸腾速率与其父本值和中亲值呈显著的正相关关系。