不同穗重型水稻品种剑叶光合特性的研究

Studies on the Photosynthetic Characteristics of the Flag Leaf of Different Panicle Weight Types of Rice

以 6个典型的不同穗重类型水稻品种为材料 ,对其部分光合生理特性进行了研究。从光合日变化上看 ,重穗型品种冈优 5 2 7一天中不同时间的净光合速率均显著高于中穗型品种汕优 6 3和轻穗型品种密阳 46 ,特别是中午光合“午睡”现象较轻 ;从光—光合曲线看 ,其量子效率差异较小 ,饱和光强下冈优 5 2 7的净光合速率比汕优 6 3和密阳 46分别高 9.6 %和 17.8%;在 10 0～ 30 0 μL/ L CO2 浓度下 ,冈优 5 2 7净光合速率上升最快 ,汕优 6 3次之 ,密阳 46最低 ;冈优 5 2 7和密阳 46的光合最适温度均在 35℃左右 ,较汕优 6 3(30℃左右 )高。气孔开度总量 (单位面积叶片上的气孔密度乘以其气孔开度 )大是净光合速率高的重要生理基础之一。

The photosynthetic characteristics of different panicle weight types of rice were studied. The results indicated that the photosynthetic rate of Gangyou 527(heavy-panicle) was higher than that of Shanyou 63(middle-panicle) and Miyang 46(light-panicle), especially under saturated light intensity conditions, The photosynthetic rate of Gangyou 527 was 9.6% and 17.8% higher than that of Shanyou 63 and Miyang 46 respectively under saturated light intensity. Under CO 2 concentration of 100～300 μL/L, the increase of photosynthetic rate of Gangyou 527 was the highest, Shanyou 63 the second, and Miyang 46 the lowest. The optimum temperature for photosynthesis of Gangyou 527 and Miyang 46 were about 35 ℃, and that of Shanyou 63 was about 30℃. It was suggested that the higher photosynthetic rate of the heavy panicle of rice might be result of their higher total quantity of stomatal opening degrees.