不同核桃品种光合特性比较研究

Photosynthetic Characteristics of Different Varieties of Juglans regia

用Li-6400便携式光合作用测定系统,对香玲、鲁光、清香、西林3号、西洛3号5个核桃品种的光合生理特性进行了研究。结果表明,5个品种的净光合速率日平均值大小顺序为香玲>鲁光>清香>西林三号>西洛3号。净光合速率日变化、蒸腾速率日变化和气孔导度日变化曲线均呈单峰型和双峰型;不同品种净光合速率与蒸腾速率、气孔导度,蒸腾速率与气孔导度均呈极显著正相关(P<0.01);香玲品种核桃苗叶光补偿点、光饱和点分别为58.997、1 450μmo1·m-2·s-1。

The photosynthetic characteristics of five varieties of Juglans regia were studied by using the Li--6400 Portable Photosynthesis System. The results showed that the average net photosynthetic rate follows the order from high to low：Xiangling, Luguang, Qingxiang, Xilin3 and Xiluo3. The diur- nal variation curves of net photosynthetic rate （Pn） ,transpiration rate （Tr） and stomatal conductance （Gs） among different five varieties were different, showing two types, single peak curve and double peak curve. Correlation analysis among photosynthetic parameters showed that there were significantly positive correlations（P〈0.01） among Pn and Tr,Pn and Gs,Tr and Gs. Though light response curves of xiangling,the light compensation point is about 58. 997 mol m-2 s-1 and the light saturation point is 1450 mol m-2 s-1.