湿地松半同胞家系净光合速率的比较研究及季节变异规律

为研究湿地松半同胞家系间净光合速率的差异及其季节变异规律，应用LI－6400便携式光合测定系统，对湿地松优良半同胞家系一年中各月净光合速率、最大净光合速率进行了研究，结果表明一年中湿地松各半同胞家系1龄针叶、2龄针叶净光合速率、最大净光合速率的季节变异规律呈‘双峰’型，家系内不同单株同龄针叶的净光合速率值没有显著差异，而家系间相同年龄针叶的净光合速率值则存在着显著差异。一年中1龄针叶以家系464、609、1077的净光合速率较高、普通种最低，其值分别为8.17、7.91、7.88和5.46μmol•m-2•s-1，而2龄针叶以家系1077、609、46的净光合速率较高、普通种最低，其值分别为5.47、5.42、5.37和3.65μmol•m-2•s-1。湿地松各家系1龄针叶的净光合速率值、最大净光合速率值显著高于2龄针叶的净光合速率值和最大净光合速率值。各家系1龄针叶的净光合速率值仅为最大净光合速率值的64.41%、2龄针叶的净光合速率值仅为最大净光合速率值的54.44%。表明湿地松高光效育种的改良潜力较大，通过合理利用和调整育林措施，可提高湿地松优良家系的生长量和产量。

Study on the Seasonal Variation and Difference on Net Photosynthetic Rate of Slash Pine' s Half-sib.

The net photosynthetic rate and maximum net photosynthetic rate of slash pine’s half-sib around 1 year is studied utilities of LI-6400 portable photosynthetic system so as to study on the seasonal variation and difference on net photosynthetic rate. The result showed that the seasonal variation of net photosynthetic rate and maximum net photosynthetic rate of slash pine’s half-sib is double range curve. There is no notable difference on net photosynthetic rate among needles with same half-sib. There is notable difference on net photosynthetic rate with same needles among half-sib. The net photosynthetic rate of 1 year needle of half-sib 464 and 609 and 1077 is over than others. The common variety is lowest. The net photosynthetic rate is step by 8.17μmol•m-2•s-1 and 7.91μmol•m-2•s-1 and 7.88μmol•m-2•s-1 and 5.46μmol•m-2•s-1.The net photosynthetic rate of 2 year needle of half-sib 1077 and 609 and 46 is over than others. The common variety is lowest. The net photosynthetic rate is step by 5.47μmol•m-2•s-1 and 5.42μmol•m-2•s-1 and 5.37μmol•m-2•s-1 and 3.65μmol•m-2•s-1.The net photosynthetic rate and maximum net photosynthetic rate of 1 year needle is over than 1 year needle’s. The net photosynthetic rate of 1 year needle decrease by 64.41% against maximum net photosynthetic rate 1 year needle. The net photosynthetic rate of 2 year needle decrease by 54.44% against maximum net photosynthetic rate 2 year needle. The potential of heredity and improvement is very high by breeding on light effective. It can increase growth and yield by adjusting cultivation method.