使用LI-6400便携式光合测定系统,研究了湿地松优良半同胞家系的光和CO2响应情况,结果表明：不同湿地松半同胞家系光响应曲线、CO2响应曲线的特征参数在家系品种间有极显著差异。湿地松各半同胞家系1龄针叶在全年中以3至4月份、2龄针叶以4月份的表观光量子效率为最高,所有针叶以5月份最低, 各家系1龄、2龄针叶的羧化效率以5月最低,8至9月最高。所有家系的1龄针叶、2龄针叶的表观光量子效率、羧化效率均高于普通品种,1龄针叶的表观光量子效率、羧化效率要高于2龄针叶的。具有较高的表观光量子效率、羧化效率、光饱和点、CO2饱和点和较低的光和CO2补偿点,是湿地松优良半同胞家系具有较高生长量和产量的主要生理原因。

The responses to light and CO2 of slash pine’s halfsib were studied for establishing reasonable strategy in heredity improvement and planting using LI-6400 portable photosynthetic system. There were significant differences of the character parameters which responded to light and CO2 of slash pine’s halfsib. The apparent quantum yield on March to April of 1 year needle of slash pine’s halfsib and the apparent quantum yield on April of 2 year needle of slash pine’s halfsib was the highest in a year. The apparent quantum yield on May of 1 and 2 year needle of slash pine’s halfsib was the lowest. The carboxylation efficiency on May of 1 and 2 year needle of slash pine’s halfsib was the lowest while the carboxylation efficiency on August to September of 1 and 2 year needle of slash pine’s halfsib was the highest.The apparent quantum yield and carboxylation efficiency of slash pine’s halfsib were higher than that of general variety. The apparent quantum yield and carboxylation efficiency of 1 year needle were higher than that of 2 year needle’s. The main physiological mechanism of fast growth and high yield of slash pine’s halfsib was that it had highest apparent quantum yield, carboxylation efficiency, saturation point of light, saturation point of CO2 and lower compensation point of light , compensation point of CO2.