摘要
利用Li-6400光合测定系统对苗龄180 d的蹄叶橐吾、多毛蹄叶橐吾和狭苞橐吾盆苗的光合作用日变化规律进行研究。结果表明:①3种橐吾的净光合速率(Pn),气孔导度(Gs)的日变化均为"双峰"型曲线,峰值出现在9:00和15:00时,13:00时左右存在明显的"午休"现象,但不同橐吾的净光合速率和气孔导度的高峰和谷底的高低不同,净光合速率大小依次为:多毛蹄叶橐吾>蹄叶橐吾>狭苞橐吾;②根据Pn、Gs、胞间CO2浓度(Ci)的变化方向,推测3种橐吾的光合"午休"主要受气孔因素限制;③相关性分析表明,3种橐吾Pn与其影响因子Gs之间呈极显著正相关关系,与其他因子呈不显著正或负相关关系;蒸腾速率(Tr)与其影响因子光照强度(PAR),大气温度(Ta),大气湿度(RH)成极显著和显著正相关关系。
Regularity in the diurnal variation of photosynthetic characteristics of 180-day-old seedlings of Ligularia fischeri,L.fischeri f.diabolica and L.intermedia was studied using Li-6400 photosynthesis system.Results showed that the curves of diurnal variation for net photosynthetic rate and stomatal conductance of leaves of the three species of Ligularia had two peaks which appeared at 9：00 and 13： 00,and an obvious midday depression was found at 13： 00.The three species of Ligularia exhibited different peak and valley values of net photosynthetic rate and stomatal conductance.The net photosynthetic rate of L.fischeri f.diabolica was the highest,followed by L.fischeri and L.intermedia.The midday depression in the three species of Ligularia was controlled by stomatal factors according to the changing tendency of net photosynthetic rate,stomatal conductance and intercellular CO2 concentration.Correlation analysis showed that there was a highly significant positive correlation between net photosynthetic rate and stomatal conductance and an extremely significant or significant positive correlation between transpiration rate and light intensity,air temperature and relative humidity.
出处
《东北林业大学学报》
CAS
CSCD
北大核心
2010年第12期38-39,42,共3页
Journal of Northeast Forestry University
基金
环保部科技支撑项目(物种09-二-3-1)资助
关键词
橐吾属
光合特性
日变化
Ligularia
Photosynthetic characteristics
Diurnal variations
