百里香与小花溲疏叶片气孔特征、叶绿素含量及气体交换日变化研究

Study on Leaf Stomatal Characters,Chlorophyll Content and the Daily Change of Gas Exchange of Thymus mongolicus Rom and Deutzla parviflora Bge

在盆栽条件下对百里香和小花溲疏叶片的气孔特征、叶绿素含量及气体交换日变化进行了比较研究,结果表明:百里香的气孔密度明显高于小花溲疏,且气孔的长与宽比小花溲疏要小;百里香的叶绿素含量比小花溲疏高;百里香和小花溲疏都具有比较典型的双峰型光合速率日进程曲线,它们的气孔导度、蒸腾速率的日变化曲线与净光合速率的日变化基本一致;在一日内百里香净光合速率、气孔导度和蒸腾速率始终大于小花溲疏;百里香叶片气孔的结构特点、叶绿素含量的生理基础以及百里香植株的生物学特点是其净光合速率始终高于小花溲疏的主要原因,也使得百里香较小花溲疏更适应旱生环境。

Comparative study on leaf stomatal characters, chlorophyll content and the daily change of gas exchange of Thymus mongolicus Rom and Deutzia parviflora Bge under pot conditions. The results indicated that：the stomatal density of Thymus mongolicus Rom is clearly higher than that of Deutzia parviflora Bge and the length and width of stomatal are smaller than in. The chlorophyll content in Thymus mongolicus Romis higher than that in Deutzia parviflora Bge. The two- peak pattern photosynthetic rate daily course curve of Thymus mongolicus Rom and Deutzia parviflora Bge are very typical. It＇s daily change curve of stomatal conductance and transpiratdon rate are stmdlar to the daily change of net photosynthetic rate. The net photosynthetic rate, stomatal conductance and transpiration rate in Thymus mongolicus Rom are greater than in Deutzia parviflora Bge all the time.The major reason of Thymus mongolicus Rom＇s net photosynthetic rate higher than Deutzia parviflora Bge all the time is the physiological foundation of stomatal structural character, chlorophyll content of Thymus mongolicus Rom and the biological character. So the Thymus mongolicus Rom is more easily adapt to dry environment than Deutzia parviflora Bge.