不同海拔裂叶沙参和泡沙参气孔形态的对比研究

Comparative Study on Stomatal Morphology of Adenophora lobophylla and A. Potaninii in Different Altitude

以近缘广布种泡沙参作为对照．在不同海拔高度。对濒危植物裂叶沙参的气孔形态进行了研究。结果表明：裂叶沙参和泡沙参气孔复体类型均为不规则型．但2种沙参气孔器的形态特征具有明显差异。泡沙参叶片气孔保卫细胞角质层较厚．气孔口较小；裂叶沙参和泡沙参的气孔密度与气孔大小成反比，但泡沙参的气孔随海拔升高而减小．气孔密度随海拔升高而增大．是抗旱适应的一种表现：因裂叶沙参气孔导度和气孔密度等气孔生理特性低于泡沙参。其使光合速率和蒸腾速率等生理指标也发生明显变化．而导致营养生长不良。幼苗生活力减弱．这是其种群濒危的主要原因之一。

The stomatal morphology of the endangered species A. lobophylla in different altitude was studied bycomparing with the closely related and widely distributed species A. potaninii. The results indicated thatthe stomatal complex of A. lobophylla and A. potaninii are all irregular type. but evident differencesbetween them were found, the stomatal guard cell cuticle of A. Potaninii is quite thick and the stomatalopening is small; the density and size of stomata of A. lobopyylla and A. Potaninii is in an inverseproportion, with altitude increasing the sizes of stomata of A. potaninii decrease, and the densities ofstomata increase. Stomatal physiological characteristics of A. lobophylla are lotver than those of A.potamnu, which make photosynthesis rate and transpiration rate change evidently, thereby lead tonutrition growth unhealthy, and that the seedling ability of 1if e weakening is one of the main cause ofpopulation endangered.