常绿阔叶植物越冬期间叶片组织结构的适应性变化

 在北京自然越冬条件下, 黄杨叶片组织结构变化最为明显, 叶肉海绵组织分层, 被认为是避免胞内结冰的适应性变化。黄杨、扶芳藤、大叶黄杨、八角金盘、洋常春藤、女贞、广玉兰、火棘等超微结构均发生明显变化, 主要发生在叶绿体、脂质体、液泡膜及原生质膜。叶绿体的破坏及修复、液泡膜的活动特点及质壁分离程度都表现出和物种越冬能力的相关性。气孔行为及叶表皮蜡质的变化也与植物抗寒性有一定相关性。表明常绿阔叶植物在秋冬可以通过结构上的适应性变化提高抗寒性, 但种间差异明显。

Change of the Leaf Tissue Structure of Evergreen Broad-leaf Plants during Overwintering

In Beijing open garden,the leaf structure of Buxus sinica changed with the emerging of isolated layer in the spongy tissue,and is regarded as the adaptable change of avoidance of ice formation intracellular and promoting ice formation extracellular.The chloroplast,lipid granule,vacuolar memebrane and protoplast are the apparatus which change most obviously in the ultro microstructure in all tested species.Their changes,as well as the stomatal opening response and the change of character in the lower epidermis are related to the overwintering ability.