6种睡莲叶片解剖结构及耐寒性评价

Leaf Anatomic Structure and Cold Tolerance Evaluation of 6 Nymphaea Varieties

对6种睡莲的10项叶片解剖结构指标进行观测,并通过聚类分析和隶属函数法评价睡莲的耐寒能力。结果显示睡莲为异面叶,气孔仅分布于上表皮,上表皮厚度小于下表皮厚度。各种间叶片厚度差异均显著,夜雪睡莲的叶片结构最为紧密,白睡莲则最为疏松。通过聚类分析,将10项指标分为3类,各类中相关指数最大的分别为叶片总厚度、气孔密度和栅海比,以此作为评价睡莲叶片耐寒性的主要指标。6种睡莲的耐寒能力为白睡莲>夜雪睡莲>齿叶睡莲>永恒睡莲>蓝星睡莲>袖珍睡莲。

10 leaf anatomical indexes of 6 Nymphaea species were observed and measured,and the cold tolerance was evaluated by cluster analysis and membership function.The result showed that Nymphaea is a bifacial leaf,stomata is only distributed in upper epidermis,and the thickness of upper epidermis was smaller than that of lower epidermis.Leaf thickness has significant differences and Nymphaea potamophila had the most compact leaf structure while N.alba had the most loose.Through cluster analysis,10 indicators were divided into 3 categories,and indicators with the largest correlation coefficients were leaf thickness,stomatal density andpalisade tissue-spongy tissue ratio,which were found to be the main factors to evaluate the cold resistance of different Nymphaea species.The order of the six species based on cold tolerance from strong to weak is N.alba >N.potamophila>N.lotus>N.immutabilis>N.colorata>N.minuta.