UNDERSTANDING DIVERSITY IN LEAF SHAPE OF CHINESE SAGITTARIA (ALISMATACEAE) BY GEOMETRIC TOOLS

Abstract

Plants of Sagittaria generally possess different leaf shapes, but these shapes were rarely quantified. In this study, all species of Chinese Sagittaria were collected, and their leaf shapes were analyzed using two geometric tools: Topological description and geometric morphometric analysis. The leaf shapes of Chinese Sagittaria can be divided into three major groups according to topological types of the venation architecture, and the variation of leaf shape is closely related to the development degree of Sagittaria plants. Even if corresponding to the same venation pattern, many leaf shapes have evident differences which could be revealed by geometric morphometric analysis, and these differences show species specificity to a great extent. Making use of these results, some misunderstandings in the taxonomy of Sagittaria also be cleared up.