tailieunhanh - Systematic implications of seed coat diversity in some representatives of the genus Ipomoea (Convolvulaceae)

Seed coat morphology of 15 species of Ipomoea L. was examined comparatively using scanning and light microscopy methods in order to evaluate their diagnostic value for systematic studies. Macro- and micromorphological characters, including seed shape, colour, size, seed surface, epidermal cell shape, anticlinal boundaries, and periclinal cell wall are presented. | Turkish Journal of Botany Research Article Turk J Bot (2013) 37: 811-824 © TÜBİTAK doi: Systematic implications of seed coat diversity in some representatives of the genus Ipomoea (Convolvulaceae) 1,2, Kadry ABDEL KHALIK * Botany Department, Faculty of Science, Sohag University, Sohag, Egypt 2 Biology Department, Faculty of Science, Umm-Al-Qura University, Mecca, Saudi Arabia 1 Received: Accepted: Published Online: Printed: Abstract: Seed coat morphology of 15 species of Ipomoea L. was examined comparatively using scanning and light microscopy methods in order to evaluate their diagnostic value for systematic studies. Macro- and micromorphological characters, including seed shape, colour, size, seed surface, epidermal cell shape, anticlinal boundaries, and periclinal cell wall are presented. Descriptions of seed size, shape, colour, surface, and seed coat types are summarised for the genus. Taxonomic phylogenetic implications of the seed coat micromorphology are also discussed in comparison with the available gross morphological and molecular data. Results of the seed character analyses offer useful data for evaluating the taxonomy of Ipomoea both on subgeneric and sectional levels. Monophyly of both sections Erpipomoea Choisy and Eriospermum Hallier is not supported. A key for the identification of the investigated taxa based on seed characters is provided. Key words: Ipomoea, cluster analysis, scanning electron microscopy, seed coat, subgeneric classification 1. Introduction Ipomoea L. is a large, diverse genus of the Convolvulaceae comprising over 600 species of vines and shrubs that are widely distributed throughout the tropics and subtropics (Van Ooststroom, 1953; Austin, 1975; Austin and Huáman, 1996; Miller et al., 1999; Stefanovic et al., 2003). The taxonomy and systematics of this critical group are highly controversial and dependent on different