Taxonomic significance of the structure of the rachis, petiole and petiolule i meliaceae

摘要

Anatomy of the rachis, petiole and petiolule in 15 species distributed over 13 genera of Meliaceae is investigated. The mechanical tissues in these organs are invariably sclerenchymatous and rarely collenchymatous. Vascular tissue in the form of distinct bundles, an arc-shaped strand or a continuous cylinder is noted in dilterent organs. Medullary bundles occur in Walsura and Aglaia,. while cortical bundles are present in Apbanamixis and Kbaya. Both the types are seen in Soymida. A key based on the anatomical characters of the leafstalk is provided for the delineation of the taxa studied.