Petiolar Anatomy as an Aid in Taxonomy of the Genus Ixora L. (Rubiaceae)

C R Patil,D A Patil

doi:10.32439/ps.v3i6.89-94

Abstract

The present authors investigated petiolar anatomy of 12 species of the genus Ixora L. (Rubiaceae). The petioles (in T.S.) are horse shoe-shaped, planoconvex or circular in outline. They are usually winged and channeled adaxially. The extent of development of various tissues and their distribution, besides the cell inclusions, are observed. The vasculature is resolved into a conspicuous central arc, besides few other vascular bundles. The central arc is horse shoe-shaped, heart-shaped, circular, lunar or crescent shaped. The vascular arcs or bundles are capped abaxially by few sclerenchymatous layers, except few. The shapes of petiole, petiolar wings, features of epidermis, patterns of vascular supply and association of sclerenchyma with it, cell contents, etc. are thought systematically important. All these features are employed to prepare a key helping identification of the taxa investigated.

Highlights

The genus Ixora L. (Rubiaceae) contains nearly 100 species (Hooker,1872-1897) and distributed in tropical Asia and Africa, America, Australia and the Pacific Island (Cooke, 1958, Hooker)
Anatomical observations are fair in the family Rubiaceae, foliar anatomy and petiolar anatomy is generally overlooked in past
This paper focused endomorphic features of the petiole with a view to its utility in identification vis-a-vis taxonomy of the genus

Summary

INTRODUCTION

The genus Ixora L. (Rubiaceae) contains nearly 100 species (Hooker,1872-1897) and distributed in tropical Asia and Africa, America, Australia and the Pacific Island (Cooke, 1958, Hooker). (Rubiaceae) contains nearly 100 species (Hooker,1872-1897) and distributed in tropical Asia and Africa, America, Australia and the Pacific Island (Cooke, 1958, Hooker). They are either shrubs or small trees. The present investigators, as a part of anatomy of the family Rubiaceae, extended observations on twelve species of the said genus. Anatomical observations are fair in the family Rubiaceae, foliar anatomy and petiolar anatomy is generally overlooked in past. This paper focused endomorphic features of the petiole with a view to its utility in identification vis-a-vis taxonomy of the genus.

MATERIAL AND METHODS

Findings

DISCUSSION