Diversity in the Stem Anatomy and Tissues of Several Species of Annona (Annonaceae) in Nigeria

Abstract

Comparative study of the stem anatomy of Annona trees was carried out to facilitate identification of taxa when their reproductive parts are not available. Stem specimens of four out of the five species categorized as important under-utilized species were collected and subjected to anatomical studies. Macerated materials followed Schutze's method of maceration and the transverse sections of the stem were cut using Reichert Sledge Microtome. Intrageneric characters observed are: epidermal layer uniseriate with round, oval to polygonal collenchyma cells. Wood is diffuse-porous, vessel elements are diffuse, vessels are of two types, that is, short/wide with simple pits and long/narrow with bordered pits. Diagnostic characters for the identification of each of the species are also reported.