LEAF AND STEM ANATOMY OF FOUR DIOSCOREA SPECIES D. ROTUNDATA (Poir), D. ALATA (L), D. BULBIFERA (L) AND D. DUMETERUM (Kunth)

ABSTRACT 

The edible tubers from different species of Dioscorea are a major source of food and nutrition for millions of people in the world. The anatomy of the organs (leaves and stems) of Dioscorea rotundata, Dioscorea bulbifera, Dioscorea dumeterum and Dioscorea alata were examined and compared with the aim of identifying or delimiting the existing characters between these species. Anatomical studies were carried out on the leaves and stems of the four species. The result obtained from this investigation showed features of anatomical importance in the leaves and stems of these species. Results from epidermal cells showed differences in the shapes and sizes of the epidermal cell walls. The result from the investigation has proved that the leaf and stem anatomy of the four dioscorea spp exhibits characters like trichomes, spindle, nail, curve-straight appearance in shapes and the presence of stomata on the lower epidermis layer of the leaf, while stomata were absence in the upper epidermis (hypostomatic) in nature. This could be included with other reliable attribute of this species in an attempt to fashion out an authentic classification among the varieties of Dioscoreae. This observation will be useful and contribute to the further classification of Dioscorea species. 

TABLE OF CONTENTS 

Title page ﾿ i

Certification ﾿ ii

Declaration ﾿ iii

Dedication ﾿ iv

Acknowledgments ﾿ v

Table of contents ﾿ vi

List of tables ﾿ vii

List of figures ﾿ viii

Abstract 

CHAPTER ONE 

1.0  INTRODUCTION ﾿ 1

1.2 ﾿ Justification ﾿ 2

1.3 ﾿ Aims and Objectives ﾿ 3

CHAPTER TWO

2.0 ﾿ LITERATURE REVIEW ﾿ 4

2.1 ﾿ D. bulbifera ﾿ 4

2.2 ﾿ D. alata ﾿ 6

2.3 ﾿ Description of one out of the four species of Dioscorea ﾿ 8

2.4 ﾿ Anatomy and Plant Classification ﾿ 11

CHAPTER THREE

3.0 ﾿ MATERIALS AND METHOD ﾿ 13

3.1 ﾿ Collection and Identification of Plant Materials ﾿ 13

3.2 ﾿ Anatomical Studies ﾿ 13

3.3 ﾿ Epidermal Studies ﾿ 14

3.4 ﾿ Photomicrograph ﾿ 14

CHAPTER FOUR

RESULTS ﾿ 15

CHAPTER FIVE

5.1 ﾿ Discussion ﾿ 17

5.2 ﾿ Conclusion ﾿ 18

REFERENCES ﾿ 19

APPENDIX