Biodiversity and Domestication of Yams in West Africa

Acknowledgements
Foreword

Introduction

The Dioscorea rotundata Poir. yam

Botanical aspects
Geographical distribution
Botanical origins of Dioscorea rotundata
Organization of diversity in Dioscorea rotundata
. Yam diversity on African farms
. State of the scientific knowledge
  Morphological and physiological diversity
  Genetic diversity
  Chemical diversity
  Cooking quality
  Sexual features
  Cultivation requirements
  Intrinsic productivity of the plant material
  Market adaptation

Wild yams Dioscorea praehensilis Benth and Dioscorea abyssinica Hochst ex Kunth

General
Dioscorea praehensilis
Dioscorea abyssinica
Addendum: Dioscorea togoensis Knuth

Phenomena that could explain the variability of wildand domesticated yams

Climatic disturbance
Anthropogenic pressure
Reciprocal gene flow between wild and cultivated yams
Effects of periodic fallows
Variations in genome expression
Mutation
Ploidization

Domestication leading to Dioscorea rotundata

Definitions and general aspects
Rationales and limits of domestication
. Significance and importance of domestication for farmers
. Framework of domestication

Cultivation techniques used to transform wild yams into double-harvest Dioscorea rotundata yams

General
Domestication process and effects
Thoughts on domestication leading to double-harvest Dioscorea rotundata yams

Conclusion

Glossary of technical terms

References