Chapter 18 - African yam bean (Sphenostylis stenocarpa hochst ex. A. Rich) Harms)

Abstract

Lack of documentation of production statistics has deprived African yam bean of adequate awareness and utilization. African yam bean is the only cultivated, most utilized, and economically popular species of the genus Sphenostylis. Africa hosts the genetic resources and the food culture of the crop. The species has two notable and edible protein- and carbohydrate-rich products: the aerial pulse and the subterranean root tuber. It is a minor crop that holds a significant place and promises for food, medicinal, environmental, and nutritional security. The discovery of its nutritional potentials and intraspecific diversity at biochemical, genomic, and phenotypic levels are the unique successes in African yam bean research. Improved focus on the crop in research, valorization, and uses in the recent has been enhanced by these factors. However, inconsistency in tuber production by the same genotype in time and space and variation in the chromosome number: 2N ranging between 18 and 24 implicates incomplete and/or ongoing evolutionary processes in the crop. This chapter describes African yam bean, repositions some misinformation, and unveils some research gaps and way forward.