Chapter 4 - Dioscorea trifida L.f.: a little known South American species

Abstract

Most cultivated plants have been extensively studied. However, tropical starchy crops, such as yam, have been largely neglected, as the species native to South America is Dioscorea trifida. Known mainly as “cush-cush,” among several other popular names, the species was domesticated by the indigenous peoples who inhabited the border between Brazil, Guyana, Suriname, and French Guiana. Its tubers are considered caloric, with antimicrobial and diuretic properties. Currently, it is cultivated by traditional communities and family farmers, with limited commercial production. However, the socioeconomic pressures suffered by these communities in the countries of South America over the last decades, as well as the introduction of yam species native from other continents, mainly Dioscorea alata and Dioscorea cayenensis, have led to a decrease in the cultivation and consumption of the American species, also causing the loss of their genetic diversity. Of the American edible species, D. trifida deserves special attention, as it is the only domesticated yam still used, with culinary and agromorphological characteristics capable of competing with the best Asian and African yams. This chapter presents an overview of D. trifida, highlighting its botanical, evolutionary, agronomic, economic, nutritional, and genetic aspects.