Genetic markers identify the sex of yams and accelerate breeding

Researchers have identified the genetic markers that distinguish the sex of yam plants, saving time and resources for future breeding efforts.

White Guinea yam (Dioscorea rotundata) is native to West Africa, where it has been a food security crop for centuries. As Africa is rapidly urbanizing, yams are now being grown commercially. This labor-intensive crop provides a source of rural employment. The large tubers are traded in open air, city markets and are increasingly sold as prepared food, such as ‘pounded yam’ in popular, moderately-priced restaurants.

However, productive yam cultivation is constrained by various pests and diseases and by the lack of improved varieties. Yam has been an orphan crop with progress in breeding limited by a lack of genetic and genomic tools. This may be about to change. For the first time, researchers have sequenced the genome of the white Guinea yam, the most important food yam in West Africa. Using the sequence information, and characterizing lines segregating for different traits, the team identified genetic markers, including those for the sex of the yam, which has male and female flowers on separate plants. The markers will allow plant breeders to separate male from female plants at the seedling stage, greatly improving the efficiency of planning and carrying out crosses in breeding programs.

Continue reading the story in the RTB 2017 Annual Report: From science to scaling.