Study Helps Map Path to Improved Cassava Production

by Robert Sanders (UC Berkeley/Ethanol Producer Magazine) A new analysis of the genetic diversity of cassava will help improve strategies for breeding disease resistance and climate tolerance into the root crop, a staple and major source of calories for a billion people worldwide.

Published online April 18 in Nature Biotechnology, the UC Berkeley-led project involved scientists from the U.S. Department of Energy Joint Genome Institute and institutes in Africa, Australia, the United States and the Pacific Islands.

In the paper, the team, led by Daniel Rokhsar, a UC Berkeley professor of molecular and cell biology and of physics, compared the cassava reference genome to the genomes of its relatives: the castor bean, rubber tree, Ceara rubber and 53 cultivated and wild cassava varieties from around the world.

They were able to detect the genetic signature of past cassava improvement programs going back to the 1930s, which interbred cassava and Ceara rubber, and the persistence of these Ceara rubber regions in elite cassava varieties suggests they confer desirable traits.

They also mapped out how the many cultivated cassava varieties are related, which can help breeders maximize genetic diversity in improvement programs.

The root crop also represents a strategic source of renewable energy—as biomass from which ethanol is being produced for transportation fuels. With the help of genomics, researchers hope to apply advanced breeding strategies that can improve cassava’s resistance to diseases and improve crop yields, Rokhsar said. READ MORE and MORE (Joint Genome Institute) and MORE (Monash University)