Scientists decode the secrets of the hardest bean DNA in the world

UC Riverside scientists have decoded the genome of black-eyed peas, offering hope to feed the Earth's growing population, especially as the climate changes.

Understanding the genes responsible for the drought and heat tolerance of peas could eventually help make other crops more difficult as well.

Black-eyed peas are small beans with dark belly. They have been a global staple for centuries because of their environmental toughness and their exceptional nutritional qualities, such as a low protein content and low fat content. In sub-Saharan Africa, they remain the primary source of protein in the human diet.

A genome is the set of genetic codes that determine characteristics such as color, size, and disease susceptibility. All genomes contain highly repetitive DNA sequences that UCR computer professor and co-project leader Stefano Lonardi compare to "hundreds of thousands of identical puzzle pieces".

Lonardi described the process of understanding how puzzle sequences fit together as a "computation challenge." To do this, the Lonardi team has assembled the genome several times with different software tools and parameters. They then created new software capable of merging these different genomic solutions into one complete array.

With the success of this project, black-eyed pea has only joined a handful of other major crops whose genomes have been fully sequenced. The team's work on the project was published in the June issue of The journal of plants, where it has been featured as a cover, and Lonardi's free software can be downloaded online.

Research on black-eyed peas, a legume also known as cowpea, began at UC Riverside more than 40 years ago. But the presence of cowpea in Riverside is about 200 years before university.

"Cowpeas are here to help people since the early days of colonization," said Timothy Close, co-project leader, professor of botany and plant science at UCR. "It is good that we have put at the forefront of scientific research this plant so rich in local history."

This is the first high quality reference genome for cowpea.

The size of the research team is an index of the complexity of the project. Besides Close and Lonardi, María Muñoz-Amatrian, Qihua Liang, Steve Wanamaker, Sassoum Lo, Hind Alhakami, Rachid Ounit, Philip Roberts, Jansen Santos, Arsenio Ndeve and Abid Md. Additional team members from the United States came from UC Davis, the California Department of Energy's Joint Genome Institute, the New Mexico National Genomic Resource Center, and the US Department of Agriculture. United in Iowa. The members of the international team came from Finland, France, Brazil and the Czech Republic.

As in humans, there are differences between different cowpeas. Knowing which genes are responsible for qualities in individuals such as color, size or resistance to pathogens will help breeders to develop new varieties that are even more resilient to external challenges.

"Having the genome sequence helps scientists make decisions about which parent plants to cross to produce the desired offspring," said Close.

Scientists are now trying to understand cowpea as its remarkable ability to recover from drought stress.

"We are trying to understand why cowpea is so resistant to harsh conditions," said Close. "As we enter a world with less water available for agriculture, it will be important to capitalize on this capacity and develop it, using cowpea as an example to guide improvements to other vulnerable crops in the world. climate change."