Figure: Two wild ancestors—Arachis ipaensis (left) and Arachis duranensis (right)—of the cultivated peanut. Photo by Merritt Melancon/University of Georgia.

Better resistance to pests and improved tolerance to drought are just some of the possible benefits of the USDA Agricultural Research Service (ARS) initiative that successfully produced the clearest illustration yet of the complex genomic history of the cultivated peanut (Arachis hypogaea).

The USDA scientists and collaborators conducted the project to elucidate the molecular and cellular mechanisms that define the growth and development of a peanut plant, including the expression of desirable characteristics such as high seed yield, enhanced oil quality, and resistance to diseases.

In 2006, the researchers reported the successful sequencing of two wild peanut ancestors separately. In their recent study, they used advanced DNA sequencing equipment and sequences the two merged genomes in a single commercially grown peanut to get the missing information they missed in the previous study. The researchers also tried to recreate this genomic merger by crossing two ancient peanut species and analyzed the results in 7 generations of offsprings. The findings showed a fascinating trend of DNA switching and deletions that took place in the offsprings, which might be the cause of diversity in seed size, shape, color, and other characteristics of the current cultivated peanuts.

Read more results from USDA ARS.