Scientists have produced the first chromosome-scale genome assembly of the white oak (Quercus alba), an abundant forest tree species across eastern North America that is ecologically, culturally, and economically important.
The Quercus alba individual sequenced for the genome assembly, growing at Star Hill Farm, Loretto, , Kentucky, the United States. Image credit: D. Larson.
“Oaks are important members of ecosystems throughout much of the world,” said University of Tennessee researcher Meg Staton and colleagues.
“In eastern North America, the white oak is a keystone species and is one of the most abundant forest trees across much of its range.”
“In addition to its ecological and cultural importance, white oak has significant economic importance, including a number of high-value timber applications and as the primary species used to cooper barrels for aging distilled spirits.”
“However, few studies have addressed the genomic diversity of the white oak, and a lack of available genetic and genomic resources currently presents barriers to furthering the understanding of white oak biology and evolutionary history.”
In their research, the authors sequenced the genome of an individual of the white oak from a forest near Loretto, Kentucky, the United States.
They found that this oak species has high genetic diversity, much of which predates its divergence from other oaks and likely impacts divergence time estimations.
“The white oak genome represents a major new resource for studying genome diversity and evolution in Quercus,” Dr. Staton said.
“Also, unbiased gene annotation is key to accurately assessing R (disease resistance) gene evolution in Quercus.”
“Our paper addresses the extent of the genetic diversity and population differentiation in the white oak, and how gene content and disease resistance genes appear to have evolved during the history of Quercus and related species.”
The authors note that the amount of standing genetic variation and the extent to which populations are locally adapted will have implications for the response of the white oak and other oak species to increasingly prevalent heat and drought stress.
“The details are of interest to those invested in the sustainability of white oak across economic, ecological and cultural boundaries,” they said.
The study was published in the journal New Phytologist.
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Drew A. Larson et al. A haplotype-resolved reference genome of Quercus alba sheds light on the evolutionary history of oaks. New Phytologist, published online February 11, 2025; doi: 10.1111/nph.20463
