Oregon’s Whitebark Pine Genome Sequenced By Scientists: Threatened Trees Could Be Restored

Facing threats from climate change and white pine blister rust- a deadly fungus, mountaintop whitebark pine was recently identified as a threatened species by the federal government. Through genetic research, scientists are finding solutions to restoring the iconic whitebark pines across the West.

One particular tree- a 150-year-old whitebark pine tree in Oregon’s Deschutes National Forest was central to a study to sequence the first whitebark pine genome. By mapping out 87% of its genetic material, an old tree in Central Oregon will help to protect whitebark pine trees in the region. Scientists have sequenced the tree’s genome into a genetic map. They say this will help forest managers plant more resilient trees faster and cheaper.

With 25,362 genes within the whitebark pine’s 12 pair chromosomes, known as the tree’s genome, it is a bit like the DNA available kits for “23 and Me,” but maps out the conifer trees instead. Professor emeritus at the University of California, – David Neale, sees the whitebark pine as the poster child for restoration issues.

Leading the Whitebark Pine Genome Project, Neale explained that having the blueprint of the tree is similar to having a list of parts for a refrigerator. As with the refrigerator, it is easier to repair a thing if one understands how it was put together. Although at first sequencing was challenging- as the conifer tree genomes are 10 times larger than human genomes, whitebark pines are genomically most similar to sugar pines.

The genome of trees has previously been mapped, but the current study is a new exploration into sequencing a tree’s genome for restoration purposes, not timber harvests. The first tree sequenced was the loblolly pine, followed by sequencing of the Douglas fir, sugar pine, coastal redwood, and giant sequoia. Helping snowpack to stay in place longer, whitebark pine trees provide food for Clark’s nutcrackers, bears, and squirrels, and are important to certain Indigenous people.

Protecting the trees from blister rust has been difficult, and it currently takes about 10 years of collecting whitebark pine cones, growing seedlings, testing for rust resistance, monitoring the plants, and planting in the field to enable vulnerable trees to survive. The time and effort is expensive. The Whitebark Pine Ecosystem Foundation estimates that it costs $1,200 to $1,800 per tree. Neale confirmed that this work has been ongoing by foresters, but it is time-consuming and expensive when compared with genomic technology when it’s developed. The foundation indicated that genomic sequencing could bring the cost down to about $100 per tree.

The next step according to Neale is for scientists to sequence all types of whitebark pines, particularly those that are susceptible to blister rust and those that can stave it off, identifying genes that could help restoration efforts. To increase declining whitebark populations, around 100 seedlings of the whitebark pine tree were planted in Central Oregon early last month.

Neale is publishing a paper that is undergoing peer review, and the whitebark sequence can be found at TreeGenes- a forest tree genome database.