Regeneration in the Face of Adversity: The Emergence of Ash Trees More Resistant to Dieback Disease
In a groundbreaking study, scientists at the Royal Botanic Gardens, Kew, and Queen Mary University of London have discovered that a new generation of ash trees is evolving genetically to become more resistant to ash dieback.
## The Evolutionary Process
The research, published in the prestigious journal Science, reveals that natural selection is actively shaping the evolution of resistance within the ash tree population. This process is aided by the high mortality rate among young ash trees exposed to the fungus early in their development, ensuring that only those with some level of resistance survive to reproduce.
Researchers identified thousands of genetic variations (mutations) across the ash tree genome that are associated with resistance to ash dieback. These variations are more common in younger trees than in older ones, indicating a shift in the genetic makeup of the population over time.
The study supports the theory of polygenic evolution, where multiple genes contribute to a single trait—in this case, resistance to ash dieback. This is a long-standing prediction of Darwinian theory, now observed in a real-world context.
By comparing the DNA of ash trees that predated the ash dieback outbreak with those that have grown since, scientists observed subtle shifts in the frequencies of DNA variants associated with tree health. These shifts suggest that younger trees possess greater resistance to the disease.
## Hope for the Future
The findings offer a huge amount of hope for the future of the ash tree species. While previous predictions suggested that up to 85% of UK ash trees could succumb to the disease, the evolution of resistance in younger generations may mitigate this outcome. However, no complete immunity has been observed, and ongoing research is crucial to understand the dynamics of this resistance fully.
## Funding and Collaboration
The study was undertaken at the Woodland Trust's Marden Park wood in Surrey, and was funded by Defra, which has invested more than £9 million in ash dieback-related research since 2012.
The development offers a beacon of hope in the fight against ash dieback, a disease caused by the fungus Hymenoscyphus fraxineus, which first arrived in Britain in 2012 and has since spread rampantly across the countryside.
Annunciata Elwes, the writer of this article, has been a long-time collaborator with our platform, her work winning the Property Magazine of the Year Award in 2022. Aside from her journalistic pursuits, Annunciata is also a co-founder of a literary, art, and music festival and a director of TIN MAN ART, a contemporary art gallery founded in 2021 by her husband, James Elwes.
The article is published by our platform.
[1] Dr. Carey Metheringham, et al., "Genome-wide evidence for adaptive evolution in ash trees in response to ash dieback disease," Science (2023). [2] Defra, "Ash dieback: research and development," available at: https://www.gov.uk/government/collections/ash-dieback-research-and-development [3] Woodland Trust, "Marden Park wood," available at: https://www.woodlandtrust.org.uk/visiting-woods/woods/marden-park-wood/ [4] Forest Research, "Ash dieback: the disease and its impacts," available at: https://www.forestresearch.gov.uk/tools-and-resources/ash-dieback/ash-dieback-the-disease-and-its-impacts/
In this evolutionary process, the high mortality rate among young ash trees due to ash dieback allows for natural selection to shape the emergence of resistance within the ash tree population. Researchers have discovered multiple genetic variations associated with resistance to ash dieback, which are more common in younger trees, indicating an evolution towards health-and-wellness and environmental-science survival.
The groundbreaking study published in Science supports the theory of polygenic evolution, suggesting that multiple genes contribute to the development of resistance to ash dieback, offering hope for the future of the ash tree species and potential solutions against climate-change pressures.
