Genomics is behind an innovative new method for breeding trees that can adapt to our changing world
As global temperatures rise, some scientists believe that the key to helping plants and animals survive is locked in their genetic code.
Genes determine everything from how an organism looks to how it responds to heat and cold. Studying the function and relationships of genes – an area of research called genomics – may reveal which individuals in a species are best able to cope with a changing environment.
“[We can] look at the entire DNA information collectively and use the information to identify the superior individuals,” said Prof. Yousry El-Kassaby, head of UBC’s Department of Forest Resources Management.
This strategy could be especially important for plants, since they cannot simply pick up and move when the conditions around them become too challenging.
Adapt or die
El-Kassaby has developed a new plant-breeding project that could give trees a helping hand in the adaptation race.
“Trees, in their present location, are here because they’re adapted to this location,” he said. “When the climate changes, this area is expected to be warmer, thus not suitable anymore. The tree that is more flexible, more resilient, the greater the chances it will survive. If not, it’s going to die.”
Some tree species are expanding their ranges further north, El-Kassaby points out. But he thinks that process is too slow.
“There is a mismatch between the migration through pollen and seed and the speed of climate change,” he said. “The migration of plants is not fast enough.”
El-Kassaby’s idea is to study the DNA of trees at the northern edge of their ranges and pinpoint the individuals with genes that make them best suited to that new environment. Trees existing at the species’ northern ranges are exposed to an onslaught of extreme environmental conditions and ones that survive and thrive have proven their resilience. Breeders can then select those trees and plant their offspring along that front edge of the population.
There are a number of genetic qualities that make a tree more resilient to climate change, says El-Kassaby.
“You want to make sure these trees in the forest are not vulnerable to insects or disease, grow fast and are adapted to extreme environmental conditions like cold temperature and drought,” he said.
Identifying superior trees
So how can breeders figure out which trees have the genetic qualities to help them cope with climate change?
El-Kassaby’s program starts by finding the healthiest, strongest trees at the very edge of the species range. However, a tree that looks healthy does not necessarily have good genes. Individuals that happen to be growing on a fertile patch of soil may grow better than trees that are genetically stronger, but are growing on rocky ground with little sunlight.
This is where El-Kassaby’s idea comes into play. Once these trees are identified, they are DNA fingerprinted for tens or even hundreds of thousands of DNA markers known as Single Nucleotide Polymorphism (SNPs). The information is then used to compare the selected trees and identify the best ones for use as parents for seed production. The seeds are then planted back in the natural forest to grow into adapted seedlings.
The project is innovative because it allows breeders to settle on the best trees very quickly, says El-Kassaby.
Traditional breeding programs require a complicated scheme for crossing different trees so that breeders can track the parents of each seedling. This process is cumbersome and can take years. But when it comes to dealing with climate change, time is of the essence. El-Kassaby says his program is efficient and allows breeders to test thousands of trees at their natural setting and at once.
Scientists are just starting to use genetic information to fight the threat of climate change in forests, says El-Kassaby. But he thinks the potential is enormous.
“The major challenge is our lack of understanding of the massive genomic information we are generating,” he said. “We are at the start of a long and difficult road.”
Three other UBC projects focus on adapting to climate change
UBC News received three related submissions describing exciting new work being conducted by UBC researchers to advance our understanding of how to adapt our world for climate change.
UBC scientist Adriana Suarez-Gonzalez is studying the genes of poplar trees, a species that grows from California to Alaska, to understand how the trees adapt in a bid to optimize breeding and conservation strategies.
Master’s student Shannon May-McNally is taking a close look at the DNA of two closely related Alaskan fish. She wants to understand how small differences between habitats can influence early evolution, and may help predict how climate change will affect native fish.
Doctoral student Natalie Sopinka says understanding how fast an animal’s heart beats may help save it from extinction. In the growing field of conservation physiology, scientists are developing novel conservation strategies that incorporate an animal or plant’s physiology, which is key to understanding how they will cope with stressors like climate change.