A new study has revealed that genetically identical forest trees raised in different environments react differently when exposed to drought conditions.
This so-called ‘nursery effect’ has been noted in anecdotal fashion by foresters and gardeners for some time but has not undergone scientific study until now. In the study, the scientific team took identical clones of three widely grown varieties of poplar tree raised in 3 areas of Canada with markedly different climates. When these trees (which require sizeable volumes of water) were subjected to drought conditions older trees from drier areas fared better than their counterparts.
A question of time
The study suggests that time plays an important part in the trees ability to respond to changes in their environment. Professor Malcolm Campbell, co-author of the study, suggests that these finding match results of studies on human gene activity over time.
“Spanish research showed that very young twins (three-year-olds) showed no difference in the way their genes responded. But as they looked at older and older twins such as 50-year-olds, they had divergent patterns of gene activity. If the individuals were brought up in different environments (for example being put up for adoption) then the patterns of divergence was even more marked.”
Professor Campbell believes this study could lead to interesting future research into the possibility of ‘training’ varieties of tree to become more drought resistant: “You might be able to find the means in which to create conditions that will train the genome so then it will be better suited for whatever environmental conditions are further down the line.”
Around 2 billion people live in dryland areas and many rely on forests for their livelihoods. Trees that can adapt readily to environmental change are likely to become increasingly vital, particularly with a burgeoning human population (tipped to hit 7 billion this year) coupled with increasing levels of desertification.