EDMONTON — University of Alberta researchers say a pine tree's own chemistry could help in the fight against the damaging mountain pine beetle.
Researchers led by Rashad Zaman, who is working towards a PhD in forest biology and management, analyzed the impact of various fungal infections on the trees' chemical defence.
The team took samples of the vascular tissue from lodgepole pines infected with two of the most common fungal diseases affecting trees in western Canada: Atropellis canker and western gall rust. They also infected mature lodgepole pines with three mutually beneficial fungi of the mountain pine beetle. After a few weeks, the chemical profiles were compared with those from healthy trees.
The results suggest the three symbiotic fungal species and the western gall rust made the trees more vulnerable to infestation because they reduced a tree's ability to defend itself.
On the other hand, the pathogen causing the canker increased a tree's defences against mountain pine beetles.
According to Zaman, who works under the supervision of U of A forest entomologist Nadir Erbilgin, one of the co-authors on the study, the findings show the value of using the emerging approach of metabolomics — the tree's own chemistry — as a diagnostic tool. It also gives researchers information long before an attack, which is crucial to lessening the trees' susceptibility to pest invasion.
"If we can detect the trees in the early stages of infection in a forest, management practices can prevent the spread of the infection by measures such as using insect traps and harvesting healthy trees to avoid spread, or by burning infected trees," Zaman adds.
The findings represent a stepping stone for further research aimed at breeding the trees to be more resistant to disease-causing fungi and pests like mountain pine beetles.
Researchers also developed a potential monitoring tool through the study, by baiting insect traps with the chemical compounds taken from trees infected by each of the five fungal pathogens. Once hung in the forest, Zaman hopes the traps can show which of the terpenes attracted or repelled mountain pine beetles.
More information can be found here. To speak with one of the researchers, please contact: Sarah Vernon | University of Alberta communications associate | svernon@ualberta.ca