Researchers help unlock pine beetle's Pandora's box

(Phys.org) —Twenty researchers—more than half of them Simon Fraser University graduates and/or faculty—could become eastern Canada's knights in shining white lab coats. A paper detailing their newly created sequencing of the mountain pine beetle's (MPB) genome will be gold in the hands of scientists trying to stem the beetle's invasion into eastern forests. The journal Genome Biology has published the paper.

"We know a lot about how beetle infestations can devastate forests, just as the mountain pine beetle has been doing to B.C.'s lodgepole pines," says Christopher Keeling, the paper's lead author.

The SFU graduate, now a research associate in Joerg Bohlmann's Lab at the University of British Columbia's Michael Smith Laboratories, says: "It's the beetle's genome that will help us figure out exactly how it does its damage and hopefully stop it."

The genome reveals large variations among individuals in the MPB species—about four times greater than the variation among humans.

"As the beetles' range expands and as they head into jack pine forests where the defensive compounds may be different, this variation could allow them to be more successful in new environments," explains Keeling.

Eastern Canadians are bracing for the B.C. MPB's threat to appear in Ontario, Quebec and Maritime forests during the next two decades. The rice grain-sized insect has already wiped out an area of B.C. lodgepole pine forest five times larger than the size of Vancouver Island. It is becoming the scourge of Alberta's forests and is headed for Saskatchewan.

"The MPB genome allows us to examine the population differences for beetles at various parts of an outbreak. For example, we can find out whether the ones heading east are well-adapted to their new host and environment," says Steven Jones, an SFU molecular biology and biochemistry professor and SFU graduate.

"Information like this can help the scientists who model an outbreak, which then informs policymakers who must decide where to best put a province's resources to mitigate further damage."

The genome sequencing of the first North American pest bark beetle species in the genus Dendroctonus also uncovers a bacterial gene that has jumped into the MPB genome. This gene codes for an enzyme that digests sugar.

"It might be used to digest woody tissue and/or micro-organisms that grow in the beetle's tunnels beneath the bark of a tree," explains Keeling. "Gene transfers sometimes make organisms more successful in their environments."