Team:CoBRA/HumanPractices
From 2014hs.igem.org
A healthy forest is diverse. It has trees and plants of different ages, species, heights and genetic make-up. Diversity provides good quality wildlife habitat and helps limit the size and number of wildfires and insect outbreaks. In the forests of the Canadian rocky mountains,specifically the national parks, the activity of mountain pine beetle plays a role in creating forest diversity. Healthy forests are in a constant state of change in part through natural disturbances like avalanches, landslides, floods, fire and the activity of insects and diseases. Forests have evolved with these processes for thousands of years. Without them, the natural balance is lost. While mountain pine beetle are a natural part of the southern Rocky Mountain ecosystem, recent beetle outbreaks are larger than those of the past. Decades of fire suppression have created large tracts of older pine forest that provide a highway for beetle expansion. The lack of fire, combined with a recent warming trend, means that the beetles are now occurring where they haven't been observed before: farther east, farther north and at higher elevations. This is cause for concern as the mountain national parks form the margin between the beetle outbreak in British Columbia and commercial forests in Alberta. It is important to note that the beetle itself doesn’t kill the trees and that the detrimental effects associated with the mountain beetle are produced by Grosmannia Clavigera, or blue stain fungus (BSF). This fungus causes irreversible damage to the trees internal systems by converting the trees natural defenses into a carbon based food source. This clogs the various nutrient channels within the tree and the fungus uses those channels as a means to spread and eventually kill the tree. Our project will focus on building a bacterial plasmid that will produce and secrete the chitinase enzyme that will in turn be able to break down the chitin rich membranes of the BSF while leaving the tree unaffected. These genes have been cloned from interior spruce, and lodgepole pine tree, which are native to this ecosystem. Thus, the trees will be able to use their own defenses to deal with the mountain pine beetle.
As outlined in our project introduction, the coniferous forests of the great Rocky Mountains are of unparalleled importance. Not only for the sake of our economy, but also far more importantly for maintaining our local ecology and the biodiversity of these forests. Throughout this diverse forest, trees have become infected with Mountain Pine Beetles. The beetle burrows through the tree and leaves Grosmannia clavigera or blue-stain fungus in its wake. The blue-stain fungus plugs the phloem of the trees, which carries nutrients and phytochemical defenses of the tree. The trees’ main defenses are chemicals called terpenes, which the blue-stain fungus preys on. Essentially, the blue-stain fungus and the mountain pine beetle have a mutualistic relationship in which the beetle provides the fungus with a method of transport from tree to tree, and the fungus prevents the tree’s terpenes from killing the beetle. We hope if we eliminate the fungus from this relationship, we can decrease the rate at which the beetle is infesting the forests to a healthy rate.
This graphic depicts the enormity of the infestation. Historically, the beetle was killed off by the harsh winters of the Canadian Rockies, but with a series of milder winters, the beetle population has exploded exponentially, killing off the trees that provide food and habitat for most of the other organisms that live in this ecosystem.
Despite the negative effects of the beetle has always been an important part of the Rocky Mountain pine forest ecosystem, as in the past it has killed off diseased or old trees, and the beetle is a source of food to many birds such as woodpeckers and other insects. Our team does not want to completely eradicate the beetle, as this may cause additional ecological problems, but we do want to slow the beetle to the point at which it is killing trees in a sustainable manner. The best way to do this is to attack the blue stain fungus, which is a key to the beetle surviving the trees’ defence systems. Hopefully, if we eliminate the fungus, the beetles rapid expansion will be slowed to a more sustainable and healthy rate. The wood that has been infected with this fungus is usable as a building material but the rate at which these trees are being killed is unsustainable. The forestry industry cannot process all the lumber affected by the blue stain fungus, as the sheer volume of raw lumber coming in is simply too much, and as a result useable wood will be left to rot.
According to the British Columbia Forestry Department 16.3 million hectares of forest have been affected and 40 million acres have been completely destroyed, which is approximately the amount of wood harvested in ten years. Due to this damage, the supply of softwood lumber that could be harvested from the affected areas could drop between 32 and 67 percent. To combat this devastating problem, the government of British Columbia alone has already invested $884 million to mitigate the impact of the beetle. Additionally, the government of Canada has spent $340 million and is committed to spending another $800 million. Despite the government’s efforts, the Canfor Sawmill in Quesnel BC, and the West Fraser Sawmill in Houston BC, have been forced to close, resulting in the loss of 434 jobs, as their supply of softwood lumber is no longer usable. Obviously, this loss of jobs has had a devastating affect on the local economies.
http://www.vancouversun.com/Interior+sawmills+closed+beetle+epidemic+erodes+supply/9079750/story.html
http://www.pc.gc.ca/eng/docs/v-g/dpp-mpb/sec4.aspx
http://www.pc.gc.ca/eng/docs/v-g/dpp-mpb/sec3.aspx
http://www.nrcan.gc.ca/forests/insects-diseases/13381
http://www.for.gov.bc.ca/hfp/mountain_pine_beetle/
http://en.wikipedia.org/wiki/Blue_stain_fungus
http://fgya.foothillsri.ca/resource/enhanced-mountain-pine-beetle-decision-support-tool