Studies of Fish and Forests Help Maintain Diversity
College of Natural Resources researchers have played a key role in understanding and maintaining the genetic diversity of our fisheries and forest resources. The genetic modifications science is now capable of are tempered by an increasingly global debate over what scientists should do. We know we can make fish grow faster, which could help the fishing industry and hungry people in developing countries. But how would that change the world's native fish populations? Faster growing fish may outcompete native populations for food and mating partners. If they reproduce, evolution of a species may be altered when unanticipated characteristics dominate, leading to changes in territoriality, seasonal migrations, and prey. Changes in enough individuals could alter the species' traditional ecological niche.
University of Minnesota fisheries scientists were among the first to take a proactive approach to questions of risk, asserting that protocols for containment of altered fish, for instance, should be addressed up-front in the scientific process. This work led to development of the nation's first set of guidelines to assess and manage environmental risks of genetically modified fish, and now plays a prominent role in creating international standards.
With tree geneticists, fast growth was the major goal through much of the last century, while recent interest lies in tree form, disease resistance, and fiber characteristics.
The longevity of trees makes for interesting science. Growth records, some now 100 years old, are fundamental to research. For example, selection of white pines resistant to blister rust disease began in the '20s and continues today with new tools and much more rapid progress. Fundamental work is ongoing; such as, how far seeds can be moved from the climate in which they were produced and still thrive, which form and growth characteristics are the result of inheritance and which are shaped by environment, and which genes control certain plant characteristics.
Sea Lamprey and Pheromones
The eel-like sea lamprey attaches to a host fish, bores a hole, and removes the fish's bodily fluids. In some regions of the Great Lakes, sea lampreys consume more fish than commercial and sport fishing combined. U of M scientists are world leaders in understanding pheromones, chemicals the lampreys use to communicate with each other. Detected by the olfactory sense, they stimulate specific instinctual migratory and spawning behaviors; manipulation of pheromones could lead to biological control of this and other nuisance species. Electrodes placed onto the olfactory surfaces of fish, including sea lampreys, monitor olfactory responses to pheromone blends. Behavioral tests have already shown the identified compounds to be active at a gram per 10 billion gallons (10,000 Olympic-size swimming pools).
Researchers are now in the process of obtaining licenses from the Environmental Protection Agency so they can test whether it might be feasible to lure lampreys into traps or into an unsuitable habitat where their eggs won't survive.
Blister-Rust Disease Resistance
Pines are relatively new to Minnesota's post-glacial landscape. White pine (cones shown) moved in from the east 2,700 years ago and were joined by red pine (seedlings shown) 1,000 years ago. In 1913, a major threat to white pine appeared: blister-rust disease. University research efforts have focused on identifying natural genetic resistance to the disease and understanding the conditions that limit its spread.
Minnesota Tree Improvement Cooperative
The Minnesota Tree Improvement Cooperative, a unique public/private collaboration of 30 members, was formed in 1981 to apply traditional genetic techniques to increase the quantity and quality of timber yields in the region by selecting and breeding trees that grow faster, have better form, and are more disease resistant. Certification ensures that the highest quality conifer seedlings are used to reforest public lands, informs private landowners of the geographic origin of seedlings they plant, and helps foresters understand the genetic consequences of their management activities. The Cooperative has bred white spruce that will grow 25 percent faster than wild trees.
Aspen/Larch Genetics Cooperative
The regional Aspen/Larch Genetics Cooperative at the University's North Central Research and Outreach Center in Grand Rapids gives scientists the opportunity to improve hybrid, aspen, and larch seed production; and plantation establishment techniques. Long-term genetic research with aspen and aspen hybrids has shown gains of nearly 35% in height and more than 100% in volume growth. Ongoing work with larch species centers on seed selection to enhance adaptation and promote rapid growth.
Microsatellite DNA Markers
U of M fisheries scientists developed the first microsatellite DNA markers for northern pike and walleye, enabling researchers to track single fish and families of origin by identifying the genes in a microscopic bit of skin attached to a fish scale.
Researchers used the DNA analysis to compare survival of stocked walleye from two different sources. The findings will help guide state, federal, and tribal fisheries managers in their stocking programs.
Raising Concern for Native Fish
University of Minnesota fisheries research has identified potential environmental impacts of releasing genetically engineered fish into natural waterways. Faster growing fish may outcompete native populations for food and mating partners. If they reproduce, evolution of a species may be altered when unanticipated characteristics dominate, leading to changes in territoriality, seasonal migrations, and prey. Changes in enough individuals could alter the species' traditional ecological niche.