Development of Improved Mycorrhizal Fungi for Use in Reforestation and Reclamation of Mined Lands
Forest lands that have been used for coal are difficult to return to a forested state. Reclaimed mine sites are chemically, physically, and biologically altered and often lack the necessary quality and quantity of mycorrhizal fungi to sustain a plant community. Mycorrhizal fungi play an important role in reforestation by providing the plant several benefits that are critical for its survival and growth in a nutrient-poor and water-deficient environment. Therefore, these fungi will have to be reintroduced into the environment for reforestation to be successful. In addition, newer and improved strains of fungi may be necessary initially to combat and remedy the harmful effects of pollution before the once indigenous strains can take hold in the affected regions.
There is a lack of basic biochemical knowledge describing the factors that contribute towards successful symbiosis and, therefore, the success of reforestation through mycorrhizal phenomenon. Very often, using mycorrhizal fungi is a trial and error process because knowledge of relationships of soil conditions and tree/fungus interactions has not been worked out. Biochemical markers linking soil chemistry and individual/group of fungi that will be compatible under those conditions will help in determining the most suitable group of fungi for a certain region. Our work on identification of symbiosis-specific genes that can be used for monitoring formation, development, and functioning of ectomycorrhizae will be useful in identifying and better predicting the tree-fungus combinations that would work under specific conditions. This would significantly improve the success rate by minimizing the traditional trial and error.
We are testing several known mycorrhizal fungi for their ability and efficacy to support survival and growth of seedlings planted in reclaimed sites. Every year we have been generating Virginia pine seedlings inoculated with various fungi and planting them in reclaimed abandoned mine site locations in Ohio. Qualitative and quantitative measurements are being made to assess fungi that aid survival and growth of seedlings. Investigations are also carried out to ascertain the presence of inoculated fungi as well as any changes that happen due to competition from existing fungi in those locations. In addition, we have also been isolating novel fungi present in such sites and conducting research to identify and use them in larger scale. The fact that they have survived the harsh conditions makes them ideal candidates for use in such suboptimal conditions. We use molecular methods such as restriction fragment length polymorphism restriction fragment length polymorphism (RFLP) analyses and transmission electron microscopy for identifying of these fungi because these are precise for both qualitative and quantitative analyses of the mycorrhizal associations. We have also been conducting fundamental research on mycorrhizal symbiosis at the biochemical and molecular levels.
Evaluation of existing mychorriziae and identification of novel mychorrhizae will lead to improved reclamation and reforestation of mined spoils and badlands. The biochemical/molecular work will be helpful in future for genetically improving mycorrhizal fungi that can be adapted for handling a variety of problems associated with plant health causing forest decline and decrease in biomass.
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- Shiv Hiremath, Research Biologist, U.S. Forest Service, Northern Research Station
- Leila Pinchot, Research Ecologist, U.S. Forest Service, Northern Research Station
- John Sprouse, Director, Ohio State Dept. of Natural Resources
- Division of Mining & Reclamation, Cambridge, Ohio
- Phil Perry, Wayne National Forest, Nelsonville, Ohio
- Gary Willison, Wayne National Forest, Nelsonville, Ohio
Last Modified: 12/05/2016