Development of DNA Based Markers to Identify Beech Bark Disease-resistant trees in natural stands
In northern hardwood stands that have been long affected by beech bark disease, large numbers of severely deformed American beech trees persist. Stand management practices are complicated by the initiation of root sprouts by beech trees in decline due to BBD. Such sprouts can result in the formation of “thickets” of diseased, deformed beech trees of small diameter that prevent the establishment of other more desirable species yet offer little ecological or economical value. Silvicultural approaches are needed to reduce the number of susceptible trees and increase the number of resistant beech trees. Such approaches rely on the ability to distinguish between resistant and susceptible trees. One difficulty forest managers may encounter in carrying out recommended treatments is that even in heavily infested areas, trees that remain free of scale may be escapes and not truly resistant. In the initial stages of infestation, larger more mature trees are attacked first while smaller more juvenile trees do not show scale build-up until later phases of infestation. With an economical, reliable test for identifying resistant beech in natural stands, forest managers can remove susceptible trees ahead of the disease, maximizing profit by harvesting trees before they are damaged and at the same time minimize the impacts of the disease. Furthermore, such a marker can be used to enhance existing American beech breeding programs through the use of marker-aided selection.
- Develop DNA based markers to confirm parentage of full-sibling families and develop an American beech linkage map of each parent.
- Identify markers linked to resistance QTLs with potential for use in MAS (marker-aided selection).
- Develop methods to extract proteins from beech bark tissues. Perform comparative proteomic analysis to identify proteins differentially expressed between resistant and susceptible beech trees.
- Perform high-through-put cDNA sequencing, generating 180 million base pairs of sequence information
- Use sequence information to develop markers to increase density of linkage map.
- Perform genetic association tests to identify SNPs that are tightly linked to resistance and can be used to distinguish resistant individuals in natural stands. Such a marker can also be used in marker-aided selection in the ongoing beech breeding program
- Development of high-density linkage maps in American beech.
- Development of markers for us in Marker Aided Selection of resistant beech seedlings.
- Identification of markers useful in identifying resistant individuals in natural stands that can be used for carrying out silvicultural prescriptions such as maintaining resistant beech and removing susceptible beech.
Koch, Jennifer L.; Carey, David W.; Mason, Mary E. In press. Use of microsatellite markers in an American beech (Fagus grandifolia) population and paternity testing. Silvae Genetica.
Koch, Jennifer L. 2010. Beech bark disease: The oldest “new” threat to American beech in the United States. Outlooks on Pest Management 21(2):64-68, (Available online).
Koch, Jennifer L.; Carey, David W.; Mason, Mary E.; Nelson, C. Dana. 2010. Assessment of beech scale resistance in full- and half-sibling American beech families. Can. J. For. Res. 40(2):265-272.
Kubisiak, T.; Carey, D.; Burdine, C.; Koch, J. 2009. Characterization of ten EST-based microsatellite loci isolated from American beech, Fagus grandifolia Ehrh. Molecular Ecology Resources Database.
- Jennifer Koch, Research Plant Pathologist, U.S. Forest Service, Northern Research Station
- John Carlson, Director of Schatz Center for Tree Molecular Genetics, Pennsylvania State University, School of Forest Resources,
- Abdelali Barakat, Pennsylvania State University, School of Forest Resources
- David Neale, University of California at Davis, Department of Plant Sciences, Institute of Forest Genetics
- C. Dana Nelson, Southern Research Station, Southern Institute of Forest Genetics
- Tom Kubisiak, Southern Research Station, Southern Institute of Forest Genetics
Last Modified: 10/19/2010