American Beech Bark Disease Genome Project
The American Beech tree (Fagus grandifolia Ehrh.), native to eastern North America has ecological importance and provides high quality hardwood for wood products. This species is currently susceptible to beech bark disease (BBD) and it is facing considerable rates of mortality in North America. The disease occurs from an interaction between woolly beech scale insect (Cryptococcus fagisuga) and one of two species of the fungus Nectria (N. coccinea or N. galligena).
The final EST sequence database originated from two transcriptome assemblies generated at John Carlson’s lab at Penn State University (see resources) will be used as SNPs source for genotyping in association study. To gain insights into the molecular mechanisms underlying disease resistance in F. grandifolia, RNA samples were sequenced by using the Roche 454 short reads sequencing platform when RNA was isolated from both disease-resistant and disease-susceptible trees.
The project aims to determine genetic architecture of disease resistance in American Beech and describe patterns of genetic and phenotypic variation. The question of interest in our study would be are the alleles or genotypes at a genetic marker associated with disease status? We will use statistical methods to test associations between SNPs and phenotypes. Here we will apply approach to associate variation of 512 full sib progeny to ~20K high confidence SNPs and identify candidate genes for resistance that contain polymorphisms reported to be associated with Beech Bark Disease (BBD).