Common seafood pollutants inhibit a crucial cellular defense protein.

World hazelnut production is based primarily on selections from the wild. In this study, we used 21 pairs of simple sequence repeat (SSR) primers to investigate genetic diversity in 270 clonal accessions of European hazelnut (Corylus avellana) representing a wide geographic range. Of the 270 accessions, 198 had unique fingerprints while 72 were duplicates. Based on the 198 unique accessions, the number of detected alleles per locus averaged 9.81 and observed heterozygosity (H o ) averaged 0.67. Of the 206 total alleles amplified, 20 were unique to a single accession. A genetic similarity matrix was constructed and the resulting dendrogram revealed four major geographical groups: Central European, Black Sea, English and Spanish-Italian. SSR alleles indicated the parentage of 31 accessions. The fingerprints are publicly available through the Germplasm Resources Information Network (GRIN) database. The identification of duplicate and mislabeled accessions will improve management of hazelnut genebanks, and information on genetic variation in hazelnut will assist the international research community.

A linkage map for European hazelnut (Corylus avellana L.) was constructed using random amplified polymorphic DNA (RAPD) and simple sequence repeat (SSR) markers and the 2-way pseudotestcross approach. A full-sib population of 144 seedlings from the cross OSU 252.146 x OSU 414.062 was used. RAPD markers in testcross configuration, segregating 1:1, were used to construct separate maps for each parent. Fifty additional RAPD loci were assigned to linkage groups as accessory markers whose exact location could not be determined. Markers in intercross configuration, segregating 3:1, were used to pair groups in one parent with their homologues in the other. Eleven groups were identified for each parent, corresponding to the haploid chromosome number of hazelnut (n = x = 11). Thirty of the 31 SSR loci were able to be assigned to a linkage group. The maternal map included 249 RAPD and 20 SSR markers and spanned a distance of 661 cM. The paternal map included 271 RAPD and 28 SSR markers and spanned a distance of 812 cM. The maps are quite dense, with an average of 2.6 cM between adjacent markers. The S-locus, which controls pollen-stigma incompatibility, was placed on chromosome 5S where 6 markers linked within a distance of 10 cM were identified. A locus for resistance to eastern filbert blight, caused by Anisogramma anomala, was placed on chromosome 6R for which two additional markers tightly linked to the dominant allele were identified and sequenced. These maps will serve as a starting point for future studies of the hazelnut genome, including map-based cloning of important genes. The inclusion of SSR loci on the map will make it useful in other populations.