Genetic diversity in hazelnut (Corylus avellanaL.) cultivars from Black Sea countries assessed using SSR markers

Abstract

European hazelnut (Corylus avellana L.) is an important crop in Turkey, Georgia and Azerbaijan, where cultivars were selected from the native vegetation. Accessions from Turkey have been assigned to the Black Sea group, and cultivars from Georgia and Azerbaijan have a similar phenotype. Genetic diversity was investigated in 88 accessions from these three countries and compared with cultivars from Spain and Italy using 12 microsatellite loci. A high level of genetic diversity (H e = 0.71, H o = 0.70) was observed in the Black Sea accessions. Six Turkish accessions in the US hazelnut collections were found to be synonyms of cultivars in the Turkish collection in Giresun. An unweighted pair-group method using arithmetic average dendrogram and principal component analysis of 109 unique accessions showed a tendency to form subgroups by country of origin, and high diversity within each subgroup. A moderate shift in allelic frequencies (F ST = 0.114-0.131) was seen between accessions from the Black Sea and the Spanish-Italian accessions. Simple sequence repeat analysis identified the putative parents of two Turkish cultivars.

Broad-scale genetic homogeneity in natural populations of common hazel (Corylus avellana) in Ireland

“…Whilst there have been several studies on C. avellana, the present study is the first to look at natural populations of hazel using high-resolution, codominant nuclear microsatellite markers, in contrast with those which have used low resolution and/or dominant markers (allozymes and amplified fragment length polymorphisms (AFLPs)) or those which have focused on the genetics of cultivated varieties. Two allozyme studies, one of which examined populations from central to northern Europe (Persson et al 2004) and another which used samples mainly not only from Germany but also from Italy and Hungary (Leinemann et al 2013), found similar levels of genetic diversity, measured by both number of alleles (A) and expected heterozygosity (H E ) Although it is not possible to draw meaningful comparisons between levels of diversity observed in the present study with those calculated from allozymes in natural populations, it is possible to contrast these levels with those observed in cultivated varieties and landraces based on microsatellites, which were lower and ranged from H E = 0.71 to H E = 0.78 (Boccacci et al 2006;Gökirmak et al 2009;Boccacci and Botta 2010;Gürcan et al 2010b;Campa et al 2011;Boccacci et al 2013). In contrast, all but one sample analysed here had an H E >0.8 (Table 1).…”

“…All samples were genotyped for seven nuclear microsatellites (A604, A605, A613, A614, B671, B767, B791), which had previously been developed for use in European hazelnut (Gürcan et al 2010a). PCR was carried out in a total volume of 10 μl containing 100 ng genomic DNA, 5 pmol of 6-FAM-labelled M13 primer, 0.05 pmol of each M13-tailed forward primer, 5 pmol each reverse primer, 1× PCR reaction buffer, 200 μM each dNTP, 2.5 mM MgCl 2 and 0.25 U GoTaq Flexi DNA polymerase (Promega, Sunnyvale, CA, USA).…”

A multidisciplinary approach to enhance the conservation and use of hazelnut Corylus avellana L. genetic resources

“…The study of the genetic relationships and population structure among wild forms, landraces, and cultivars in a geographic area can supply information about the putative domestication events, the evolutionary relationship, or the gene flow between them. According to several authors Botta 2009, 2010;Gökirmak et al 2009;Gürcan et al 2010), C. avellana seems to have been domesticated independently in six different areas: British Islands, central Europe, Spain, Italy, Black Sea, and Iran. The results reported by Boccacci et al (2013) are in agreement with these conclusions, indicating the existence of three main germplasm groups in the Mediterranean basin which could correspond with three domestication areas: northeastern Spain (Catalonia) and southern Italy (Campania) in the West and the Black Sea region in the East.…”

“…The main result obtained from this survey was that in many collection fields are conserved the same cultivars, indicating the need to rationalize genetic resources and that few efforts were made to include new accessions in the collections. For example, the NCGR and Oregon State University have increased efforts to collect cultivated and wild accession of Corylus, such as from the Balkans, Russia and Caucasus, and now in their collections there are more than 700 accessions, including all major Corylus species (Gürcan et al 2010). However, a number of species are still lacking, especially when considering their wide geographic range, for these reasons recovering and evaluation efforts are still needed manly in Europe.…”

“…Essentially no work has been done to investigate population structure, genetic diversity, and possible genetic erosion (loss of genetic resources) of wild hazelnut. Nearly all efforts have been focused on cultivated forms largely to better understand their origin, to fingerprint germplasm accessions, and to evaluate genetic diversity Botta 2009, 2010;Boccacci et al 2006Boccacci et al , 2008Gökirmak et al 2009;Gürcan et al 2010). Recently, a first on-farm exploration was conducted on local ecotypes and on wild accessions in northern Spain (Asturias) by Ferreira et al (2010) and Campa et al (2011).…”