Faba bean (Vicia faba L.) is an important food and feed legume because of the nutritional value of its seed protein and starch content, good biomass, and high efficiency nitrogen fixation. This study analyzed the molecular genetic diversity and population structure of 101 Turkish faba bean accessions using simple sequence repeat (SSR) markers. A total of 32 SSR markers yielded 281 loci of which 277 (98.6%) were polymorphic. Mean dissimilarity between genotypes was 0.355, a relatively high value which was expected given faba bean’s large genome and limited breeding history. According to the results, faba bean individuals grouped into three main clusters based on both distance matrix (neighbor-joining algorithm) and model-based (population structure) clustering analyses. Clustering was not correlated with seed size or origin within Turkey. Six cultivars were included in the analysis and showed high genetic diversity compared with the landraces, as expected, given the fact that at least some of the cultivars were bred by hybridization. A total of 47 individuals were selected for the core collection to represent the diversity of Turkish faba bean germplasm. This core set encompasses material adapted to all growing regions and should be a priority for morphological characterization.
Şurhan Göl, Sami Doğanlar, and Anne Frary
Anne Frary, M. Ali Keçeli, Bilal Ökmen, Hasan Ö. Şιğva, Ahmet Yemenicioğlu, and Sami Doğanlar
In this work, 29 pepper cultivars that represent the diversity of types and varieties grown in Turkey were analyzed for water-soluble antioxidant capacity and phenolic and vitamin C contents. In addition, 14 non-Turkish cultivars were tested for comparison. Significant diversity was observed in the different cultivars with the most variation (7.4-fold) seen for total antioxidant capacity, which ranged from 2.57 to 18.96 mmol Trolox/kg. Vitamin C content for the peppers ranged from 522 to 1631 mg·kg−1, a 3.1-fold difference, whereas total phenolic content for the pepper cultivars ranged from 607 to 2724 mg·kg−1, a 4.5-fold difference. When cultivars were grouped by morphology/use, it was found that some types had significantly more variation and higher antioxidant activities than other types. Thus, for water-soluble antioxidant capacity, most variation was seen in long, blunt-ended Çarliston types, whereas long, pointed Sivri peppers had the highest mean capacity. Bell-shaped Dolmalιk and Sivri peppers had the most variation for phenolic content, but fancy Süs and Sivri types had the highest means for this trait. Dolmalιk types showed the most variation for vitamin C content, whereas Süs and Sivri peppers had the highest means for this character. All three parameters were significantly and positively correlated with the strongest correlation between total antioxidant capacity and phenolic content (r = 0.71). The presence of significant variation for antioxidant content in Turkish germplasm indicates that this material can be used for improvement and genetic mapping of nutritional content in pepper.
Oğuz Top, Cantuğ Bar, Bilal Ökmen, Duygu Yüce Özer, Dane Rusçuklu, Nilüfer Tamer, Anne Frary, and Sami Doğanlar
Wild tomato species have been widely used for improvement of tomato disease resistance but have not been extensively explored for health-related traits. In this work, three interspecific populations derived from backcrosses between cultivated tomato and Solanum pimpinellifolium (LA1589), S. habrochaites (LA1223), and S. peruvianum (LA2172) were analyzed for water-soluble antioxidant activity, phenolic content, vitamin C content, and basic agronomic traits including fruit weight, shape, and color. The wild species accessions significantly exceeded S. lycopersicum for all three antioxidant traits with only one exception: vitamin C content in S. habrochaites LA1223. Several populations and traits showed transgressive segregation indicating that the backcross populations contained individuals with allele combinations that allowed antioxidant activity/content to exceed that of both parents. The S. habrochaites LA1223 population provided the best starting material for improvement of water-soluble antioxidant activity and phenolics content with 20% and 15% of the population, respectively, significantly exceeding the parental values for these traits. Moreover, the S. habrochaites population contained individuals that had nearly 2-fold more water-soluble antioxidant activity and phenolic content than cultivated tomato. The S. peruvianum LA2172 population was best for improvement of vitamin C content with 3-fold variation for the trait and individuals, which had twice as much vitamin C as cultivated tomato.
Anne Frary, Hasan Özgür Şığva, Ayfer Tan, Tuncer Taşkın, Abdullah İnal, Sevgi Mutlu, Mehmet Haytaoğlu, and Sami Doğanlar
Turkey is a secondary center of diversity for melon (Cucumis melo) and is home to a variety of regional morphotypes. This diversity is housed in a national germplasm repository with more than 500 accessions. Molecular genetic variability of 209 melon genotypes from 115 accessions of this collection was characterized using amplified fragment length polymorphisms (AFLPs). Ten AFLP primer combinations yielded 279 reproducible fragments, which were used for dendrogram and principal coordinate analyses. These analyses showed two major clusters of Turkish melons: one group contained highly similar genotypes (maximum Dice dissimilarity coefficient of 0.18), whereas the other group was genetically more diverse (maximum dissimilarity 0.41). Although average dissimilarity was low (0.13), a broad range of genetic diversity was observed in the collection. A marker allele richness strategy was used to select a core set of 20 genotypes representing the allelic diversity of the AFLP data. The core set had double the average diversity (0.26) of the entire set and represented the major morphotypes present in the collection. Molecular genetic diversity of the core set was further validated using simple sequence repeat marker data (116 polymorphic fragments), which confirmed that the selected core set retained high levels of molecular genetic diversity.