No abstract

Fruit physical and chemical characters of 29 apricot cultivars of Greek and American origin and their hybrids were evaluated using correlation and principal component analysis. A remarkable variation was observed in the total phenol content (0.3-7.4 mg gallic acid equivalent g(-1) FW) and total antioxidant capacity (0.026-1.858 mg ascorbic acid equivalent g(-1) FW), with the American origin cultivars Robada and NJA(2) and the new cultivar Nike exhibiting the greatest values. The cultivar Tomcot and hybrid 467/99 had the highest content of total carotene (37.8 microg beta-carotene equivalent g(-1) FW), which was up to four times greater as compared with the rest of studied genotypes. The dominant sugar in fruit tissue was sucrose, followed second by glucose and third by sorbitol and fructose-inositol. The new cultivars Nike, Niobe, and Neraida contained relatively higher contents of sucrose and total sugars, while Ninfa and P. Tirynthos contained relatively higher contents of K, Ca, and Mg. Correlation analysis suggested that late-harvesting cultivars/hybrids had greater fruit developmental times (r = 0.817) and contained higher sugar (r = 0.704) and less Mg contents (r= -0.742) in fruit tissue. The total antioxidant capacity was better correlated with the total phenol content (r = 0.954) as compared with the total carotenoid content (r = 0.482). Weak correlations were found between the fruit skin color and the antioxidant contents in flesh tissue. Multivariate analysis allowed the grouping of variables, with more important variables being the harvest date, fruit developmental time, skin Chroma, sorbitol, and total sugar, K and Mg contents. Plotting the genotypes in a dendrogram revealed cases of homonymy between parents and hybrids, although independent segregation of the measured traits after hybridization was also found.

Hazelnut (Corylus avellana L.) is a traditional nut crop in southern Europe. Germplasm exploration conducted on-farm in five countries (Portugal, Spain, Italy, Slovenia, and Greece) identified 77 landraces. The present work describes phenotypic variation in nut and husk traits and investigates genetic relationships using ten simple sequence repeat (SSR) markers among these landraces, 57 well-known references cultivars, and 19 wild accessions. Among the 77 landraces, 42 had unique fingerprints while 35 showed a SSR profile identical to a known cultivar. Among the 42 unique landraces, morphological observations revealed high phenotypic diversity, and some had characteristics appreciated by\ud the market such as nut round and caliber. Analysis of genetic relationships and population structure allowed investigation of the origin and spread of the cultivated germplasm in southern Europe. Our results indicate the existence of three primary centers of diversity in the Mediterranean basin: northwestern Spain (Tarragona) and southern Italy (Campania) in the West and Black Sea (Turkey) in the East. Moreover, the data suggest the existence of secondary gene pools in the Iberian (Asturias) and Italian (Liguria and Latium) Peninsulas, where\ud local varieties were recently domesticated from wild forms and/or from introduced ancient domesticated varieties

In the frame of SAFENUT AGRI GEN RES Action, which was a European strategy for the recovery, characterization and conservation of genetic resources, the fatty acids and the tocopherol profiles of a set of 75 hazelnut accessions were analyzed. The aim of this study was to assess the genetic differences among the European germplasm, contributing to the definition of nut quality in traditional European areas of cultivation. Significant differences were found between accessions for oil amount and contents of most fatty acids. As expected, monounsaturated fatty acids made up the largest portion (mean 80.85 %) followed by polyunsaturated fatty acids (10.70 %). The saturated ones were the minor components and accounted for only 8.43 % of the total fatty acids. On the basis of Student's test, significant differences between the 2 years of harvest were found for fatty acid content, except for linoleic acid, the ratio of polyunsaturated, a-tocopherol and the stability index. When the oil content was studied in cultivars from the same site of cultivation, the mean values of the genetic pools from central Italy (60.8 %), Slovenia (59.3 %) and Portugal (58.2 %) showed highest values than those of cultivars grown in Greece (56.8 %), Spain (55.9 %) and France (51.5 %). A chemometric approach based on principal component and clustering analyses was developed to identify the most interesting cultivars for breeding programs.