Genetic diversity and structure of natural Dactylis glomerata L. populations revealed by morphological and microsatellite-based (SSR/ISSR) markers.

Dactylis glomerata L. is an important forage species in the Mediterranean region, and in other regions with a similar climate. Genetic material from 3 locations in north, central, and south Greece was studied, using morphological traits, SSR, and ISSR molecular markers. Morphological analysis revealed differences among the geographic locations studied for all morphological traits, except the number of reproductive tillers. Moreover, the highest phenotypic variation was observed on the accessions from south, while the lowest was observed on the accessions from the north. Although the results of the molecular marker analysis are indicative, a high level of genetic diversity at the species level was revealed by ISSRs (GST=0.291) and SSRs (FST=0.186). Analysis of molecular variance showed that a high level of genetic diversity existed for ISSRs and SSRs within populations (62 and 83%, respectively), rather than among populations (38 and 17%, respectively). Cluster analysis divided the 3 populations in 2 groups, with the population originating from the island of Crete forming 1 group, while the populations from north Greece (Taxiarchis) and central Greece (Pertouli) were clustered in a 2nd group. In general, the results indicate that SSRs are more informative compared to ISSRs about the genetic variation within a population, whereas the ISSRs were more informative about the genetic diversity among populations However, a similar trend in diversity (genotypic and phenotypic) was observed in the morphological traits and microsatellite-based (SSR/ISSR) markers at the locations studied.

A multi-farm assessment of Greek black pig genetic diversity using microsatellite molecular markers.

Local breeds are important for the maintenance of genetic diversity and future food security. Nowadays, the worldwide distribution of pigs is dominated by a few breeds, tending towards a severe loss of pig biodiversity. Thus, it is critical to maintain distinct populations of pig breeds. The Greek black pig, a breed raised locally and known for the high quality of its meat for cured products, is the only traditional indigenous pig breed reared in Greece. We investigated the genetic diversity, based on microsatellite analysis, of the Greek black pig and evaluated its genetic uniqueness. One hundred and three pigs from 12 Greek farms were analyzed using 11 microsatellites. The total number of alleles amounted to 135, with a mean number of alleles per locus of 12.27, ranging between 10 and 16 alleles. The observed heterozygosity ranged from 0.363 to 0.825 per locus. The expected heterozygosity ranged from 0.471 to 0.707. The inbreeding coefficient ranged from -0.329 to 0.229. We conclude that the Greek black pig, despite its low population size, has a high degree of genetic variability, which will be useful for breeding programs aimed at maintaining long-term survival of this ancient breed.

Agronomic characterization, genetic diversity and association analysis of cotton cultivars using simple sequence repeat molecular markers.

Cotton is the most important textile plant in the world and is one of the most important crops for the production of oilseed. Because of its worldwide economic importance, new cultivars are constantly being released in the world and consequently in the Greek market, as Greece is the largest producer in Europe. We used simple sequence repeat (SSR) markers for the identification and the phylogenetic analysis of the most widely cultivated cotton cultivars in Greece. Initially, we used 12 pairs of SSR molecular markers for the analysis of 29 cultivars of Gossypium hirsutum and an interspecific hybrid (G. hirsutum x G. barbadense). Of the 12 pairs of SSR primers, 11 amplified polymorphic products, while one pair did not amplify any product. Globally, 17 polymorphic marker loci were identified. Two to four different alleles were amplified at each genomic locus, with a mean of 2.53 alleles per locus. Among the 30 genotypes that we analyzed, the polymorphism information content ranged from 0 to 0.548, with a mean of 0.293. Three main groups were formed among the 30 genotypes when a phylogenetic analysis was performed using UPGMA. Computational analysis of each molecular marker separately showed an association of SSR markers with agronomic traits such as fiber quality. To our knowledge, this is the first in-depth molecular analysis of cotton cultivars grown in Greece using SSR markers. An analysis of association of SSR markers with fiber quality traits of 29 cotton cultivars is reported for the first time.