Search results for "UPGMA"
showing 10 items of 16 documents
Preserving Biodiversity in Marginal Rural Areas:Assessment of Morphological and Genetic Variabilityof a Sicilian Common Bean Germplasm Collection
2020
The historical cultivation of common bean (Phaseolus vulgaris L.) has resulted in the development of local populations/cultivars in restricted Italian rural areas. Many common bean landraces, still cultivated in small mountain areas from Sicily, have become outdated and endangered due to the commercial varieties spreading. These accessions are poorly known but often represent a genetic heritage to be preserved and enhanced. The ex situ conservation of fifty-seven Sicilian common bean landraces was carried out at the &ldquo
Genetic relationships between Sicilian wild populations of Brassica analysed with RAPD markers
2001
Brassica comprises very variable species, both morphologically and genetically. Among these species, the Sicilian populations of Brassica sect. Brassica, species related to kale crops form a complex group. The genetic relationships among 15 populations occurring in Sicily and one from Calabria, representing the existing diversity, have been investigated using random amplified polymorphic DNA (RAPD) markers. This assay, carried out with 22 arbitrary primers, generated 236 polymorphic fragments, 21 of which were specific for single populations (mainly Brassica insularis, Brassica incana and Brassica macro-carpa). Jaccard's genetic distances were computed and the phylogenic tree was establishe…
Taxonomic Study of Linaria depauperata and L. supina Complexes in Eastern Spain
2001
Abstract Morphological characteristics were studied in two groups of closely related taxa of section Supinae , Linaria depauperata and L. supina , from eastern Spain. Vegetative, floral and seed characteristics were of little use in distinguishing between these taxa as the ranges for all the taxa studied overlapped. Flower colour could be used as a diagnostic character for some but not all of these taxa. Seed coat characters were of high taxonomic value, both when trying to distinguish among these two groups, and the taxa included within them, and also when establishing relationships among the taxa studied. Some differences were found in the indumentum distribution and density. Three types …
TESTING SIMILARITY COEFFICIENTS FOR ANALYSIS OF THE FOSSIL RECORD USING CLUSTERING METHODS: THE PALAEOZOIC FLORA AS A STUDY CASE
2020
This paper reports a global methodological approach based on the similarity and clustering methods of the Palaeozoic plant fossil record using a comparative approach between two similarity measures: the Jacard and Raup-Crick Coefficients. The results show that although the Raup-Crick Coefficients clearly have the potential for providing more robust results, the consequences of the extinction processes are better reflected in the similarity analysis based on the Jaccard Coefficients. On the other hand, the cluster analysis based on UPGMA algorithm shows four robust clusters and reveals new evidence for the singularity of Mississippian flora. Finally, the results obtained reveal that similari…
Amplified fragment length polymorphism (AFLP) and biochemical typing of Photobacterium damselae subsp. damselae.
2002
Aims: The aim of the present study was to characterize subspecifically Photobacterium damselae subsp. damselae strains isolated from cultured Sparus aurata and Dicentrarchus labrax by means of phenotypic and molecular typing techniques (amplified fragment length polymorphism, AFLP). Methods and Results: Seventy-one strains of P. damselae subsp. damselae were isolated from 38 cultured fishes at different fish farms located on the Mediterranean coast near Valencia, Spain. Most fish studied were asymptomatic and some were recovered during infectious outbreaks. Phenotypic characterization revealed a considerable degree of variability within the subspecies, including some characters, such as pro…
Genetic diversity and clonal variation within the main Sicilian olive cultivars based on morphological traits and microsatellite markers
2014
The richness of Olea europaea (L.) genetic resources in Sicily is well documented. In the last 30 years, mostof the local cultivars, landraces and ecotypes have been gathered together in a large ex-situ collection,containing more than 300 genotypes. In this study, 45 putative clones of the main Sicilian olive cultivarswere characterized morphologically using microsatellite markers to unambiguously identify possiblesuperior genotypes. The microsatellites employed were polymorphic (observed heterozygosity = 0.71;polymorphic information content = 0.59), discriminated 52% of the genotypes and enabled the detectionof intra-cultivar polymorphism, derived from both somatic mutations, indicating th…
On the Specificity of PCR Detection of Listeria monocytogenes in Food: a Comparison of Published Primers
2002
A total of nine pairs of primers, seven previously published and two newly developed, have been assayed for PCR detection of Listeria monocytogenes in food. They have been tested for specificity on a total of 72 strains including reference and food isolates belonging to L. monocytogenes and other species in the genus. First of all, a polyphasic approach has been carried out in order to establish a reference strain collection. They were biochemically and genetically characterized by API-Lis and randomly amplified polymorphic DNA PCR (RAPD-PCR), respectively. Random amplification of DNA was performed with M13, T7 and T3 universal primers and a data bank was created to compile the RAPD pattern…
Genetic analysis of Citrus aurantium L. (Rutaceae) cultivars by ISSR molecular markers
2011
Eight cultivars of Citrus aurantium L., showing peculiar morphological traits of the fruits and leaves, were analyzed genetically. Inter simple sequence repeat (ISSR) was chosen as molecular markers because they represent a highly efficient system for investigating variability at intraspecific level. The particular morphological traits were discussed, the genetic identity and distance matrix based on Nei index was calculated, and the unweighted pair group method with arithmetic mean (UPGMA) dendrogram was generated. A total of 53 clearly distinguished DNA bands were considered for the ISSR analysis of which 24 were polymorphic. A basic C. aurantium fingerprinting pattern was obtained. The I…
Reticulation or divergence: the origin of a rare serpentine endemic assessed with chloroplast, nuclear and RAPD markers
2002
Species of Armeria from the southern part of the Iberian Peninsula have been postulated to undergo extensive reticulate evolution based on ITS sequences as well as morphometric, eco-geographical evidence and crossing experiments. The hypothesis that a rare serpentine endemic (A. villosa subsp. carratracensis) originated from a cross between another serpentine tolerant endemic (A. colorata) and a widespread limestone species (A. villosa subsp. longiaristata) is tested with molecular markers. Sequences from two chloroplast regions [trnL (UAA)-trnF (GAA) and trnD (GUC)-trnT (GGU)], from nuclear ribosomal DNA (ITS-1 + 5.8S + ITS-2) as well as RAPD data are used. Variation in chloroplast and nuc…
Genetic relationships, structure and parentage simulation among the olive tree (Olea europaea L. subsp. europaea) cultivated in Southern Italy reveal…
2013
In this work, we assess both the morphological and genetic diversity of 68 important olive cultivars from three Southern Italian regions: Calabria, Campania and Sicily. Twenty-five phenotypic traits were evaluated and 12 simple sequence repeat (SSR) markers were analysed. All SSR primers were polymorphic and reliable. The total number of alleles per locus varied from 5 to 19 with an average number of 13.1 and a mean polymorphic information content (PIC) of 0.81. These results suggested high genetic diversity within these three olive germplasm collections. Morphological traits also showed significant variability amongst cultivars. Two cases of identity were found and ten statistically signif…