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AFLP Primer Combinations (aflp + primer_combination)
Selected AbstractsUtility of AFLP markers for the assessment of genetic diversity within Brassica nigra germplasmPLANT BREEDING, Issue 1 2004M. S. Negi Abstract Genetic diversity of 18 Brassica nigra accessions was estimated using amplified fragment length polymorphism (AFLP) marker technology. Two B. rapa and two B. juncea accessions were selected as outliers in the study. Eight AFLP primer combinations generated a total of 426 bands, of which 79% were polymorphic. The UPGMA method was employed to construct a dendrogram based on the Jaccard's similarity coefficient. The accessions of B. rapa separated from those of B. nigra at a genetic similarity coefficient of 0.27 while those of B. juncea did so at 0.5. The genetic similarity coefficients within the B. nigra accessions ranged from 0.58 to 0.86. Based on these coefficients it was concluded that the B. nigra accessions show high levels of genetic variation. These results have significant implications in the crop improvement programmes for the agronomically important crop B. juncea, an amphidiploid of B. nigra and B. rapa. Two incorrectly labelled B. nigra accessions were also identified. These accessions were found to cluster with those of B. juncea accessions. This result demonstrates the great value of AFLP markers in the management of genebanks. [source] Molecular characterization of novel resynthesized rapeseed (Brassica napus) lines and analysis of their genetic diversity in comparison with spring rapeseed cultivars,PLANT BREEDING, Issue 6 2003F. Seyis Abstract Resynthesized (RS) rapeseed generated from interspecific hybridization between suitable forms of Brassica rapa L. (syn. campestris; genome AA, 2n = 20) and B. oleracea L. (CC, 2n = 18) represents a potentially important resource to expand genetic diversity in the narrow gene pool of oilseed rape (B. napus L., AACC, 2n = 38). In this study 165 RS rapeseed lines originating from crosses between an Indian Yellow Sarson (B. rapa ssp. trilocularis) and five different cauliflower (B. oleracea convar. botrytis) cultivars were studied using amplified fragment length polymorphism (AFLP) markers and their genetic diversity was compared in relationship to an assortment of 40 diverse spring oilseed and fodder rape varieties. Using three AFLP primer combinations, a total of 467 polymorphic bands were scored. Cluster analysis allowed differentiation among the different RS lines, which, as expected, were genetically highly divergent from the cultivars. The genetic diversity of the material is discussed in relation to its morphological variability with a view to the implementation of RS lines in oilseed rape breeding. [source] Assessment of genetic diversity in clover species from Sardinia, Italy, using AFLP analysisPLANT BREEDING, Issue 4 2003S. J. Bennett Abstract Two species, Trifolium glomeratum and T. nigrescens, from Sardinia, Italy, were analysed for genetic diversity using amplified fragment length polymorphism (AFLP). Variation between and within populations was compared between the inbreeder, T. glomeratum, and the outbreeder, T. nigrescens. Four AFLP primer combinations resulted in a total of 292 loci, of which 75% were polymorphic in T. glomeratum and 85% in Trifolium nigrescens. Variation was highest between populations in both species, but the difference between populations was greater in T. glomeratum (Fst = 0.17), compared with T. nigrescens (Fst = 0.02). Cluster analysis and principal coordinates analysis were used to verify the relationships found. The high level of genetic variation within populations in both species is attributed to the movement of sheep between paddocks, the existence of both species in Sardinia for thousands of years and the persistence of a long-lived seedbank due to the production of large numbers of small seeds with high levels of hard seededness. [source] Assessing genetic diversity in indigenous Veneto chicken breeds using AFLP markersANIMAL GENETICS, Issue 2 2006M. De Marchi Summary Genetic variation in four indigenous chicken breeds from the Veneto region of Italy was assessed using amplified fragment length polymorphism (AFLP) markers. A total of 99 individuals were analysed using three AFLP primer combinations that produced 70 polymorphisms. Four indigenous Veneto chicken breeds (Ermellinata, Padovana, Pépoi and Robusta) and a reference broiler line were included in the analysis. Breed-specific markers were identified in each breed. The expected heterozygosity did not differ significantly among the indigenous Veneto chicken breeds and the broiler line. The coefficient of gene variation (Gst) value across loci indicated that almost half of the total variability was observed among breeds. Nei's standard genetic distance between pairs of breeds showed that the distance between the broiler line and the Pépoi breed was greater than the distances between the broiler line and the other three chicken breeds. Cluster analysis based on standard genetic distances between breeds indicated that the Padovana and Pépoi breeds were closely related. Factorial analysis based on a binary matrix of the AFLP data showed a clear distinction of all breeds. [source] | ||||||||||