Submitted to: HortScience
Publication Type: Abstract Only
Publication Acceptance Date: 5/20/2002
Publication Date: N/A
Citation: N/A Interpretive Summary:
Technical Abstract: An intra-accession marker analysis of 15 Spanish melon landraces group Inodorus (C. melo L.) of diverse geographic origin and fruit morphology was carried out as an appraisal of population structure for structuring future bulk analyses. Sixteen individuals of each accession were assessed using 100 RAPD bands produced by 36 primers, and 12 SSR loci (23 alleles). A relatively high level of polymorphism (25.5%) was detected using RAPD markers and eight SSR loci were informative for discrimination of the accessions. Cluster analysis using RAPD- and SSR- based genetic distance estimates resulted in similar grouping of most of the accessions, generally according to their geographic origin. The mean genetic distance (GD) among accessions estimated by RAPD variation was 0.42 +/-.09, and the SSR-based GD estimates were 0.29 +/-0.15. Deviation from test ratio (64.6% of segregating RAPD markers) and from Hardy-Weinberg expectations for many putative loci per accession (91.7% of SSR loci) suggests some populations were in genotypic disequilibrium. Although allelic fixation was detected in these populations the relatively high level of heterogeneity indicates that these accesssions possess a relatively broad genetic background. Results indicate that bulk sampling techniques coupled with molecular analysis employing discriminating markers can be effective for large collection diversity analyses.