Anchored inter-simple sequence repeats (ISSR) were used to identify 21 accessions of Jacaranda mimosifolia, collected mainly in Buenos Aires City, and the others in Mendoza, Salta and Jujuy Province and La Plata City, as part of an ornamental breeding program. DNA was extracted and purified from young leaves and amplified by four anchored primers based on dinucleotide repeats with 5' or 3´extension. A total of 42 polymorphic bands, obtained after electrophoresis in agarose gels stained with ethidium bromide, were used to construct a molecular identification matrix. A mean of 12.75 bands per primer were generated, ranging from 140 to 1,400 bp. The genomic relationship of the genotypes was evaluated using Jaccard coefficient, and the dendrogram was constructed using UPGMA linkage method. All the accessions were differentiated by this technique, which showed a range of Resolving Power from 1.2 to 5.721. The anchored microsatellite analysis was shown to be a promising method to identify selected material in a breeding program of J. mimosifolia and with high potential to be applied to other ornamental crops.

Six Nierembergia linariaefolia clones were selected for ornamental traits during a native germplasm development program. For fingerprinting diagnosis, 13 anchored inter-simple sequence repeat (ISSR) primers and 6 amplified fragment length polymorphism (AFLP) primer-enzyme combinations were used. Both markers revealed high levels of polymorphism, enabling genetic discrimination of the accessions analyzed by using 443 informative ISSRs and 541 AFLP markers. Both molecular techniques are suitable for monitoring genetic diversity in Nierembergia linariaefolia and, under our experimental conditions, they showed correlation coefficients of 0.629 for similarity matrices and of 0.649 in the cophenetic matrices. These results suggest that ISSRs are a good choice for DNA analysis in N. linariaefolia when simple manipulation and a low budget are required.

Background: Calibrachoa Cerv. (ex La Llave & Lexarza) is a genus of the Solanaceae family (La Llave and Lexarza, 1825). This genus has a high ornamental and economic value due to its intrinsic variability and multiplicity of flower colours. In Argentina there are eight native species, and one of them is Calibrachoa caesia. The genetic diversity among 35 accessions of C. caesia, from five departments in the province of Misiones, was analyzed using ISSR markers. Results: Thirteen ISSR primers yielded a reproducible banding pattern, with 701 amplified loci and 98% of polymorphism. The ISSR primers 5'CT, 5'CA, 5'GA, 5'GACA, 3'CAC, 3'TG and 3'TC generated 100% polymorphic patterns. The Rp values ranged from 23.20 to 10.29 for 5'GACA and 3'AG primers, respectively, while the average values for MI and PIC were 0.367 and 0.231, respectively. The more informative primers were 5'GACA and 5'GA, and the less informative was 3'AC. Simple matching coefficient of similarity varied from 0.8875 to 0.6659, indicating high levels of genetic similarity among the genotypes studied. The UPGMA cluster analysis indicated three distinct clusters; one comprised genotypes of the five departments, while the second included individuals from Guaraní and Oberá regions and the third cluster included the San Pedro individuals. The overall grouping pattern is in agreement with principal coordinate analysis (PCoA). Conclusions: The Bayesian cluster analysis revealed structuring of the C. caesia population and two clusters were identified, which correspond to UPGMA major clades. The AMOVA test for all populations showed highest genetic variation within populations (90%), meanwhile the F st coefficient was 0.098, indicating a medium differentiation between populations. These results showed a great intrapopulation genetic diversity but no significant difference was detected among populations. In this work the use of thirteen ISSR markers, allowed the characterization of every individual examined. Therefore, the possibility of using molecular data for varietal identification is a promising tool for application in future breeding programs in the genus Calibrachoa.Note: Electronic Journal of Biotechnology is not responsible if on-line references cited on manuscripts are not available any more after the date of publication. Supported by UNESCO / MIRCEN network.

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