Characterization of Opuntia spp. by Means of Seed with RAPD and ISSR Markers and Its Possible Use for Differentiation
Keywords:cactus pear, genetic variability, interspecific distinction, PCR, DNA fingerprinting, multivariate analysis.
To use precise methods for characterization and to differentiate plants in the germplasm banks saves time in the selection of elite genotypes. In occasions this work is not easy, because depending on the species, the morphological descriptors can be insufficient to separate related accessions or species, like in the case of some commercial varieties and local accessions of cactus pear (Opuntia spp.) native of Mexico. The use of markers of DNA has also been limited by the excess of polysaccharides that are obtained simultaneously with this molecule that makes difficult the analyses with PCR. The obtained DNA of seed lacks of these compounds and besides the characterization of seeds can contribute with information related to the genetic variability. In this study 22 cactus pear varieties were characterized with markers RAPD and ISSR using DNA from seeds and were separated in polyacrylamide gels. The RAPD as ISSR profiles revealed differences between the considered varieties and species. The different clusters showed agreement to each other, and in their majority they were related with the current taxonomic groups described except for ‘Burrona’ and ‘Camuezo’ that were located in an unrelated genomic group. Particularly in ‘Burrona’ polymorphism was detected among the replications, contrary to the rest of the varieties that didn’t show it.