Genetic variability assessment in the genus Passiflora by SSR marker

Molecular Genetic Variability of Commercial and Wild Accessions of Passion Fruit (Passiflora spp.) Targeting ex Situ Conservation and Breeding

“…Because assessments of microsatellite loci are based on primer pair hybridization to specific regions of the genome, different species are expected to contain some of these conserved regions, albeit in different proportions. The success rate of cross-amplification among the 14 Passiflora species evaluated (Table 1) can be considered high compared with the results presented by Paiva [51] (an average of 45%, ranging from 12.5% to 64%) and is more readily comparable to the results reported by Oliveira et al [50] (an average of 67%, ranging from 43% to 100%). The success rates for the cross-species amplification of SSR loci are highly variable among plant species; thus, it is not surprising that variation was observed among the Passiflora species evaluated herein [52].…”

“…This is the first study to investigate the molecular genetic diversity and genetic structure of a large number of commercial and wild accessions of passion fruit, including different species of the genus Passiflora . In addition, estimates of the genetic diversity of passion fruit using microsatellites have been obtained only recently and are restricted to studies that monitor diversity in full-sib progenies associated with recurrent selection programs [48,49] or studies of variability using the cross-species amplification of microsatellite loci in a few accessions of passion fruit [50,51]. …”

“…, species-specific primer pairs) are typically successfully employed to amplify microsatellite loci in closely related taxa when the DNA regions that flank the microsatellite are sufficiently conserved [41,50,51,52]. Because assessments of microsatellite loci are based on primer pair hybridization to specific regions of the genome, different species are expected to contain some of these conserved regions, albeit in different proportions.…”

“…In addition, these tests were restricted to agarose gel electrophoresis, which limits the evaluation of the amplification profiles of the loci. Recently, more robust studies of cross-amplification were conducted by Oliveira et al [50] using 11 passion fruit species and 21 SSR loci; by Paiva [51] using 10 species and 28 SSR loci; and by Cerqueira-Silva et al [41] using three species and 94 SSR loci. Together, the information provided by evaluations of cross-species amplification in the genus Passiflora attests to the effectiveness of this strategy as a means of providing genetic markers for different species of this genus at a reduced cost.…”

“…Moreover, characterizations of variability among accessions from germplasm banks using cross-amplification of SSR loci were also initiated in recent years. Interspecific diversity studies were conducted by the research group at the Universidade Estadual do Norte Fluminense, Rio de Janeiro, Brazil, where a total of 56 plants representing 10 species were evaluated using 28 SSR loci [51]. Additionally, in searches conducted as part of the Embrapa breeding program, genetic distances for a total of 61 plants representing 11 species were estimated using 21 SSR loci [50].…”