Genetic variation in polyploid forage grass: Assessing the molecular genetic variability in the Paspalum genus
1 Center for Molecular Biology and Genetic Engineering (CBMEG), University of Campinas (UNICAMP), CP 6010, Campinas, SP CEP 13083-875, Brazil
2 Brazilian Agricultural Research Corporation (Embrapa) Southeast Livestock, CP 339, São Carlos, SP CEP 13560-970, Brazil
3 Embrapa Genetic Resources and Biotechnology, Parque Estação Biológica - PqEB, CP 02372, Brasília, DF CEP 70770-917, Brasil
4 Faculty of Agronomy, Federal University of Rio Grande do Sul, Av. Bento Gonçalves, 7712 Agronomia, Porto Alegre, Rio Grande do Sul CEP 91501-970, Brazil
5 Agência Paulista de Tecnologia dos Agronegócios/APTA, Km 30, CP 28, Pólo Regional Centro Sul, Rodovia SP127, Piracicaba, SP CEP13400-970, Brazil
6 Department of Botany, Prédio 43433, Federal University of Rio Grande do Sul, Av. Bento Gonçalves, 9500 Agronomia, Porto Alegre, Rio Grande do Sul, CEP 91501-970, Brazil
7 Department of Plant Biology, Biology Institute, University of Campinas (UNICAMP), CP 6109 Campinas, SP, CEP 13083-875, Brazil
BMC Genetics 2013, 14:50 doi:10.1186/1471-2156-14-50Published: 8 June 2013
Paspalum (Poaceae) is an important genus of the tribe Paniceae, which includes several species of economic importance for foraging, turf and ornamental purposes, and has a complex taxonomical classification. Because of the widespread interest in several species of this genus, many accessions have been conserved in germplasm banks and distributed throughout various countries around the world, mainly for the purposes of cultivar development and cytogenetic studies. Correct identification of germplasms and quantification of their variability are necessary for the proper development of conservation and breeding programs. Evaluation of microsatellite markers in different species of Paspalum conserved in a germplasm bank allowed assessment of the genetic differences among them and assisted in their proper botanical classification.
Seventeen new polymorphic microsatellites were developed for Paspalum atratum Swallen and Paspalum notatum Flüggé, twelve of which were transferred to 35 Paspalum species and used to evaluate their variability. Variable degrees of polymorphism were observed within the species. Based on distance-based methods and a Bayesian clustering approach, the accessions were divided into three main species groups, two of which corresponded to the previously described Plicatula and Notata Paspalum groups. In more accurate analyses of P. notatum accessions, the genetic variation that was evaluated used thirty simple sequence repeat (SSR) loci and revealed seven distinct genetic groups and a correspondence of these groups to the three botanical varieties of the species (P. notatum var. notatum, P. notatum var. saurae and P. notatum var. latiflorum).
The molecular genetic approach employed in this study was able to distinguish many of the different taxa examined, except for species that belong to the Plicatula group, which has historically been recognized as a highly complex group. Our molecular genetic approach represents a valuable tool for species identification in the initial assessment of germplasm as well as for characterization, conservation and successful species hybridization.