Genetic variation in polyploid forage grass: Assessing the molecular genetic variability in the Paspalum genus

Author(s)

Cidade, Fernanda W. ^[1] ; Vigna, Bianca B. Z. ^[2] ; de Souza, Francisco H. D. ^[2] ; Valls, Jose Francisco M. ^[3] ; Dall'Agnol, Miguel ^[4] ; Zucchi, Maria I. ^[5] ; de Souza-Chies, Tatiana T. ^[6] ; Souza, Anete P. ^{[1, 7]}

Affiliation

^[1] Univ Campinas UNICAMP, Ctr Mol Biol & Genet Engn CBMEG, BR-13083875 Campinas, SP - Brazil

^[2] Brazilian Agr Res Corp Embrapa Southeast Livestoc, BR-13560970 Sao Carlos, SP - Brazil

^[3] Embrapa Genet Resources & Biotechnol, BR-70770917 Brasilia, DF - Brazil

^[4] Univ Fed Rio Grande do Sul, Fac Agron, BR-91501970 Porto Alegre, RS - Brazil

^[5] Agencia Paulista Tecnol Agronegocios APTA, BR-13400970 Piracicaba, SP - Brazil

^[6] Univ Fed Rio Grande do Sul, Dept Bot, BR-91501970 Porto Alegre, RS - Brazil

^[7] Univ Campinas UNICAMP, Inst Biol, Dept Plant Biol, BR-13083875 Campinas, SP - Brazil

• Document type: Journal article
• Source: BMC GENETICS; v. 14, JUN 8 2013.
• Web of Science Citations: 21

Abstract

Background: 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. Results: Seventeen new polymorphic microsatellites were developed for Paspalum atratum Swallen and Paspalum notatum Flugge, 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). Conclusions: 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. (AU)