Synthesis of new plant material and development of molecular tools for improving species of the Plicatula group of Paspalum

NOVO PE; AGUILERA PM; SARTOR ME; GALDEANO F; WEIHMÜLLER E; PESSINO SC; QUARIN CL; ORTIZ JPA; ESPINOZA F

Foz do Iguazu

Congreso; ? 11 th International Congress of Plant Molecular Biology; 2015

The Plicatula group of the genus Paspalum includes approximately 30 species. Most of them have foragepotential for the tropical and subtropical regions of South America. Typically, species form multiploidcomplexes with diploid (2n=2x=20) sexual cytotypes and tetraploid (2n=4x=40) apomictic counterparts.The objective of this work was to develop novel sexual genotypes and molecular tools for breeding andfundamental analysis of apomixis in the group. After chromosome doubling of a diploid plant of P.plicatulum a 100 % sexual autotetraploid individual (4PT) was obtained. Clones of 4PT were crossed withdifferent tetraploid apomictic genotypes to generate segregating populations. Among the F1 progenies,sexual hybrids were selected using the flow cytometric seed screen method. Then, phenotypic andgenotypic characterization was used for developing a completely sexual synthetic population with a widegenetic base. On the other hand, one interspecific hybrid F1 progeny of 211 plants segregating forreproductive mode was generated by crossing P. plicatulum (4PT) x P. guenoarum (4xA). Markersegregation analysis of F1 showed that both species displayed tetrasomic inheritance. This populationwas used for the construction a core genetic linkage map of the apomictic parent base on AFLP markers.The genetic map contained 127 markers distributed on 23 linkage groups, which spanned on 1,393 cM.Two markers linked in coupling at both sides of apomixis locus (at 4 and 7 cM) were detected. Ourresults provided novel genotypes and molecular markers for breeding species of the group and taggingthe apomixis determinants.