Molecular Genetic Variability, Population Structure and Mating System in Tropical Forages

Microsatellite (SSR) markers were developed for the following tropical forage species, using accessions available from the plant genetic resources (PGR) collections held by EMBRAPA (Brazilian Agricultural Research Corporation): Brachiaria brizantha, B. humidicola, Panicum maximum, Paspalum spp., Stylosanthes capitata, S. guianensis, S. macrocephala, Calopogonium mucunoides and Centrosema spp. The markers were used to analyse population structure and genetic diversity, evolution and origin of the genetic variability in the centre of origin, mating systems and genetic resources in EMBRAPA’s germplasm bank. The results shed light on the amount of genetic variation within and between populations, revealed the need in some cases for further plant collection to adequately represent the species in PGR collections, allowed us to assemble core collections (subsets of the total collections) that should contain most of the available diversity and (in the case of the legumes) showed the need to avoid unwanted outcrossing when regenerating conserved material. The data will allow plant breeders to better select accessions for hybrid production, discriminate between genotypes and use marker-assisted selection in breeding programs. Our results will also underpin the construction of genetic maps, mapping of genes of agronomic interest and numerous other studies on genetic variability, population structure, gene flow and reproductive systems for the tropical forage species studied in this work

Isolation and characterization of microsatellite markers from the stingless bee Nannotrigona testaceicornis

Conservation of natural populations and handling of breeding programs would benefit from the availability of molecular markers. Stingless bees are one of the most important pollinators in several ecosystems. Thus, seventeen microsatellite markers were developed from an enriched genomic library of Nannotrigona testaceicornis. They were characterized using 50 samples. The expected and observed heterozygosities ranged from 0.59 to 0.89 and from 0.39 to 0.79, respectively. These markers will contribute to advance researches on the genetic conservation, characterization and preservation of the Brazilian native bees119799CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQCOORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPESFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESPsem informaçãosem informação2004/15801-

Isolation and characterization of microsatellite markers from the stingless bee Nannotrigona testaceicornis

Conservation of natural populations and handling of breeding programs would benefit from the availability of molecular markers. Stingless bees are one of the most important pollinators in several ecosystems. Thus, seventeen microsatellite markers were developed from an enriched genomic library of Nannotrigona testaceicornis. They were characterized using 50 samples. The expected and observed heterozygosities ranged from 0.59 to 0.89 and from 0.39 to 0.79, respectively. These markers will contribute to advance researches on the genetic conservation, characterization and preservation of the Brazilian native bees.BIOTA-FAPESP[2004/15801-0]FAEPACNPqCAPE

Isolation of microsatellite loci in the Amazon sailfin catfish Pterygoplichlhys pardalis (Castelneau, 1855) (Teleostei: Loricariidae)

Pterygoplichlhys pardalis is an important freshwater ornamental fish in the Amazon Basin. Studies involving populations of P. pardalis are of great importance for the conservation and management of this species. We developed nine microsatellite loci and applied them to investigate the genetic variation of 20 wild individuals from floodplain lakes of the Solimões river. The number of alleles per locus ranged from 2 to 12, with an average of 6. 6. The observed and expected heterozygosity values ranged from 0. 400 to 0. 923 (average 0. 706) and from 0. 358 to 0. 895 (average 0. 692), respectively. The value of f ranged from -0. 532 to 0. 467 (average 0. 032). One locus (Pp07) significantly deviated from Hardy-Weinberg equilibrium after Bonferroni correction (P: (5 %) < 0. 006). No significant linkage disequilibrium was detected. These microsatellite loci will contribute towards studies of genetic diversity and conservation of P. pardalis. © 2012 Springer Science+Business Media B.V