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Grattapaglia D.,Laboratorio Of Genetica Vegetal | Grattapaglia D.,Catholic University of Brasilia | do Amaral Diener P.S.,Catholic University of Brasilia | do Amaral Diener P.S.,HEREDITAS Tecnologia em analise de DNA Ltda. | dos Santos G.A.,Klabin S.A.
Tree Genetics and Genomes | Year: 2014

Mass controlled pollination (MCP), involving large-scale application of pollen on physically isolated female reproductive organs, has been a lower cost alternative to controlled pollination for the commercial production of genetically improved seeds. Nevertheless, rare are the studies that examined the efficacy of operational MCP and no such assessment has been done in loblolly pine to date. The success of MCP was assessed by a microsatellite-based investigation of the realized versus expected parentage of a set of 300 Pinus taeda offspring in 19 families generated in two subsequent rounds of MCP in 2005 and 2006 in a clonal seed orchard in Brazil. Multi-locus combined probability of parentage exclusion both theoretical and realized from actual testing was >99 % for single parent and parent pair testing when using nine or ten markers. Parentage assignments carried out under a maximum likelihood framework revealed a significantly higher success rate of MCP in 2006 (84 %) following technical improvements adopted to minimize pollen contamination and maximize male reproductive success, although significant variability in the correct maternity and full parentage was seen among individual families. The observed patterns of unexpected parentage indicated that this variability likely resulted from mislabeling of clonal ramets of the parents used in the crosses which impacted both maternity and paternity. Preventing pollen contamination will not be sufficient for successful MCP if inaccuracies exist in the identity of the clonal plants that ultimately provide pollen and female strobili, showing that DNA marker auditing and correction of identity of all ramets in a clonal seed orchard should be a standard practice in the operational implementation of MCP. © 2014, Springer-Verlag Berlin Heidelberg.

Correa L.C.,Sao Paulo State University | Santos C.A.F.,Laboratorio Of Genetica Vegetal | Vianello F.,University of Padua | Lima G.P.P.,Sao Paulo State University
Plant Genetic Resources: Characterisation and Utilisation | Year: 2011

Guava (Psidium guajava) and araçá (Psidium spp.) plants are important for the Brazilian economy, as their fruit is both accepted by the consumers, and makes a beneficial contribution to the human diet thanks to their content in vitamin C, carotenoids and phenolic compounds. Here, we report the content in the fruit of free ascorbic acid, lycopene, Î-carotene, flavonoids and phenolic compounds, and the total antioxidant activity present in a collection of guava and araçá accessions curated at the Embrapa Semiarido germplasm bank. Guava fruits with a red-coloured pulp flesh contained a significant amount of carotenoids, especially lycopene, and a high concentration of phenolic compounds. These compounds were largely responsible for the antioxidant activity of the araçá accessions. Among the guava accessions, phenolic compounds were also responsible for the antioxidant activity. High levels of free ascorbic acid were present in most accessions. In both guava and araçá, there is substantial potential to develop cultivars with a good level of consumer acceptability. © 2011 NIAB.

Sujii P.S.,University of Campinas | Martins K.,Federal University of Sao Carlos | Wadt L.H.O.,Embrapa Acre | Azevedo V.C.R.,Laboratorio Of Genetica Vegetal | Solferini V.N.,University of Campinas
Conservation Genetics | Year: 2015

Population genetic structure and genetic diversity levels are important issues to understand population dynamics and to guide forest management plans. The Brazil nut tree (Bertholletia excelsa Bonpl.) is an endemic species, widely distributed through Amazonian upland forests and also an important species for the local extractive economy. Our aim was to analyze the genetic structure of Brazil nut trees at both fine and large scales throughout the Amazon Basin, contributing to the knowledge base on this species and to generate information to support plans for its conservation. We genotyped individuals from nine sites distributed in five regions of the Brazilian Amazon using 11 microsatellite loci. We found an excess of heterozygotes in most populations, with significant negative inbreeding coefficients (f) for five of them and the fine-scale structure, when present, was very small. These results, as a consequence of self-incompatibility, indicate that conservation plans for B. excelsa must include the maintenance of genetic diversity within populations to ensure viable amounts of seeds for both economic purposes and for the local persistence of the species. © 2015, Springer Science+Business Media Dordrecht.

Gama R.N.C.S.,State University of Feira de Santana | Santos C.A.F.,Laboratorio Of Genetica Vegetal | Dias R.C.S.,Laboratorio Of Genetica Vegetal
Genetics and Molecular Research | Year: 2013

We analyzed the genetic variability of 40 watermelon accessions collected from 8 regions of Northeastern Brazil using microsatellite markers, in order to suggest strategies of conservation and utilization of genetic variability in this species. These accessions are not commercial cultivars. They were sampled in areas of traditional farmers that usually keep their own seeds for future plantings year after year. An UPGMA dendrogram was generated from a distance matrix of the Jaccard coefficient, based on 41 alleles of 13 microsatellite loci. Analysis of molecular variance was made by partitioning between and within geographical regions. The similarity coefficient between accessions ranged from 37 to 96%; the dendrogram gave a co-phenetic value of 0.80. The among population genetic variability was high (φST = 0.319). Specific clusters of accessions sampled in 3 regions of Maranhão were observed while the other 5 regions did not presented specific clusters by regions. We conclude that watermelon genetic variability is not uniformly dispersed in the regions analyzed, indicating that geographical barriers or edaphoclimatic conditions have limited open mating. We suggest sampling a greater number of populations, so regional species diversity will be better represented and preserved in the germplasm bank. © FUNPEC-RP.

Aksoy S.,Yale University | Almeida-Val V.M.F.,National Institute of Amazonian Research | Azevedo V.C.R.,Laboratorio Of Genetica Vegetal | Baucom R.,University of Cincinnati | And 62 more authors.
Molecular Ecology Resources | Year: 2013

This article documents the addition of 153 microsatellite marker loci to the Molecular Ecology Resources Database. Loci were developed for the following species: Brassica oleracea, Brycon amazonicus, Dimorphandra wilsonii, Eupallasella percnurus, Helleborus foetidus, Ipomoea purpurea, Phrynops geoffroanus, Prochilodus argenteus, Pyura sp., Sylvia atricapilla, Teratosphaeria suttonii, Trialeurodes vaporariorum and Trypanosoma brucei. These loci were cross-tested on the following species: Dimorphandra coccicinea, Dimorphandra cuprea, Dimorphandra gardneriana, Dimorphandra jorgei, Dimorphandra macrostachya, Dimorphandra mollis, Dimorphandra parviflora and Dimorphandra pennigera. © 2013 Blackwell Publishing Ltd.

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