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Bressan E.A.,University of Sao Paulo | Sebbenn A.M.,Instituto Florestal Of Sao Paulo | Ferreira R.R.,University of Sao Paulo | Lee T.S.G.,Federal University of São Carlos | Figueira A.,University of Sao Paulo
Tree Genetics and Genomes | Year: 2013

The hierarchical mating system among and within fruits of Jatropha curcas was investigated in a base population using five microsatellite loci, employing mixed mating and correlated mating models. Open-pollinated fruits were collected from 15 randomly selected seed trees, sampling seven fruits per tree for a total of 21 seeds from each tree. We detected multilocus genotypes identical to the mother tree in 13 % of offspring, implying the occurrence of apomixis in J. curcas. The presumed apomictic individuals were excluded from the analysis of the remaining results. Evidence of substantial selfing was provided by the average multilocus outcrossing rate (t m = 0.683), showing that the species exhibits a mixed mating system. The outcrossing rate showed a large variation among seed trees, ranging from 0.21 to 1.0, indicating that the species is not self-incompatible. Significant differences were detected between the multilocus and the single locus outcrossing rates (t m - t s = 0.347) that suggested mating among related individuals, possibly because of the presence of individuals from the same progeny (sibs) in the base population. The multilocus paternity correlation was extremely high for the population (r p(m) = 0.999), indicating that the progenies were manly composed of full-sibs. As a consequence of selfing and a high paternity correlation, the co-ancestry coefficient within the progeny was higher (Θ = 0.369) than expected for panmictic populations. Our results indicated that J. curcas produces seeds asexually by apomixis and sexually by a mixed mating system, combining selfing and outcrossing. © 2013 Springer-Verlag Berlin Heidelberg.


de Bressan E.A.,University of Sao Paulo | Scotton D.C.,University of Sao Paulo | Ferreira R.R.,University of Sao Paulo | Jorge E.C.,Federal University of Minas Gerais | And 3 more authors.
American Journal of Botany | Year: 2012

Premise of the study: Microsatellite primers were developed for Jatropha curcas (Euphorbiaceae), a tree species with large potential for biofuel production, to investigate its natural genetic diversity and mating system to facilitate the establishment of tree improvement and conservation programs. Methods and Results: Using a protocol for genomic library enrichment, 104 clones containing 195 repeat motifs were identify ed. Primer pairs were developed for 40 microsatellite loci and validated in 41 accessions of J. curcas from six provenances. Nine loci were polymorphic revealing from two to eight alleles per locus, and six primers were able to amplify alleles in the congeners J. podagrica, J. pohliana, and J. gossypifolia, but not in other Euphorbiaceae species, such as Hevea brasiliensis, Manihot esculenta, or Ricinus communis. Conclusions: The primers developed here revealed polymorphic loci that are suitable for genetic diversity and structure, mating system, and gene flow studies in J. curcas, and some congeners. © 2012 Botanical Society of America.


Tarazi R.,University of Sao Paulo | Sebbenn A.M.,Instituto Florestal Of Sao Paulo | Kageyama P.Y.,University of Sao Paulo | Vencovsky R.,University of Sao Paulo
Heredity | Year: 2013

Edge effects may affect the mating system of tropical tree species and reduce the genetic diversity and variance effective size of collected seeds at the boundaries of forest fragments because of a reduction in the density of reproductive trees, neighbour size and changes in the behaviour of pollinators. Here, edge effects on the genetic diversity, mating system and pollen pool of the insect-pollinated Neotropical tree Copaifera langsdorffii were investigated using eight microsatellite loci. Open-pollinated seeds were collected from 17 seed trees within continuous savannah woodland (SW) and were compared with seeds from 11 seed trees at the edge of the savannah remnant. Seeds collected from the SW had significantly higher heterozygosity levels (H o =0.780; H e =0.831) than seeds from the edge (H o =0.702; H e =0.800). The multilocus outcrossing rate was significantly higher in the SW (t m =0.859) than in the edge (t m =0.759). Pollen pool differentiation was significant, however, it did not differ between the SW (=0.105) and the edge (=0.135). The variance effective size within the progenies was significantly higher in the SW (N e =2.65) than at the edge (N e =2.30). The number of seed trees to retain the reference variance effective size of 500 was 189 at the SW and 217 at the edge. Therefore, it is preferable that seed harvesting for conservation and environmental restoration strategies be conducted in the SW, where genetic diversity and variance effective size within progenies are higher. © 2013 Macmillan Publishers Limited All rights reserved.


Tarazi R.,University of Sao Paulo | Sebbenn A.M.,Instituto Florestal Of Sao Paulo | Kageyama P.Y.,University of Sao Paulo | Vencovsky R.,University of Sao Paulo
Ecology and Evolution | Year: 2013

Savannas are highly diverse and dynamic environments that can shift to forest formations due to protection policies. Long-distance dispersal may shape the genetic structure of these new closed forest formations. We analyzed eight microsatellite loci using a single-time approach to understand contemporary pollen and effective seed dispersal of the tropical tree, Copaifera langsdorffii Desf. (Fabaceae), occurring in a Brazilian fire- and livestock-protected savanna. We sampled all adult trees found within a 10.24 ha permanent plot, young trees within a subplot of 1.44 ha and open-pollinated seeds. We detected a very high level of genetic diversity among the three generations in the studied plot. Parentage analysis revealed high pollen immigration rate (0.64) and a mean contemporary pollen dispersal distance of 74 m. In addition, half-sib production was 1.8 times higher than full-sibs in significant higher distances, indicating foraging activity preference for different trees at long distances. There was a significant and negative correlation between diameter at breast height (DBH) of the pollen donor with the number of seeds (r = -0.640, P-value = 0.032), suggesting that pollen donor trees with a higher DBH produce less seeds. The mean distance of realized seed dispersal (recruitment kernel) was 135 m due to the large home range dispersers (birds and mammals) in the area. The small magnitude of spatial genetic structure found in young trees may be a consequence of overlapping seed shadows and increased tree density. Our results show the positive side of closed canopy expansion, where animal activities regarding pollination and seed dispersal are extremely high.© 2013 The Authors. Ecology and Evolution.


de Lacerda A.E.B.,EMBRAPA - Empresa Brasileira de Pesquisa Agropecuária | Nimmo E.R.,University of Sao Paulo | Sebbenn A.M.,Instituto Florestal Of Sao Paulo
Forest Science | Year: 2013

Although selective logging is a common practice for timber production in the Brazilian Amazon, very little is known about its impacts on genetic diversity and demography of the harvested species. This study explores the sustainability of current forest management systems in the Brazilian Amazon by modeling harvesting cycles and examining the impacts on the genetic diversity and demography of the highly valued species Hymenaea courbaril. Using extensive field data, we introduced a two-step modeling procedure for EcoGene software that allowed us to identify optimal felling cycles that were later used for testing and defining sustainable logging parameters. The results show that logging cycles for H. courbaril should be approximately of 110 years, as opposed to the 30-year cycle currently used in Brazil, and harvesting levels should consider a combination of larger minimum cutting diameters (75-100 cm) and lower logging intensities (10-50%). We conclude that current practices in Brazil (30-year cycle, logging intensities of 90%, and minimum cutting diameters of 50 cm) are unsustainable for H. courbaril and that the current practice of using general logging prescriptions for all species does not deliver sustainable forest management in the Amazon. Brazilian forest harvesting regulations need to move toward species-specific prescriptions to ensure real sustainability in the long term. © 2013 by the Society of American Foresters.


Tambarussi E.V.,University of Sao Paulo | Vencovsky R.,University of Sao Paulo | Freitas M.L.M.,Instituto Florestal Of Sao Paulo | Sebbenn A.M.,Instituto Florestal Of Sao Paulo
Genetics and Molecular Research | Year: 2013

Cariniana legalis is one of the largest tropical trees with a wide distribution in the Brazilian Atlantic rainforest. We investigated the Mendelian inheritance, genetic linkage, and genotypic disequilibrium at seven microsatellite loci specifically isolated for C. legalis, and at two previously developed heterologous microsatellite loci. Forty to 100 open-pollinated seeds were collected from 22 seed-trees in two populations. Using the Bonferroni correction, no remarkable deviations from the expected Mendelian segregation, linkage, or genotypic disequilibrium were detected in the nine loci studied. Only 3.7% of the tests were significant for investigations of the Mendelian proportions. On the other hand, only 2.8% of tests for linkage detection showed significance. In addition, among all pairwise tests used for investigating linkage disequilibrium, significance was found in 9.7% of the locus pairs. Our results show clear evidence that the nine simple sequence repeat loci can be used without restriction in genetic diversity, mating system, and parentage analyses. © FUNPEC-RP.


Feres J.M.,University of Sao Paulo | Sebbenn A.M.,Instituto Florestal Of Sao Paulo | Guidugli M.C.,University of Sao Paulo | Mestriner M.A.,University of Sao Paulo | And 2 more authors.
Conservation Genetics | Year: 2012

For many tree species, mating system analyses have indicated potential variations in the selfing rate and paternity correlation among fruits within individuals, among individuals within populations, among populations, and from one flowering event to another. In this study, we used eight microsatellite markers to investigate mating systems at two hierarchical levels (fruits within individuals and individuals within populations) for the insect pollinated Neotropical tree Tabebuia roseo-alba. We found that T. roseo-alba has a mixed mating system with predominantly outcrossed mating. The outcrossing rates at the population level were similar across two T. roseo-alba populations; however, the rates varied considerably among individuals within populations. The correlated paternity results at different hierarchical levels showed that there is a high probability of shared paternal parentage when comparing seeds within fruits and among fruits within plants and full-sibs occur in much higher proportion within fruits than among fruits. Significant levels of fixation index were found in both populations and biparental inbreeding is believed to be the main cause of the observed inbreeding. The number of pollen donors contributing to mating was low. Furthermore, open-pollinated seeds varied according to relatedness, including half-sibs, full-sibs, self-sibs and self-half-sibs. In both populations, the effective population size within a family (seed-tree and its offspring) was lower than expected for panmictic populations. Thus, seeds for ex situ conservation genetics, progeny tests and reforestation must be collected from a large number of seed-trees to guarantee an adequate effective population in the sample. © 2011 Springer Science+Business Media B.V.


Sobral M.,DCNAT | Grippa C.R.,Socioambiental Consultores Associados | Souza M.C.,Jardim Botanico do Rio de Janeiro | Aguiar O.T.,Instituto Florestal Of Sao Paulo | And 2 more authors.
Phytotaxa | Year: 2012

Fourteen new Myrtaceae are described, illustrated and compared to related species from Brazil: Calyptranthes boanova, C. curta, C. detecta, C. maritima, Eugenia culta, E. rotula, E. serraegrandis, E. unana, Myrcia clavata, M. lascada, M. teimosa, M. truncata, Myrcianthes riparia and Myrciaria alagoana. Calyptranthes boanova is related to C. grandiflora, but presents sessile, glabrous leaves; C. curta is related to C. dichotoma, differing through the small inflorescences; C. detecta is close to C. tricona, but has largest leaves and inflorescences; C. maritima is related to C. strigipes, but presents larger leaves and inflorescences and smaller flowers; Eugenia culta is related to E. sprengelii, but presents verticillate leaves and longer pedicels; E. rotula is distinct from all Brazilian species by its small rounded leaves; E. serraegrandis is related to E. platyphylla, differing in its larger leaves and densely pilose flowers; E. unana is close to E. stictopetala, but the leaves are wider and more laxly venose and the flowers present larger calyx lobes; Myrcia clavata is close to M. riodocensis, but has wider leaves and pentamerous flowers; M. lascada is related to M. palustris, from which it differs by the larger leaves and three to five-flowered inflorescences; M. teimosa is related to M. eximia, differing through shorter inflorescences and four-celled ovaries; M. truncata is distinguished from all Brazilian species through its basally truncate leaves; Myrcianthes riparia is close to M. pedersenii, but has glabrous leaves and flowers, tetramerous flowers and smaller, purple fruits, and Myrciaria alagoana is related to M. glomerata, but has larger petioles and glabrous and caudate leaves. Calyptranthes boanova, Eugenia serraegrandis, E. unana, Myrcia lascada, M. teimosa and M. truncata were collected in the southern Bahian rainforests; Calyptranthes curta and C. maritima are from the coastal rainforests of the southeastern state of São Paulo; C. detecta is from the rainforests of southeastern Minas Gerais; Eugenia culta was collected along the Atlantic Rainforest (Mata Atlântica) domain in the southeastern Brazilian states of Espírito Santo and Minas Gerais; Eugenia rotula was collected in rocky fields from the Bahian hinterland; Myrcia clavata and Myrciaria alagoana are from the Atlantic Rainforest of the northeastern state of Alagoas, and Myrcianthes riparia grows in riverine habitats in the highlands of the southern Brazilian states of Rio Grande do Sul and Santa Catarina. Additionally, there are proposed the rehabilitation of the name Eugenia astringens and the new name Myrcia neopauciflora, based on Aulomyrcia pauciflora. © 2012 Magnolia Press.


Cupressus lusitanica has a relatively low potential for fostering colonization of native species beneath the forest canopy. However, following the clearcut of a Cupressus lusitanica plantation in the State Forest of Avaré (SFA), southeastern Brazil, a vigorous regeneration of Atlantic forest tree and shrub species was observed. We evaluated the passive restoration of this site by comparing its regenerating vegetation to the vegetation established in man-made gaps in Atlantic forest in the State Park of Cantareira (SPC), southeastern Brazil. The frequency distribution of dispersal syndromes for species and the rate of reduction in abundance of pioneer species in a rank/abundance plot did not differ between the two areas. The rarefaction curves for species richness and diversity of the SPC fall below the corresponding curves of the SFA. The proportions of non-pioneer species and of individuals of non-pioneer species were greater in the SFA. The frequency distribution of dispersal syndromes for individuals differed between the two areas due mainly to a more conspicuous predominance of zoochory in the SFA. The rate of reduction in abundance of non-pioneer species in a rank/abundance plot was smaller in the SFA. We concluded that passive restoration may successfully recover native vegetation attributes following the clearcut of forest plantations without conspicuous regeneration of native species beneath the forest canopy. However, this phenomenon may be influenced by particular properties of the forest species, logging practices and faunal seed dispersal integrity. © 2016, Universidade Federal de Santa Maria. All Rights Reserved.


Moraes M.L.T.D.,São Paulo State University | Sebbenn A.M.,Instituto Florestal Of Sao Paulo
Biotropica | Year: 2011

This case study examines the pollen dispersal distance, pollen dispersal patterns and intra-family genetic structure for isolated trees in pastures of the bat-pollinated Neotropical tree species Hymenaea stigonocarpa using six microsatellite loci and parentage analysis. The sampling included 28 grouped trees (referred to as the population) and six isolated trees in pastureland along a highway in Mato Grosso do Sul State, Brazil. From the population, we sampled 137 seeds from 12 seed-trees, and from the isolated trees, we sampled 34 seeds from two seed-trees. The results showed that pollen was dispersed over long distances (reaching 7353m) and therefore the spatially isolated trees were not reproductively isolated. The pollen immigration rate in the population was also high (31%). Isolated trees presented a higher selfing rate (s=26%) than trees in the population (s=12%), suggesting that the spatial isolation of the trees increased selfing. However, selfing was responsible for only 30 percent of the inbreeding in offspring and mating among relatives was 70 percent. In the population, excluding selfing, ca 72 percent of the pollen was dispersed over distances <1000m (average: 860m). For the two isolated seed-trees, excluding selfing, the average pollen dispersal distance was 5229m. The results demonstrate that although pollen can be dispersed over long distances for H. stigonocarpa isolated trees, a high percentage of pollen comes from the same tree (selfing) and mating was correlated. Consequently, seeds must be collected from a large number of seed-trees for conservation purposes. © 2010 The Author(s). Journal compilation © 2010 by The Association for Tropical Biology and Conservation.

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