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The role of natural selection in shaping spatial patterns of genetic diversity in the Neotropics is still poorly understood. Here, we perform a genome scan with 24,751 probes targeting 11,026 loci in two Neotropical Bignoniaceae tree species: Handroanthus serratifolius from the seasonally dry tropical forest (SDTF) and Tabebuia aurea from savannas, and compared with the population genomics of H. impetiginosus from SDTF. OutFLANK detected 29 loci in 20 genes with selection signal in H. serratifolius and no loci in T. aurea. Using BayPass, we found evidence of selection in 335 loci in 312 genes in H. serratifolius, 101 loci in 92 genes in T. aurea, and 448 loci in 416 genes in H. impetiginosus. All approaches evidenced several genes affecting plant response to environmental stress and primary metabolic processes. The three species shared no SNPs with selection signal, but we found SNPs affecting the same gene in pair of species. Handroanthus serratifolius showed differences in allele frequencies at SNPs with selection signal among ecosystems, mainly between Caatinga/Cerrado and Atlantic Forest, while H. impetiginosus had one allele fixed across all populations, and T. aurea had similar allele frequency distribution among ecosystems and polymorphism across populations. Taken together, our results indicate that natural selection related to environmental stress shaped the spatial pattern of genetic diversity in the three species. However, the three species have different geographical distribution and niches, which may affect tolerances and adaption, and natural selection may lead to different signatures due to the differences in adaptive landscapes in different niches.

Cassava is the main staple crop in the tropics. It is vegetatively propagated by stem cuttings that maintain superior genotypes, but favors disease accumulation. In this report we present the results of the screening of the progeny and the second generation of the clone UnB 307 for apomixis using microsatellites. A total of 29 plants were screened, representing the maternal plant, its first and second generations, that were left to open pollination. About 20% of the offspring were rated as genetically identical plants. This result confirms the facultative apomictic nature of cassava, with high environment effect.

Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-27T11:22:35Z No. of bitstreams: 0Bitstream added on 2014-05-27T14:33:39Z : No. of bitstreams: 1 2-s2.0-34548281223.pdf: 461764 bytes, checksum: 7d133998a53728b64aee7dc2c1dc3aba (MD5) Made available in DSpace on 2014-05-27T11:22:35Z (GMT). No. of bitstreams: 0 Previous issue date: 2007-09-03 Blastocerus dichotomus, the marsh deer, is the largest Brazilian Cervidae species. The species is endangered because of hunting and loss of its natural habitat, i.e., flood plain areas, because of hydroelectric power station construction and agricultural land expansion. In the present study, we tested 38 microsatellite loci from four Cervidae species: Odocoileus virginianus (7), Rangifer tarandus (17), Capreolus capreolus (7), and Mazama bororo (7). Eleven loci showed clear amplification, opening a new perspective for the generation of fundamental population genetic data for devising conservation strategies for B. dichotomus. © FUNPEC-RP. Universidade Católica de Brasília, Brasília, DF Núcleo de Pesquisa e Conservação de Cervídeos Departamento de Zootecnia Universidade Estadual Paulista, Jaboticabal, SP EMBRAPA Centro de Pesquisa Agropecuária do Pantanal, Mato Grosso do Sul, MS Núcleo de Pesquisa e Conservação de Cervídeos Departamento de Zootecnia Universidade Estadual Paulista, Jaboticabal, SP

The effects of Brazil's political crisis on science funding necessary for biodiversity conservation are likely to be global. Brazil is not only the world's most biodiverse nation, it is responsible for the greater part of the Amazon forest, which regulates the climate and provides rain to much of southern South America. Brazil was a world leader in satellite monitoring of land-use change, in-situ biodiversity monitoring, reduction in tropical-forest deforestation, protection of indigenous lands, and a model for other developing nations. Coordinated public responses will be necessary to prevent special-interest groups from using the political crisis to weaken science funding, environmental legislation and law enforcement. © 2018 Magnusson, Grelle, Marques, Rocha, Dias, Fontana, Bergallo, Overbeck, Vale, Tomas, Cerqueira, Collevatti, Pillar, Malabarba, Lins-e-Silva, Neckel-Oliveira, Martinelli, Akama, Rodrigues, Silveira, Scariot and Fernandes.