“Screening” precoce quanto à tolerância ao frio no melhoramento de cana-de-açúcar

The objective of this work was to evaluate the efficiency of early screening in the selection of sugarcane (Saccharum spp.) families for cold tolerance in a controlled environment. Fourteen sugarcane families were evaluated for leaf damage and chlorophyll content, in a controlled environment and in the field, after cold stress. The variance components and genotypic values of the families were estimated via REML/BLUP, as well as the genetic correlations between variables and environments. The heritabilities in the narrow sense and for family averages showed values above 0.23 and 0.76, respectively, and a genetic coefficient of variation above 13%, which confirmis the existence of variability and enables selection in both environments. The genetic correlations ranged from 0.59 to 0.88 and were significant for all combinations of variables and environments. The average coincidence index for the families between environments was 60% for the selected group and 85% for the unselected group. The early screening in the first stages of selection is efficient in breeding for cold tolerance in sugarcane families.O objetivo deste trabalho foi avaliar a eficiência do screening precoce na seleção de famílias de cana-de-açúcar (Saccharum spp.) quanto à tolerância ao frio em ambiente controlado. Avaliaram-se 14 famílias de cana-de-açúcar quanto ao dano foliar e ao teor de clorofila, em ambiente controlado e em campo, após estresse por frio. Estimaram-se os componentes de variância e os valores genotípicos das famílias via REML/BLUP, bem como as correlações genéticas entre variáveis e ambientes. As herdabilidades no sentido restrito e para médias de famílias apresentaram valores superiores a 0,23 e 0,76, respectivamente, com coeficiente de variação genético superior a 13%, o que confirma existência de variabilidade e torna possível a seleção em ambos os ambientes. As correlações genéticas variaram de 0,59 a 0,88 e foram significativas para todas as combinações de variáveis e ambientes. O índice de coincidência médio para as famílias entre ambientes foi de 60% para o grupo selecionado e de 85% para o grupo não selecionado. O “screening” precoce, nas primeiras fases de seleção, é eficiente no melhoramento genético para tolerância ao frio em famílias de cana-de-açúcar

INFLUÊNCIA DO PERFIL DO DARK TRIAD DOS ACADÊMICOS DO CURSO DE CIÊNCIAS CONTÁBEIS NA QUALIDADE DAS NOTAS EXPLICATIVAS

O objetivo desta pesquisa é analisar a influência dos traços de personalidade do Dark Triad dos acadêmicos do curso de ciências contábeis na divulgação das informações financeiras apresentadas nas notas explicativas. A amostra utilizada no estudo foi constituída por 100 alunos do curso de ciências contábeis vespertino e noturno do sexto ao oitavo período da Universidade Federal do Espirito Santo (UFES). Em relação aos procedimentos de coleta de dados, foi feita a aplicação do questionário Short Dark Triad (SD3) desenvolvido por Delroy Paulhus e Williams (2002) sobre as três personalidades dessa tríade (psicopatia, narcisismo e maquiavelismo) com a inclusão de perguntas feitas com base no CPC 26 relacionadas as notas explicativas no período de tempo de nove dias contendo um total de 27 questões objetivas e, foi feita uma análise fatorial exploratório. Como principais resultados foram identificados que 14 fatores explicariam mais de 80% da variância do modelo, enquanto 8 fatores explicariam pouco mais de 61% se a decisão para tomada de decisão com base na raiz latente (autovalor). Assim, conclui-se que o intervalo de autovalores é que define a utilização de uma maior ou menor quantidade de fatores que consigam explicar o comportamento dos estudante

Genome-wide signatures of complex introgression and adaptive evolution in the big cats.

The great cats of the genus Panthera comprise a recent radiation whose evolutionary history is poorly understood. Their rapid diversification poses challenges to resolving their phylogeny while offering opportunities to investigate the historical dynamics of adaptive divergence. We report the sequence, de novo assembly, and annotation of the jaguar (Panthera onca) genome, a novel genome sequence for the leopard (Panthera pardus), and comparative analyses encompassing all living Panthera species. Demographic reconstructions indicated that all of these species have experienced variable episodes of population decline during the Pleistocene, ultimately leading to small effective sizes in present-day genomes. We observed pervasive genealogical discordance across Panthera genomes, caused by both incomplete lineage sorting and complex patterns of historical interspecific hybridization. We identified multiple signatures of species-specific positive selection, affecting genes involved in craniofacial and limb development, protein metabolism, hypoxia, reproduction, pigmentation, and sensory perception. There was remarkable concordance in pathways enriched in genomic segments implicated in interspecies introgression and in positive selection, suggesting that these processes were connected. We tested this hypothesis by developing exome capture probes targeting ~19,000 Panthera genes and applying them to 30 wild-caught jaguars. We found at least two genes (DOCK3 and COL4A5, both related to optic nerve development) bearing significant signatures of interspecies introgression and within-species positive selection. These findings indicate that post-speciation admixture has contributed genetic material that facilitated the adaptive evolution of big cat lineages

Local hydrological conditions influence tree diversity and composition across the Amazon basin

Tree diversity and composition in Amazonia are known to be strongly determined by the water supplied by precipitation. Nevertheless, within the same climatic regime, water availability is modulated by local topography and soil characteristics (hereafter referred to as local hydrological conditions), varying from saturated and poorly drained to well-drained and potentially dry areas. While these conditions may be expected to influence species distribution, the impacts of local hydrological conditions on tree diversity and composition remain poorly understood at the whole Amazon basin scale. Using a dataset of 443 1-ha non-flooded forest plots distributed across the basin, we investigate how local hydrological conditions influence 1) tree alpha diversity, 2) the community-weighted wood density mean (CWM-wd) – a proxy for hydraulic resistance and 3) tree species composition. We find that the effect of local hydrological conditions on tree diversity depends on climate, being more evident in wetter forests, where diversity increases towards locations with well-drained soils. CWM-wd increased towards better drained soils in Southern and Western Amazonia. Tree species composition changed along local soil hydrological gradients in Central-Eastern, Western and Southern Amazonia, and those changes were correlated with changes in the mean wood density of plots. Our results suggest that local hydrological gradients filter species, influencing the diversity and composition of Amazonian forests. Overall, this study shows that the effect of local hydrological conditions is pervasive, extending over wide Amazonian regions, and reinforces the importance of accounting for local topography and hydrology to better understand the likely response and resilience of forests to increased frequency of extreme climate events and rising temperatures

Geography and ecology shape the phylogenetic composition of Amazonian tree communities

Aim: Amazonia hosts more tree species from numerous evolutionary lineages, both young and ancient, than any other biogeographic region. Previous studies have shown that tree lineages colonized multiple edaphic environments and dispersed widely across Amazonia, leading to a hypothesis, which we test, that lineages should not be strongly associated with either geographic regions or edaphic forest types. Location: Amazonia. Taxon: Angiosperms (Magnoliids; Monocots; Eudicots). Methods: Data for the abundance of 5082 tree species in 1989 plots were combined with a mega-phylogeny. We applied evolutionary ordination to assess how phylogenetic composition varies across Amazonia. We used variation partitioning and Moran\u27s eigenvector maps (MEM) to test and quantify the separate and joint contributions of spatial and environmental variables to explain the phylogenetic composition of plots. We tested the indicator value of lineages for geographic regions and edaphic forest types and mapped associations onto the phylogeny. Results: In the terra firme and várzea forest types, the phylogenetic composition varies by geographic region, but the igapó and white-sand forest types retain a unique evolutionary signature regardless of region. Overall, we find that soil chemistry, climate and topography explain 24% of the variation in phylogenetic composition, with 79% of that variation being spatially structured (R$^{2}$ = 19% overall for combined spatial/environmental effects). The phylogenetic composition also shows substantial spatial patterns not related to the environmental variables we quantified (R$^{2}$ = 28%). A greater number of lineages were significant indicators of geographic regions than forest types. Main Conclusion: Numerous tree lineages, including some ancient ones (>66 Ma), show strong associations with geographic regions and edaphic forest types of Amazonia. This shows that specialization in specific edaphic environments has played a long-standing role in the evolutionary assembly of Amazonian forests. Furthermore, many lineages, even those that have dispersed across Amazonia, dominate within a specific region, likely because of phylogenetically conserved niches for environmental conditions that are prevalent within regions

Geography and ecology shape the phylogenetic composition of Amazonian tree communities

AimAmazonia hosts more tree species from numerous evolutionary lineages, both young and ancient, than any other biogeographic region. Previous studies have shown that tree lineages colonized multiple edaphic environments and dispersed widely across Amazonia, leading to a hypothesis, which we test, that lineages should not be strongly associated with either geographic regions or edaphic forest types.LocationAmazonia.TaxonAngiosperms (Magnoliids; Monocots; Eudicots).MethodsData for the abundance of 5082 tree species in 1989 plots were combined with a mega-phylogeny. We applied evolutionary ordination to assess how phylogenetic composition varies across Amazonia. We used variation partitioning and Moran's eigenvector maps (MEM) to test and quantify the separate and joint contributions of spatial and environmental variables to explain the phylogenetic composition of plots. We tested the indicator value of lineages for geographic regions and edaphic forest types and mapped associations onto the phylogeny.ResultsIn the terra firme and várzea forest types, the phylogenetic composition varies by geographic region, but the igapó and white-sand forest types retain a unique evolutionary signature regardless of region. Overall, we find that soil chemistry, climate and topography explain 24% of the variation in phylogenetic composition, with 79% of that variation being spatially structured (R2 = 19% overall for combined spatial/environmental effects). The phylogenetic composition also shows substantial spatial patterns not related to the environmental variables we quantified (R2 = 28%). A greater number of lineages were significant indicators of geographic regions than forest types.Main ConclusionNumerous tree lineages, including some ancient ones (>66 Ma), show strong associations with geographic regions and edaphic forest types of Amazonia. This shows that specialization in specific edaphic environments has played a long-standing role in the evolutionary assembly of Amazonian forests. Furthermore, many lineages, even those that have dispersed across Amazonia, dominate within a specific region, likely because of phylogenetically conserved niches for environmental conditions that are prevalent within regions