Evaluation of Red Clover Populations Selected for Persistence and Dry Matter Yield in Rio Grande Do Sul, Brasil

Red clover is one of the most important temperate legume species and it is used to alleviate the lack of forage in natural grasslands during the cool season in Rio Gra do Sul, Brasil. However, the lack of persistence presented by this species has not allowed its full utilization. Hence, a breeding program was started to select plants with more persistence and with good dry matter (DM) yield. This work was carried out at the “Estação Experimental Agronômica”, Universidade Federal do Rio Grande do Sul. Three selected red clover populations were evaluated in relation to the best available commercial check, cv. Quiñqueli, in a mixture with annual ryegrass. There were significant differences among the populations in relation to persistence and DM yield of its components. Two of the selected populations were more persistent than the check after the first season of growth, pointing to the possibility of making progress in this trait while maintaining the yield potential

Biomassa ensilável de genótipos precoces de cevada na entressafra de grãos de verão e inverno no Rio Grande do Sul.

Adoção de cultivares de soja e milho mais precoces e o risco de geadas no cultivo de trigo possibilita outra safra entre os cultivos de verão e inverno, denominada de entressafra

Variabilidade genética de caracteres forrageiros em acessos do gênero Paspalum em diferentes ambientes

The objective of this study was to determine the genetic variability among accessions of different species of Genus Paspalum, seeking to understand the dynamics of expression of characters with forage interest in different locations and crop years. The experiments were conducted in randomized blocks with three replications and plots consisting of five accessions of P. nicorae two of P. guenoraum and more to cultivate Pensacola (P. notatum) used as a control. The accessions show high genetic variability in forage traits of interest, with a decisive effect on the expression of the genotype versus environment interaction.O objetivo do trabalho foi determinar a variabilidade genética entre acessos de diferentes espécies de Paspalum e a expressão de caracteres de interesse forrageiro em distintos locais e anos de cultivo. Os experimentos foram conduzidos em delineamento experimental de blocos ao acaso com três repetições com parcelas compostas por cinco acessos de P. nicorae, dois de P. guenoraum e mais a cultivar Pensacola (P. notatum) utilizada como testemunha. Os acessos avaliados apresentaram variabilidade genética em caracteres de interesse forrageiro com efeitos na interação genótipo x ambiente. A produção de matéria seca total e de folhas foram os caracteres que mais contribuíram para a detecção da variabilidade genética observada independentemente do ano de avaliação

Associações entre caracteres forrageiros de espécies do gênero Paspalum

The native accessions from Rio Grande do Sul of Paspalum nicorae, “28B”, “26A”, “28C”, “26D” and “28E” and the accessions “Azulão” and “Baio” of Paspalum guenoarum were evaluated in order to measure the association of leaves dry matter yield with other traits of interest on these apomictic plants, tested in different years and locations. A completely randomized block design with three replications in two physiographically distinct regions was used. The evaluations of the agronomic traits was made under cuts. Total dry matter yield, leaves dry matter, stems dry matter, leaf: stem ratio, harvest index and number of tillers were determined. Similar correlations were obtained in both locations, with leaves dry matter yield showing the largest magnitude, affecting directly the total dry matter yield. Correlation analysis showed that overall the leaves dry matter and stems dry matter yield form a high and positive correlation affecting the total dry matter yield. The total dry matter yield can be directly used for selection of genotypes in the genus Paspalum.Os acessos nativos do Rio Grande do Sul, “28B”, “26A”, “28C”, “26D” e “28E” de Paspalum nicorae e os ecótipos “Azulão” e “Baio” de Paspalum guenoarum foram avaliados com o objetivo de dimensionar a intensidade de associação da produção de matéria seca de folha com outros caracteres de interesse forrageiros nessas espécies apomíticas, testadas em diferentes anos e locais. O delineamento adotado foi o de blocos casualizados com três repetições em duas regiões fisiograficamente distintas. As avaliações foram realizadas por meio de cortes. As variáveis avaliadas foram a produção de matéria seca total, matéria seca de folhas, matéria seca de colmo, relação folha:colmo, índice de colheita e o número de afilhos. Correlações similares foram obtidas nos dois locais, qualificando a matéria seca de folhas como a de maior magnitude na relação direta e positiva à materia seca total. A análise de correlação geral demonstrou que a matéria seca de folhas e matéria seca de colmo forma alta correlação positiva para o incremento da matéria seca total. A produção da matéria seca total pode ser utilizada diretamente para seleção de genotipos em espécies do gênero Paspalum

Multivariate analysis reveals genetic diversity in Paspalum notatum Flügge

The objective of this study was to evaluate 94 Paspalum notatum genotypes over two growing seasons to estimate genetic dissimilarity through agronomic traits and the distance between genotypes. This information is used to create an ideotype from the best averages obtained for the set of characteristics evaluated. Seven apomitic, three sexual, and 81 hybrid genotypes were compared with native genotypes “André da Rocha”, “Bagual”, and cultivar “Pensacola” as controls. There is genetic variability in P. notatum for the studied characteristics, and distinct genotypes with superior characteristics can be used in new combinations between apomictic and sexual plants to obtain hybrids. The characters with the greatest relative contribution to the dissimilarity between the genotypes were tiller density, stem dry mass, and leaf dry mass yield. Thus, these characteristics are suitable criteria to infer genetic distance studies in P. notatum. The selection index based on the ideotype is an auxiliary tool in the breeding process. The ideotype must be based on characteristics of interest according to the objective of the breeding program, as well as on the breeder’s prior knowledge in relation to culture

Characterization and genetic diversity in Paspalum notatum Flügge accessions: Morphological and geographical distance

The objective of this work was to describe morphology and grouping of Paspalum notatum accessions, based on multicategorical data which discards the redundant variables for quantification of genetic diversity. We also tested the hypothesis that geographical distance was correlated with morphological divergence. In our study, multivariate analyzes successfully demonstrated the geographic and morphological variability of the P. notatum accessions characterized. Many of these evaluated accessions can be included in future genetic improvement programs. Based on two methodologies for discarding variables, it was possible to identify the potentially important morphological characteristics from genetic diversity studies and characterize new accessions aimed at improving forage and seed production. The methodologies used to discard variables are biometric tools that can be used successfully in future plant breeding programs, especially when a large number of traits and accessions are being evaluated. Although significant, geographic distance had a low association with morphological traits. This indicated the need to use other characteristics, such as forage and seed yield, in addition to molecular analysis. Our analyzes showed genetic variability in P. notatum for all the characteristics studied

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

Utilização estratégica de gramíneas anuais de verão para vazio forrageiro outonal e cobertura de solo.

Culturas como milheto e sorgos são espécies de crescimento intensivo, altamente produtivos e de elevado valor nutritivo. Geralmente são estabelecidos em sucessão aos cereais de inverno e pastagens anuais, muito importantes para sistemas de produção intensivos principalmente para bovinos confinados, vacas leiteiras, novilhas e terneiras de reposição na região sul-brasileira. Na região tropical brasileira é cultivado na safrinha e como cobertura de solo

Ambiguidade do cuidado na vivência do consumidor de drogas

RESUMO Objetivo Compreender a percepção de usuários de um Centro de Atenção Psicossocial sobre o cuidado no contexto do consumo de drogas. Métodos Estudo fundamentado na Fenomenologia de Maurice Merleau-Ponty, desenvolvido no segundo semestre do ano de 2015. Foram realizados dois encontros de Grupo Focal, com dez usuários de um Centro de Atenção Psicossocial Álcool e outras Drogas. Os dados foram submetidos à técnica Analítica da Ambiguidade. Resultados O consumo de drogas ora proporciona ao consumidor sensações de prazer, ora contribui para a ocorrência de prejuízos biopsicossociais e/ou novas possibilidades de relação com a droga. Conclusões O consumo de drogas constitui-se em um processo ambíguo, que corresponde à percepção de diferentes perfis de cuidado na relação do consumidor com a droga. Cabe aos profissionais de saúde reconhecer as diversas possibilidades de cuidado e favorecer a construção de projetos terapêuticos baseados na escuta e respeito às necessidades dos consumidores de drogas