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.(AU)

Interactive effects of digestible protein levels on thermal and physical stress responses in Nile tilapia

The effects of dietary digestible protein (DP) levels (22, 26, 29, 32, and 34%) and different stressors (cold-induced stress, CIS; heat/dissolved oxygen-induced stress, HDOIS; transport-induced stress, TIS; and size-sorting-induced stress, SSIS) on hemato-biochemical parameters were evaluated. Four hundred and forty Nile tilapia fingerlings were distributed into 40-250 L aquaria and fed experimental diets for 110 days, and fed each of the five experimental diets, that were randomly distributed to eight replicates per treatment. Then, different groups of fish were subjected to one type of stress. Groups of 40 fish were used on CIS (17 °C), HDOIS (32 °C), and TIS (4 h), and a group of 140 fish on SSIS (15 min air exposure and 60 s handling). There was no effect on hemato-biochemical profile when DP levels were compared, neither before nor after stress; however, there was a significant stress effect. Digestible protein did not mitigate stress response under SSIS and CIS; lymphopenia and neutrophilia were the main cell-mediated immune response; dietary 22 and 26% DP impaired oxygenation on SSIS and TIS; fish under HDOIS and SSIS demanded more energy using triglycerides as an energy source; the diet formulated to contain 22% DP was not adequate to keep homeostasis under temperature stress. Cluster analysis showed that, for DP levels below the requirement for growth, SSIS and CIS were considered the most stressful conditions. At 34% DP level, HDOIS response was comparable to that of non-stressing conditions.(AU)

Sustainability indicators for Brazilian dairy livestock: the perception of professionals in the sector

The objective of this study was to analyze the perceptions of professionals in relation to the importance of indicators used to assess the sustainability of Brazilian dairy cattle. A survey method was used through a questionnaire. The target audience was professionals related to dairy cattle: researchers, professors, consultants, farmers, and other professionals. The total number of respondents to the survey was 347. Cluster analysis resulted in the formation of four distinct groups: G1 ("Holistic"), participants agreed that all indicators are very important or, at least, important; G2 ("Technician") considered the indicators important and desirable, except for some environmental indicators which were assessed as non-priority and expendable; G3 ("Socioenvironmentalist") assessed the indicators as desirable, but environmental indicators received more importance; and G4 ("Skeptic") generally believed that indicators were non-priority and expendable. The groups showed significant differences in relation to knowledge about technical, economic, social, and environmental aspects of dairy cattle. More than 60% of professionals consider milk production per area, reproductive index, production costs, profit from the activity, milk quality, quality of life of the producer and employees, succession, protection of water courses, and soil management as very important indicators of the sustainability of dairy cattle. On the other hand, important environmental indicators such as emissions of gases and substances, energy use, nutrient balance, and land use were neglected by most respondents. These results can help select and implement policies and strategies for decision making, aiming at producing milk in a more sustainable way.(AU)

Meat sheep farming systems according to economic and productive indicators: A case study in Southern Brazil

This study aimed to characterize 24 representative sheep production farms from five mesoregions in the state of Paraná, Southern Brazil, so that economic and productive improvement strategies could be proposed. The representative farms for each region were defined at meetings with sheep farmers and technicians via the rapid appraisal methodology and represent 65% of the state's flock. The information of each representative farm was collected between March 2015 and February 2016. Principal component analysis was used to verify the relationships among the different variables that characterized the farms. These characteristics were: number of ewes (V1), total cost per kilogram of revenue-generating product (V2), feeding costs (V3), labor costs (V4), facility and equipment depreciation costs (V5), and gross margin in the production cycle (V6). Cluster analysis was performed, resulting in three distinct groups: one including eight, another seven, and the third, nine farms. The results aided in classifying the farms into groups with similar characteristics, such as production scale, reproductive efficiency, technical and managerial control, appreciation of cooperatives, and availability of continuous technical assistance. The production scale, reproductive and productive efficiency, adoption of technologies, and cooperative organizational structure can be emphasized as positive performance benchmarks and were the most important aspects to achieve positive economic results.

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.

Choice of non-linear models to determine the growth curve of meat-type quail / Escolha de modelos não-lineares para determinar a curva de crescimento de codornas de corte

The objective of this study was to compare non-linear models fitted to the growth curves of quail to determine which model best describes their growth and check the similarity between models by analyzing parameter estimates.Weight and age data of meat-type European quail (Coturnix coturnix coturnix) of three lines were used, from an experiment in a 2 × 4 factorial arrangement in a completely randomized design, consisting of two metabolizable energy levels, four crude protein levels and six replicates. The non-linear Brody, Von Bertalanffy, Richards, Logistic and Gompertz models were used. To choose the best model, the Adjusted Coefficient of Determination, Convergence Rate, Residual Mean Square, Durbin-Watson Test, Akaike Information Criterion and Bayesian Information Criterion were applied as goodness-of-fit indicators. Cluster analysis was performed to check the similarity between models based on the mean parameter estimates. Among the studied models, Richards was the most suitable to describe the growth curves. The Logistic and Richards models were considered similar in the analysis with no distinction of lines as well as in the analyses of Lines 1, 2 and 3.(AU)

Objetivou-se, neste estudo, comparar modelos não lineares ajustados às curvas de crescimento de codornas para determinar qual modelo que melhor descreve o crescimento de codornas e verificar a similaridade dos modelos analisando as estimativas dos parâmetros. Para as análises foram utilizados os dados peso e idade de codornas européias de corte (Coturnix coturnix coturnix) proveniente de três linhagens, em um esquema fatorial 2x4, instalado em um delineamento inteiramente casualizado, com dois níveis de energia metabolizável e quatro níveis de proteína bruta, com seis repetições. Os modelos não lineares utilizados foram: Brody, Von Bertalanffy, Richards, Logístico e Gompertz. Para a escolha do melhor modelo utilizou-se o Coeficiente de Determinação Ajustado, o Percentual de Convergência, o Quadrado Médio do Resíduo, o Teste de Durbin-Watson, o Critério de informação Akaike e o Critério de informação Bayesiano como avaliadores da qualidade do ajuste. Utilizou-se a análise de agrupamento para verificar, baseado nas estimativas médias dos parâmetros, a similaridades entre os modelos. Entre os modelos estudados, o Richard foi o mais adequado para descrever as curvas de crescimento. Os modelos Logístico e Richards foram considerados similares nas análises sem distinção de linhagem, bem como nas análises das Linhagem 1, 2 e 3.(AU)

Distribution of Chinese traditional villages and influencing factors for regionalization / Distribuição das aldeias tradicionais chinesas e fatores de influência para a regionalização

ABSTRACT: Traditional Villages (TVs) are typical and representative of the agricultural civilization in millions of Chinese villages. The distribution of TVs shows spatial heterogeneity, based on the complexity and diversity of several influencing factors. In this study, 6,819 Chinese TVs were identified and the influencing factors that affect their distribution were screened in terms of three indicator groups: climatic, geographic, and humanity-related factors. Additionally, the K-means clustering algorithm clustered the TVs into different distribution regions. The quantitative relationships between the dominant influencing factors of different distribution regions were revealed to ensure a lucid understanding of the regional distribution of TVs. The results indicated that 1) climatic factors have the greatest impact on the spatial distribution of TVs, followed by geographic factors, particularly the elevation, and then by human factors, of which ethnic distribution played a relatively important role. 2) Twenty-one TV clustering distributions were obtained, which were classified into eight regions of TV distribution with different dominant influencing factors. Management and protective strategies were formulated based on the attribute analysis of influencing factors in each region. The obtained results delineated homogeneous TV distribution regions via the clustering method to achieve an accurate statistical analysis of the influencing factors. This study proposes a new perspective and reference for managing and protecting the diversity, continuity, and integrity of TVs across administrative regions.

RESUMO: As aldeias tradicionais (TVs) são típicas e representativas da civilização agrícola em milhões de comunidades chinesas. A distribuição das TVs mostra heterogeneidade espacial, baseada na complexidade e diversidade de diversos fatores influenciadores. Neste estudo, 6.819 TVs chinesas foram identificadas e os fatores que influenciam sua distribuição foram analisados em termos de três grupos de indicadores: fatores climáticos, geográficos e relacionados à humanidade. Além disso, o algoritmo de agrupamento K-means agrupou as TVs em diferentes regiões de distribuição. As relações quantitativas entre os fatores de influência dominantes de diferentes regiões de distribuição foram reveladas para garantir uma compreensão lúcida da distribuição regional de TVs. Os resultados indicam que 1) os fatores climáticos têm maior impacto na distribuição espacial das TVs, seguidos dos geográficos, em particular da elevação, e depois dos humanos, nos quais a distribuição étnica teve um papel relativamente importante; 2) foram obtidas as vinte e uma distribuições de agrupamento de TV, as quais foram classificadas em oito regiões de distribuição de TV com diferentes fatores de influência dominante. Estratégias de manejo e proteção foram formuladas com base na análise de atributos dos fatores influenciadores de cada região. Os resultados obtidos delinearam regiões homogêneas de distribuição de TV por meio do método de agrupamento para obter uma análise estatística precisa dos fatores de influência. Este estudo propõe uma nova perspectiva e referência para a gestão e proteção da diversidade, continuidade e integridade das TVs nas regiões administrativas.

Distribution of Chinese traditional villages and influencing factors for regionalization / Distribuição das aldeias tradicionais chinesas e fatores de influência para a regionalização

Traditional Villages (TVs) are typical and representative of the agricultural civilization in millions of Chinese villages. The distribution of TVs shows spatial heterogeneity, based on the complexity and diversity of several influencing factors. In this study, 6,819 Chinese TVs were identified and the influencing factors that affect their distribution were screened in terms of three indicator groups: climatic, geographic, and humanity-related factors. Additionally, the K-means clustering algorithm clustered the TVs into different distribution regions. The quantitative relationships between the dominant influencing factors of different distribution regions were revealed to ensure a lucid understanding of the regional distribution of TVs. The results indicated that 1) climatic factors have the greatest impact on the spatial distribution of TVs, followed by geographic factors, particularly the elevation, and then by human factors, of which ethnic distribution played a relatively important role. 2) Twenty-one TV clustering distributions were obtained, which were classified into eight regions of TV distribution with different dominant influencing factors. Management and protective strategies were formulated based on the attribute analysis of influencing factors in each region. The obtained results delineated homogeneous TV distribution regions via the clustering method to achieve an accurate statistical analysis of the influencing factors. This study proposes a new perspective and reference for managing and protecting the diversity, continuity, and integrity of TVs across administrative regions.(AU)

As aldeias tradicionais (TVs) são típicas e representativas da civilização agrícola em milhões de comunidades chinesas. A distribuição das TVs mostra heterogeneidade espacial, baseada na complexidade e diversidade de diversos fatores influenciadores. Neste estudo, 6.819 TVs chinesas foram identificadas e os fatores que influenciam sua distribuição foram analisados em termos de três grupos de indicadores: fatores climáticos, geográficos e relacionados à humanidade. Além disso, o algoritmo de agrupamento K-means agrupou as TVs em diferentes regiões de distribuição. As relações quantitativas entre os fatores de influência dominantes de diferentes regiões de distribuição foram reveladas para garantir uma compreensão lúcida da distribuição regional de TVs. Os resultados indicam que 1) os fatores climáticos têm maior impacto na distribuição espacial das TVs, seguidos dos geográficos, em particular da elevação, e depois dos humanos, nos quais a distribuição étnica teve um papel relativamente importante; 2) foram obtidas as vinte e uma distribuições de agrupamento de TV, as quais foram classificadas em oito regiões de distribuição de TV com diferentes fatores de influência dominante. Estratégias de manejo e proteção foram formuladas com base na análise de atributos dos fatores influenciadores de cada região. Os resultados obtidos delinearam regiões homogêneas de distribuição de TV por meio do método de agrupamento para obter uma análise estatística precisa dos fatores de influência. Este estudo propõe uma nova perspectiva e referência para a gestão e proteção da diversidade, continuidade e integridade das TVs nas regiões administrativas.(AU)

Soil macrofauna as bioindicator of the recovery of degraded cerrado soil / Macrofauna do solo como bio indicador da recuperação de um solo degradado de cerrado

The construction of the hydroelectric power plant of Ilha Solteira, in state of São Paulo, was initiated in the 1960s, when an average, 8.60 m of soil depth was removed, resulting in a degraded area. A plan for the recovery of the area started in 2005 in Selvíria /MS with the use of plant species adapted to the Cerrado biome. This study aimed to evaluate the soil macrofauna of an area under recovery by using different types of soil cover (1- bare soil (control); 2- native Cerrado vegetation; 3- specie Astronium fraxinifolium; 4- Astronium fraxinifolium + Canavalia ensiformis; 5- Astronium fraxinifolium + Raphanus sativus; 6- Astronium fraxinifolium + Brachiaria decumbens + sewage sludge). Soil macrofauna was evaluated in 2005, 2006 and 2007 using the direct collection method and manual counting. Number of species, diversity and uniformity index were determined. Principal component analysis (PCA) and cluster analysis were used for data interpretation. Results showed that treatment 6 (Astronium fraxinifolium+ Brachiaria decumbens+ sewage sludge) increased the soil macrofauna population by approximately 4 to 6 times more than the other types of cover after three years of evaluation. And the PCA and cluster analysis showed the approximation of the data between treatment 6 and Cerrado, which represents the most appropriate treatment for the recovery of the degraded soil.(AU)

A construção da usina hidrelétrica de Ilha Solteira, no interior de São Paulo, foi iniciada nos anos 1960, quando foi retirado, em média, 8,60 m de solo em profundidade, dando origem a uma área degradada. Com isso, iniciou-se em 2005 um plano de recuperação da área no município de Selvíria/MS com plantio de espécies vegetais adaptadas ao bioma Cerrado. Assim, este trabalho teve como objetivo avaliar a macrofauna do solo de uma área em processo de recuperação com plantio de diferentes tipos de cobertura vegetal (1- solo nu (testemunha); 2- vegetação nativa de Cerrado; 3- espécie arbórea Astronium fraxinifolium; 4- Astronium fraxinifolium + Canavalia ensiformis; 5- Astronium fraxinifolium + Raphanus sativus; 6- Astronium fraxinifolium + Brachiaria decumbens + lodo de esgoto). A macrofauna de solo foi avaliada em 2005, 2006 e 2007 utilizando o método de coleta direta e contagem manual. Foram determinados: quantidade de espécies e índices de diversidade e uniformidade. As análises de componentes principals (PCA) e de cluster foram utilizadas para interpretação de dados. Os resultados mostraram que o tratamento 6 (Astronium fraxinifolium + Brachiaria decumbens + lodo de esgoto) aumentou a população de macrofauna do solo em aproximadamente 4 a 6 vezes mais que os demais tipos de cobertura vegetal após três anos de avaliação. As análises de PCA e de cluster mostraram aproximação dos dados do tratamento 6 às condições ambientais naturais de Cerrado, indicando ser o tratamento mais adequado para a recuperação do solo degradado.(AU)

Nonlinear quantile regression to describe the dry matter accumulation of garlic plants / Regressão quantílica não linear para descrever o acúmulo de matéria seca de alho

The objective of this study was to adjust nonlinear quantile regression models for the study of dry matter accumulation in garlic plants over time, and to compare them to models fitted by the ordinary least squares method. The total dry matter of nine garlic accessions belonging to the Vegetable Germplasm Bank of Universidade Federal de Viçosa (BGH/UFV) was measured in four stages (60, 90, 120 and 150 days after planting), and those values were used for the nonlinear regression models fitting. For each accession, there was an adjustment of one model of quantile regression (τ=0.5) and one based on the least squares method. The nonlinear regression model fitted was the Logistic. The Akaike Information Criterion was used to evaluate the goodness of fit of the models. Accessions were grouped using the UPGMA algorithm, with the estimates of the parameters with biological interpretation as variables. The nonlinear quantile regression is efficient for the adjustment of models for dry matter accumulation in garlic plants over time. The estimated parameters are more uniform and robust in the presence of asymmetry in the distribution of the data, heterogeneous variances, and outliers.(AU)

Este trabalho teve como objetivo ajustar modelos de regressão quantílica não linear para o estudo do acúmulo de matéria seca total em plantas de alho ao longo do tempo, e compará-los com modelos ajustados pelo método dos mínimos quadrados. A matéria seca total de nove acessos de alho pertencentes ao Banco de Germoplasma de Hortaliças da Universidade Federal de Viçosa (BGH/UFV) foi avaliada em quatro períodos (60, 90, 120 e 150 dias após plantio), e estes valores foram utilizados para o ajuste de modelos de regressão - não linear - logística. Para cada acesso, foram ajustados um modelo de regressão quantílica (τ=0,5) e um modelo pela metodologia dos mínimos quadrados. Para avaliar a qualidade de ajuste dos modelos foi utilizado o Critério de Informação de Akaike. Os acessos foram agrupados pelo algoritmo UPGMA, utilizando as estimativas dos parâmetros com interpretação biológica como variáveis. A regressão quantílica não linear foi eficiente no ajuste de modelos para descrição do acúmulo de matéria seca ao longo do tempo. As estimativas de parâmetros foram mais uniformes e robustas na presença de dados assimétricos, variâncias heterogêneas e de valores discrepantes.(AU)