ABSTRACT: The road system is the main mode used for the transportation of agricultural cargo, and in some cases, it is the only option for handling this type of product. This dependence means that the implementation of tools to support the management of logistical costs can reduce the financial impact with the transport felt by the economic agents operating in the soybean chain. This study contributed to a better understanding of the variables that make up the cost of road freight, generating a system of road freight prediction from a multiple linear regression model using the selection of variables Stepwise, Forward, and Backward elimination. This being said, this research intends to evaluate whether the behavior of soybean road freight is influenced by the variables that make up the productive, economic, and infrastructure dimensions in price formation. The regression models had an explanatory power of 87.20%. In the infrastructure dimension, the most impact variable in soybean road freight was the distance traveled; in the economic dimension, the variables of inflation and fuel price stood out; while in the productive dimension, the main contribution was the volume of production. A more assertive predictability of logistical costs and better understanding of the dynamics of freight price formation helps industry agents in planning and decision-making. Another contribution of this study is that it can be used as a practical tool for predicting soybean road freight on several transportation routes.

RESUMO: O sistema rodoviário é o principal modal utilizado para o transporte de cargas agrícolas, e em alguns casos, é a única opção para movimentação desse tipo de produto. Esta dependência faz com que a implementação de ferramentas para apoiar a gestão dos custos logísticos possa reduzir o impacto financeiro com o transporte sentido pelos agentes econômicos que atuam na cadeia da soja. O presente trabalho visa contribuir para um melhor entendimento das variáveis que compõem o custo dos fretes rodoviários, gerando um sistema de previsão de fretes rodoviários a partir de um modelo de regressão linear múltipla usando a seleção de variáveis Stepwise, Forward e a eliminação Backward. Isto posto, a pesquisa tem por objetivo avaliar se o comportamento do frete rodoviário da soja é influenciado pelas variáveis que compõem as dimensões produtivas, econômicas e de infraestrutura na formação do preço. Os modelos de regressão tiveram um poder explicativo de 87,20%. Na dimensão infraestrutura o destaque foi a variável distância percorrida como a mais impactante no frete rodoviário da soja, na dimensão econômica as variáveis inflação e preço do combustível, enquanto que na dimensão produtiva a principal contribuição foi o volume de produção. A previsibilidade mais assertiva dos custos logísticos e melhor compreensão da dinâmica de formação do preço do frete auxilia os agentes do setor no planejamento e na tomada de decisão. Outra contribuição deste trabalho é que pode ser usado como uma ferramenta prática para a predição de fretes rodoviários da soja em diversas rotas de transporte.

ABSTRACT Crop pests have negative impacts on yield. This paper proposes a spatiotemporal geostatistical modeling to compare data of adult Syrphidae fly count and corn leaf aphid Rhopalosiphum maidis (Fitch, 1856) colonies in corn crops. The use of a geostatistical model that allows the space-time variation makes the approach more interesting because it is a more complete model. Multiple regression was used to model the trend component for the variable response adult Syrphidae fly count and corn leaf aphid colonies, with the coordinates serving as covariates and the spatiotemporal variations around the deviation are described by a random spacetime residual field. Finally, the prediction map obtained by kriging may be a biological indicator of possible corn leaf aphid colonies in the corn crop. It was possible to verify that the occurrence of the pest provided a significant increase in adult predators and seminatural habitats may favor populations of natural enemies.

ABSTRACT: The adaptation of the Global Navigation Satellite Systems (GNSS) technology to fit the needs of farmers requires knowledge of the accuracy level delivered by a GNSS receiver in working conditions. To date, no methodology indicates the minimum number of replications to perform a statistical comparison. This study aims to advance knowledge on the methodological approach for evaluating the static and dynamic performance of GNSS receivers commonly used in agricultural operations. For the static test, a supporting frame in the ground carried all the receivers with coordinates properly transported. In the dynamic test, a circular rail with a 9.55 m radius was installed at ground level with a platform driven by an electric motor to carry the receivers at a constant speed. The transversal error of the receiver to the circular reference line was measured. The error with 95 % probability (E95) to receivers without differential correction ranged between 4.22 m and 0.85 m in the static test, and 2.25 m and 0.98 m in the dynamic test. Receivers with differential correction had E95 values below 0.10 m in the static test and 0.16 m in the dynamic test. Receivers with C/A code require five replications at minimum and 13 replications are needed for L1/L2 with differential correction signals in the dynamic test. The static test needs nine replications for C/A and five for L1/L2 with differential correction signals.

RESUMO Objetivou-se avaliar, por meio de análise multivariada de dados, quais resíduos de leguminosas arbóreas tem melhor potencial fertilizante para culturas agrícolas no semiárido nordestino brasileiro. O experimento foi conduzido em vasos, em delineamento aleatorizado em blocos, com sete tratamentos e quatro repetições. Para constituir os tratamentos utilizaram-se resíduos de sabiá, jurema-preta e gliricídia; além de duas partes da planta: folhas e folhas mais galhos. Os vasos foram preenchidos com 8,0 dm3 de solo e os resíduos foram adicionados na forma de massa verde, correspondendo a 73,0 g de massa seca por vaso. Sementes de milho foram semeadas e aos 65 dias após adição dos resíduos avaliou-se atributos químicos do solo, crescimento e teores de nutrientes das plantas. Os dados foram estudados por meio das análises de componentes principais, agrupamento, função discriminante canônica e teste de comparação de médias a partir da varável canônica 1. Resíduos de gliricídia influenciaram positivamente K e Mg do solo, bem como altura, diâmetro do caule, número de folhas e teores foliares de P, N e Mg em plantas de milho. Estes resíduos apresentaram maior dissimilaridade e separação em relação ao tratamento controle e proporcionaram médias estatisticamente superiores aos demais tratamentos. Folhas de jurema-preta influenciaram positivamente Ca, N e COT do solo, bem como teores foliares de K e Ca e matéria seca total do milho. A análise estatística multivariada permitiu identificar potenciais distintos entre resíduos de leguminosas para uso como fertilizante na cultura do milho, sendo a espécie gliricídia a que apresenta maior potencial.

ABSTRACT The objective of this study was to evaluate, through multivariate data analysis, which tree legume residues have the best fertilizer potential for agricultural crops in the semi-arid region of northeastern Brazil. The experiment was conducted in pots, in a randomized block design, with seven treatments and four replicates. Treatments consisted of residues of Sabiá, Jurema Preta and Gliricidia, besides two parts of the plant: leaves and leaves + branches. The pots were filled with 8.0 dm3 of soil and the residues were added in the form of green mass, corresponding to 73.0 g of dry mass per pot. Maize seeds were sown and, at 65 days after addition of the residues, soil chemical attributes, growth and nutrient contents in the plants were evaluated. The data were studied through principal component analysis, clustering analysis, canonical discriminant function analysis and means comparison test from canonical variable 1. Gliricidia residues positively influenced soil K and Mg contents, as well as height, stem diameter, number of leaves and leaf contents of P, N and Mg in maize plants. These residues showed greater dissimilarity and separation compared to the control treatment and led to statistically higher means compared to the other treatments. Jurema Preta leaves positively influenced soil Ca, N and TOC, as well as leaf contents of K and Ca and total dry mass of maize. Multivariate statistical analysis made it possible to identify distinct potentials among legume residues for use as fertilizer in maize crop, and Gliricidia is the species with highest potential.

RESUMO Durante o controle químico de insetos, doenças e plantas daninhas, dá-se muita importância ao produto fitossanitário e pouca atenção à técnica de aplicação. O controle de pragas da soja não escapa à regra geral e, dessa forma, algumas pragas ditas como secundárias, e até mesmo inexistentes, passaram a ser responsáveis por grandes prejuízos. O objetivo desse trabalho foi avaliar a aplicação de inseticida em diferentes velocidades (5 e 16 km h-1) variando as taxas da aplicação entre 108 a 110 e 199 a 216 L ha-1 para quantificar a diferença na porcentagem de cobertura do inseticida aplicado no dossel de plantas de soja e verificar a influência desses fatores em parâmetros de eficácia para o controle das lagartas (Helicoverpa armigera e Chrysodeixis includens). De modo geral, a maior cobertura foliar pelo inseticida foi observada no terço superior do dossel, independente da taxa e velocidade de aplicação, refletindo em menores injúrias foliares. Para os terços médio e inferior, a diminuição da velocidade teve mais influência na diminuição do dano foliar do que o aumento do volume.

ABSTRACT During the chemical control of pests, diseases and weeds, great importance is given to the phytosanitary product and little attention to the application technology. The control of soybean pests did not escape the general rule and, therefore, some pests known as secondary, and even nonexistent, became responsible for great damage to the soybean crop. The objective of this work was to test the application of insecticide at different speeds (5 and 16 km h-1) by varying the rates of application in 108 to 110 and 199 to 216 L ha-1 to quantify the difference in the coverage percentage of the applied insecticide in the canopy of soybean plants, and to verify the interaction of these factors with efficacy parameters for the control of caterpillars (Helicoverpa armigera and Chrysodeixis includens). In general, the highest leaf coverage by the insecticide was observed in the upper part of the canopy, regardless of the rate and speed of application, resulting in lower leaf damage. For the middle and lower thirds of the plant, the decrease in speed influenced more the decrease in leaf damage by the caterpillars than the increase in the spray volume.

Abstract Objective To clinically assess the effect of desensitizing gels and dentifrices on the reduction in pain sensitivity and color variation during tooth bleaching. Methodology A total of 108 volunteers were randomly separated into the following groups of n=12: GT/S-glycerine and thickener/sucralose; NF/S-potassium nitrate and sodium fluoride/sucralose; NA/S-potassium nitrate and arginine/sucralose; GT/AC-glycerine and thickener/arginine and calcium carbonate; NF/AC-potassium nitrate and sodium fluoride/arginine and calcium carbonate; NA/AC-potassium nitrate and arginine/arginine and calcium carbonate; GT/PN-glycerine and thickener/potassium nitrate; NF/PN-potassium nitrate and sodium fluoride/potassium nitrate; and NA/PN-potassium nitrate and arginine/potassium nitrate. Sensitivity was assessed with the numerical analogue scale, and color variation (ΔE) was measured with a spectrophotometer. The sensitivity values obtained were subjected to a multivariate analysis of variance (MANOVA) and color variation values were subjected to a randomized analysis of variance (p<0.05). Results The NF/AC, NA/AC, NF/PN, and NA/PN groups presented lower sensitivity values and reduced sensitivity compared to those of the other groups throughout the clinical sessions. None of the groups showed sensitivity at the 24-week assessment. Statistically, no significant difference were observed in the color values among the groups four weeks after the beginning of bleaching (p=0.074). Additionally, the color assessment of all groups was statistically similar four weeks (p=0.084) and 24 weeks (p=0.118) after the beginning. Conclusion Our results indicate that adding NF/S, NA/S, NF/AC, and NA/AC desensitizers to tooth bleaching protocols reduces pain sensitivity without affecting its effectiveness.

RESUMO A demanda por cafés com alta qualidade pelos consumidores tem gerado um grande interesse dos produtores em atender esse mercado. Análises fisiológicas que podem ser associadas com a análise sensorial do café podem garantir resultados mais confiáveis para a avaliação da qualidade do café. Objetivou-se com o estudo investigar o potencial de utilização das análises fisiológicas na determinação da qualidade do café, por meio da aplicação de análises multivariadas. Lotes de grãos de café foram colocados sob armazenamento em câmara a 10 ºC, e então foram realizadas avaliações da qualidade sensorial e fisiológica e das características químicas dos grãos antes do armazenamento e após três e seis meses de armazenamento. As variáveis de qualidade fisiológica dos grãos de café foram correlacionadas com a análise sensorial da bebida. A viabilidade dos embriões de café analisada pelo teste de tetrazólio foi positivamente correlacionada com a nota final da análise sensorial. Há correlação da matéria seca das raízes, matéria seca do hipocótilo, lixiviação de potássio e condutividade elétrica com os atributos sensoriais que compõem a nota final da análise sensorial dos grãos de café. 97,14% da variação da nota final da análise sensorial foi explicada pelas variáveis de emergência radicular (r2 = 2.27%), plântulas normais fortes (r2 = 0.56%), plântulas com folhas cotiledonares expandidas (r2 = 0.53%), teste de tetrazólio (r2 = 91.54%) e lixiviação de potássio (r2 = 2.24%). Mais estudos são necessários para permitir o uso das análises fisiológicas para complementar a análise sensorial da bebida.

ABSTRACT The demand for high-quality coffee among consumers has generated a great deal of interest among producers in serving this market. Parameters for physiological analyses that can be associated with aspects of sensory analyses of coffee can ensure more reliable results for coffee quality assessments. The aim of this study was to investigate the potential of physiological analyses in determining coffee quality through multivariate analysis. Several samples from coffee bean/seed lots were placed in cold storage at 10 °C, after which the sensory quality, physiological quality, and chemical characteristics of the beans were evaluated before storage and after three and six months of storage. The variables of physiological quality in the coffee beans were correlated with sensory analysis parameters. The viability of coffee embryos revealed by the tetrazolium test results were positively correlated with the final sensory analysis score. There was a correlation of root dry matter, hypocotyl dry matter, potassium leaching, and electrical conductivity with the sensory attributes that comprise the final sensory analysis score for the coffee beans. Variation in the final sensory analysis score was explained up to 97.14% by the variables radical emergence (r2 = 2.27%), strong normal seedlings, (r2 = 0.56%), seedlings with expanded cotyledonary leaves (r2 = 0.53%), tetrazolium test results (r2 = 91.54%), and potassium leaching (r2 = 2.24%). More studies are required to enable the use of physiological analyses to complement sensory analysis.

Resumo: O objetivo deste trabalho foi avaliar o desempenho em campo de nectarineiras 'Sunraycer' autoenraizadas e sobre 13 porta-enxertos clonais. Para tanto, foram avaliados florescimento, brotação, maturidade dos frutos, vigor e produção. O intervalo entre o final do florescimento e a época da colheita foi menor para 'Sunraycer' sobre os porta-enxertos 'G x N.9', 'Santa Rosa' e 'Ishtara'. 'Flordaguard' e 'Ishtara' induziram o maior e o menor volume de copa, respectivamente. 'Flordaguard' resultou na maior produção, e 'Cadaman', na menor. Plantas 'Sunraycer' autoenraizadas produzem frutos de maior massa e podem ser uma alternativa para os produtores.

Abstract: The objective of this work was to evaluate the performance in the field of 'Sunraycer' nectarine plants when own rooted and budded onto 13 clonal rootstocks. For this, flowering, flushing, fruit maturity, vigor, and production were assessed. The time span between the end of flowering and the harvest period was shorter for 'Sunraycer' budded onto the 'G x N.9', 'Santa Rosa', and 'Ishtara' rootstocks. 'Flordaguard' and 'Ishtara' induced the largest and smallest canopy sizes, respectively. 'Flordaguard' resulted in the greatest production, and 'Cadaman', in the lowest. Own-rooted 'Sunraycer' plants produce heavier fruits and can be an alternative to growers.

ABSTRACT: The use of mineral phosphate fertilizers associated with organic residues can improve fertilizer use efficiency and consequently decrease their usage costs. Soil application of filter cake (FC) can provide nutrients and enhance physical quality. This study aimed to evaluate the effects of different phosphate fertilizers [rock phosphate (RP) and triple superphosphate (TSP)] applied at different rates (90 and 180 kg ha-1 P2O5) associated with filter cake (10 Mg ha-1 dry matter) on the soil phosphorus (P) fractions after two consecutive seasons of sugarcane in two distinct soils, sandy and clayey. Yield was significantly improved with FC addition in the first year in both soils, while inorganic P sources did not influence crop yield at either location and in both years. Organic and residual P forms were only slightly altered in the sandy soil. The most significant changes occurred in the labile and moderately labile P fractions in both soils. Filter cake was an effective source of nutrients for plant development, increasing the levels of soil available P and keeping it at agronomically adequate levels for up to two years, however it was not able to facilitate the P release from mineral fertilizers, irrespective of the source or rate.

RESUMO O escurecimento lento de grãos é almejado por melhoristas de feijoeiro porque o consumidor considera que grãos mais escuros apresentarão maior tempo para cocção. A análise empregada atualmente leva ao redor de 90 dias para diferenciação da cor do grão entre os genótipos. Objetivou-se avaliar a cor em função do valor de L* (luminosidade) de feijoeiro do tipo carioca pelos métodos natural e acelerado para verificar equivalência entre os métodos, validação da metodologia e identificação de genótipos tolerantes ao escurecimento. O escurecimento de grãos foi comparado e avaliado pelo método de escurecimento natural em condições de prateleira, em dias de armazenamento, e pelo método de escurecimento acelerado, em condições de luz ultravioleta, em horas. O escurecimento natural de 90 dias foi estatisticamente igual a 24 horas de escurecimento acelerado, e a diferença entre os genótipos pôde ser obtida em menor tempo, indicando correspondência entre os métodos. O método de escurecimento acelerado pode ser utilizado para encurtar o tempo de análise na rotina dos programas de melhoramento.

ABSTRACT The slow darkening of grains is sought by bean breeders because the consumers consider that darker grains demand more time for cooking. The analysis currently used takes around 90 days to differentiate grain color among genotypes. The objective was to evaluate the color as a function of the value of L* (lightness) of carioca beans, by natural and accelerated methods to verify equivalence between methods, validation of the methodology and identification of genotypes tolerant to the darkening. The grain darkening was compared and evaluated by natural darkening method under shelf conditions, in days storage, and accelerated darkening method under ultraviolet light, in hours. The natural darkening time of 90 days was statistically equal to 24 hours of accelerated darkening, and the difference among the genotypes could be obtained in a shorter time, indicating a correspondence in the methods. The accelerated darkening method can be used to shorten the analysis time in the routine of breeding programs.

Resumo: O objetivo deste trabalho foi propor um esquema de ponderação para o modelo de efeitos principais aditivos e interação multiplicativa (AMMI), bem como avaliar a utilidade deste modelo W-AMMI no estudo da interação genótipo x ambiente (GxA) e da interação de locos associados a caracteres quantitativos x ambiente (QxA) para dados não replicados. Utilizou-se a população de cevada (Hordeum vulgare) 'Harrington' x TR306, com 141 genótipos avaliados em 25 ambientes, para comparar os resultados do modelo AMMI com os de duas versões propostas do modelo W-AMMI: pesos iguais por linha e pesos iguais por coluna. O algoritmo W-AMMI de colunas proposto é viável para analisar informação com heterogeneidade de variâncias, quando não há repetições disponíveis. O uso dos modelos AMMI e W-AMMI, nos casos indicados, melhora a detecção de QTLs, além de propiciar uma intepretação adequada da GxA e um melhor entendimento da QxA, o que possibilita a obtenção de informações importantes para o aumento da produtividade em diferentes ambientes.

Abstract: The objective of this work was to propose a weighting scheme for the additive main effects and multiplicative interactions (AMMI) model, as well as to assess the usefulness of this W-AMMI model in the study of genotype x environment interaction (GxE) and quantitative trait locus x environment interaction (QxE) for nonreplicated data. Data from the 'Harrington' x TR306 barley (Hordeum vulgare) mapping population, with 141 genotypes evaluated in 25 environments, were used to compare the results from the AMMI model with those of two proposed versions of the W-AMMI model: equal weights per row and equal weights per column. The proposed W-AMMI columns algorithm is viable to analyze data with heterogeneous variance, when there are no replicates available. The use of the AMMI and W-AMMI models, in the indicated cases, improves QTL detection, besides providing a sound interpretation of GxE and a better understanding of QxE, which allows obtaining valuable information on increasing productivities in different environments.

ABSTRACT The objective of this study was to evaluate productive traits in sheep fed roughage-free diets by multivariate analysis. Forty lambs were used in this study: 20 Santa Inês animals, consisting of 10 uncastrated males and 10 females; and 20 crossbreds (½ Santa Inês × Dorper), consisting of 10 uncastrated males and 10 females, at an average age of five months. Lambs were randomly allocated into the following treatments: Santa Inês males fed once daily (SM1); Santa Inês males fed twice daily (SM2); Santa Inês females fed once daily (SF1); Santa Inês females fed twice daily (SF2); crossbred males fed once daily (CM1); crossbred males fed twice daily (CM2); crossbred females fed once daily (CF1); and crossbred females fed twice daily (CF2). In the multivariate analysis, a difference was detected between the mean values for production classes and feeding-behavior variables (Wilks, Pillai, Hotelling-Lawley, and Roy tests). Tocher's optimization method had two groups formed: Group I, comprising treatments SM1, SM2, SF1, SF2, CF1, and CF2; and Group II, containing treatments CM1 and CM2 (crossbred males). When production and cud chews per day were evaluated, neutral detergent fiber digestibility and final weight were the performance-digestibility variables that most contributed to explaining the variation between treatments. When the feeding behavior was assessed, the time spent on other activities was the variable that most contributed. The crossbred genotype (½ Santa Inês × Dorper) and the male sex have superior performance for weight-related traits. However, when these animals are confined with females, it is recommended to supply the feed only once daily, irrespective of the genetic group.

ABSTRACT: The system of differential equations proposed by Oltjen et al. [1986, named Davis Growth Model (DGM)] to represent cattle growth has been parameterized with data from Bos taurus (British) and Bos indicus (Nellore) breeds. The DGM has been successfully used for simulation and decision support in the United States. However, the effect of about 30 years of genetic improvement and the use of different breeds may affect the model parameter values, which also may need to be re-estimated for crossbred animals. The aim of this study was to estimate parameter values and confidence intervals for the DGM with growth and body composition data from Zebu crossbred animals. Confidence intervals and asymptotic distribution were generated through nonparametric bootstrap with data from a field experiment conducted in Brazil. The parameters showed normal probability distribution for most scenarios. The rate constant for deoxyribonucleic acid (DNA) synthesis had a minimum increase of 156 % and the maximum of 389 %, compared to the original values and the maintenance requirement had a minimum increase of 126 % and maximum of 160 % compared to the original values. Lower limits of 95 % confidence intervals for the parameters related to maintenance and protein accretion rates were higher than the original estimates of the DGM, evidencing genetic differences of the Zebu crossbred animals in relation to the original DGM parameters.

RESUMO Morangos são apreciados em todo o mundo. No entanto, uma grande quantidade de produtos agroquímicos é utilizada na sua produção por serem muito susceptíveis a pragas e doenças. Muitos estudos têm comparado à qualidade de frutos provenientes do sistema orgânico e do sistema convencional, mas os resultados são contraditórios. O objetivo deste estudo foi comparar a qualidade de morangos (Fragaria ananassa Duch) cultivados sob métodos de cultivo orgânico e convencional. Setepares de fazendas foram selecionados, e frutos foram coletados em diferentes momentos e locais de produção. O delineamento experimental foi inteiramente casualizado, com esquema fatorial 2 x 5 (dois tipos de cultivo x cinco períodos de armazenamento), com quatro repetições. Morangos produzidos no sistema de cultivo orgânico apresentaram maiores teores de sólidos solúveis e polpa mais firme que os produzidos no sistema convencional. A perda de massa fresca, acidez titulável e os teores de ácido ascórbico não foram influenciados pelos sistemas de cultivo. O sistema convencional resultou em frutos com menores índices de podridão, enquanto que morangos provenientes do sistema de cultivo convencional exibiram frutos com conteúdo maior de sólidos solúveis e polpa firme. Desta forma, neste trabalho foi observado que cada sistema de cultivo foi responsável em beneficiar diferentes atributos de qualidade em morangos.

ABSTRACT Strawberries are appreciated worldwide. However, a large quantity of agrochemicals is used in their production because of their highly susceptibility to pests and diseases. Many studies have compared the quality of fruits grown on organic production system and conventional system, but results are often contradictory. The aim of this study was to compare the strawberries fruits quality (Fragaria ananassa Duch) grown under organic and conventional production systems. Seven pairs of farms were selected, and fruits were collected at different times and production locations. Experimental design was completely randomized, with a 2 x 5 factorial scheme (two production system types x five storage periods) with four replicates of ten strawberries. Strawberries produced under organic production system exhibited higher soluble solids contents and firmer pulp than those produced under conventional system. Weight loss, titratable acidity and ascorbic acid concentrations were not influenced by farming systems. Conventional system resulted in fruits with lower rot index, while strawberries produced under organic production system exhibited higher soluble solids contents and firmer pulp. Thus, in this study it was observed that each production system was responsible for benefit different attributes in strawberries.

Resumo: O objetivo deste trabalho foi caracterizar as variáveis fisiológicas e produtivas da videira 'Niágara Rosada' (Vitis labrusca) nos sistemas de condução em espaldeira e em Y, nos dois primeiros anos de produção. Nos ciclos produtivos de 2014 e 2015, avaliaram-se os seguintes parâmetros: índice de área foliar, fotossíntese, transpiração, condutância estomática, área de superfície foliar, variáveis de produção e qualidade do fruto. No primeiro ano de produção, houve diferenças entre os sistemas de condução quanto às variáveis ecofisiológicas influenciadas pela área de superfície foliar dos dosséis. No segundo ano de produção, não houve diferenças entre as variáveis ecofisiológicas. O número de cachos por área de superfície foliar, a massa do cacho, o número de bagas por cacho e a produção por planta não apresentaram diferenças entre os sistemas de condução. Videiras do primeiro e do segundo ano de produção não apresentaram diferenças entre os sistemas de condução, quanto às relações entre área de superfície foliar e produção; porém, a produtividade foi superior no sistema em espaldeira, em função do maior número de plantas por hectare. Frutos produzidos no sistema em Y apresentaram maior quantidade de pigmentos, como antocianinas e flavonóis, do que aqueles no sistema em espaldeira, com a mesma a quantidade de sólidos solúveis totais.

Abstract: The objective of this work was to characterize the physiological and productive variables of 'Niagara Rosada' vine (Vitis labrusca) trained in vertical shoot positioning (VSP) and in Y-shaped systems, in the first two years of production. In the 2014 and 2015 growing seasons, the following parameters were evaluated: leaf area index, photosynthesis, transpiration, stomatal conductance, leaf surface area, production variables, and fruit quality. In the first year of production, there were differences between the training systems for the ecophysiological variables affected by the leaf surface area of the canopies. In the second year of production, there were no differences between the ecophysiological variables. The number of clusters per leaf surface area, cluster mass, number of berries per cluster, and production per plant showed no differences between the training systems. Vines in the first and second years of production showed no differences between the two training systems for the relationships between leaf surface area and production; however, yield was higher in the VSP system because of the greater number of plants per hectare. Fruit produced in the Y-shaped system showed a greater amount of pigments, such as anthocyanins and flavonols, than those in the VSP system, with the same amount of total soluble solids.