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RESUMO A irrigação deficitária é comumente utilizada em regiões de reduzida disponibilidade de água ou de energia para a irrigação e visa incrementar a eficiência de uso da água. Essa técnica pode ser adequada à cultura do sorgo, que apresenta produtividades satisfatórias, mesmo em condições limitadas de disponibilidade de água no solo. Os objetivos do trabalho foram: avaliar os efeitos de diferentes manejos de irrigação deficitária sobre o índice de área foliar, altura de plantas e rendimento de grãos do sorgo, e identificar o nível crítico de irrigação deficitária que proporciona maior produtividade da água irrigada e retorno econômico. O experimento foi desenvolvido no ano agrícola de 2012/2013, sob uma cobertura móvel, que impedia a ocorrência de chuva na área experimental. Foram testados quatro manejos de irrigação deficitária: 100; 75; 50 e 25% de reposição da evapotranspiração da cultura (ETc). A redução de 25% na reposição da ETc resultou na diminuição de 7% na altura das plantas, 5% no índice de área foliar e 17% no rendimento de grãos. A maior receita líquida da cultura foi alcançada utilizando o manejo de irrigação com reposição de 75% da ETc. A produtividade da água e o retorno econômico da aplicação de água apresentaram uma resposta linear positiva em relação à redução na reposição da ETc.

Soil physical quality can be easily and quickly evaluated by using simple equipment to identify levels of soil compaction. Hence, it is necessary to know the variables responsible for changes in the soil penetration resistance (SPR). The aim of this review is to identify the main factors related to the various equipment used for assessing SPR as a soil physical quality indicator in agriculture. This literature review describes the different types of equipment used and its relationship with SPR. A wide range of procedures, devices, and equipments are available. Much of variability in SPR results is related to the equipment model, cone angle and diameter, and penetration rate. Usually, restrictions to root growth are correlated with SPR values above 2-3 MPa. However, comparisons of SPR values obtained under different soil moisture regimes in the same soil type have provided conflicting results of difficult interpretation. In order to minimize these problems, there is a need for standardization of measurement procedures and interpretation, and/or correction of SPR values according to a soil water content of reference.

O sucesso na utilização de modelos matemáticos no estudo do transporte de íons no solo está intimamente ligado à precisão com que os parâmetros de transporte envolvidos neste processo são estabelecidos. De maneira geral, tais parâmetros são determinados mediante a resolução de um problema de otimização não linear em que os dados experimentais, obtidos em ensaios de deslocamento miscível, são ajustados a um modelo teórico. Neste sentido, a utilização de softwares de alta performance no ajuste destes parâmetros mostra-se vantajosa, uma vez que, além da consistência e da disponibilidade de ferramentas numéricas preexistentes, possibilita a incorporação de novas rotinas de acordo com o fenômeno que se queira simular. Sendo assim, este trabalho teve como objetivo desenvolver, em ambiente MATLAB 6.5, uma rotina computacional para a otimização dos seguintes parâmetros de transporte: fator de retardamento (R) e coeficiente de dispersão (D). A rotina desenvolvida foi aplicada a dados experimentais de três ensaios de deslocamento miscível do íon potássio em colunas preenchidas com um Latossolo Vermelho- -Amarelo, fase arenosa. A qualidade dos ajustes obtidos foi avaliada utilizando-se do coeficiente de exatidão. Concluiu-se que a rotina proposta apresentou ótimo desempenho, o que, além de reforçar a consistência do método numérico utilizado, indica que a rotina proposta neste trabalho pode contribuir com o avanço dos estudos teóricos da dinâmica da água e de solutos em meios porosos não saturados.The successful use of mathematical models in studies of solute transport in soil is dependent on the accuracy to which the transport parameters involved in this process can be specified. In general, these parameters are determined by using nonlinear optimization techniques to fit theoretical models to experimental data obtained in miscible displacement experiments. The use, therefore, of high-performance software to evaluate these parameters appears to be advantageous since, in addition to consistency and the availability of pre-existing numerical routines, such software allows for the incorporation of new routines that are specifically tailored for the phenomena being simulated. The main objective of this study was to develop a MATLAB 6.5 computational routine to optimize the evaluation of retardation factor (R) and dispersion coefficient (D) from miscible displacement data. This routine was applied to experimental data from three miscible displacement studies of potassium transport in columns filled with an Oxisol of sandy phase, with the setting quality being assessed by the coefficient of accuracy. The proposal routine gave excellent results, reinforcing the consistency of the numerical method used, and indicating that this routine can contribute to the advancement of theoretical studies of the solute-water dynamics in unsaturated porous media.

ABSTRACT This study was conducted to assess prediction models for production indexes in batches of growing pigs using performance regressors (period of the year and farm size). A database containing 663 records on the performance of pig batches (18.83 ± 4.37 to 111.26 ± 10.59 kg body weight (BW) at housing and finisher, respectively) from a private company was used to assess the following average animal characteristics: initial number of animals (INA), initial BW (IBW), initial age (IA), final BW (FBW), final age (FA), daily feed intake (DFI) and feed conversion ratio (FCR). Data were categorized by period (P) of the year (P1 = Nov to Apr and P2 = May to Oct), and farm size (FS): 0 ≤ INA ≤ 1,000, FS1; 1,001 ≤ INA ≤ 2,000, FS2; 2,001 ≤ INA ≤ 3,000, FS3; and INA > 3,000, FS4. The analysis resulted in representing 58 % of the variance of FCR data. The INA impaired FCR, and having larger pig batches improves FCR and profitability. The FBW prediction errors ranged from 2.47 to 3.38 %. Feed conversion ratio prediction errors ranged from 3.27 to 4.47 %. Based on the joint criteria of non-bias and accuracy, the models for predicting the FBW of growing pig batches have practical value in animal science on account of their accuracy. In addition, increasing the initial number of housed pigs in batches affects the FCR regardless of the period of the year.

ABSTRACT Nitrogen (N) fertilization effectiveness in onion depends on N source, as well as on soil type and management system. The aim of the study is to investigate the effect of N sources and doses applied as top-dressing on bulb yield, leaf N contents and on the postharvest conservation of onion bulbs grown under no-tillage (NTS) and conventional tillage (CTS) systems. Three experiments were carried out: two in Lebon Régis County-SC, under NTS; and one in Caçador County-SC, under CTS. The herein tested N sources comprised urea, ammonium nitrate, calcium nitrate and ammonium sulfate, in combination to N doses applied as top-dressing (70, 140, 210, 280 and 350 kg N ha-1) in addition to the control, without N. The N sources did not affect yield parameters, leaf N content and post-harvest onion losses. The maximum technical efficiency in bulb yield was observed at N doses of 195.8 and 258.4 kg ha-1 in the no-tillage system (NTS) and at 270.7 kg N ha-1 in the CTS. The NTS enabled maximum yield at N dose 47% lower than the officially recommended one. Maximum relative commercial yield was associated with 31.1 g kg-1 of leaf N.

The research quiestion is how do some biotic and abiotic variables, under a silvopastoral system exert influence on the animal movement? These studies have been carried out through different approaches and have included analyses from empirical to statistical. The aim of this study was to relate cattle grazing sites with some biotic and abiotic factors under a silvopastoral system. The fieldwork was carried out in a paddock of the farm La Reforma located in the upper part of the Magdalena River basin (Tolima, Colombia). Through global positioning devices (GPS), movement, grazing route, and resting data that cattle perform in these habitats during daytime hours were obtained. Six cows (460 kg live weight, not pregnant) were monitored during two periods of the year at one-minute time intervals. Data were processed in a geographic information systems (GIS) environment, and mechanisms and algorithms were used to establish an association of moving animals with some biotic (pasture productivity and cover, trees, and floristic composition) and abiotic factors (climatological season, access to drinking and salt troughs). The results suggest an association between animal movement concerning the different attractants for which the drinking and salt troughs in the paddocks were relevant. In conclusion, the analysis of animal behavior at the landscape level is useful for decision-making in the design of livestock landscapes.

Abstract The objective of this work was to evaluate the bromatological composition, bioactive compounds, antioxidant activities, and color of the leaves of olive cultivars Arbosana, Arbequina, Frantoio, Manzanilla, and Koroneiki in northwestern Paraná, Brazil. Leaves of each cultivar were collected for the experiment, which was carried out in a completely randomized design. The dry matter (DM) of olive leaves contains mostly carbohydrates (56.15 to 59.42 g 100 g-1 DM) and fibers (17.37 to 19.73 g 100 g-1 DM) in its bromatological composition. The total polyphenol content ranges from 13.27 to 22.81 mg GAE g-1, with cultivar Manzanilla standing out, and the flavonoid content from 6.50 to 7.65 mg QE g-1. Manzanilla shows the highest antioxidant activity of 93.56 and 78.15% in the DPPH and ABTS assays, respectively. When compared with the other cultivars, Manzanilla and Koroneiki have leaves with a higher green intensity and total chlorophyll content of 0.958 and 0.833 mg 100 mL 1, respectively. In the ABTS assay, there is a correlation both between total polyphenol content and antioxidant activity and between chlorophyll content and antioxidant activity. Olive leaves have characteristics that allow their application as an additive or ingredient for the development of food products with satisfactory antioxidant activity.

ABSTRACT: The aim of the study was to evaluate the effects of integrated crop-livestock-forestry (ICLF) systems and the thinning of eucalyptus trees on the agronomical performance of soybean. Treatments consisted of cultivation under: crops under full sunlight (CFS) conditions; ICLF with triple-row tree configuration (ICLFT) in which trees were submitted to selective thinning in the fifth year after planting through removal of 50% of trees while maintaining triple-row bands; and ICLF with single-row tree band configuration (ICLFS) in which the lateral rows of the triple-row tree bands were subjected to systematic thinning at the fourth year after planting. The physiological and agronomical variables of the soybean crop were evaluated at the R5 and R8 reproductive stages during the eighth harvesting season (2018/2019). Soybean sampling was carried out at five random positions in the CFS and in four transects at distances of 3, 6, 10 and 15 m from the tree bands in both the north and south faces of the ICLF systems. There were no differences between soybean grown under the ICLF and CFS systems with respect to specific leaf area, plant density, lodging index and mass of a thousand grains. However, the ICLF increased dry leaf mass and leaf area index and reduced soybean plant heights. Soybean productivity was reduced by 26% in ICLF-T and 14% in ICLF-S, that is, a 12% reduction in the productivity loss with systematic thinning. It is concluded that ICLF reduces soybean productivity in the effective grain production area of the system, regardless of the degree of thinning, although systematic thinning by removing the lateral tree lines to conversion of triple-rows into single-rows minimizes the loss of soybean grain yield.

ABSTRACT: This study evaluated the feasibility of abdominal liftfor laparoscopic adrenalectomy and compared it with the conventional laparoscopic technique using pneumoperitoneum with medicinal CO2 in dog cadavers. The total surgical time (TST), adrenalectomy time (AT), and gland integrity after removal were evaluated. Thirty-eight adrenalectomies were performed in 19 cadavers. Regardless of the antimere, the TST was significantly lower in the CO2 procedures than in the lift laparoscopy procedures (P=0.001). When comparing the techniques between antimeres, the TST was significantly higher on the left side with lift laparoscopy than with CO2 (P=0.015) and similar between the techniques on the right side of the animals (P=0.086). In the comparison of AT, regardless of the execution side, no differences were observed between the techniques (P=0.05). The same was observed when AT was evaluated separately using antimeres (P=0.902). Of the 38 adrenals evaluated, 92.1% were removed in a single block, and 32.29% had a superficial lesion in the capsule. There was no difference between the groups in the removal capacity in a single block (P=0.340) and capsule integrity (P=0.287). Abdominal lift for laparoscopic adrenalectomy is a feasible technique in dog cadavers; however, it requires a longer surgical time than the conventional technique. The traction force used to elevate the abdominal wall must be evaluated.

O objetivo deste estudo foi avaliar e validar o uso do sensor Irrigas® de solo no manejo autônomo da irrigação do tomateiro, na região de Caçador, SC. Na safra 2016/17 foi conduzido um experimento em ambiente protegido avaliando cinco tensões de umidade do solo (20, 30, 40, 50 e 60 kPa) para o início da irrigação. Na safra 2017/18 foi conduzido um experimento a campo avaliando três manejos da irrigação (manejo autônomo da irrigação baseado nos sensores Irrigás®; manejo da irrigação baseado na tensiometria convencional; e manejo da irrigação sem critério técnico). Na safra 2018/19 foram avaliados os mesmos manejos da irrigação da safra anterior, com exceção do manejo da irrigação sem critério técnico. Por fim, na safra 2019/2020 foi conduzida uma unidade de validação em ambiente protegido avaliando o manejo autônomo da irrigação do tomateiro baseado no sensor Irrigás®. Na safra 2016/17 a maior produção de frutos comercializáveis (10,9 kg planta-1) foi obtida na tensão de umidade do solo estimada de 44 kPa. Na safra 2017/18 não houve diferenças entre os manejos de irrigação avaliados. Já na safra 2018/19 o manejo da irrigação baseado no sensor Irrigás® obteve produtividade de frutos comercializáveis 18% superior ao manejo baseado na tensiometria convencional. Os sensores Irrigás® permitiram o manejo autônomo da irrigação do tomateiro cultivado em ambiente protegido durante todo o ciclo.

Due to the multifactorial interplay of the morphogenic, morphologic and agronomic characteristics of forage species, it is necessary to find management options that increase the production and utilization of the forage mass of grasses when submitted to different defoliation frequencies and nitrogen application levels The objective of this study was to assess the effects of two defoliation frequencies and two nitrogen levels applied in a single dose on the morphogenic and structural characteristics and forage production of Piatã grass (Brachiaria brizantha cv. Piatã) grown in the rainy season. The experiment was carried out in the agrostological field of the School of Veterinary Medicine and Zootechnics of Mato Grosso do Sul Federal University (UFMS), in Campo Grande, Mato Grosso do Sul, Brazil. The experimental area was composed of 12 plots measuring 18 m² each, planted with Brachiaria brizantha cv. Piatã (Syn. Urochloa brizantha cv. Piatã). The experimental design was completely randomized and the treatments consisted of two defoliation frequencies (with cutting intervals of 28 and 35 days) and two nitrogen levels (100 and 200 kg ha-1 of N, in the form of urea, in a single application ), with three repetitions per treatment. The results showed that for Piatã grass swards established in soil having good fertility, the recommended management strategy is to set the minimum cutting or grazing height at 20 cm, with an interval of 28 days when the grass reaches an approximate height of 30 cm. In swards established in the rainy season, to reduce the fractioning of the N dose, it should be applied in a single dose of up to 100 kg of N ha-1 immediately after the first cutting.

In agricultural crops, the use of swine and poultry waste as organic fertilizers results in gains in the productivity and reduction of production costs, but it may also change the physical properties and mechanical behavior of the soil, either increasing or reducing its quality. This study aimed to investigate the influence of applying increasing doses of liquid swine manure (160 m³ ha-1 year-1, 320 m³ ha-1 year-1 and 480 m³ ha-1 year-1) and poultry litter (6 Mg ha-1 year-1, 12 Mg ha-1 year-1 and 18 Mg ha-1 year-1), along four years, on the physical-mechanical properties and organic carbon content of a very clayey Rhodic Eutrudox. The application of liquid swine manure and poultry litter increased the surface soil organic carbon contents. The soil density decreased, whereas the total porosity and macroporosity increased, with the addition of liquid swine manure and poultry litter. There were no significant changes in the soil susceptibility to compaction.

RESUMO: Popularmente conhecida como pata de elefante ou sussuaiá, Elephantopus mollis, é uma espécie que recentemente surgiu como uma planta daninha em lavouras de cultivos de grãos. Objetivou-se com este estudo avaliar a sensibilidade diferencial de biótipos de E. mollis oriundos de áreas agrícolas e não agrícolas e determinar as melhores combinações de herbicidas aplicados em diferentes estádios de desenvolvimento para o controle desta espécie. Foram realizados três experimentos. No experimento de sensibilidade diferencial foram utilizados dez herbicidas em dois biótipos em duas fases de desenvolvimento. O experimento de dose resposta foi conduzido com oito doses de sete herbicidas. O experimento a campo foi realizado em uma área que apresenta problemas com a planta daninha para validar os resultados dos experimentos anteriores. O biótipo oriundo de área agrícola apresentou menor sensibilidade aos herbicidas quando comparado ao biótipo oriundo de área não agrícola. Os herbicidas de contato inicialmente apresentam controle superior, mas logo a planta apresenta rebrote em função de gemas presentes no colo da planta. A aplicação isolada de 2,4-D com doses entre 1005 e 1675 g e.a ha-1 possui controle de 25%. Quando o 2,4-D é seguido da aplicação de paraquat (400 g i.a ha-1) o controle passa a ser entre 51 e 68%. O melhor tratamento para o controle de plantas desenvolvidas é a mistura de 2,4-D + glyphosate (1340 + 1080 g e.a ha-1) com aplicação sequencial de paraquat.

ABSTRACT: This study aimed to evaluate the antagonistic effect of the mixture ofacetyl coenzyme-A carboxylase (ACCase) enzyme inhibiting herbicides and auxin herbicides in Lolium multiflorum and to determine mechanisms to mitigate this possible effect. The first experiments were conducted by associating the herbicide clethodim (108 g a.i. ha−1), quizalofop-p-ethyl (54 g a.i. ha−1), and clethodim + quizalofop-p-ethyl (108+54 g a.i. ha−1) with 2,4-D (1005 g a.e. ha−1) or triclopyr (720 g a.e. ha−1), in addition to the sole application of the respective graminicides. Another experiment included clethodim (54; 81; 108; 162; 216 g a.i. ha−1), quizalofop-p-ethyl (27; 40.5; 54; 81; 108 g a.i. ha−1), and clethodim + quizalofop-p-ethyl (54+27; 81+40.5; 108+54; 162+81; 216+108 g a.i. ha−1) mixed with 2,4-D (1005 g a.e. ha−1), or triclopyr (720 g a.e. ha−1), in addition to the control treatments without herbicide application. In the second experiment, herbicides clethodim (108 g a.i. ha−1), quizalofop-p-ethyl (54 g a.i. ha−1), and clethodim + quizalofop-p-ethyl (108+54 g a.i. ha−1) in combination with the herbicides 2,4-D (1005 g a.e. ha−1) or triclopyr (720 g a.e. ha−1)had malathion (1000 g a.i. ha−1) or glyphosate (720 g a.e. ha−1) mixed, in addition to the sole applications of the graminicides. The herbicide clethodim + quizalofop-p-ethyl did not present an antagonistic interaction with the auxin herbicides, and obtained 85% weed control. To obtain control similar to the sole application of this graminicide, the dose of the herbicide clethodim needs to be increased by 20%. However, the mixture of the herbicide quizalofop-p-ethyl with 2,4-D and triclopyr affects the ryegrass control. The use of strategies that increase the absorption of ACCase herbicides or the inhibition of P450 enzymes are ways to mitigate the antagonistic effect caused by the association of the two auxin herbicides.

The elucidation of the resistance mechanism of weeds to herbicides is important for management practices. The objective of this work was to investigate the resistance mechanism of glyphosate-resistant C. sumatrensis biotypes by determining the expression levels of the constitutive gene epsps and two ABC transport protein-coding genes designated m7 and m11 with RT-qPCR. Two biotypes of C. sumatrensis were evaluated: one resistant and one susceptible to glyphosate. The treatments consisted of the absence or application of two doses of glyphosate (1,080 and 8,640 g a.e. ha-1). Plant leaves were collected at 1 and 4 days after herbicide application. No difference was observed in epsps gene expression between the studied biotypes. The expression of the m7 and m11 genes revealed that both genes had higher relative expression in the resistant biotype with the application of glyphosate at both doses. The overexpression of the m7 and m11 genes in the resistant biotype treated with glyphosate reveals that these genes play a role in herbicide resistance. These genes may be involved in the sequestration of glyphosate into the vacuole lumen in the resistant C. sumatrensis biotype studied.

A morfogênese de plantas de alho (Allium satvum L.) in vitro é controlada por substâncias adicionadas ao meio de cultivo e por fatores ambientais. Este estudo teve como objetivo avaliar os efeitos da vernalização de bulbilhos e do fotoperíodo no processo de indução de bulbos de alho in vitro. Meristemas caulinares foram excisados de bulbilhos vernalizados por períodos de zero, 30, 60 e 90 dias e submetdos ao cultvo in vitro sob condições de fotoperíodo curto (11h) ou longo (16h). Independentemente do fotoperíodo a que foram expostas, as plantas micropropagadas a partr de meristemas extraídos de bulbilhos vernalizados por 30 a 60 dias apresentaram 100% de taxa de bulbifcação. Detectou-se interação entre fotoperíodo e temperatura apenas para massa fresca de bulbo e para altura de plantas, indicando, portanto, que há dependência entre esses fatores ambientais na micropropagação do alho. O tempo de exposição das plantas ao frio reduz a sensibilidade ao fotoperíodo para a indução da bulbifcação. As plantas de alho cultvadas in vitro apresentam respostas morfogenétcas positvas para a indução e o desenvolvimento de bulbos do tpo dependende de termofotoperíodo.

ABSTRACT The recommendations of nitrogen (N) fertilization in garlic are still based on different varieties of the current types that are infected with phytopathogenic virus. There are several methods for recommendation of nitrogen (N) fertilization in garlic, but there are no enough methods for N diagnosis in garlic obtained by meristem culture. The objective of this work was to evaluate methods for diagnosing the nutritional status of virus-free garlic subjected to N doses through the use of a specific NO3- meter in soil solution and foliar sap, portable chlorophyll meter, N content in the leaf, and its relationship with yield and quality of the bulbs. The experiments were conducted with the use of virus-free seed bulbs from the meristem culture from three sites in the 2015 growing season and two locations in the 2016 growing season in South Brazil. The treatments consisted of the application of five nitrogen doses (0, 100, 200, 300, and 400 kg ha-1) distributed in three applications during the crop cycle: 1/3 in planting, 1/3 between 30 and 40 days after planting, and 1/3 after visual bulb differentiation. The highest commercial yield was associated with doses between 269 and 307 kg ha-1 of N and the content of 26 g kg-1 of N, in the diagnostic leaf. The relative chlorophyll content was the only diagnostic technology that showed a significant correlation with commercial yield in all experimental conditions. The evaluation of the N status in the virus-free garlic crop by a portable chlorophyll meter can be a quick strategy for recommending N fertilization and ensuring high yields.

Abstract: The objective of this work was to compare the structural quality and water retention curve of a Haplustox under single, double, and triple “paricá” (Ochroma pyramidale) lines in an integrated production system at 50 months of implantation. Soil was collected from five sampling points considering the distances from the tree lines. Undisturbed samples were collected from the 0.00-0.10 and 0.10-0.20-m layers in order to assess porosity, density, soil penetration resistance, soil water retention curve, and the “S” index. The forest arrangement based on three paricá lines promoted better soil physical conditions than the system using single lines. The main changes were recorded in the 0.10-0.20-m layer, with increased microporosity and decreased cryptoporosity and resistance to penetration. The arrangements using single and double paricá lines result in higher volume of available water and greater soil compaction.

Abstract: The objective of this work was to evaluate the effect of different amounts of black oat (Avena strigosa) straw covering soil surface on soil temperature at different depths. The treatments consisted of 0, 3, 6, and 9 Mg ha-1 straw. Soil temperature was measured hourly by a thermocouple inserted at different depths (0, 5, 15, 30, and 50 cm) and was used to adjust an equation correlating the temperature of covered soil with that of bare soil. With the correlations, it was possible to observe a point value of temperature (inversion temperature of straw effect), below which the presence of straw acts positively on the maintenance of soil temperature and above which the presence of straw acts negatively on soil heating.

Bovine respiratory disease (BRD) is a complex multifactorial and multi-etiological disease entity that is responsible for the morbidity and mortality particularly in feedlot cattle from North America. Information relative to the occurrence of BRD in Brazil and the associated infectious agents are lacking. This study investigated the participation of infectious agents of BRD in a beef cattle feedlot from Southeastern Brazil. Nasopharyngeal swabs of 11% (10/90) of cattle (n, 450) with clinical manifestations of respiratory distress were analyzed by targeting specific genes of the principal infectious pathogens of BRD. In addition, pulmonary fragments of one the animals that died were collected for histopathological and molecular diagnoses. The nucleic acids of Histophilus somni and bovine respiratory syncytial virus (BRSV) were identified in 20% (2/10) of the nasopharyngeal swabs of the animals with respiratory distress; another contained only BRSV RNA. Moreover, the nucleic acids of both infectious agents were amplified from the pulmonary fragments of the animal that died with histopathological evidence of bronchopneumonia and interstitial pneumonia; the nasopharyngeal swab of this animal also contained the nucleic acids of both pathogens. Additionally, all PCR and/or RT-PCR assays designed to detect the specific genes of Mannheimia haemolytica, Pasteurella multocida, Mycoplasma bovis, bovine viral diarrhea virus, bovine herpesvirus -1, bovine parainfluenza virus-3, and bovine coronavirus yielded negative results. Phylogenetic analyses suggest that the isolates of H. somni circulating in Brazil are similar to those identified elsewhere, while there seem to be diversity between the isolates of BRSV within cattle herds from different geographical locations of Brazil.

O objetivo deste estudo foi desenvolver e validar uma escala diagramática para avaliação da severidade da mancha foliar causada pelo fungo Diplodia macrospora, em folhas de milho, considerando os limites de severidade mínima e máxima da doença e os níveis intermediários de acordo com a "Lei de resposta ao estímulo de Weber-Fechner". A escala proposta apresenta seis níveis de severidade: 0,5%; 3%; 8%; 23%; 36% e 55% da área foliar afetada. A validação foi realizada por oito avaliadores sendo quatro inexperientes e quatro experientes, os quais estimaram a severidade de 60 folhas de milho que apresentavam níveis variados se sintomas da doença, primeiramente sem a utilização da escala diagramática e, posteriormente, com o uso da escala proposta. Pela análise de regressão verificou-se relação entre o grau de severidade real e o estimado por cada avaliador, com e sem o uso da escala. Com a utilização da escala, tanto os avaliadores inexperientes quanto os experientes demostraram maiores níveis de acurácia e precisão.

A pasture composed of the forage Brachiaria brizantha cv. Marandu, for more than 15 years and never fertilized, with an initial condition of degradation, was fertilized with nitrogen and humic substances, with the purpose Of recovering the vigor and productivity of the pasture. In the two years (December of 2012 to April 2013 and December 2014 to April 2015), analyses were made for dry matter production, plant height, light interception, leaf / stem ratio), chemical composition and digestibility of Brachiaria brizantha cv. Marandu. This was a completely randomized block experimental design, in a 5x4 arrangement, with five doses of nitrogen (0, 50, 100, 200, 400 kg N.ha-1), four doses of humic substances (0, 12.5, 25 and 50%), with 5 replicates. The forage presented lower means of dry matter production in the first year in relation to the second, but there was no difference for the chemical composition and digestibility between the years. There was a significant effect of Nitrogen levels on the production of dry matter, crude protein, silica, neutral detergent fiber (NDF), acid detergent fiber (FDA), and in vitro dry matter digestibility (DVMS). The best response was obtained with 200 kg N.ha-1. The doses of humic substances influenced only reducing the leaf/stem ratio, but there was no effect of doses of humic substances on the other variables studied.

Objetivou-se verificar o efeito da aplicação de Nitrogênio mineral (N) na dose de 10 kg por hectare, via solo ou foliar, em diferentes estádios do desenvolvimento da soja. O experimento foi conduzido em área de cultivo comercial de soja, localizado no município de Sinop-MT, em delineamento de blocos casualizados (DBC) com dez tratamentos e quatro repetições. Os tratamentos estudados foram: testemunha sem N, aplicação na semeadura, em V2 a lanço em cobertura, V2 via foliar, V4 a lanço em cobertura, V4 foliar, R1 a lanço em cobertura, R1 foliar, R2 a lanço em cobertura e em R2 foliar. Foram avaliadas as variáveis teor de clorofila, massa seca de parte aérea, numero de nódulos, massa seca de nódulos, número de vagens, número de grãos por vagem, massa de mil grãos e produtividade. Os tratamentos com aplicação de N diferiram da testemunha para todas as variáveis, exceto para teor de clorofila. Para as variáveis número de vagens por planta, número de grãos por vagem, massa de mil grãos e produtividade de grãos todos os tratamentos com aplicação de N foram superiores à testemunha e as maiores respostas foram obtidas quando o N foi aplicado via foliar nos estádios V2 e R1.

ABSTRACT: Quantification of runoff rate is an onerous task with non-automated devices; it requires a lot of manual labor to perform measurements. In this study, an automatic device to quantify the surface runoff rate from plots with a small area was developed and tested. The prototype was based on the tipping bucket technique and built with reused materials. Its performance was tested in the laboratory and a calibration curve was developed to improve measurement accuracy. The device can be used for automatic quantification of surface runoff in small plots, with a flow rate of less than 750 × 103 mm3 min-1. The device can be built with different dimensions to measure different flow rates. In that case, the error measurements and calibration curve must be recalculated.

The combined use of desiccant and residual herbicides is a common management practice under no-tillage systems. However, the effect of desiccant herbicides and mulch on the leaching of residual herbicide is unknown. This study aimed at assessing the leaching of the S-metolachlor herbicide applied to ryegrass sequentially or in association with paraquat or glyphosate. A randomized blocks design was used, with four repetitions and treatments distributed over split-plots. The desiccant herbicides paraquat (600 g ha-1) or glyphosate (720 g ha-1) were used in the main plot, while S-metolachlor (2,800 g ha-1) was applied sequentially or in association with the desiccant herbicides in the subplots. There was also a control containing only desiccant herbicide, with no application of residual herbicide. The type of desiccant did not affect the leaching of the residual herbicide. In addition, the chosen method to apply the residual herbicide, sequentially or in association with the desiccant, did not impact the S-metolachlor behavior in the soil. The bioavailable concentration in the soil, 25 days after the application, was 90 g a.i. ha-1, at a depth of 18 cm.

ABSTRACT: To evaluate the effect of supplementation with mannan oligosaccharides, avilamycin and halquinol, alone or in combination, on the performance, carcass characteristics and antibody production in broilers (1-49 days old), male broiler chicks (n=1440; Cobb 500; one day old) were housed and distributed into a completely randomized design into six treatments (eight replicates; 30 animals per pen). To produce the experimental diets, three types of performance enhancer additives were used. Halquinol (HAL), avilamycin (AVI) and mannan oligosaccharides (MOS) were included (alone or in combination) in the basal diet (instead of corn starch). Effects of diet were observed on results of animal performance in the period 1-21 and 1-42 days old. Broilers fed with a diet without growth promoter showed lower weight gain in relation to those fed with diets with antimicrobials, MOS or a combination of them. In the period 1-49 days old, feed conversion increased in broilers fed with rations without promoter. At the end of the experimental period no influence of diets was observed on the carcass yield and cuts, and titles of specific antibodies to avian infectious bronchitis. The use of MOS and/or antimicrobials (AVI or HAL), alone or in combination, improves feed conversion of broilers reared until 49 days of age.

The Mycosphaerella spot is one of the main foliar diseases of strawberry, degrating great leaf regions and reducing the photosynthetic area. Its control is mainly by the use of chemical fungicides, but, due the increasing demand for food free of pesticide, alternative control methods have been researched, such as biological control. This work aimed to evaluate the effect on strawberry plants, treated with the biological control agents Bacillus cereus, Saccharomyces boulardii and Saccharomyces cerevisiae, in the severity of Mycosphaerella fragariae, productivity and in the activity of β-1.3 glucanases, peroxidases and chitinases enzymes. It was verified that S. cerevisiae and B. cereus treatments were similar to fungicide for disease control. However, even reducing the severity of the disease, there was no increase in productivity, and the different control agents do not cause changes in the evaluated defense mechanisms.

Resumo – O objetvo do trabalho foi avaliar o efeito do parcelamento do adubo fosfatado aplicado no plantio e em cobertura sobre a produtividade do tomateiro ‘Alambra’. O trabalho foi realizado a campo na Epagri, Estação Experimental de Caçador-SC, nas safras 2011/12 e 2012/13. O delineamento experimental foi o de blocos ao acaso, com cinco repetções. Os tratamentos foram constituídos de seis percentagens de P2O5 aplicadas no planto e em cobertura, respectvamente, em relação à dose total deste nutriente (800 kg ha-1): 0 e 100; 20 e 80; 40 e 60; 60 e 40; 80 e 20; 100 e 0%. Como fontes de P foram utilizados o superfosfato triplo para as aplicações no plantio e o fosfato monoamônico purifcado para as aplicações em cobertura. O P em cobertura foi aplicado via fertirrigação, em oito aplicações a partr dos 21 dias até aos 77 dias após o planto. Há acréscimo de produtividades ‘total’, ‘comercial’ e classe ‘extra AA’ de frutos de tomateiro na medida que se aumenta a porcentagem de P incorporada no plantio, em relação a aplicação em cobertura via fertirrigação, com a maior produtividade obtida com 100% do P aplicado no plantio. Abstract – The objective of this work was to evaluate the effect of the phosphate fertilizer applied in the planting and in the sidedressing on the yield of ‘Alambra’ tomato. The experiments were carried out in the field at Epagri, Experimental Station of Caçador-SC, in the 2011/12 and 2012/13 harvests period. The experimental design was a randomized block design, with five replications. The treatments were composed of six percentages of P2O5 applied to planting and covering, respectively, in relation to the total dose of this nutrient (800 kg ha-1): 0 and 100; 20 and 80; 40 and 60; 60 and 40; 80 and 20; 100 and 0%. As P sources, triple superphosphate was used for planting applications and purified monoammonium phosphate for fertigation applications. The P in fertigation was applied in the amount corresponding to the percentage predicted for each treatment, via fertigation, in eight applications from 21 days to 77 days after planting. There is an increase in ‘total’, ‘marketable’ and ‘extra AA’ yields of tomato fruits as the percentage of P incorporated in the planting is increased, compared to the application in sidedressing via fertirrigation, with the highest productivity obtained with 100 % of P applied at planting.

ABSTRACT Water and oxygen deficiencies in the soybean crop cultivated on lowland soils are an important topic of research. The objective of this study was to investigate changes in water and oxygen supply and soybean yield caused by soil management in lowland soils. A soybean crop was grown under four soil conditions: no-tillage (NT), chiseling (CH), ridge tillage on no-tillage (NTR), and ridge tillage on chiseling (CHR). Soil bulk density, total porosity, macro- and microporosity, air permeability, and saturated hydraulic conductivity were measured at 0.05, 0.15, 0.25, and 0.35 m depths. Soil volumetric water content was monitored at the same depths every 30 min during the soybean cycle. The transpiration coefficient was calculated from volumetric water content to express both water and oxygen deficiency. The groundwater level was monitored throughout the soybean cycle. Plant performance was evaluated by measuring plant population, shoot dry matter, yield, and taproot depth. Soil porosity, air permeability, and saturated hydraulic conductivity were most improved in CH and CHR, and less in NTR. Nonetheless, expected improvement in soil aeration in CH, CHR, and NTR was eliminated when the water table raised to near the soil surface. The transpiration coefficient indicated that CH decreased oxygen deficiency, but caused little water deficit. The CH also provided the highest yield (4,610 kg ha-1), which was not surpassed by the addition of ridge tillage on chiseled soil (CHR) (4,001 kg ha-1). The lowest yields were observed in NT (2,842 kg ha-1), and NTR (3,565 kg ha-1), in which oxygen deficiency was more severe. Lower oxygen deficiency for soybean in chiseled lowland soil is regulated by the water table. As the transpiration coefficient is dependent on all the processes determining soil water dynamics, it is more informative than soil structural properties regarding water and oxygen deficiency in soybean in lowland soil.

Aplicação via solo e foliar de fertilizantes formulados com cálcio (Ca) e boro (B) é prática comum para prevenção de distúrbios fisiológicos em tomates. Objetivou-se avaliar o efeito da aplicação de formulações de Ca e B e ácido bórico via foliar, e de bórax via solo, em tomateiro de mesa, em Caçador, SC, nas safras 2010/11, 2011/12 e 2012/13. No início da maturação dos frutos, determinou-se macro e micronutrientes na folha diagnose. Na colheita, avaliou-se a produtividade total, comercial (extra AA e extra A) e descarte, e a incidência dos distúrbios fisiológicos podridão apical e lóculo aberto. As aplicações de Ca e B não influenciaram a produtividade e a incidência de distúrbios fisiológicos. Não se observou sintomas de deficiência ou toxidez nas plantas que apresentaram teores foliares de nutrientes abaixo ou acima da faixa recomendada para a cultura. A aplicação foliar de B, como ácido bórico, aumentou o teor de B na folha diagnose, porém sem efeito na produção e na incidência de lóculo aberto nos frutos.

ABSTRACT: Blast, caused by Pyricularia oryzae, threats black (Avena strigosa) and white (A. sativa) oats in Brazil. Little is known about the reaction of Brazilian oat cultivars to blast and if there is a relationship between the response of cultivars to the disease at seedling and adult plant stages. The goals of this research were to verify (a) the reaction of black and white Brazilian oat cultivars to infection of P. oryzae and (b) if the response to blast on seedling leaves and panicles was correlated. Seedlings and adult plants of 13 oat cultivars were inoculated with a conidial suspension of one P. oryzae isolate obtained from a black oat cultivar. The cultivars were classified according to blast severity on the leaf seedlings and panicles estimated by visual estimation. Two experiments were conducted for each one of the two evaluated stages. Cultivars with lower value to blast severity on seedling leaves were ‘UPFA Gaudéria’ (25.82%) and ‘UPF 18’ (24.88%) and, on panicles, ‘BRS Centauro’ (31.63%). Coefficients of Pearson, Spearman, and Kendall obtained from correlation analyses between blast severity on seedling leaves and panicles were -0.21232, -0.35714, and -0.30769, respectively (non-significant at 0.05). Lack of correlation between the responses of these oat cultivars to blast on seedling leaves and panicles be considered in the management of the disease in the field and the generation of new oat cultivars.

The objective of this study was to evaluate the supply of supplement of protein and supplement mineral in the rearing of crossbred steers Holstein x Zebu ½ maintained on Brachiaria brizantha. Marandu, in the rainy season and its implications on intake, nutrient digestibility and animal performance. Were used 22 steers averaging seven months of age and mean initial body weight of 164.09 ± 12.13 kg, distributed in a completely randomized design with two types of supplement and eleven repetitions per supplementation. The intake of dry matter (DM) total and of the nutrients had higher averages for animals receiving supplement of protein/energy. The use of supplement of protein/energy has improved digestibility of the nutrients of, except for the digestibility of neutral detergent fiber corrected for ash and protein (NDFap). The animals that received supplement of protein/energy presented better performance when compared to those receiving supplementation mineral. The use of supplement of protein/energy in the rainy season provides major input of nutrients, improves digestibility of nutrients and performance of crossbred steers reared in Brachiaria brizantha.

The leaf “frog-eye” spot is a disease that often occurs in Argentina and Brazil is becoming important in soy producing regions. The difficulty in achieving inoculum for studies with P. sojina led to the development of this work was to determine the sporulation of races P. sojina in different culture media and light regimes and check difference in sporulation of races of this fungus. The plates with the culture media BDA, STT , AI , V8 and FAA containing the three races of P. sojina were subjected to a photoperiod of 12/12 h (light and dark) and continuous dark. The experimental design was a factorial 5x2x3 (culture medium, light regimes, races of P. sojina) with four replications. The greatest number of conidia cm- 2 of the fungus was found for race 23 in the middle of STT culture and races 24 e 25 in the middle of V8 culture. The fungus race 25, with the largest number of conidia cm-2, regardless of the medium and the light regimen. With respect to light regime for all races of the fungus, the largest esporulation were checked at a photoperiod of 12/12 h. When the fungus was grown in culture medium AI, this had the largest area of the colony, regardless of breed fungus and light regime

Nos sistemas de produção do morangueiro, a adubação com boro é uma das práticas culturais mais empregadas pelos produtores, contudo o seu uso de forma incorreta pode comprometer a produção e a qualidade das frutas. O objetivo da presente pesquisa foi avaliar os efeitos da aplicação de boro no solo (0 e 4kg ha-1) combinada com pulverizações na parte aérea das plantas (0, 240, 480, 720 e 960g B ha-1) sobre a planta, número, produção, acidez titulável, teor de sólidos solúveis, pH da polpa e firmeza das frutas do morangueiro. A aplicação de 4kg B ha-1 no solo proporcionou redução da produção de massa seca radicular e aérea das plantas de morangueiro. A aplicação foliar de boro aumentou o número e a produção de frutas com maior diâmetro, e a máxima produção total de frutas foi obtida com a aplicação foliar de 568g B ha-1 durante o período reprodutivo. Tanto a aplicação de boro na parte aérea quanto no solo aumentaram o teor foliar deste nutriente, sendo que o teor foliar adequado para a segunda florada do morangueiro oscilou entre 69 a 88mg kg-1. A aplicação foliar de boro aumentou a firmeza das frutas, porém independentemente da forma de aplicação de boro houve redução no teor de sólidos solúveis das frutas do morangueiro.

Protocolos eficientes de crescimento de ápices caulinares de alho (Allium sativum L.) e posterior bulbificação in vitro são importantes para limpeza clonal e manutenção da fidelidade genética. O trabalho teve como objetivo avaliar os efeitos de tipos e concentrações de reguladores de crescimento sobre a morfogênese de plantas de alho in vitro. Ápices caulinares com até dois primórdios foram excisados de bulbilhos de alho da cv. 'Jonas' e submetidos ao cultivo in vitro em meio de cultura suplementado de ácido indolacético (0; 1,07; 2,69 e 5,37µM), ácido indolbutírico (0; 0,49; 0,98 e 2,46µM), ácido naftalenoacético (0; 1,07; 2,69 e 5,37µM), ácido jasmônico (0; 1,0; 5,0 e 10,0µM) e ácido abscísico (0; 0,38; 1,89; e 3,78µM). A concentração de 1,07µM de ácido naftalenoacético aplicado ao meio de cultura promoveu incrementos na maioria das variáveis analisadas. O ácido jasmônico induziu a formação de bulbos de alho in vitro, embora tenha apresentado performance inferior ao verificado com o uso de ANA. Por outro lado, a adição de ácido abscísico no meio de cultura inibiu o crescimento de plantas, porém, não impediu a formação de bulbos, sobretudo em concentrações reduzidas. De um modo geral, as variáveis número de bulbos e porcentagem de bulbificação diminuiram com o uso de concentrações elevadas dos reguladores de crescimento testados. Entre os reguladores de crescimento de plantas, o ANA apresenta maior efeito na morfogênese in vitro de plantas de alho, entretanto, o ácido jasmônico e o ABA também apresentam potencial para induzir a formação de bulbos de alho in vitro como o ANA.

Black root rot, caused by Macrophomina phaseolina (Tass.) Goid., is the most common root disease in soybean fields. This study aimed to determine the in vitro mycelial sensitivity, measured by the IC50 (concentration to inhibit 50% of the fungus mycelial growth) of a M. phaseolina isolate obtained from soybean, to different fungicides (thiram, iprodione, carbendazim, pyraclostrobin, fluquinconazol, tolyfluanid, metalaxyl and penflufen + trifloxystrobin), at six concentrations (0.01 mg L-1, 0.10 mg L-1, 1.00 mg L-1, 10.00 mg L-1, 20.00 mg L-1 and 40.00 mg L-1 of the active ingredient). The 0.00 mg L-1 concentration represented the control, without fungicide addition. The mycelial growth evaluation was performed with the aid of a digital pachymeter, by measuring the colonies diameter, when the fungus growth in the control treatment reached the Petri dish edge. The experimental design was completely randomized, with four replications. Concerning the fungitoxicity of active ingredients, a variation from non-toxic to highly fungitoxic was observed to the M. phaseolina isolate, with IC50 values ranging from 0.23 mg L-1 to > 40.00 mg L-1, being carbendazim the most efficient one (IC50 = 0.23 mg L-1). The fungus showed insensitivity to the active ingredients of fluquinconazole, metalaxyl, thiram and tolyfluanid.

The value of soil water infiltration is very important in several areas, such as agriculture, water resources, engineering projects. The methods to determinate the water infiltration in general is difficult and produce often unreliable results. The work aimed to evaluate the soil water infiltration rate in a Rhodic Hapludox under three management systems. The results were compared using two methods to determine the water infiltration rate. In the three management systems, the water infiltration rate in the soil was determined using the double ring infiltrometer. Using this method the results showed higher values when compared to the Cornell infiltrometer. For both methods, the native forest presented the highest soil water infiltration rate, followed by the no tillage area and perennial pasture grown. Through the double ring infiltrometer the infiltration rates obtained were 1428.2 mm h-1 (Forest), 46 mm h-1 (no tillage) and 22.6 mm h-1 (perennial pasture). Considering the Cornell infiltration method, the same areas showed infiltration rates of 300, 33.2 and 12.7 mm h-1, respectively. In the native forest the runoff process was not verified, while ingress with no tillage and perennial pasture. In these areas the runoff is started, respectively, at 3.25 and 1.33 minutes after the beginning of the tests.

The majority of Arecaceae species presents difficulties to germinate, even under appropriate conditions, complicating the seedlings production process. This study aimed at evaluating the influence of seed scarification and soaking in the emergence and development of Mauritia flexuosa seedlings. The treatments consisted of a combination of seed soaking and scarification methods, in a completely randomized design, in a 2 x 3 + 1 factorial scheme, with five replications. Seeds with and without scarification, combined with soaking methods (not soaked seeds and seeds soaked for 30 days, with and without daily water renewal), plus an additional treatment, where the seeds were scarified after soaking for 30 days, were tested. The seedlingemergence up to 146 days after sowing (d.a.s.) was evaluated, as well as the emergence rate index (46 and 146 d.a.s.) and growth components (146 d.a.s.). The results were submitted to the variance analysis (F test) and means compared by using the Tukey test, at 5%. It was possible to conclude that the Mauritia flexuosa seeds presented tegument dormancy. The seed scarification increased the germination rate, however, it contributed to increase the seeds mortality rate. The soaking of nonscarified seeds for 30 days, with daily water renewal, improved the potential for seed germination. The mechanical scarification, without or after soaking the seeds in water, increased the Mauritia flexuosa seedlings mortality rate, and it is not, therefore, a suitable method for dormancy breaking. = A maioria das espécies de Arecaceae apresenta dificuldades para germinar, mesmo sob condições adequadas, dificultando a produção de mudas. Objetivou-se, com este trabalho, avaliar a influência da escarificação e embebição de sementes na emergência e desenvolvimento de mudas de buritizeiro. Os tratamentos foram compostos pela combinação de métodos de embebição e escarificação de sementes, adotando-se o delineamento inteiramente casualizado, no esquema fatorial 2 x 3 + 1, com cinco repetições. Foram testadas sementes com e sem escarificação, combinadas com métodos de embebição (sementes não embebidas e sementes embebidas por 30 dias, com e sem renovação diária de água), além de um tratamento adicional, onde as sementes foram escarificadas após a embebição por 30 dias. Foi avaliada a emergência de plântulas aos 46, 66, 86, 106, 126 e 146 dias após a semeadura (DAS), bem como o índice de velocidade de emergência (46 e 146 DAS) e os componentes de crescimento (146 DAS). Os resultados foram submetidos à análise de variância (Teste F) e as médias comparadas pelo teste Tukey, a 5%. Concluiu-se que as sementes de buriti apresentam dormência tegumentar. A escarificaçãode sementes aumenta a velocidade de emergência, entretanto, contribui para o aumento na taxa de mortalidade das sementes. A embebição de sementes não escarificadas por 30 dias, com renovação diária de água, melhora o potencial germinativo das sementes. A escarificação mecânica, sem ou após a embebição das sementes em água, aumenta a mortalidade de plântulas de buritizeiro, não sendo, portanto, um método adequado para a superação de dormência.

Due to the expansion of sugarcane in areas that are not traditional in it’s cultivation, there is need of study the management of fertilizer, mainly phosphorus, since it’s the nutrient that most limits the production in the tropics. The aim of this work was to evaluate the productivity and nutritional value of two varieties of sugarcane grown under different phosphorus sources, for three production cycles in North of Mato Grosso State, Brazil. The experimental design was randomized blocks in factorial scheme 4x2, with four replications. The sources of phosphorus used were bone meal, Arad phosphate and triple superphosphate at a dose of 100 kg P2O5 ha-1, and a control without nutrient application at planting. The varieties of sugarcane were planted IAC86-2480 and SP79-1011. We evaluated the productivity of dry matter, dry matter content, neutral detergent fiber and acid detergent, lignin, cellulose, in vitro digestibility and crude protein of forage. The phosphorus sources provided higher yields during the first cycle of sugarcane and did not cause significant effect on productivity in subsequent cycles. Phosphorus fertilization did not cause significant changes in the nutritional value of sugarcane. The variety IAC86- 2480 showed higher crude protein content in three cycles and higher dry matter yield in the first two cycles, compared to SP79-1011. Regarding the fiber constituents, both showed similar results. Com a expansão da cana-de-açúcar em áreas nas quais não é tradicional seu cultivo, há a necessidade de se estudar o manejo da adubação, principalmente do fósforo, que é o nutriente que mais limita a produção em regiões de clima tropical. O objetivo deste trabalho foi avaliar a produtividade e o valor nutricional de duas variedades de cana-de-açúcar cultivada com diferentes fontes de fósforo, durante três ciclos de produção no Norte do Mato Grosso. O delineamento experimental utilizado foi o de blocos ao acaso, em esquema fatorial 4x2, com quatro repetições. As fontes de fósforo utilizadas foram a farinha de ossos, fosfato de Arad e superfosfato triplo, na dose de 100 kg ha-1 de P2O5 e, um controle, sem aplicação do nutriente no sulco de plantio. As variedades de cana-de-açúcar plantadas foram a IAC86-2480 e a SP79-1011. Avaliou-se a produtividade de matéria seca, teor de matéria seca, fibra em detergente neutro e, em detergente ácido, lignina, celulose, digestibilidade in vitro e proteína bruta da forragem. As fontes de fósforo proporcionaram maiores produtividades durante o primeiro ciclo da cana-de-açúcar e não causaram efeito significativo na produtividade nos ciclos posteriores. A adubação fosfatada não promoveu alterações significativas no valor nutricional da cana-de-açúcar. A variedade IAC86-2480 apresentou maior teor de proteína bruta nos três ciclos e maior produtividade de matéria seca nos dois primeiros ciclos, em relação a SP79-1011. Em relação aos constituintes fibrosos, ambas as variedades apresentaram resultados semelhantes.

Resumo: O trabalho foi realizado na Epagri/Estação Experimental de Caçador com o objetivo de avaliar o efeito de fontes de nitrogênio (N) e potássio (K) aplicados via fertirrigação sobre a produção de tomate de crescimento indeterminado. O delineamento experimental foi blocos ao acaso, com quatro repetições, sendo oito e dez tratamentos nas safras 2007/08 e 2008/09 respectivamente. Determinaram-se os teores foliares de N, P, K, Ca, Mg, Fe, Zn, Cu, Mn e B na folha diagnóstica. Na colheita, avaliou-se a produtividade total e comercial classificando os frutos em extra AA, extra A e descarte. As fontes de nutrientes utilizadas nas duas safras não influenciaram a produtividade do tomate, que foi próxima de 100t.ha-1. Isso permite escolher a fonte segundo sua praticidade de preparo e aplicação via fertirrigação e de acordo com o custo por unidade de nutriente aplicado. Para todos os teores foliares de nutrientes que estavam abaixo ou acima da faixa recomendada para a cultura não se observaram sintomas de deficiência ou toxidez nas plantas. Abstract: This work was carried out at EPAGRI - Experimental Station of Caçador, SC, to evaluate the production of tomatoes as a function of sources of nitrogen (N) and potassium (K) applied by fertigation. The experimental design was randomized blocks, with four replications and 8 and 10 treatments in the growing seasons 2007/08 and 2008/09, respectively. Leaves were analyzed for the nutrients N, P, K, Ca, Mg, Fe, Zn, Cu, Mn and B. The total and the marketable production was obtained by classifying the fruits into extra AA, extra A and unmarketable. In both crops, the mean total production was close to 100 t ha-1, independent of the source of N and K used. This allows to choose the source according to their preparation and application by fertigation, and according to the cost per unit of nutrient applied. Visual symptoms of deficiency or toxicity were not observed when the leaf content of a nutrient was below or above the normal range of concentration.

A similaridade botânica do capim-annoni com as espécies forrageiras nativas ou cultivadas dificultam o seu controle em pastagens naturais. O objetivo deste trabalho foi avaliar o efeito de associações entre herbicidas e protetores sobre o controle de capim-annoni e a seletividade em pastagem natural. Foram realizados dois experimentos a campo em área de pastagem natural típica do Bioma Pampa avaliando-se herbicidas aplicados em pré e pós-emergência. Outro experimento foi conduzido em casa de vegetação com as espécies capim-annoni e grama forquilha onde foram avaliados os herbicidas glufosinate-ammonium e imazethapyr. Em ambos os experimentos os herbicidas foram avaliados isolados ou em associação com os protetores anidrido naftálico, dietholate e fluxofenim. Os experimentos a campo demonstraram que os herbicidas aplicados em pré ou pós-emergência em interação com os protetores não proporcionaram controle satisfatório do capim-annoni e nem aumento da seletividade à pastagem natural. Por outro lado, o experimento em condições controladas indicou a ocorrência de sinergismo do herbicida glufosinate-ammonium em interação com os protetores anidrido naftálico, dietholate e fluxofenim sobre o capim-annoni. As diferenças relacionadas a estádio de desenvolvimento e densidade de infestação estão relacionadas as variações das respostas nos estudos a campo e em condições controladas. A utilização de herbicidas em associações com protetores apresenta potencialidade de controle seletivo de capim-annoni quando aplicado em plantas em estádios iniciais de desenvolvimento.The botanical similarity of the invasive weed Eragrostis plana Nees (South African lovegrass) difficult its selective control in natural pastures. The aim of this study was to evaluate the effect of the association between herbicides and safeners on the control of E. plana and on the selectivity to the natural pastures. Two experiments were conducted at field conditions in area of natural grassland of the Biome Pampa where several herbicides were evaluated in pre and post-emergence. A third experiment was carried out in greenhouse evaluating the herbicides glufosinate-ammonium and imazethapyr and the species E. plana and Paspalum notatum. In both experiments, the herbicides were evaluated isolated and in association with the safeners anhydride naphtalic, dietholate and fluxofenim. The field experiments indicated that the evaluated safeners did not increase E. plana control and native grassland selectively. The greenhouse experiment indicated the occurrence of synergism on E. plana for the herbicide glufosinate-ammonium in mixture with the safeners anhydride naphtalic, dietholate and fluxofenim. The different results in the field and greenhouse experiments are related to the plant stage and density. The use of herbicides in association with safeners indicated a potentiality for selective control of E. plana when applied to plants in the early stages of development.

El objetivo de este trabajo fue evaluar los efectos de dosis de N y K2O, vía fertirrigación por goteo, y de la distancia entre plantas sobre la productividad del híbrido Shadow de sandía sin semillas. El experimento se realizó de agosto a octubre de 2008 en el Município de Tupã, SP, Brazil. Se avaluaran cuatro dosis de N + K2O (79,8 + 106,7, 106,4 + 142,2, 133,0 + 177,7, y 159,6 + 213,2 kg ha-1, respectivamente), y cuatro distancias entre plantas (0,5, 1,0, 1,5 y 2,0 m), en hileras espaciadas de 2,0 m. Se utilizó el diseño experimental de bloques al azar, en parcelas subdivididas, con tres repeticiones. Las variables evaluadas fueron: concentración foliar de N y K, peso medio de frutos, número de frutos y productividad total y comercial; y número de frutos en las clases de 3 a 5, 5 a 7, 7 a 9 kg y con más de 9 kg, por planta y por hectárea. Hubo efecto del factor dosis de N + K2O sobre la concentración foliar de K, y la productividad total y comercial de la sandía híbrido Shadow disminuyó linealmente con el aumento de la distancia entre plantas. Sin embargo, no hubo efecto significativo de la interacción ni efecto individual de los factores sobre las otras variables avaliadas.

This study aimed to identify and quantify the causal agents of fungal leaf blights, and compare different assessment methods for disease quantification. The experiments were conducted with 20 medium cycle cultivars in Passo Fundo, Saint Augustus and Vacaria counties with three replications in randomized blocks. For evaluation 20 leaves were collected per plot, at flowering stage. Disease severity was estimated by the percent diseased leaf area and lesions number per leaf. For fungus etiology, twenty five discs of each leaf sample containing a lesion were subjected to a humid chamber. After three days incubation fungi identification was performed under a dissecting microscope. The mean incidence, number of lesions and severity data were subjected to analysis of variance and means compared by the Tukey’s multiple test at 5% significance level. The severity and lesions number were the most efficient criteria to fungal foliar disease, predominantly Bipolaris sorokiniana, Drechslera siccans, D. tritici-repentis and Stagonospora nodorum. The cultivars with the highest incidence rates were not the same as that presented the greatest number of injuries and severity. Join the appearance D. siccans and the resurgence of S. nodorum.

Um dos fatores da baixa produtividade está na dificuldade de se estabelecer a população ideal de plantas por ocasião da semeadura, pelos vários fatores que impedem a germinação normal de parte das sementes. Dentre os fatores primordiais para a germinação estão a umidade, a temperatura e a aeração do solo. É importante citar que estes fatores são diretamente influenciados pelo estado de compactação do solo ao redor da semente. O presente trabalho teve como objetivo estudar os efeitos da combinação entre profundidades desemeadura e cargas aplicadas pela roda compactadora da semeadora-adubadora sobre a emergência e o desenvolvimento da cultura do feijão, em sistema de plantio direto. Foi utilizado o esquema fatorial, no delineamento em blocos ao acaso composto por 12 tratamentos (três profundidades de semeadura e quatro níveis de cargas aplicadas pela roda compactadora) e quatro repetições. Os resultados mostraram que a semeadura realizada a 5,0 cm de profundidade apresentou o melhor índice de velocidade-emergência, quando comparada às profundidades de 3,0 e 7,0 cm.One of the factors of low productivity is the difficulty of establishing the ideal population of plants at sowing time, due to the several factors that prevent the normal germination of part of the seeds. Among the primordial factors for germination are humidity,temperature, and airing of the soil. It is important to mention that these factors are directly influenced by the state of soil compaction around the seed. The present work aimed to study the effects of the combination between depths of sowing and loads applied by press wheel of the seeder on the emergence and development of bean culture, in no-tillage systems. The factorial scheme was applied, at the delineation in random blocks composed of twelve treatments (threedepths of sowing and four levels of loads applied by the press wheel) and four replications. The results showed that the sowing performed at 5.0 cm of depth presented the best index of speed emergence when compared to the depths of 3.0 and 7.0 cm.

This study aimed to identify and quantify the causal agen ts of fungal leaf blights, and compare different assessment methods for disease quantification. The experiments were conducted with 20 medium cycle cultivars in Passo Fundo, Saint Augustus and Vacaria counties with three replications in randomized blocks. For evaluation 20 leaves were collected per plot, at flowering stage. Disease severity was estimated by the percent diseased leaf area and lesions number per leaf. For fungus etiology, twenty five discs of each leaf sample containing a lesion were subjecte d to a humid chamber. After three days incubation fungi identification was performed under a dissecting microscope. The mean incidence, number of lesions and severity data were subjected to analysis of variance and means compared by the Tukey’s multiple te st at 5% significance level. The severity and lesions number were the most efficient criteria to fungal foliar disease, predominantly Bipolaris sorokiniana, Drechslera siccans, D. tritici - repentis and Stagonospora nodorum . The cultivars with the highest in cidence rates were not the same as that presented the greatest number of injuries and severity. Join the appearance D. siccans and the resurgence of S. nodorum.

A aplicação de nitrogênio no milho de forma antecipada, tanto na semeadura da planta de cobertura como em pré-semeadura pode otimizar os trabalhos dentro da propriedade. Objetivou-se avaliar a influência nas concentrações foliares e produtividade de grãos do milho do parcelamento do nitrogênio suplementar à semeadura em área de dois anos de soja, em solo de textura média e quantificar a recuperação do nitrogênio do sulfato de amônio e da úreia, utilizando a técnica da diluição isotópica (15N). Os tratamentos constaram da aplicação de 110 kg ha-1 de nitrogênio em épocas distintas: na semeadura do milheto -5 dias antes da semeadura do milho -em cobertura, quando as plantas tinham 5-7 folhas; -e em cobertura quando as plantas tinham 9-10 folhas. Há diferença de produtividade de grãos e concentrações foliares de nitrogênio, fósforo, cálcio e enxofre quando se aplica nitrogênio suplementar à semeadura em diferentes épocas em relação a ausência de fertilização. O parcelamento de 110 kg ha-1 entre pré-semeadura e cobertura ou apenas na cobertura não altera a recuperação total do fertilizante. A recuperação do nitrogênio do sulfato de amônio aplicado em cobertura é maior quando comparada à uréia, sendo ainda que o parcelamento de sulfato de amônio em cobertura apresenta maior recuperação em relação ao fornecimento em uma única aplicação.

Diversos biótipos de sagitária (Sagittaria montevidensis Cham. & Schlecht) foram constatados como resistentes a herbicidas inibidores da enzima ALS no Brasil e em outros locais do mundo. Os objetivos deste trabalho foram isolar e sequenciar o gene ALS de sagitária de forma a identificar a ocorrência de mutações relacionadas ao mecanismo de resistência de insensibilidade do local da ação de herbicidas. O material vegetal consistiu de sementes de sagitária coletadas em lavouras de arroz irrigado localizadas na região Sul do Estado de Santa Catarina. Nove pares de sequências nucleotídicas iniciadoras foram desenhadas para a amplificação dos domínios C, A e D do gene ALS. As sequências nucleotídicas dos fragmentos amplificados com quatro pares de oligonucleotídeos inciadores resultaram em amplicons com 360 a 393 nucleotídeos. Essas sequências apresentaram homologia com o gene ALS padrão de Arabdopsis thaliana e arroz, possuindo apenas três mutações de ponto. Uma dessas alterações foi a mutação Pro197Phe, que é relacionada à ocorrência de resistência à herbicida em diversas espécies vegetais. As sequências obtidas evidenciaram que o gene ALS avaliado encontrava-se em heterozigose. Esses resultados sugerem a ocorrência de insensibilidade do local de ação como mecanismo de resistência a herbicidas inibidores de ALS em sagitária. A prevenção e o controle da resistência a herbicidas inibidores da ALS em sagitária devem ser fundamentados na rotação de herbicidas com diferentes mecanismos de ação.California arrowhead (Sagittaria montevidensis Cham. & Schlecht) is an aquatic weed often found in rice paddy fields. Several biotypes of California arrowhead resistant to ALS-inhibiting herbicides were found in Brazil and in several rice fields worldwide. The objective of this study was to sequence the ALS gene of California arrowhead and to identify the occurrence of mutations related to target site insensitivity as the mechanism of herbicide resistance. The plant material consisted of seeds collected in rice paddy fields located in the state of Santa Catarina, Brazil. Nine pairs of primers were designed for the amplification of the domains C, A and D of the ALS gene. PCR reactions with four pairs of primers resulted in amplification of fragments with size close to expected, ranging from 360 to 393 nucleotides. These sequences showed high homology to the standard ALS gene Arabdopsis thaliana and rice having only three point mutations. One of these mutations was Pro197Phe that is related with herbicide resistance in several weeds. The sequences obtained indicated that the ALS gene evaluated was heterozygous. These results suggest the occurrence of insensitivity of the site of action as the mechanism of resistance to ALS-inhibitors herbicides in California arrowhead. The prevention and control of resistance to ALS-inhibitors in California arrowhead should be based on the rotation of herbicides with different mechanisms of action.

Métodos de representação espacial para o cálculo do fator topográfico (LS) da Equação Universal de Perda de Solo Revisada (RUSLE) têm sido utilizados para estimar a erosão do solo e a produção de sedimentos em bacias hidrográficas. Esses procedimentos baseiam-se nas equações tradicionalmente empregadas para determinação do fator LS e em informações que caracterizam a forma das vertentes derivadas do modelo numérico de elevação (MNE). Neste estudo foram analisados dois métodos de representação espacial utilizados no cálculo do fator LS em modelos matemáticos de erosão e produção de sedimentos em bacias hidrográficas. A análise foi realizada em quatro bacias rurais de relevo movimentado. Os valores de LS obtidos pelos métodos de representação espacial foram comparados entre si e com valores de LS determinados pelo método tradicional com levantamento em campo. Resultados mostraram que os valores de LS gerados pelos métodos de representação espacial apresentam diferenças significativas entre si, sendo dependentes do procedimento de cálculo e do método utilizado para determinar a direção de fluxo no MNE. Também foi verificado que os valores numéricos do fator LS determinados pelos métodos de representação espacial apresentam diferenças em relação àqueles estimados pelo método tradicional.Methods of spatial representation to calculate the topographic factor (LS) of the Revised Universal Soil Loss Equation (USLE) have been used to estimate soil erosion and sediment yield of watersheds. These procedures are based on equations traditionally used to determine the LS factor and information that characterize the hillslope forms and processes, derived from the Digital Elevation Model (DEM). Two computational methods commonly used to calculate LS factor in soil erosion and sediment yield models were analyzed in this study. The analysis was performed in four small rural watersheds with hilly terrain. The LS values obtained by the methods of spatial representation were compared with each other with LS values measured by the traditional method. Results show significant differences of the computer-generated LS values, which were related to the calculation procedure and the method used to determine the DEM flow direction. Differences were also observed between the numeric values of the LS factor determined by methods of spatial representation and in the field.

Dentre os fatores primordiais para a germinação estão a umidade, a temperatura e a aeração do solo. É importante citar que esses fatores são diretamente influenciados pelo estado de compactação do solo ao redor da semente. Objetivou-se, neste trabalho, estudar os efeitos da combinação entre profundidades de semeadura e cargas aplicadas pela roda compactadora da semeadora-adubadora sobre o desenvolvimento da cultura do feijão, em sistema plantio direto. Foi utilizado o esquema fatorial no delineamento em blocos ao acaso, composto por doze tratamentos (três profundidades de semeadura e quatro níveis de cargas aplicadas pela roda compactadora) e quatro repetições. Os resultados mostraram que a profundidade de semeadura influenciou, significativamente, o índice de velocidade de emergência, os estandes inicial e final de plantas e o rendimento da cultura. As diferentes cargas aplicadas pela roda compactadora não influenciaram significativamente as variáveis avaliadas.Among the primordial factors for the germination are humidity, temperature, and aeration of the soil. It is important to mention that these factors are directly influenced by the soil compaction state around the seed. The present paper had the aim of studying the effects of the combination between depths of sowing and loads applied by press wheel of the seeder upon the development of bean culture, in a no-tillage system. Factor schedule was applied to the delineation in random blocks composed by twelve treatments (three depths of sowing and four levels of loads applied by the press wheel) and four replications. The results showed that depth of sowing significantly influenced the index of emergency speed, the initial and final stands of plants and yield of culture. The different loads applied for the press wheel did not significantly influence the evaluated variables.

Locomotion deficiencies in broiler production cause poor welfare and lead to change in drinking and feeding behavior with consequent loss in weight gain. This research aimed to assess locomotion deficiencies in broiler chicken by analyzing the vertical peak force on both feet during walk. A chamber was built with an inlet ramp, a horizontal walkway in the middle and an outlet ramp. In the walkway a thin mat with piezoelectric crystal sensors was placed to record the step vertical peak force of the feet while walking on the force platform. The measurement system consisted of a mat with electronic sensors and software that allowed real time recording of the forces and the processing and analysis of data. Footage was taken from two digital video cameras and used for gait scoring. Forty male broilers were chosen at random, grown under similar rearing conditions and farms, with age varying from 49 to 28 days (ten birds of same age) to be used in the trial. Measurement consisted of inducing the bird to walk on the force platform which automatically registered the peak vertical force of the steps. Results showed that the gait score increased with the weight and age of the birds. Peak force asymmetry was found for each foot, independent of age or gait score. Although not identified visually in the broilers, the peak vertical force values differed in both right and left feet leading to slow and uneven walking. Walking deficiency was more severe in older birds.Deficiência em locomoção é hoje um dos problemas mais importantes na produção de frangos de corte. É causa de baixo bem-estar e leva a alteração no comportamento de bebida e alimentação, com conseqüente perda de ganho de peso. Mediram-se deficiências locomotoras em frango de corte por meio da análise do pico de força plantar vertical em ambas as patas, durante a caminhada. Foi construída uma câmara com uma rampa de entrada, uma área horizontal de passagem e uma rampa de saída. Na parte horizontal da área de passagem foi colocado um tapete fino, com elementos sensores de cristal piezoelétrico, para registrar o pico de força vertical das patas do frango quando este caminhava sobre a plataforma. O sistema de mensuração consistiu de um tapete com sensores eletrônicos e um programa computacional que permitiu o registro de forças em tempo real e o processamento e a análise de dados. Imagens de vídeo foram tomadas a partir de duas câmeras digitais para atribuir o gait score. Quarenta frangos machos foram aleatoriamente selecionados em condições similares de alojamento e da mesma granja, com idade variando de 49 a 28 dias (dez de cada idade) e usados no experimento. A medida consistiu em induzir a ave a caminhar sobre a plataforma de força que automaticamente registrava o pico de força da passada. O gait score aumentou com o peso e a idade das aves. Foi encontrada assimetria nos picos de força da cada pata, independente da idade ou gait score. Embora não tenha sido identificado visualmente nos frangos, o pico de força vertical é diferente tanto na pata direita quanto na esquerda, levando a um caminhar lento e desigual. A deficiência locomotora foi mais intensa em aves mais velhas.