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TENACITY AND PERSISTENCE OF COPPER FUNGICIDES IN CITRUS SEEDLINGS UNDER SIMULATED RAINFALL Texto completo
2016
ANTONIO EDUARDO FONSECA | BRUNO DE MORAES NUNES | JOÃO BATISTA FERREIRA JÚNIOR
The amount of fungicide that adheres to the leaf during spraying and the amount that remain on the leaf after weathering are the main factors that defines the amount of active residue on the leaf surface to effectively control plant pathogens. Thus, the objective of this work was to evaluate the tenacity and persistence of copper in citrus seedling leaves under simulated rainfall in Jaboticabal, State of São Paulo, Brazil. The evaluated variables were copper content, solution retention, surface tension and drop spectrum. A significant and inversely proportional linear relationship to drops <100 μm was found. The percentage of copper retained in leaves of citrus seedlings with copper fungicides of suspension concentrate (SC) formulations after simulated rainfall was greater than 80%. Copper fungicides of SC formulations presented the lowest surface tension, allowing greater tenacity and persistence of copper on seedlings of citrus leaves after simulated rainfall and increased contact between the drops and leaf surface.
Mostrar más [+] Menos [-]PRODUCTION COMPONENTS OF Vigna unguiculata (L. Walp) IRRIGATED WITH BRACKISH WATER UNDER DIFFERENT LEACHING FRACTIONS Texto completo
2016
JOSÉ FRANCISCO DE CARVALHO | ÊNIO FARIAS DE FRANÇA E SILVA | GERÔNIMO FERREIRA DA SILVA | MÁRIO MONTEIRO ROLIM | ELVIRA MARIA REGIS PEDROSA
The objective of this work was to evaluate the production components of cowpea ( Vigna unguiculata L. Walp) subjected to irrigation with brackish water and different leaching fractions. The experiment was conducted in a lysimeter system of the Department of Agricultural Engineering of the Federal Rural University of Pernambuco, Recife campus. The treatments, consisting of two water salinity levels (ECw) (1.2 and 3.3 dS m - 1 ) and five leaching fractions (0, 5, 10, 15 and 20%), were evaluated using a completely randomized design in a 2x5 factorial arrangement with four replications. The variables evaluated were: number of pods per plant, 100 - grain weight, number of grains per pod, grain and shoot dry weight, grain yield and harvest index. The soil salinity increased with increasing salinity of the water used for irrigation, and reduced with increasing leaching fraction. The salinity of the water used for irrigation influenced only the variables number of pods per plant and grain yield. The estimated leaching fractions of 9.1% and 9.6% inhibited the damage caused by salinity on the number of pods per plant and grain yield, respectively. Therefore, the production of V. unguiculata irrigated with brackish water, leaching salts from the plant root environment, is possible under the conditions evaluated.
Mostrar más [+] Menos [-]GENETIC DIVERSITY IN ACCESSIONS OF Stylosanthes spp. USING MORPHOAGRONOMIC DESCRIPTORS Texto completo
2016
RONALDO SIMÃO DE OLIVEIRA | MANOEL ABÍLIO DE QUEIRÓZ | ROBERTO LISBOA ROMÃO | GRÉCIA CAVALCANTI DA SILVA | BRUNO PORTELA BRASILEIRO
The great diversity of plants in the Brazilian Semiarid environment represents a vital natural resource for the human populations of these areas. Many of these plants have been subject to extractivism and among these, the species of the genus Stylosanthes , which have occurrence in this region, show great potential, however, studies on this topic are limited, and little is known about the existing variability among these plants. Therefore, further study is necessary, to facilitate the development of cultivars. This might reduce the scarcity of fodder supply in this region, but to commence a plant breeding programme, it is essential to identify genetic variability. Therefore, this study evaluated 25 accessions of Stylosanthes spp., to identify the most suitable candidates to be parents in a plant breeding programme for the semiarid region of the state of Bahia. Two experiments were carried out in different sites in an experimental design of randomized blocks with four replicates, with a spacing of 3.0 × 8.0 m. A large amount of genetic diversity was observed among accessions and the genotypes BGF 08 - 007, BGF 08 - 016, BGF 08 - 015 and BGF 08 - 021 were the most divergent in the overall evaluation. For the structuring of segregating populations, it is recommended to combine the genotypes BGF 08 - 016, BGF 08 - 015, BGF 08 - 007 and BGF 08 - 006, and for the interspecific crosses, a hybrid from the accession BGF - 024 with the accessions BGF 08 - 016 or BGF 08 - 015. This might generate superior individuals for mass descriptors, which are the most important for animal forage breeding.
Mostrar más [+] Menos [-]MODELING OF FUEL CONSUMPTION FOR FOREST TRANSPORTATION Texto completo
2016
POMPEU PAES GUIMARÃES | JULIO EDUARDO ARCE | EDUARDO DA SILVA LOPES | ALLAN LIBANIO PELISSARI | GABRIELA SALAMI | VINICIUS GOMES DE CASTRO
As fuel costs increase, it is essential to take measures involving planning and control on any activities with high consumption. Thus, the main aim of this work was modeling the fuel consumption of forest road transportation by truck. We collected data about time, driving distance, average speed, fuel consumption and the load carried by the vehicle for loaded trips, unloaded trips, and the total cycle of forest transport in regions between the municipality of Campo do Tenente (forest site) and Piên (factory) located in Paraná state, Brazil. The Pearson’s correlation was used to determine the relationship between variables, while the Stepwise procedure was used to generate regression equations to estimate fuel consumption. The highest correlations were found between fuel consumption and driving distance, average speed and liquid weight of the load; also, there was a significant correlation between driving distance and average speed. Adjusted equations were statistically adequate to estimate fuel consumption based on driving distance, liquid weight of the load, average speed and duration time for loaded trips, unloaded trips and the total forest road transportation cycle.
Mostrar más [+] Menos [-]PERFORMANCE AND QUANTITATIVE AND QUALITATIVE CARCASS TRAITS IN PIGS FED ON CANOLA MEAL Texto completo
2016
LINA MARÍA PEÑUELA SIERRA | IVAN MOREIRA | PAULO LEVI DE OLIVEIRA CARVALHO | ADRIANA GOMEZ GALLEGO | LAURA MARCELA DIAZ HUEPA | CLODOALDO DE LIMA COSTA FILHO
Two experiments were performed for the purpose of determining the nutritional value and assess the performance and carcass traits in pigs fed on canola meal (Brassica napus). Experiment I consisted of a total digestibility trial conducted with 14 castrated commercial crossbred male pigs with 60.69 ± 4.26 kg initial live weight. The treatments consisted of a control diet based on maize and soybean meal and another diet containing canola meal (control + 25% canola meal). Each pig was an experimental unit, totalling seven experimental units per diet. The digestible energy and the metabolizable energy of canola meal used was 2,999 and 2,730 kcal.kg-1, respectively. These values were used to formulate the diets of the performance experiment. Experiment II included 50 crossbred pigs with an average initial live weight of 29.90 ± 1.16 kg and an average final live weight of 60.33 ± 3.38 kg during the growing phase, and an average initial live weight of 60.37 ± 1.6 kg and an average final live weight of 90.37 ± 3.19 kg during the finishing phase. The experimental design consisted of randomized blocks, with four treatments (6, 12, 18, and 24% canola meal), 10 repetitions, and one pig per experimental unit. The control diet was formulated with 0% canola meal. The data were assessed using ANOVA test and the averages of the treatments were compared using Dunnett's test and regression analysis at a 5% probability level. The results suggest that it is possible to use up to 24% canola meal in the diets for pigs during the growing and finishing phases without affecting the performance and carcass traits.
Mostrar más [+] Menos [-]SYMBIOTIC EFFICIENCY OF RHIZOBIA STRAINS WITH COWPEA IN SOUTHERN MARANHÃO Texto completo
2016
THIAGO PALHARES FARIAS | BRUNO LIMA SOARES | ANA REGIA ALVES DE ARAÚJO | FATIMA MARIA DE SOUZA MOREIRA
The objective of this study was to evaluate the symbiotic efficiency of three novel nitrogen-fixing bacterial strains with cowpea cv. BRS Guariba as forage. Two experiments were carried out in the field in Balsas and São Raimundo das Mangabeiras, MA, in a randomized block design with seven treatments and four replications: three novel strains efficient in symbiotic nitrogen fixation with cowpea (UFLA 3-153, UFLA 3-154 and UFLA 3-164), two strains already approved as inoculants by MAPA (UFLA 3-84/SEMIA 6461 and INPA 3-11B/SEMIA 6462), and two controls without inoculation, with and without mineral N. Symbiotic efficiency of strains was determined by the number of nodules, nodules dry matter, shoot dry matter, relative efficiency, crude protein content and shoot N content. Strains UFLA 3-154 and UFLA 3-164 were the most efficient in Balsas, whereas UFLA 3-153 and UFLA 3-164 were the most efficient in São Raimundo das Mangabeiras. Strains UFLA 3-153, UFLA 3-154 and UFLA 3-164 were more efficient in symbiotic nitrogen fixation with cowpea than the strains already approved as inoculants UFLA 3-84 and INPA 3-11B in the climatic and edaphic conditions of southern Maranhão. UFLA 3-164 is the most efficient strain in this region.
Mostrar más [+] Menos [-]INSECT DIVERSITY IN AN EXPERIMENTAL VINEYARD IN THE STATE OF RIO GRANDE DO NORTE, BRAZIL Texto completo
2016
JEFFERSON BRUNO CARVALHO SOARES | EWERTON MARINHO COSTA | FRANCISCO EDIVINO LOPES DA SILVA | ELTON LUCIO ARAUJO
The objective of this work was to survey the entomofauna in an experimental vineyard ( Vitis spp.) in the semiarid of the State of Rio Grande do Norte (RN), Brazil. The survey was conducted from November 2012 to January 2013 at the Rafael Fernandes experimental farm of the Universidade Federal Rural do Semi - Árido (UFERSA), Mossoró, RN, in an area of 2,500 m 2 , cultivated with the Italia , Niagara Rosada and Isabel grapevine varieties. The insect collection was performed weekly during the grapevine flowering and fruiting periods, through a passive method, using four Pitfall traps, and an active method, collecting insects from the tree canopies (branches, leaves, flowers and fruits) using entomological net, tweezers and brushes. In the passive collection, 1,598 insects from five orders and 25 families were collected, especially from the Formicidae (83%), Dolichopodidae (5.9%) and Cicadellidae (1.9%) families, which were the most abundant. In the active collection, 288 insects from five orders and 14 families were collected, especially from the Vespidae (160 specimens) and Apidae (78 specimens) families, which were the most abundant, representing 82.7% of the total collected insects. The greater diversity (13 families) and greater number of insects collected (186 specimens) were observed in the grapevine variety Isabel.
Mostrar más [+] Menos [-]EFFECT OF NITROGEN-FIXING BACTERIA ON GRAIN YIELD AND DEVELOPMENT OF FLOODED IRRIGATED RICE Texto completo
2016
AMAURI NELSON BEUTLER | GIOVANE MATIAS BURG | EVANDRO ADEMIR DEAK | MARCELO RAUL SCHMIDT | LEANDRO GALON
This study aimed at evaluating the effect of Azospirillum brasilense , a nitrogen - fixing bacterium, on flooded irrigated rice yield. Evaluations were carried out in a shaded nursery, with seedlings grown on an Alfisol. Were performed two sets of experiments. In the first, were carried out four experiments using the flooded rice cultivars INIA Olimar, Puitá Inta - CL, Br Irga 409 and Irga 424; these trials were set up as completely randomized design in a 5x4 factorial scheme, with four replications. Treatments consisted of five nitrogen rates (0, 40, 80, 120 and 160 kg ha - 1 ) and four levels of liquid inoculant Ab - V5 and Ab - V6 - A. brasilense (0, 1, 2 and 4 times the manufacturer's recommendation) without seed treatment. In second set, were performed two experiments using the cultivars Puitá Inta - CL and Br Irga 409, arranged in the same design, but using a 4x2 factorial. In this set, treatments were composed of four levels of Ab - V5 and Ab - V6 - A. brasilense liquid inoculant (0, 1, 2 and 4 times the recommendation of 100 mL ha - 1 ), using rice seeds with and without insecticide and fungicide treatment. Shoot dry matter, number of panicles, and rice grain yield per pot were the assessed variables. The results showed that rice seed inoculation with A. brasilense had no effects on rice grain yield of the cultivars INIA Olimar, Puitá Inta - CL, Br Irga 409 and Irga 424.
Mostrar más [+] Menos [-]EMPIRICAL MODELS FOR PERFORMANCE OF DRIPPERS APPLYING CASHEW NUT PROCESSING WASTEWATER Texto completo
2016
KETSON BRUNO DA SILVA | RAFAEL OLIVEIRA BATISTA | FRANCISCO DE OLIVEIRA MESQUITA | DANIELA DA COSTA LEITE COELHO | WESLEY DE OLIVEIRA SANTOS
The objective of this work was to develop empirical models for hydraulic performance of drippers operating with cashew nut processing wastewater depending on operating time, operating pressure and effluent quality. The experiment consisted of two factors, types of drippers (D1=1.65 L h-1, D2=2.00 L h-1 and D3=4.00 L h-1), and operating pressures (70, 140, 210 and 280 kPa), with three replications. The flow variation coefficient (FVC), distribution uniformity coefficient (DUC) and the physicochemical and biological characteristics of the effluent were evaluated every 20 hours until complete 160 hours of operation. Data were interpreted through simple and multiple linear stepwise regression models. The regression models that fitted to the FVC and DUC as a function of operating time were square root, linear and quadratic, with 17%, 17% and 8%, and 17%, 17% and 0%, respectively. The regression models that fitted to the FVC and DUC as a function of operating pressures were square root, linear and quadratic, with 11%, 22% and 0% and the 0%, 22% and 11%, respectively. Multiple linear regressions showed that the dissolved solids content is the main wastewater characteristic that interfere in the FVC and DUC values of the drip units D1 (1.65 L h-1) and D3 (4.00 L h-1), operating at work pressure of 70 kPa (P1).
Mostrar más [+] Menos [-]INOCULATION OF DIAZOTROPHIC BACTERIA AND NITROGEN FERTILIZATION IN TOPDRESSING IN IRRIGATED CORN Texto completo
2016
VANESSA ZIRONDI LONGHINI | WÉSLEY CARLOS ROSSINI DE SOUZA | MARCELO ANDREOTTI | NATALIA DE ÁVILA SOARES | NÍDIA RAQUEL COSTA
Corn is a nitrogen-intensive crop, and the use of management practices such as inoculation of the seed with diazotrophic bacteria, which can maximize crop productivity and reduce the need of nitrogen fertilizers, may result in lower production costs. The present study aimed to evaluate the effect of inoculation of corn seed with Azospirillum brasilense and controlled addition of nitrogen to topdressing on the nutrition, production components, and productivity of crop grain. The experimental design was a randomized block design, with four replications in a 2 × 5 factorial scheme. The treatments consisted of inoculation or not of corn seed with A. brasilense (at 100 mL per 25 kg of seed) and five nitrogen (N) levels in topdressing (0, 30, 60, 90, and 120 kg N ha-1 from urea [45% N]) were applied when the corn was in the phenological growth stage V6. Foliar macronutrients, foliar chlorophyll index (FCI), production components, and yield of corn grain were valuated. Inoculation of corn seeds with A. brasilense increased plant height and grain yield. Fertilization in topdressing, with N levels up to 120 kg ha-1, linearly increased the foliar nutrients and productivity of corn cultivated in the spring/summer in the low-altitude Cerrado region of Brazil.
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