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TENACITY AND PERSISTENCE OF COPPER FUNGICIDES IN CITRUS SEEDLINGS UNDER SIMULATED RAINFALL
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 [-]QUALITY AND ANTIOXIDANT ACTIVIY OF TOMATO CULTIVATED UNDER DIFFERENT SOURCES AND DOSES OF NITROGEN
2016
JOHN SILVA PORTO | TIYOKO NAIR HOJO REBOUÇAS | MARIA OLIMPIA BATISTA MORAES | MARINÊS PEREIRA BOMFIM | ODAIR LACERDA LEMOS | JOSÉ MAGNO QUEIROZ LUZ
Tomatoes are an important component of the human diet because they are rich in minerals and antioxidants that sequester free radicals in cells, preventing various disorders that affect human health. Here, we aimed to evaluate the effects of different nitrogen sources and concentrations on antioxidant capacity and physical and chemical quality of tomato fruit. The experiment was conducted in Vitória da Conquista, state of Bahia, Brazil, in the experimental field of Universidade Estadual do Sudoeste da Bahia. The experimental setup included a randomized block design with four replicates in a factorial layout of 3 × 3 + 1 (control), for a total of 40 plots. The three treatments comprised different nitrogen sources (calcium nitrate, urea, and ammonium sulfate), applied in three doses (140, 280, and 420 kg ha - 1 ). We evaluated firmness, pH, titratable acidity - TA, soluble solid - SS, SS/TA ratio, ascorbic acid, carotenoids, flavonoids, phenolic compounds and DPPH inhibition, were evaluated after samples were harvested. However, increasing concentrations of N adversely affected the acidity and led to an increase in the SS/TA ratio. Increasing the N concentration also reduced the content of bioactive compounds. excluding carotenoids, which consequently impaired antioxidant activity.
Mostrar más [+] Menos [-]GROWTH, PHYSIOLOGY AND YIELD OF FORMOSA ‘PAPAYA’ CULTIVATED UNDER DIFFERENT DOSES OF COATED AND CONVENTIONAL UREA
2016
GABRIEL BARBOSA DA SILVA JÚNIOR | ÍTALO HERBERT LUCENA CAVALCANTE | EDUARDO MONTEIRO SANTOS | FRANCISCA GISLENE ALBANO | ADRIEL MOURA SILVA
Mineral fertilizer management is one of the most important agronomic techniques applied in papaya cultivation, which generally extracts large amounts of nutrients from soil, especially nitrogen. This study aimed to assess the phytotechnical and physiological attributes and yield of „Formosa‟ papaya hybrid Caliman 01 as a function of different doses of coated and conventional urea in the region of Bom Jesus - PI, Brazil. The treatments were arranged in a factorial scheme (2 × 4) and distributed in a randomized block design with four replications, corresponding to 2 nitrogen sources (coated urea, 43% of N; and conventional urea, 45% of N) and 4 doses nitrogen (350, 440, 530 and 620 g per plant). The N doses used corresponded to 80, 100, 120 and 140% of the nitrogen fertilization. It was used six plants per plot with two row borders, totaling 192 plants cultivated in the field. It was assessed the intercepted photosynthetically active radiation (int.PAR), radiation interception efficiency (PAREff.), leaf area index (LAI), plant height, stem diameter and yield. The coated urea promotes a higher growth and yield of „Formosa‟ papaya compared to the conventional urea. The application of 1.0 g of coated N promotes the production of 2.87 g of fruit per hectare while the application of 1.0 g of conventional N produces only 1.89 g of fruit per hectare, showing that the source of polymerized N increases the use efficiency of N applied to soil.
Mostrar más [+] Menos [-]QUALITY OF MINIMALLY PROCESSED YAM (Dioscorea sp.) STORED AT TWO DIFFERENT TEMPERATURES
2016
ADRIANO DO NASCIMENTO SIMÕES | CLARISSA SOARES FREIRE | EDSON FÁBIO DA SILVA | AURÉLIO PAES BARROS JÚNIOR | SÉRGIO LUIZ FERREIRA-SILVA
This work studied the physical, chemical and bio chemical alterations in minimally processed yam stored at two different temperatures, as well a s the incidence of bacteria of the genus Pseudomonas . The experimental design was completely randomised in a 2x8 factorial design, with two storage temperature s (5 and 10°C) and eight storage times (0, 2, 4, 6, 8, 1 0, 12 and 14 days). Experiments were in triplicate. Yam was selected, peeled and cut into slices of approximate ly 3 cm thickness. The slices were rinsed with wate r, sanitised and then drained in kitchen strainers. Ap proximately 300 g of the processed product were pac ked in nylon multilayers 15 μ m thick, 15 cm wide and 20 cm long. The packs were sealed, weighed and kept at 5 and 10 ± 2°C for 14 days. Fresh weight loss, baking tim e, enzymatic activity of polyphenol oxidases, perox idases and catalases, total soluble phenol content, and an tioxidant capacity were evaluated, as well as visua l analysis and incidence of Pseudomonas sp. Means of temperatures were compared by Tukey ́s test at 5% significance. Yam storage at 5°C reduced weight loss and kept vis ual quality for longer; it also reduced cooking tim e and the activity of the enzymes polyphenol oxidase and pero xidase. In contrast, it promoted higher content of total soluble phenols, as well as a higher catalase activ ity and antioxidant capacity. During the storage ti me, there was no incidence of Pseudomonas sp. Minimally processed yam stored at 10°C may be sold for up to six days, and yam stored at 5ºC for up to 14 days.
Mostrar más [+] Menos [-]SYMBIOTIC EFFICIENCY OF RHIZOBIA STRAINS WITH COWPEA IN SOUTHERN MARANHÃO
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 [-]AGRONOMIC EFFICIENCY OF THE INTERCROPPING OF ARUGULA WITH CARROT UNDER DIFFERENT POPULATION COMBINATIONS
2016
THAÍZA MABELLE DE VASCONCELOS BATISTA | FRANCISCO BEZERRA NETO | ÍTALO NUNES SILVA | MAIELE LEANDRO DA SILVA | ELIANE QUEIROGA DE OLIVEIRA | AURÉLIO PAES BARROS JÚNIOR
The objective of this study was to evaluate the agronomic efficiency of intercropping combinations of carrot and arugula at different population densities in bicropping in the semi - arid conditions of the Brazilian Northeast. The study was conducted at the "Rafael Fernandes" Experimental Farm of the Universidade Federal Rural do Semi - Árido (UFERSA) during the period September 2011 to February 2012. The experimental design was of randomized complete blocks with treatments arranged in a 4 x 4 factorial scheme with four replications. The combinations were four population densities of carrot (40, 60, 80 and 100% of the recommended population in sole crop – RPSC) with four population densities of arugula (40, 60, 80 and 100% of the RPSC). The recommended population densities for sole crops of carrot and arugula are 500,000 and 1,000,000 plants per hectare, respectively. All treatments were fertilized with hairy woodrose ( Merremia aegyptia L.), a spontaneous species of the Caatinga biome. The highest agronomic efficiency of carrot intercropped with arugula in bicropping was achieved in the combination of 40% of RPSC for the carrot and 100% of RPSC for the arugula. The commercial maximum yield (33.74 t ha - 1 ) of carrot roots and the maximum yields of arugula green mass (8.06 and 2.67 t ha - 1 ) in both cultivations were also obtained in the combination of population densities of 40% of RPSC for carrot and 100% of RPSC for arugula.
Mostrar más [+] Menos [-]PHYSIOLOGICAL AND SANITARY QUALITY OF DESICCATED AND STORED AZUKI BEAN SEEDS
2016
CÁSSIO JARDIM TAVARES | PATRÍCIA CARDOSO FERREIRA | ADRIANO JAKELAITIS | JULIANA DE FÁTIMA SALES | OSVALDO RESENDE
The objective of this research was to evaluate the effects of using different herbicides as desiccants in pre - harvest and the effects of storage on the physiological and sanitary quality of azuki bean seeds ( Vigna angularis Willd). The experiment was arranged in a randomized complete block design in a split plot scheme, with four replications. Four herbicides were tested: paraquat (400 g a.i. ha - 1 ), glufosinate ammonium (400 g a.i. ha - 1 ), glyphosate (720 g a.i. ha - 1 ), flumioxazin (30 g a.i. ha - 1 ) and a control without herbicide application. In the subplots seed quality was tested in two evaluation periods: at harvest and six months after harvest. Desiccant was applied when the azuki beans were physiologically mature. We assessed the physiological and sanitary quality of the seeds using a vigour and seed health test. The use of glyphosate resulted in a higher incidence of abnormal seedlings and reduced size and weight of the seedlings. With paraquat and flumioxazin the physiological quality was maintained and there was reduced pathogen infestation in the seeds six months after harvest. Storage affected the physiological quality of the azuki bean seeds.
Mostrar más [+] Menos [-]CHAMOMILE PRODUCTION USING SUPPLEMENTARY IRRIGATION AND ORGANIC FERTILIZATION IN SANDY SOILS
2016
CATARINY CABRAL ALEMAN | PATRICIA ANGÉLICA ALVES MARQUES | ANA CLAUDIA PACHECO
The use of medicinal plants in the herbal medicine of Brazilian Health System has intensified production and the need for developing efficient agricultural techniques that promote greater productivity of these species. The objective of this work was to evaluate the chamomile production at field conditions as a function of irrigation depths and organic fertilizer rates. The experiment was conducted in the Universidade do Oeste Paulista (Campus II experimental area), in Presidente Prudente, São Paulo State, Brazil. A triple factorial experimental design was used, consisting of irrigation rates (150, 100, 75, 50, 25 and 0% of the reference evapotranspiration - ETo), organic manure types (poultry and cattle manure) and manure rates (0, 3 and 5 kg m-2), with four replications. The capitula production per plant, capitula dry weight and yield per water input (water use efficiency) were evaluated. The supplementary irrigation combined with organic manure fertilization provided the highest capitula yield for chamomile crop in the Presidente Prudente region. The combination of poultry manure at rate of 5 kg m-2 with water depth equal to 150% of the ETo resulted in higher average values of capitula fresh and dry weight and water use efficiency.
Mostrar más [+] Menos [-]IMPACT OF SALINE CONDITIONS AND NITROGEN FERTILIZATION ON CITRUS PRODUCTION AND GAS EXCHANGES
2016
JÔNATAS RAULINO MARQUES DE SOUSA | HANS RAJ GHEYI | MARCOS ERIC BARBOSA BRITO | DIEGO AZEVEDO XAVIER | GUILHERME DE FREITAS FURTADO
In two simultaneous experiments, we evaluated the impact of brackish irrigation water and nitrogen (N) fertilization on the production of citrus (scion-rootstock combinations) and its associated gas exchanges. These experiments were conducted at the Campus of Federal University of Campina Grande, Brazil in a protected environment (shade screens on the sides) using drainage lysimeters. Experiment I used a randomized block design (3 replicates), in a 5 × 3 factorial arrangement, corresponding to five water salinity levels (0.6, 1.2, 1.8, 2.4, and 3.0 dS m-1) and three scion-rootstock combinations: RS1– Common Sunki mandarin (TSKC) × Poncirus trifoliata English (TRENG) - 256; RS2– Common Rangpur lime (LCRSTC); and RS3– TSKC × (Rangpur lime (LCR) × P. trifoliata (TR)) - 059; with Mimo do Céu orange as the scion variety. Experiment II used a randomized block design (3 replicates), in a 3 × 2 factorial arrangement, corresponding to the three scion/rootstock combinations and two nitrogen (N) doses (100 and 200 mg kg-1 of soil). Plants were irrigated with water of 3.0 dS m-1. For both experiments, gas exchanges and mean mass of fruits were evaluated at harvest. Gas exchanges were inhibited in plants under saline stress. Plants grafted with Common Rangpur lime showed greater production potential than did the other genotypes studied, even under brackish water conditions.
Mostrar más [+] Menos [-]NUTRITIVE VALUE OF DIETS WITH INACTIVE DRY YEAST FOR SAANEN GOATS IN THE PERIPARTUM PERIOD
2016
BRUNA SUSAN DE LABIO MOLINA | LARISSA RIBAS DE LIMA | LUDMILA COUTO GOMES | LUCIANO SOARES DE LIMA | CLAUDETE REGINA ALCALDE
The aim was to evaluate the replacement of soybean meal by inactive dry yeast ( Saccharomyces cerevisiae ) from sugar cane on nutritive value of diets for Saanen goats in the peripartum. Twenty - four Saanen goats (nine primiparous, 55.35 ± 4.55 kg and fifteen multiparous, 73.12 ± 8.51 kg) in prepartum and postpartum periods were distributed in a completely randomized design with a 3 × 2 (diet × parturition order) factorial arrangement. Diets were composed of soybean meal, soybean meal plus dry yeast or dry yeast as protein source, and other ingredients: ground corn, mineral supplement and limestone. The roughage source used was the whole plant corn silage (40% of the total diet). Diets were evaluated as dry matter intake and digestibility of nutrients. The diet with total dry yeast inclusion promoted a reduction on the ether extract intake (postpartum) and ether extract digestibility (prepartum and postpartum), due its lower ether extract content when compared to the other diets. Multiparous goats presented higher intakes for dry matter, nutrients and total digestible nutrients in both evaluated periods due their higher intake capacity. Primiparous goats in postpartum had better coefficients of digestibility for dry matter, organic matter, crude protein and total carbohydrates, and so a higher energetic value, attributed to total digestible nutrients compared to multiparous ones. Dry yeast can replace soybean meal with no changes on nutritive value of diets for Saanen goats.
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