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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.
显示更多 [+] 显示较少 [-]SEVERITY OF RAMULARIA LEAF SPOT AND SEED COTTON YIELD IN DIFFERENT SOWING TIMES
2016
JOÃO PAULO ASCARI | DEJÂNIA VIEIRA DE ARAÚJO | LEONARDO DIOGO EHLE DIAS | GIOVANI JUNIOR BAGATINI | INÊS ROEDER NOGUEIRA MENDES
The ramularia leaf spot (RLS) disease causes cotton yield losses. Choosing a less susceptible cultivar and a sowing time that are less favorable to the pathogen contribute to the management of this disease. The objective of this work was to evaluate the severity of ramularia leaf spot on cotton cultivars sowed in two different times. The experiment was conducted in a triple factorial design (4x3x2), consisted of four cultivars, the three thirds of the plant and two sowing times, with four replications. Each plot was divided in two twin plots, one with fungicide application (with disease control) and the other without fungicide application (without disease control). The severity assessments were performed every seven days, considering each third of the plant with a diagrammatic scale. Yield was evaluated in each plot. There was a significant interaction between sowing times and the thirds of the plant in the plots without disease control for RLS severity, with the highest values of area under the disease progress curve (AUDPC) in the first sowing time (ST1) and in the lower third of the plant. The FMT705 cultivar had the highest and FM951LL the lowest value of AUDPC. The AUDPC of these cultivars were no statistically different in the second sowing time (ST2), but they had higher AUDPC values in the lower third. Highest yields were found with ST1 in plots with disease control, with no differences between the cultivars, however, lower yields were found in plots without disease control.
显示更多 [+] 显示较少 [-]PERFORMANCE AND QUANTITATIVE AND QUALITATIVE CARCASS TRAITS IN PIGS FED ON CANOLA MEAL
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.
显示更多 [+] 显示较少 [-]DIVERSITY AND GENETIC STRUCTURE OF NATURAL POPULATIONS OF ARAÇÁ (Psidium guineense Sw.)
2016
EDSON FERREIRA DA SILVA | RAFAELA LIMA DE ARAÚJO | CRISTINA DOS SANTOS RIBEIRO MARTINS | LUIZA SUELY SEMEN MARTINS | ELIZABETH ANN VEASEY
Psidium guineense Sw , popularly known as araçá, is a fruit tree there is widely distributed in Brazil and belongs to the Myrtaceae family. In northeastern Brazil, araçá occurs along coast and in the Zona da Mata; its fruit looks like guava but is more acidic and has a stronger smell. There is a little information about this species, which increases the difficulty of conserving its genetic resources and exploiting araçá as an economic resource. The objective of this research was the evaluation of the genetic diversity and genetic structure of P. guineense from Pernambuco’s Zona da Mata. One hundred and fourteen individuals and 18 isozyme loci were evaluated, showing 28 alleles. The percentage of polymorphic loci ( ) and the average number of alleles per locus ( ) were 0.5 and 1.5, respectively, in this population. The expected heterozygosity , which corresponds to the genetic diversity, ranged from 0.22 to 0.23, a high value when considering that isozymes mark access from the functional genome. The differentiation index among the population was ( ) = 0.015; therefore, the populations were not different among the sampled places. The inbreeding values ( ) ranged from - 0.549 to - 0.794, indicating an absence of inbreeding and a greater - than - expected heterozygosity in all the studied populations. The estimated gene flow ( N m ) for a pair of this population ranged from 3.23 to 20.77, sufficient to avoid genetic differentiation among the population and in accordance with the values of genetic divergence found in this study.
显示更多 [+] 显示较少 [-]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.
显示更多 [+] 显示较少 [-]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.
显示更多 [+] 显示较少 [-]NUTRICIONAL ASSESSMENT OF INGREDIENTS USED IN PACIFIC WHITE SHRIMP FEED
2016
CESAR ANTUNES ROCHA NUNES | MARIA DO CARMO MOHAUPT MARQUES LUDKE | CLOVIS MATHEUS PEREIRA | MISLENI RICARTE DE LIMA | JOSÉ DOS SANTOS
Studies on feeding and nutrition of shrimp are still quite scarce; little is known about the use of agribusiness byproducts in shrimp diets. Therefore, this study aimed to perform nutritional and energy assessments of protein-based ingredients for feed of shrimp of the Litopenaeus vannamei species. The design was completely randomized, with six treatments and four replications: a standard diet and five test diets composed of 70% standard diet and 30% test ingredients (poultry viscera flour - PVF, cassava leaf hay - CLH, shrimp head flour - SHF, sugarcane yeast - SCY and castor bean meal - CBM). We used a total of 720 shrimps with mean weight of 8 g each. The parameters of quality showed no significant change by the Tukey’s test (p > 0.05). The apparent digestibility coefficients of PVF, CLH, SHF, SCY and CBM were respectively 27.44, 76.26, 77.78 and 90.10% for dry matter; 76.61, 70.44, 97.67 and 78.29% for protein; and 33.10, 51.19, 90.70 and 78.05% for gross energy. The digestible energy of the ingredients was 1749, 2457, 3914, 3030 and 2130 kcal/ kg; and digestible protein was 42.4, 16.09, 54.62, 23.71 and 14.31%. The SHF reached the highest coefficients of apparent digestibility, crude protein, gross energy and digestible energy. The SCY had the largest apparent digestibility of dry matter. Both SHF and SCY presented improved availability of nutrients and energy for L. vannamei.
显示更多 [+] 显示较少 [-]ANTIFUNGAL POTENTIAL OF EXTRACTS AND FRACTIONS OF Randia nitida LEAVES ON SOYBEAN PATHOGENS AND THEIR PHYTOCHEMISTRY
2016
STHEFANY CAROLINE BEZERRA DA CRUZ-SILVA | ROSEMARY MATIAS | JOSÉ ANTONIO MAIOR BONO | KAREN SILVA SANTO | JULIANE LUDWIG
This study aimed to evaluate the antifungal activity of methanol extract and fractions of leaves of Randia nitida (Kunth) DC on Colletotrichum truncatum (Schw.) Andrus & Moore, Rhizoctonia solani Kühn and Sclerotinia sclerotiorum (Lib.) De Bary and perform chemical and antioxidant activity tests. Crude methanol extract (EBM) and fractions (hexane = FHX, dichloromethane = FDM and ethyl acetate = FAE) underwent classical phytochemical analysis and determination of total phenols, flavonoids and antioxidant activity. Samples were individually incorporated into PDA culture mediums (potato-dextrose-agar) at concentrations of 10, 20, 40, 80 and 160 μg mL - 1 of extract or fraction. Mycelial growth was evaluated when control reached the edge of the plate. Phytochemical results indicated that flavonoids, steroids and triterpenoids are the major chemical constituents in both EBM and fractions. Total phenols, flavonoids and antioxidant activity were higher for FAE and EBM, followed by FDM and FHX; however, the latter showed higher content of steroids and triterpenoids compared to the other fractions. For C. truncatum , R. solani and S. sclerotiorum , the most efficient fractions were respectively FAE, FDM and FHX, all of them in the highest concentration (160 μg mL - 1 ). The highest inhibition rate was observed against S. sclerotiorum , reaching 93.75%. We concluded that all fractions have antifungal activity on the plant pathogens, being FHX the most active against S. sclerotiorum , which might have been due to the presence of steroids and triterpenes.
显示更多 [+] 显示较少 [-]PEDOGENESIS AND SOIL CLASSIFICATION OF AN EXPERIMENTAL FARM IN MOSSORÓ, STATE OF RIO GRANDE DO NORTE, BRAZIL
2016
LUNARA GLEIKA DA SILVA RÊGO | CAROLINA MALALA MARTINS | EULENE FRANCISCO DA SILVA | JÉSSIA JULIANA ALVES DA SILVA | REBECA NAIRONY DA SILVA LIMA
The Rafael Fernandes experimental farm is located in the Alagoinha district, northwest of Mossoró, State of Rio Grande do Norte, Brazil, over two pedogenic formations of different edaphic characteristics, thus needing a more detailed description of its soil types, since this area hosts several experimental fields for researches on agriculture. The objective of this work was to characterize the morphological, physical, chemical and mineralogical features of the most representative soils of this farm, in order to understand its pedogenesis and define its classifications. The whole area was surveyed in order to assess its more representative pedogenic formations. Three soil profiles were classified and described, from which samples were collected in all horizons for physical, chemical and mineralogical analysis. The parent materials and the relief were the determining factors for pedogenic processes of desilication, podzolization and laterization, generating the three main soil types of the area, which were classified up to the 4 th categorical level and described as: Typic Rhodustults (P1), Rhodic Haplustox (P2) and Typic Plinthustalfs (P3).
显示更多 [+] 显示较少 [-]RESIDUAL ACTIVITY OF HERBICIDES APPLIED TO COTTON ON CROPS CULTIVATED IN SUCCESSION
2016
ELIEZER ANTONIO GHENO | RUBEM SILVÉRIO DE OLIVEIRA JUNIOR | JAMIL CONSTANTIN | HUDSON KAGUEYAMA TAKANO | ALEXANDRE GEMELLI
Herbicides with high persistence in soil can cause problems for crops sown in succession to their application. Thus, the aim of this study was to estimate, in greenhouse conditions, the safe period of time after application of preemergent herbicides used on cotton crops (isolated or in mixtures) for the crops grown in succession (bean, corn, and soybean). The experimental design was completely randomized in a factorial scheme (5 x 11) + 1, with five repetitions. For each experiment, treatments combined different time periods between herbicide application and sowing of crops (280, 210, 140, 70, and 0 days before sowing of crops) with eleven herbicide treatments: fomesafen (625 g ha - 1 ) prometryne (1250 g ha - 1 ), diuron (1250 g ha - 1 ), S - metolachlor (768 g ha - 1 ), clomazone (1000 g ha - 1 ), fomesafen + prometryne (625 + 1250 g ha - 1 ), fomesafen + diuron (625 + 1250 g ha - 1 ), fomesafen + S - metolachlor (625 + 768 g ha - 1 ), fomesafen + clomazone (625 + 1000 g ha - 1 ), fomesafen + clomazone + diuron (625 + 1000 + 1250 g ha - 1 ), and fomesafen + clomazone + prometryne (625 + 1000 + 1250 g ha - 1 ), plus an untreated control. Applications of diuron showed the greatest persistence, causing the largest carryover effects for the three crops evaluated. The other treatments showed residual effects or affected crop development when sowings were performed up to 70 days after application. At later periods no significant damage was observed.
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