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CONTAMINATION POTENTIAL OF SPECIFIC IONS IN SOIL TREATED WITH REJECT BRINE FROM DESALINATION PLANTS
2016
ANDLER MILTON PAIVA DE OLIVEIRA | CEZAR AUGUSTO MEDEIROS REBOUÇAS | NILDO DA SILVA DIAS | JEANE CRUZ PORTELA | ADRIANA ARAÚJO DINIZ
Percolation columns constructed in the Laboratory can predict the degree of contamination in soil due to reject brine disposal and can be a tool for reducing environmental impacts. This study aim to evaluate the mobilization of ions in reject brine from desalination process by reverse osmosis. The mobilization of the contaminant ions in the saline waste was studied in glass percolation columns, which were filled with soil of contrasting textures (eutrophic CAMBISOL, typic dystrophic Red OXISOL, ENTISOL Quartzipsamment). Experiments ware repeated three times each, and the initial and final concentrations of the ion contaminants were analyzed. The pollution potential of this wastewater was determined by the retardation factor and dispersion-diffusion coefficient of K+, Cl- and Na+ for each studied soil. The differences in the displacement curves of the ions present in the saline waste among various soil types were analyzed. The Entisol Quartzipsamment showed a higher forward speed of the ions K+ and Cl- (greater retardation factor, i.e., greater power of the subsurface contamination for these ions). In typic dystrophic Red OXISOL, the ions move with greater ease and therefore produced greater groundwater contamination. In eutrophic CAMBISOL, the low coefficient of diffusion-dispersion in all ions was evaluated (i.e., reduced ion mobility is directly influenced by their exchangeable levels).
Mostrar más [+] Menos [-]INSETICIDAL OILS FROM AMAZON PLANTS IN CONTROL OF FALL ARMYWORM
2016
ANA CLÁUDIA VIEIRA DOS SANTOS | CARROMBERTH CARIOCA FERNANDES | LUCAS MARTINS LOPES | ADALBERTO HIPÓLITO DE SOUSA
The potential insecticidal of oils from southwestern Amazon plants against Spodoptera frugiperda (J. E. Smith, 1797) (Lepidoptera: Noctuidae) was investigated. Initial bioassays were performed with undiluted oils from 11 plant species. The efficacy of the oils was evaluated against eggs and third-instar caterpillars of S. frugiperda. The oils of Copaifera sp. (Leguminosae), Orbignya phalerata (Arecaceae), and Carapa guianensis (Meliaceae) displayed a high efficacy against the caterpillars and were used in subsequent concentration-response bioassays, at concentrations established through preliminary tests. The highest nonlethal concentrations of oils and the lowest lethal concentrations were calculated. A completely randomized design was adopted in both bioassays. The LC50 of the oils varied from 7.50 to 60.84% (v/v). Copaifera sp. oil had the highest toxicity and was 6.84-fold more toxic than O. phalerata oil and 8.11-fold more toxic than Carapa guianensis oil. In general, oils from Copaifera sp., O. phalerata, and Carapa guianensis were effective in controlling S. frugiperda caterpillars under laboratory conditions, and are good candidates for use in integrated management programs of corn pests.
Mostrar más [+] Menos [-]WINTER BEAN PRODUCTIVITY UNDER UROCHLOA STRAW FERTILIZED WITH NITROGEN
2016
NÍDIA RAQUEL COSTA | MARCELO ANDREOTTI | KENY SAMEJIMA MASCARENHAS LOPES | KAZUO LEONARDO ALMEIDA YOKOBATAKE | CÉSAR GUSTAVO DA ROCHA LIMA
An experiment was conducted during the years 2009 and 2010 to evaluate the effects of Urochloa forage straw and nitrogen fertilization on soil properties, nutritional foliar content, index of foliar chlorophyll (IFC) values, production components, and grains yields of winter bean ( Phaseolus vulgaris ‘Pérola’) in the Cerrado lowlands region of Brazil. The treatments consisted of planting bean crops under straw of Urochloa brizantha ‘Xaraés’ and Urochloa ruziziensis, fertilized with urea - sourced N (0, 50, 100, 150, and 200 kg N ha - 1 ). The experimental design was randomized blocks with four replications, and a factorial scheme of 2 × 5. The greater yield of U. brizantha dry matter in the two years of evaluation increased bean leaf nutrient levels. The nutritional increase with increasing N application rates showed that the straw produced by the forages had a positive effect on bean nutrition. The grain yield was satisfactory but was not affected by the forage species nor by changes in the N application rates. The Urochloa straw increased the soil organic matter (SOM), Ca, and Mg content in both evaluated years, affected the decomposition and mineralization of organic residues, and ensured the proper development of the bean plants.
Mostrar más [+] Menos [-]COLD TOLERANCE OF BANANA FRUITS OF DIFFERENT CULTIVARS
2016
JOÃO ALISON ALVES OLIVEIR | LUIZ CARLOS CHAMHUM SALOMÃ | DALMO LOPES DE SIQUEIR | PAULO ROBERTO CECON
The objective of this work was to evaluate the tolerance of fruits of different banana cultivars to low temperature storages. Fruits of the cultivars Nanicão (AAA), Prata (AAB), Vitória (AAAB), Maçã (AAB) and Caipira (AAA) were used. Clusters of three fruits were kept in cold storage for 7, 14 and 21 days, with average temperature of 10.53±0.37°C and relative humidity of 85%. Subsequently, the clusters were transferred to temperatures of 22±0.39°C and evaluated for 16 days. The fruits of all cultivars remained green after 21 days of storage at 10.53±0.37°C. Fruits of the cultivar Nanicão did not completely ripened after transferred to the 22°C storage, when stored for 7 days at low temperature. These fruits were firmer, with green peel and low soluble solids and titratable acidity. The fruits of all cultivars complete the ripening when transferred to room temperature after 21 days of cold storage. Chilling injuries increased with cold storage time in all cultivars. The cultivars Nanicão, Caipira and Maçã had more symptoms of chilling injury, while Prata and Vitória were more tolerant to the cold storage (10.53°C) for up to 21 days, showing normal ripening after transferred to the 22±0.39°C storage.
Mostrar más [+] Menos [-]IRRIGATION WITH SALINE WATER AND NITROGEN IN PRODUCTION COMPONENTS AND YIELD OF SUNFLOWER
2016
JOÃO BATISTA DOS SANTOS | DOROTEU HONÓRIO GUEDES FILHO | HANS RAJ GHEYI | GEOVANI SOARES DE LIMA | LOURIVAL FERREIRA CAVALCANTE
Due to the quantitative and qualitative limitation of water resources, saline water irrigation and nitrogen (N) fertilisation can contribute positively to the expansion of sunflower cultivation in the semiarid region of Northeast Brazil. Thus, this study aimed to evaluate production components and yield of sunflower, cv. „Embrapa 122 - V2000‟, irrigated with waters of different salinity levels (electrical conductivity – ECw) and fertilised with varying amounts of N in a field experiment in an eutrophic Quartzarenic Neosol from November 2012 to February 2013. The experiment was performed in a completely randomised block design in split plots, in a 5 x 4 factorial scheme, which corresponded to five ECw levels (0.15, 1.5, 2.5, 3.5 and 4.5 dS m - 1 ) and four N levels (60, 80, 100 and 120 kg ha - 1 ), with three replicates and 30 plants per plot. The interaction between water salinity levels and N did not have significant effects on the studied variables; irrigation water salinity had isolated negative effects on the total number of achenes, number of viable achenes, productivity and oil yield of achenes. The increase in N levels stimulated the total number and the number of viable achenes, the mass of 1,000 achenes, capitulum diameter and productivity of achenes of sunflower, cv. „Embrapa 122 - V2000‟, but had no effect on the oil content of achenes. N levels of up to 100 kg ha - 1 promoted adequate oil content in the achenes of sunflower, cv „Embrapa 122 - V2000‟.
Mostrar más [+] Menos [-]METHODS FOR OVERCOMING SEED DORMANCY AND THE INITIAL GROWTH OF Ziziphus joazeiro Mart. IN DIFFERENT SOILS
2016
JOSENARA DAIANE DE SOUZA COSTA | JOSÉ ALIÇANDRO BEZERRA DA SILVA | DANIELA SIQUEIRA COELHO | ÍTALO EMANUEL DOS ANJOS SANTOS | TALES XAVIER SEABRA
Considering the potential and importance of biodiversity of the Caatinga biome, studies on endemic species are relevant to conservation of its natural resources. The objectives of this work was to evaluate seed viability and physical methods for overcoming seed dormancy in juazeiro (Ziziphus joazeiro Mart.) and assess the influence of different types of soil on the initial growth of juazeiro plants. The experiments were conducted in three stages. In the first stage, the viability of seeds from different lots was evaluated using the tetrazolium test. The second stage was conducted in a plant nursery, evaluating the application of physical processes (scarification with sandpaper and hammer) in overcoming seed dormancy, and the initial growth of the plants. In the third step, the chlorophyll a and b contents, gas exchange and dry matter accumulation were evaluated in young juazeiro plants in three types of soil (Oxisol, Entisol and Vertisol). The results indicate that the viability of juazeiro seeds is greatly influenced by differences between the progenitor plants and by storage conditions, which enable a longevity of two years when stored at 22°C and 16% of relative humidity. The scarification methods with sandpaper and hammer are not efficient to reduce the time and uniform seed germination. The juazeiro plants have high growth potential in different edaphic environments, adapting well to soils of different textures and chemical compositions.
Mostrar más [+] Menos [-]IRRIGATION DEFICIT STRATEGIES ON PHYSIOLOGICAL AND PRODUCTIVE PARAMETERS OF 'TOMMY ATKINS' MANGO
2016
MARCELO ROCHA DOS SANTOS | SÉRGIO LUIZ RODRIGUES DONATO | EUGÊNIO FERREIRA COELHO | PAULO ROBERTO FERNANDES COTRIM JUNIOR | IGOR NOGUEIRA DE CASTRO
The objective of this work was to evaluate the gas exchange, leaf temperature, yield and water use efficiency in 'Tommy Atkins' mango under irrigation deficit strategies. The experimental design was randomized block, with seven treatments with regulated deficit irrigation (RDI) under micro - spray and five treatments with partial root - zone drying (PRD) under drip irrigation. The treatments on RDI consisted of application of 100, 75 and 50% of ETc at the stages S1 (beginning of flowering to fruit set) S2 (fruit development) and S3 (fruit physiological maturation). The treatments on PRD consisted of application of 100, 80, 60 and 40% of ETc, in the same three stages, alternating the irrigation side every 15 days. The regulated deficit irrigation causes less negative interference in gas exchange than the partial root - zone drying, and the climate factors affect the gas exchange and leaf temperature of 'Tommy Atkins' mango more than the regulated deficit irrigation. The partial root - zone drying irrigation with 60 and 40% of ETc causes a decrease in the 'Tommy Atkins' mango yield. The regulated deficit irrigation up to 50% of ETc, applied at the fruit maturation stage, maintain the yield and water use efficiency.
Mostrar más [+] Menos [-]EFFECT OF PARTICLE SIZE AND BACTERIAL INOCULANT ON THE TEMPERATURE, DENSITY AND pH OF PEARL MILLET SILAGES
2016
ANÍBAL COUTINHO DO RÊGO | GUSTAVO REZENDE SIQUEIRA | GERALDO BENEDITO DE SOUZA ALMEIDA | RICARDO DIAS SIGNORETTI | FLÁVIO DUTRA DE RESENDE
The present study aimed to investigate the temperature at different depths of the stack silo and strata front profile before and after the removal of silage. Also, the pH values in the upper and lower profile and the silage density of the fresh materials (FM) and dry matter (DM) in pearl millet silages with particle sizes of 5 or 20 mm, with or without inoculant, were assessed, using corn silage as controls. There was an interaction (P<0.05) silage × stratum profile and silage × depth profile for the temperatures before the removal of silage, and the pearl millet silages had lower temperatures in the upper stratum compared to corn. The temperature gradient between the silage and environment pearl millet and corn silos were smaller in the lower stratum profile. The temperature gradient after the removal of the silage was less than 50 cm deep at all the pearl millet silos. There were no differences in the densities of the FM and DM of the studied silages. The pH values of the silages before their removal were higher in the upper stratum and lower stratum in the bottom of all the pearl millet silages, in contrast with corn silage. The pearl millet silos had lower pH values in the lower stratum of the silo. Silages with 5 mm particle size provide lower temperatures in the middle portion of the panel before the removal of the silage. The use of bacterial inoculant in this study did not change the characteristics evaluated.
Mostrar más [+] Menos [-]FLUXAPYROXAD IN THE ASIAN SOYBEAN RUST CONTROL IN THE CERRADO BIOME
2016
RAFAEL MENEZES SILVA DE FREITAS | LEONEL ESPÓSITO DE LIMA | ROGER SANTOS SILVA | HERCULES DINIZ CAMPOS | ADRIANO PERIN
The etiologic agent of the Asian soybean rust is the Phakopsora pachyrhizi, which causes a reduction in the photosynthetic leaf area and, consequently, in the crop yield. Chemical control is one of the main measures for its management. The objective of this work was to evaluate the efficacy and selectivity of the fluxapyroxad fungicide on controlling the Asian soybean rust, under the edaphoclimatic conditions of the Cerrado biome. The experiment was conducted in an area under no-tillage system, in the Agricultural Research Center, Rio Verde, Goias, Brazil, during the 2012/2013 crop season, using the cultivar NA7337. A randomized block experimental design was used, with twelve treatments and four replications. The treatments consisted of applications of fluxapyroxad (FX), pyraclostrobin (PT), epoxiconazole (EX) and metconazole (MZ). The average severity of the disease in the plants reached 37% in the Control. All treatments with fungicides differed from the Control. Treatments 9, 10, 11 and 12 provided the greatest rates of soybean rust control. The treatments 10, 11 and 12 had the highest thousand grain weights, and the yields of the treatments 2, 3 and 11, despite higher than the Control, were lower than the treatments 4, 5, 6, 7, 8, 9, 10 and 12, which had statistically equal yields. The increasing in yield, compared to the Control, ranged from 10.05% (pyraclostrobin, epoxiconazole + pyraclostrobin + mineral oil) to 30.55% (pyraclostrobin, pyraclostrobin + fluxapyroxad + mineral oil and pyraclostrobin + metconazole + mineral oil). The highest rates of soybean rust control were presented by fungicides containing fluxapyroxad.
Mostrar más [+] Menos [-]CHARACTERIZATION OF CUCURBIT PRODUCTION SYSTEMS AND DISEASE PREVALENCE IN MUNICIPALITIES IN PERNAMBUCO
2016
GERFFESON THIAGO MOTA DE ALMEIDA SILVA | RAYANNE MARIA PAULA RIBEIRO | AURÉLIO PAES BARROS JÚNIOR | LINDOMAR MARIA DA SILVEIRA | PEDRO MARTINS RIBEIRO JÚNIOR | NEILZA REIS CASTRO DE ALBUQUERQUE
Cucurbits have great economic, nutritional and social importance in the Brazilian semiarid region. In this region, many factors can result in reduced productivity of these crops, especially fungal and viral diseases. Therefore, knowledge of cucurbits is crucial for proper disease management. The objective of this work was to identify the major diseases of cucurbits grown in some municipalities in the Hinterland of the state of Pernambuco. Thus, plant samples were collected with symptoms in crops in the municipalities of Salgueiro, Serra Talhada, Floresta, Petrolândia, Ibimirim, Custódia and Inajá. A questionnaire was also applied to gather information about the production profile of producers. Seven fungal pathogens infecting cucurbits were identified: Pseudoperonospora cubensis, Colletotrichum sp., Podosphaera xanthii, Rhizoctonia solani, Didymella bryoniae, Fusarium sp. e Alternaria sp., and three viruses as well: Papaya ringspot virus - watermelon strain (PRSV-W), Watermelon mosaic virus (WMV), Zucchini yellow mosaic virus (ZYMV). It was found that in small crops, there is limited search for technical information om cropping, and these crops originate mostly from native seeds, in contrast to medium and large producers, who use improved cultivars. The melon and watermelon crops are the most commercially exploited, while pumpkins are used in subsistence agriculture. As for plant health problems, most respondents reported knowing the main diseases that occur in crops and perform disease control based on personal experience and / or through the help of the technical assistance provided by agricultural stores. In a few cases, in large farms, there was an agronomist to assist in this type of control.
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