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EFFECT OF AQUEOUS EXTRACT OF Prosopis juliflora ON THE CONTROL OF THE MITE Tetranychus bastosi IN PHYSIC NUT Texto completo
2018
MARIA DA PENHA MARTINS DO NASCIMENTO | CARLOS ROMERO FERREIRA DE OLIVEIRA | CLÁUDIA HELENA CYSNEIROS MATOS | CÉSAR AUGUSTE BADJI
The objective of this study was to evaluate the efficiency, phytotoxicity and residual effect of the aqueous extract of leaves of Prosopis juliflora (Sw.) DC (Fabaceae) for Tetranychus bastosi Tuttle, Baker & Sales (Acari: Tetranychidae) on Jatropha curcas L. (Euphorbiaceae). For the evaluation of the control efficiency, physic nut plants were infested with 30 adult mite females and after 12 days were sprayed with the lethal concentrations (m/v) of the extract (LC50 = 53.45% or CL90 = 85.35%) and with distilled water (control), which corresponded to the treatments. After 24, 48, 72, 96 and 120 hours after application of the extract, two leaves of the lower, middle and upper third of the plants were sampled and the live mites were counted per treatment. The evaluation of the residual effect was done three, 24, 48, 96, 192 and 288 hours after spraying. To evaluate the phytotoxic effect of the extract, scores were given according to the intensity of the symptoms in the plants. Control efficiency was verified throughout the evaluated period, with an average of 81.67% for LC50 and 73.05% for LC90, with no significant difference between the evaluation intervals. The extract had a low residual effect on T. bastosi, but at the end of 12 days the average percentage of oviposition reduction of mite was 49.21% and 68.86% for LC50 and LC90, respectively. The plants did not present phytotoxicity. P. juliflora extract presents potential for the alternative control of T. bastosi in physic nut due to its efficiency on the mortality of this mite, oviposition reduction of females and absence of phytotoxic effect in the plants.
Mostrar más [+] Menos [-]GPR 3D PROFILE OF THE ADEQUATENESS OF UNDERGROUND DAMS IN A SUB-WATERSHED OF THE BRAZILIAN SEMIARID Texto completo
2018
ALEXANDRE DE OLIVEIRA LIMA | FRANCISCO PINHEIRO LIMA-FILHO | NILDO DA SILVA DIAS | JOÃO ANDRADE DOS REIS | ANDERSON DE MEDEIROS SOUSA
The conventional method monitoring and adequateness of underground dams requires invasive investigatory actions with in their interior structure and only provides specific information for small volumes. On the contrary, application of non-invasive sensing techniques, such as ground penetrating radar (GPR), makes it possible to investigate and explore underground without affecting their structure. A GRP 3D profile was acquired with the aim to allot and monitor an underground dam in the Brazilian semiarid region in the alluvial sub-watershed of the Riacho Pau Lavrado in the Sertão Central de Lajes region of the state of Rio Grande do Norte in Brazil. The GPR profile records were acquired along an alluvial section, processed using the Reflex 5 software and exported into the Opendetec 4.4.0 software in order to obtain a virtual 3D model. The GPR 3D profile of the alluvial deposits shows irregularities of the crystalline basement and external topographical surface (soil). The interpretation of the alluvial GPR profile allows precise adequateness of the underground dam, which supports an increase in the area of hydric accumulation and promotes low-cost building due to the allocation selected with minor sedimentation.
Mostrar más [+] Menos [-]EFFECT OF SAMPLE RE-SATURATION ON SOIL-WATER CHARACTERISTIC CURVE Texto completo
2018
ÍCARO VASCONCELOS DO NASCIMENTO | THIAGO LEITE DE ALENCAR | CARLOS LEVI ANASTÁCIO DOS SANTOS | RAIMUNDO NONATO DE ASSIS | JAEDSON CLÁUDIO ANUNCIATO MOTA
Soil-water characteristic curve (SWCC) is an important tool for water management in irrigated agriculture. However, factors such as texture and structure of soils influence SWCC behavior. According to the literature, wetting and drying cycles alter SWCC. A similar process of re-saturation and drying occurs during SWCC obtainment under laboratory conditions. Based on the hypothesis that re-saturation process alters SWCC due to clay loss in the sample, this study aimed to obtain the SWCC, S index, and pore size distribution from samples submitted to re-saturation cycles, as well as from not re-saturated samples but under higher matric potentials (-2, -4, -6, -8, and -10 kPa). For this, disturbed and undisturbed soil samples, collected from the A (sandy texture) and Btg (sandy clay loam texture) horizons of a Argissolo Acizentado, were used. After obtaining SWCC, each air-dried soil sample was submitted to particle size and clay dispersed in water analyses to verify whether the soil lost clay. The experimental design was a completely randomized design with two methods of SWCC constructing (with and without re-saturation) and eight replications. The re-saturation process generates a loss of clay in the sample, not causing significant changes in SWCC considering the assessed textural soil classes. In addition, sandy soil samples are more sensitive to changes in pore size distribution when submitted to re-saturation.
Mostrar más [+] Menos [-]OPTICAL MICROSCOPY AND SEM FOR IDENTIFYING CLOGGING MATERIAL IN A DRIP IRRIGATION SYSTEM Texto completo
2018
Maycon Diego Ribeiro | Carlos Alberto de Azevedo | Delfran Batista dos Santos | Flavio Daniel Szekut | Márcio Roberto Klein | Claudia Facini Reis
The aim of this study was to apply optical microscopy and scanning electron microscopy (SEM) techniques to identify and assess dripper clogging of an irrigation system. Three dripper models (Taldrip, Streamline, and Tiran) underwent 1200 hours of irrigation with three types of effluents: treated domestic wastewater, water with a high calcium content, and urban water supply. Samples of the material adhered to the inside of drippers were analyzed by means of the smear method aiming at their biological identification. Other samples were taken to obtain SEM images. The presence of algae, bacteria, and biological components of biofilm was observed in drippers operating with wastewater and water with calcium, this latter in a low number. The formation of biofilm and chemical precipitates of calcium were observed in SEM images, leading to emitter clogging. Optical microscopy and SEM analyses allowed identifying the degree of fouling by biofilm and chemical precipitates in dripper clogging.
Mostrar más [+] Menos [-]NUTRITIONAL EVALUATION OF FORAGE CACTUS FERTIGATED WITH DOMESTIC SEWAGE EFFLUENT Texto completo
2018
MARCÍRIO DE LEMOS | MIGUEL FERREIRA | JOSÉ FRANCISMAR DE MEDEIROS | NILDO DA SILVA DIAS | ÊNIO FARIAS DE FRANÇA E SILVA | RANIERE BARBOSA DE LIRA
The northeastern semiarid region faces some of the droughts of the last centuries, resulting in serious reductions of agriculture yields. The water scarcity for agricultural requires rational use practices and reuse of water, such as use of domestic effluent sewage. Alternatively, the use of treated domestic sewage effluent utilizing for irrigation of forage species, such as the forage cactus, can be highlighted. In order to evaluate the effects of fertirrigation with treated sewage effluent on mineral nutrient composition of forage cactus (Opuntia Tuna L. Mill, Mexican elephant ear), an experiment was carried out utilizing a split plot 3 x (4 + 1) with a randomized complete block design randomized block and four replications, being three planting density (66,667.00, 52,282.00 and 33,333.00 plants ha-1) and two water sources associated with irrigation frequency of plates fixed on 3.5 mm per irrigation (Frequencies of 2.3 days with water tap and 7, 14 and 21 days with Sewage Effluent) and cactus cultivated in Rainfed agriculturerainfed (control). The analyze of the nutritional contents of cladodes indicated that there was a significant effect of the intervals from irrigation events only for Ca and Mg concentrations. The highest levels of Ca and Mg were found with the irrigation frequency of 2.3 using tap water. The macronutrients concentration in greater quantity by the forage cactus were N e, K followed by, Ca, Mg and P. The nutritional balance indicated excess of K and P and deficiency of N, Ca and Mg, in this order.
Mostrar más [+] Menos [-]EROSIVE PROCESS CONTROL IN THE BRAZILIAN SEMIARID REGION Texto completo
2018
JÚLIO CÉSAR NEVES DOS SANTOS | EUNICE MAIA DE ANDRADE | HELBA ARAÚJO DE QUEIROZ PALÁCIO | JOSÉ RIBEIRO DE ARAÚJO NETO | JACQUES CARVALHO RIBEIRO FILHO
The adoption of measures to prevent and control erosive processes requires information about the factors affecting the erosion and the sediment transport conditions. However, the sediment yield of a basin depends on the availability of eroded material and the sediment transport capacity. Thus, the objective of this study was to identify the factors that affect the sediment transport capacity at different spatial scales in an area with caatinga vegetation. The study was carried out in the Iguatu Experimental Basin, in the state of Ceará, Brazil, from 2009 to 2014, by monitoring two scale levels: watershed with 2.06 ha, and erosion plot with 20 m². The variables evaluated for the rainfall events were precipitation, intensity of rainfall, antecedent soil moisture, precipitation of the antecedent five days, consecutive dry days, peak flow, runoff depth, and sediment yield. During the study period, 263 rainfall events (>2 mm) and 86 events generating runoff were recorded. Three Principal Components (PC) were developed using the Principal Component Analysis, which explained more than 79% of the total variance. Variables connected to the kinetic energy capacity of the rainfall to disaggregate soil particles, the energy for sediment transport, and the soil water content were framed in the CP1, CP2, and CP3, respectively. In the evaluated scales, the sediment yield presented a high correlation with the runoff depth, which indicates limiting conditions for sediment yield by the mass flow energy.
Mostrar más [+] Menos [-]MOLECULAR PROFILE, PURITY AND PRESENCE OF TRYPSIN INHIBITORS IN COWPEA PROTEIN ISOLATES Texto completo
2018
KAROLINE DE MACÊDO GONÇALVES FROTA | LAYS ARNAUD ROSAL LOPES | IZABEL CRISTINA VERAS SILVA | JOSÉ ALFREDO GOMES ARÊAS
The most-used preparation process of protein isolates (PI) involves the isoelectric precipitation of the protein. Heating shortens the preparation time but this procedure may affect the purity, yield, molecular profile of the protein, and the activity of the trypsin inhibitor. This study aimed to investigate the effect of heating in the production of cowpea protein isolates. Crude whole beans (WB) were defatted with hexane, and the protein isolates obtained by isoelectric precipitation with (HPI), and without (NHPI) heating. The protein content of the WB and the PI was determined by the micro-Kjeldahl method, and the extraction yield estimated from the protein content at the end of extraction in relation to this content in the raw material. Possible losses of protein fractions were followed by SDS-PAGE, and the trypsin inhibitor activity determined by an enzymatic assay (BAPNA: benzoyl-DL-arginine-p-nitroanilide). Protein content in HPI was 83.3%, less than in the NHPI (92.2%). The HPI yield was lower (40.0%) as compared to the NHPI (42.3%). Electrophoresis indicated bands ranging from 13 to 262 kDa in WB; and the NHPI presented a protein fraction’s profile closer to that of the WB than to the HPI. The WB had the trypsin inhibitor activity, expressed as Trypsin Inhibitory Units (TIU), of 32.5±0.5 TIU /mg-protein; HPI showed 12.7±0.5 TIU /mg-protein (39% of that observed in WB) and the NHPI, 8.3±0.2 TIU /mg-protein (25.5%). Heating reduces the yield and purity of proteins in the isolates. However, the inhibitory activity of trypsin cowpea is most affected by the isolation procedure.
Mostrar más [+] Menos [-]DYNAMICS OF HERBACEOUS VEGETATION IN CAATINGA MANIPULATED WITH GRAZING EXCLUSION UNDER PHOSPHATE FERTILIZATION Texto completo
2018
Pedro Mouzinho de Oliveira Neto | Márcio Vieira da Cunha | Evaristo Jorge de Oliveira | Mércia Virginia Ferreira dos Santos | Janete Gomes de Moura
The semi-arid region accounts for about 70% of the surface area of the Brazilian northeast, and the most important forage resource is the Caatinga, covering approximately 54% of this region. However, about 40% of this vegetation is in secondary succession. The areas in the process of degradation range from low to severe intensity, and total more than 20 million hectares, reflecting the intense use of the land, such as the overgrazing. The objective of this study was to evaluate the influence of different doses of phosphorus (0, 50 and 100 kg P2O5 ha-1 year-1) on the dynamics of herbaceous vegetation at different times of the year, in a Caatinga area manipulated without grazing for four years. The experiment was conducted at the Serra Talhada-UFRPE Academic Unit during the years 2015 and 2016. We used a randomised block design with three blocks and four replicates per block. Phosphate fertilisation in grazing exclusion areas promoted an increase in forage mass of the enriched Caatinga herbaceous stratum at all evaluation times, especially in the dry season of 2016, which showed values above the average of 7950 kg DM ha-1. In addition, it promoted an increase in the participation of buffelgrass in the floristic composition, increasing its involvement in the area to around 74% at the maximum dose of phosphorus used. Thus, phosphate fertilisation at up to 100 kg of P2O5 ha-1 year-1, together with grazing exclusion, can help to recover the Caatinga enriched with buffelgrass and optimise its use by reducing the formation of new grazing areas in the Caatinga.
Mostrar más [+] Menos [-]CHEMICAL, GRANULOMETRIC AND TECHNOLOGICAL CHARACTERISTICS OF WHOLE FLOURS FROM COMMERCIAL CULTIVARS OF COWPEA Texto completo
2018
MAIARA JAIANNE BEZERRA LEAL RIOS | KAESEL JACKSON DAMASCENO-SILVA | REGILDA SARAIVA DOS REIS MOREIRA-ARAÚJO | EVÂNIA ALTINA TEIXEIRA DE FIGUEIREDO | MAURISRAEL DE MOURA ROCHA | JORGE MINORU HASHIMOTO
Flour production through milling is an alternative for the cowpea processing, when the aim is to obtain a product with higher added value. The objective of this work was to determine the chemical composition, the granulometry, and evaluate the microbiological characteristics of whole-bean flours from five cowpea cultivars (BRS Cauamé, BRS Guariba, BRS Xiquexique, BRS Novaera and BRS Itaim). Cowpea beans were dried in a oven (Fanem, 320-SE) at 50 °C for 6 hours, milled in a cyclone-type rotor mill (Tecnal, TE-651/2) and, subsequently, in a pulverizer-type semi-industrial mill (Fritsch, Pulverisette 14) to obtain the flour. The flour centesimal composition, total energetic value, mineral content, granulometry, microbiological characteristics, and technological properties-flour water absorption and solubility in water-were analyzed. All analyzes were performed in triplicate and the results expressed in mean ± standard deviation. The means were compared by the Scott-Knott test (p ≤ 0.05). The flour centesimal composition presented (g per 100 g of flour): 7.13 to 10.33 of moisture, 2.06 to 3.65 of ashes, 1.53 g to 2.90 of lipids, 21.73 to 25.77 of proteins, and 58.08 to 64.02 of carbohydrate. The flours had on average 359.04 Kcal (100 g) and presented high iron, zinc, copper, manganese, phosphorus and magnesium contents. The whole-bean flours from the cultivars BRS Cauamé and BRS Xiquexique are sources of calcium. Regarding the microbiological characteristics, all flours are innocuous. The water absorption index were within 1.77 and 2.20 g g-1 and the water solubility index within 17 and 23%. All whole-bean flours had good nutritional, technological and microbiological characteristics, and thus potential for use in bakery products.
Mostrar más [+] Menos [-]SELECTION FOR THE DEVELOPMENT OF BLACK EYE COWPEA LINES Texto completo
2018
JÉSSICA DANIELE LUSTOSA DA SILVA | KAESEL JACKSON DAMASCENO-SILVA | MAURISRAEL DE MOURA ROCHA | JOSÉ ÂNGELO NOGUEIRA DE MENEZES JÚNIOR | VALDENIR QUEIROZ RIBEIRO
Cowpea bean is a socioeconomically important legume that contribute to generate employment and income. This species presents great grain variability, and the commercial subclass black eye stands out as a very appreciated grain in Brazil and abroad, thus requiring the development of new cultivars. The objective of this work was to evaluate and select lineages of commercial black eye cowpea, based on simultaneous, and direct selection. First, 105 progenies and four controls were evaluated using the Federer's augmented block design. Seventy-seven progenies, selected from this evaluation-first selection cycle-and four controls were evaluated in three environments, using a simple 9×9 lattice design. Based on this evaluation, the second selection cycle was possible, resulting in 24 progenies. The gain by direct selection was lower than the predicted gain for grain yield in the first cycle, indicating that the selection was not effective. This result was probably due to the reduced genetic variability caused by the selection pressure. In the second cycle, the predicted and observed gains were similar, indicating that much of the expected gain was observed. The predicted and observed gains, with simultaneous selection based on the rank sum selection index, were similar in the first and second cycle. The simultaneous and direct selections resulted in genetic gains for grain yield in the two selection cycles, making it possible the selection of high grain yield lineages.
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