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PRODUCTION AND CHARACTERIZATION OF CELLULOLYTIC ENZYMES BY ASPERGILLUS NIGER AND RHIZOPUS SP . BY SOLID STATE FERMENTATION OF PRICKLY PEAR Полный текст
2016
TAMIRES CARVALHO DOS SANTOS | GEORGE ABREU FILHO | AILA RIANY DE BRITO | AURELIANO JOSÉ VIEIRA PIRES | RENATA CRISTINA FERREIRA BONOMO | MARCELO FRANCO
Prickly palm cactus husk was used as a solid - state fermentation support substrate for the production of cellulolytic enzymes using Aspergillus niger and Rhizopus sp. A Box - Behnken design was used to evaluate the effects of water activity, fermentation time and temperature on endoglucanase and total cellulase production. Response Surface Methodology showed that optimum conditions for endoglucanase production were achieved at after 70.35 h of fermentation at 29.56°C and a water activity of 0.875 for Aspergillus niger and after 68.12 h at 30.41°C for Rhizopus sp. Optimum conditions for total cellulase production were achieved after 74.27 h of fermentation at 31.22°C for Aspergillus niger and after 72.48 h and 27.86°C for Rhizopus sp . Water activity had a significant effect on Aspergillus niger endoglucanase production only. In industrial applications, enzymatic characterization is important for optimizing variables such as temperature and pH. In this study we showed that endoglucanase and total cellulase had a high level of thermostability and pH stability in all the enzymatic extracts. Enzymatic deactivation kinetic experiments indicated that the enzymes remained active after the freezing of the crude extract. Based on the results, bioconversion of cactus is an excellent alternative for the production of thermostable enzymes.
Показать больше [+] Меньше [-]CORN DEVELOPMENT AND PRODUCTION IN FUNCTION OF SOURCES OF NITROGEN FERTILIZERS AND DOSES Полный текст
2016
FERNANDO CASTRO OLIVEIRA | MAURILIO DE SOUSA NETTO | LUCAS DA SILVA ARAUJO | ANDRÉ CIRILO DE SOUSA ALMEIDA | PEDRO MARQUES DA SILVEIRA | PAULO CÉSAR RIBEIRO DA CUNHA
Nitrogen (N) is one of the nutrients that have the most significant effect on corn grain productivity increase. In order to evaluate the effect of sources of N topdressing and doses in the grown corn culture, in a conventional till system, it was installed an experiment in the city of Urutaí, Goiás, in the 2012/13 crop, in clayey textured Red Latosol. The experimental design was a randomized complete block design with four replications, with the treatments arranged in a factorial 3 x 5, consisting of three sources (coated urea, urea and ammonium sulfate) and five doses (0, 60, 120, 180 and 240 kg ha - 1 ) of N, topdressing, applied in the surface and in a single dose, when the corn plants were in V 4 stage. The hybrid used was the P3646H. We evaluated the following characters: stem diameter, plant height, height of ear insertion, leaf N, number of ears per plant, ear length, number of rows per ear, number of grains per row, 100 grains mass and grain productivity. All characters have a response to nitrogen fertilization and only the height of ear insertion showed no significant difference between sources. The source coated urea showed the best results, indicating that its use may be compensatory, especially in favorable conditions for the NH 3 volatilization, as the application of high doses of N in the surface.
Показать больше [+] Меньше [-]NUTRIENT CONTENT IN SUNFLOWERS IRRIGATED WITH OIL EXPLORATION WATER Полный текст
2016
ADERVAN FERNANDES SOUSA | LINDBERGUE ARAÚJO CRISOSTOMO | OLMAR BALLER WEBER | MARIA EUGENIA ORTIZ ESCOBAR | TEÓGENES SENNA DE OLIVEIRA
Irrigation using produced water, which is generated during crude oil and gas recovery and treated by the exploration industry, could be an option for irrigated agriculture in semiarid regions. To determine the viability of this option, the effects of this treated water on the nutritional status of plants should be assessed. For this purpose, we examined the nutritional changes in sunflowers after they were irrigated with oil - produced water and the effects of this water on plant biomass and seed production. The sunflower cultivar BRS 321 was grown for three crop cycles in areas irrigated with filtered produced water (FPW), reverse osmosis - treated produced water (OPW), or ground water (GW). At the end of each cycle, roots, shoots, and seeds were collected to examine their nutrient concentrations. Produced water irrigation affected nutrient accumulation in the sunflower plants. OPW irrigation promoted the accumulation of Ca, Na, N, P, and Mg. FPW irrigation favored the accumulation of Na in both roots and shoots, and biomass and seed production were negatively affected. The Na in the shoots of plants irrigated with FPW increased throughout the three crop cycles. Under controlled conditions, it is possible to reuse reverse osmosis - treated produced water in agriculture. However, more long - term research is needed to understand its cumulative effects on the chemical and biological properties of the soil and crop production.
Показать больше [+] Меньше [-]SEED MORPHOMETRY AND GERMINATION OF Aechmea costantinii (Mez) L. B. Sm. (BROMELIACEAE) Полный текст
2016
PETRÚCIO ALEXANDRE FONSECA RIOS | JOAO CORREIA ARAÚJO NETO | VILMA MARQUES FERREIRA | MARIA INAJAL RODRIGUES DA SILVA DAS NEVES
The potential economic and environmental benefits brought by bromeliads production are significant. It is noteworthy that the high degree of degradation of some ecosystems as the Atlantic forest involve reduction of these species. This factor has been worsened by the elevated degree of endemism of these plants, e.g. Aechmea costantinii (Mez) L. B. Sm., which is a high ornamental potential bromeliad but understudied. Thus, the present research aimed to characterize physical and morphological features of A. costantinii fruit and seeds, describing the different stages of post - seminal development, as well as evaluating seed germination behavior with respect to temperature and light. For this purpose, we used fruit and seeds freshly harvested from an Atlantic Forest fragment, located in the city of Maceió, Alagoas State, Brazil. Tests were carried out under a completely randomized design, in a 6x4 factorial scheme (temperature x light) with four replications of 25 seeds. The polyspermic fruit are of tricarpellate/triloculate type and originated from inferior ovary, containing an average of 73 elliptical and mucilaginous seeds with basal embryo. The germination is epigeal - type and occurs in a great intensity and high speed at 35 °C, regardless light presence or quality.
Показать больше [+] Меньше [-]EVALUATION OF THE REACTION OF WATERMELON PARENT AND F1 PLANTS TO Meloidogyne enterolobii Полный текст
2016
LÉIA SANTOS DAMACENO | MANOEL ABÍLIO DE QUEIROZ | RITA DE CÁSSIA SOUZA DIAS | JOSÉ MAURO DA CUNHA E CASTRO | FÁTIMA ALVES TEIXEIRA
The aim of this study was to evaluate the performance of progenies from Citrullus lanatus var. lanatus (cultivated watermelons) when crossed with progenies from C. lanatus var. citroides (fodder watermelon with a historic of resistance to the nematode Meloidogyne enterolobii). The parents and their F1s were evaluated for resistance to this nematode. In the initial stages of eleven treatments, watermelon seedlings plantlets were transplanted to plastic bags of six kilograms once the first leaves developed. Ten inoculated plants with 5,200 eggs in the soil near the stem of the plant and four non-inoculated ones were used in each treatment, in a complete block design. Sixty-two days after sowing, the following characteristics were evaluated: the length of the aerial part of the plant (LAP, in m), fresh mass of the aerial part (FMAP, in g), root fresh mass (RFM, in g), egg number (EN) and reproduction factor (RF). A comparison between the averages of inoculated and non-inoculated plants was performed using Scott-Knott test at 5% and the diallelic analysis was performed using the GENES program. The morphological characteristics did not allow for the identification of the parent plants or the F1s with respect to nematode resistance, but the variables EN and RF were useful for such identification. The analyses of the general and specific combining abilities indicate highly significant effects with respect to this resistance, showing additive gene effects as well as dominance and epistatic gene effects, allowing for identification of parents and F1s that can be used in watermelon breeding programs to improve resistance to the M. enterolobii.
Показать больше [+] Меньше [-]CRUDE PROTEIN LEVELS IN THE DIETS OF TAMBAQUI, COLOSSOMA MACROPOMUM (CUVIER, 1818), FINGERLINGS Полный текст
2016
CHARLYAN DE SOUSA LIMA | MARCOS ANTONIO DELMONDES BOMFIM | JEFFERSON COSTA DE SIQUEIRA | FELIPE BARBOSA RIBEIRO | EDUARDO ARRUDA TEIXEIRA LANNA
Tambaqui is intensively farmed because of its production characteristics; however, there is a lack of information lacks about the nutritional requirements of this species. The present study aimed to evaluate the effects of various crude protein (CP) levels in the diets of tambaqui fingerlings. A total of 750 fingerlings with an initial weight of 0.35 ± 0.09 g were selected in a completely randomized design with six treatments (experimental feeds with 20%, 24%, 28%, 32%, 36%, and 40% CP), five replicates, and 25 fish per experimental unit. Performance, survival rate, carcass yield, body composition, protein deposition, body fat, and nitrogen retention efficiency were evaluated after 45 days. CP levels did not affect the following: feed conversion, survival rate, moisture content, and carcass yield. However, with increasing CP levels, protein efficiency ratio decreased. Weight gain, feed conversion, and specific growth rate improved until CP levels of 31.57%, 28.90%, and 31.12%, respectively, were achieved. Quadratic effects of elevated CP levels on body fat and body fat deposition were observed at minimum CP levels of 26.55% and 23.77%, respectively; and on body protein, body protein deposition, and nitrogen retention efficiency at maximum CP levels of 29.26%, 32.50%, and 27.21%, respectively. We conclude that a CP level of 31.57% is recommended for the diets of tambaqui fingerlings weighing between 0.35 and 15.11 g, which corresponds to a digestible energy:CP ratio of 9.50 kcal DE/g CP.
Показать больше [+] Меньше [-]SOURSOP LIQUOR PROCESSING: INFLUENCE OF THE PROCESS VARIABLES ON THE PHYSICAL AND CHEMICAL CHARACTERISTICS Полный текст
2016
EMANUEL NETO ALVES DE OLIVEIRA | DYEGO DA COSTA SANTOS | YVANA MARIA GOMES DOS SANTOS | PAULO RENATO BUCHWEITZ | JOSIVANDA PALMEIRA GOMES
Soursop is a well - appreciated tropical fruit, both in natura and in the form of juices and nectars. Despite its wide acceptance, there is lack of its use in the preparation of other products, such as alcoholic beverages. The objective of this study was to prepare soursop liquors by varying the concentrations of pulp and sucrose syrup with different contents of total soluble solids and to evaluate the effects of these on the physical and chemical characteristics of the beverages. In the production process, the pulp (300, 400 and 500 g) was macerated with distilled alcohol for 20 days, after which it was filtered, added to the syrup (50, 60 and 70 ° Brix), bottled in polyethylene bottles and subjected to an accelerated aging. All drinks resulted in alcohol levels (15.25 to 16.69% v/v) and total sugars (12.63 to 17.97%) in accordance with the standards required by law. The experiments made with the lowest concentration of pulp showed the highest yields (84.17 and 85.25%). First - order models with interactions and 95% confidence intervals were obtained. The pulp consisted of the most significant factor, influencing the largest number of responses (yield, alcohol content, dry residue, titratable acidity, titratable acidity/soluble solids ratio and luminosity). The larger coefficient of determination (R 2 ) values were found in the models adjusted to the data of yield, dry residue, total soluble solids, titratable acidity and total sugars, which were significant and predictive, showing values greater than 0.97.
Показать больше [+] Меньше [-]MORPHOLOGICAL CHARACTERISTICS AND FORAGE PRODUCTIVITY OF IRRIGATED CACTUS PEAR UNDER DIFFERENT CUTTING INTENSITIES Полный текст
2016
GUILHERME FERREIRA DA COSTA LIMA | MARGARETH MARIA TELES REGO | FERNANDA DANIELE GONÇALVES DANTAS | RAIMUNDO NONATO BRAGA LÔBO | JOSÉ GERALDO MEDEIROS DA SILVA | EMERSON MOREIRA DE AGUIAR
This study evaluated the effect of different cutting intensities and years of harvesting on the morphological characteristics and production of fresh (FMP) and dry matter (DMP) of cactus pear cv. Gigante (Opuntia ficus-indica Mill) under conditions of irrigation, high planting density and fertilization, with 12 months of regrowth. The experimental was completely randomized in a factorial design (3 × 2) with 12 replicates. The treatments were three cutting intensities (preserving the mother cladode (PMC), primary cladodes (PPC), or secondary cladodes (PSC)), and two years of harvesting. The soil was classified as Cambisol Haplicum and the irrigation water was classified as C4S1 (EC 5.25 dS.m-1) density of 50,000 plants ha-1. The research evaluated plant height, number of cladodes per plant (NCP), length, width, perimeter and thickness of the cladodes, cladode area (CA), cladode area index (CAI), FMP and DMP. There was no significant interaction between treatments (P > 0.05) for the variables plant height, NCP, CAI and FMP. The variables related to cladode morphology showed a significant interaction (P < 0.05). The treatment PSC resulted in a greater DMP (P < 0.05) with a mean of 27.17 Mg ha-1 yr-1, compared to PPC (18.58 Mg ha-1 yr-1) or PMC (11.78 Mg ha-1 yr-1). The treatment PSC promoted greater NCP and forage productivity at harvest and can be considered as a management practice for the sustainability of cactus pear cv. Gigante under irrigation. The more important morphological characteristics were also influenced by the lower cutting intensities.
Показать больше [+] Меньше [-]MECHANICAL HARVESTING OF COFFEE IN HIGH SLOPE Полный текст
2016
FELIPE SANTINATO | ROUVERSON PEREIRA DA SILVA | VANTUIR DE ALBUQUERQUE SILVA | CARLOS DIEGO DA SILVA | TIAGO DE OLIVEIRA TAVARES
Brazilian coffee farming is carried out both on flat and steep lands. In flat areas, mechanized operations are intensive; however, in steep slope areas, certain mechanized operations cannot be performed, such as harvesting. Based on this, the industry has developed machinery to harvest coffee in areas with up to 30% slope. However, harvesters have their efficiency and operational performance influenced by land slope. Thus, this study aimed to evaluate the operational performance and harvesting efficiency of a steep-slope harvester under different situations, using different speed settings. The experiment was carried out in the county of Santo Antônio do Amparo, state of Minas Gerais, Brazil, using five coffee stands with 10, 15, 20, 25 and 30% slope. Evaluations were performed with a self-propelled harvester (Electron, TDI®, Araguari, MG, Brazil) at three rotation speeds (600, 800 and 1.000 rpm) and two ground speeds (800 and 1.000 m h-1). The results showed the lower speed (800 m h-1) was suitable for 10% slope areas since the amount of fallen coffee berries. For areas of 20% slope, harvesting time was 21.6% longer than in flatter areas. Downtime varied from 10.66 to 29.18% total harvest due to a higher number of maneuvers.
Показать больше [+] Меньше [-]SPACE-TIME DEPENDENCE OF JATROPHA GROWTH PARAMETERS GROWN IN BRAZILIAN SEMIARID Полный текст
2016
ANDRÉ QUINTÃO DE ALMEIDA | RODOLFO MARCONDES SILVA SOUZA | SÉRVULO MERCIER SIQUEIRA E SILVA | IVAN SOUTO DE OLIVEIRA JUNIOR | FARNÉSIO DE SOUSA CAVALCANTE | JOSÉ ALISON DA SILVA MELO
Jatropha has emerged as a source of power generation in the semiarid region of Brazil. The objective of this study was to evaluate, using geostatistics, the spatial variability of stem diameter, plant height and seed weight of jatropha (Jatropha curcas L.) grown under rain fed conditions in Serra Talhada, Pernambuco state, Brazil. At 545, 905 and 1265 days after sowing (DAS), the stem diameter and plant height of 340 plants were measured with a digital caliper and a tape measure. At 545 DAS, the fruits of 306 plants were collected, the seeds extracted and their weights measured with a precision balance. For each date analyzed, the spatial dependence of the plant characteristics was evaluated from the adjustment of the experimental semivariogram. The spherical model was adjusted for modeling the spatial distribution of cultural parameters. The range of plant height reduced by an average of 37% from 545 DAS when compared to 905 and 1265 DAS, while for the stem diameter this parameter remained practically constant. Geostatistics can be employed to assist in future sampling and to identify areas with different patterns that can occur in the jatropha planting.
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