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SOIL MICROBIOLOGICAL ACTIVITY AND PRODUCTIVITY OF MAIZE FODDER WITH LEGUMES AND MANURE DOSES Texto completo
2018
Charlley de Freitas Silva | Erika Valente de Medeiros | Marthony Dornelas Santana | Maysa Bezerra de Araújo | Argemiro Pereira Martins Filho | Mácio Farias de Moura
SOIL MICROBIOLOGICAL ACTIVITY AND PRODUCTIVITY OF MAIZE FODDER WITH LEGUMES AND MANURE DOSES Texto completo
2018
Charlley de Freitas Silva | Erika Valente de Medeiros | Marthony Dornelas Santana | Maysa Bezerra de Araújo | Argemiro Pereira Martins Filho | Mácio Farias de Moura
Maize is an important cereal and it is widely consumed in the world, both as food for humans and animals. Nitrogen (N) is a nutrient required in large quantities by maize, but unfortunately, soils are limited in meeting this need. Nodulating legumes can serve as a source of Nitrogen, because they are symbiotically associated with bacteria capable of fixing atmospheric N. Another important source of this nutrient is cattle manure, which is widely used in agriculture. The objective of the present study was to evaluate the effect of using legumes and cattle manure on the production as well as the microbial and biochemical quality of the soil used for maize cultivation. The experiment was conducted using a randomized complete block design, in a sub-subdivided plot scheme (2x4) +2, two leguminous plants (pigeon pea and macassar bean), four doses of cattle manure (0, 20, 40 and 60 t ha-1) and two controls; one with mineral fertilization and the other cultivated without the use of fertilizers. Treatment using a manure dose of 60t ha-1 and pigeon pea legume, recorded higher dry mass production per plant. The increase in manure doses was directly proportional to the length and weight of the cobs for the two legumes. The enzymatic activities were affected by the different doses and legumes, with greater results being recorded at the 60 t ha-1 dose with the macassar legume. The use of legumes with manure improved maize production as well as the microbiological and biochemical quality of soils.
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NILE TILAPIA FED ENZYME COMPLEX ADDED AT DIFFERENT LEVELS AND PROCESSING STEPS Texto completo
2018
MARCELO GASPARY MARTINS | GUILHERME DE SOUZA MOURA | ANDRE LIMA FERREIRA | MARCELO MATTOS PEDREIRA | EDUARDO ARRUDA TEIXEIRA LANNA
NILE TILAPIA FED ENZYME COMPLEX ADDED AT DIFFERENT LEVELS AND PROCESSING STEPS Texto completo
2018
MARCELO GASPARY MARTINS | GUILHERME DE SOUZA MOURA | ANDRE LIMA FERREIRA | MARCELO MATTOS PEDREIRA | EDUARDO ARRUDA TEIXEIRA LANNA
Enzyme activity in solid-state fermentation complex added to diets before and after extrusion process and its influence on Nile tilapia (Oreochromis niloticus) performance were evaluated. The following enzymes were analyzed: b-glucosidase, pectinase, xylanase, endoglucanase, amylase, protease, and phytase. The fish were fed five experimental diets: a control diet (without enzyme), two test diets supplemented before extrusion (400 and 800 ppm SSF), and two test diets after extrusion or “on top” (400 and 800 ppm SSF). The experiment had a completely randomized design with four replicates and seven fish per tank. Average initial weight was 10.37 ± 0.95 g, and fish were fed four times a day to satiation for 56 days. The following performance parameters were evaluated: final weight, weight gain, feed conversion, survival, specific growth rate, and body composition. The results were compared using ANOVA and Tukey’s test at p<0.05. All the enzymes showed partial or total losses of activity when subjected to the extrusion process, except phytase. No differences were observed for survival, water quality parameters, and body composition. On-top inclusion provided a better performance, which is observed through increases in final weight, weight gain, and feed conversion. As a result, 800 ppm of enzyme complex SSF should be added "on top", that is after extrusion, to improve tilapia performance and, consequently, contribute to the fish farming financial efficiency.
Mostrar más [+] Menos [-]Nile tilapia fed enzyme complex added at different levels and processing steps
PROBIOTIC POTENTIAL OF Bacillus cereus AGAINST Vibrio spp. IN POST-LARVAE SHRIMPS Texto completo
2018
JULIANA MARIA ADERALDO VIDAL | MAURÍCIO NOGUEIRA DA CRUZ PESSÔA | FERNANDO LEANDRO DOS SANTOS | PAULO DE PAULA MENDES | MIKO SHINOZAKI MENDES
Bacillus spp. have been used against diseases caused by bacteria that affect cultured shrimp, providing beneficial effects on the host shrimps by altering their microbial community, and improving zootechnical indexes. The objective of this work was to evaluate the effects of a diet supplemented with Bacillus cereus-a bacterium with probiotic potential-on post-larvae Litopenaeus vannamei shrimps grown in laboratory. The experiment lasted for fifteen days and consisted of six treatments-control (T1), probiotic (T2), Vibrio parahaemolyticus (VP) (T3), probiotic and VP (T4), V. alginolyticus (VA) (T5), and probiotic and VA (T6). The survival rate, weight gain, colonization capacity of the probiotic bacteria, pathogen count, and histopathological lesions were evaluated. There was no significant difference (p=0.05) in survival between treatments. The groups with pathogens and without probiotics presented lower weight gain. The result of the Bacillus cereus count in the treatments T2, T4 and T6 were significantly different (p<0.05), the probiotic bacteria were more aggressive in competing for space and nutrients when compared to V. parahaemolyticus than when compared to V. alginolyticus. Animals fed with the probiotic presented lower counts of these pathogens than those fed without the probiotic (p<0.05). No histopathological lesions were found in the organs and tissues of the shrimps. Bacillus cereus showed a high colonizing capacity in post-larvae shrimps, causing a significant reduction of pathogens, probably by secreting antimicrobial substances and the competitive exclusion, which justifies their use as probiotic bacteria.
Mostrar más [+] Menos [-]SILICON FERTILIZATION AND SEED MICROBIOLIZATION ON DISEASE SEVERITY AND AGRONOMIC PERFORMANCE OF UPLAND RICE Texto completo
2018
IVANEIDE DE OLIVEIRA NASCIMENTO | ANTÔNIA ALICE COSTA RODRIGUES | HEDER BRAUN | CEALIA CRISTINE SANTOS | ARICLÉIA DE MORAES CATARINO
Rice is one of the world’s most consumed cereals, however, its production is affected by fungal diseases. Thus, the objective of this work was to evaluate the severity of diseases and grain yield potential of upland rice with silicon fertilization combined with seed microbiolization with Bacillus methylotrophicus isolates. Two experiments were conducted, one in Igarapé do Meio, Maranhão (MA), Brazil, with rice seeds of the variety Palha-Murcha and one in São Bento MA with rice seeds of the variety BRS-Primavera. A randomized block experimental design in a split-plot arrangement with five replications were used in both experiments, with agro-silicon rates (0.0, 1.0, 2.0, 4.0 and 6.0 Mg ha-1) in the plots and microbiolized and non-microbiolized rice seeds with B. Methylotrophicus at concentration of 108 CFU ml-1 in the subplots. The seedling emergence, grain yield, number of panicles, plant height, plant dry weight and severity of brown leafspot, leaf scald and grain spot were evaluated. Soil fertilization with agro-silicon affected positively the plant height of the variety Palha-Murcha and the number of panicles, plant dry weight and grain yield of the variety BRS-Primavera, and negatively the germination of the variety BRS-Primavera. Leaf scald severity in the variety BRS-Primavera reduced with microbiolized seeds with B. methylotropicus. Microbiolization with B. methylotropicus had no effect on severity of brown leafspot and grain spot in the varieties evaluated.
Mostrar más [+] Menos [-]ROCKET PRODUCTION IN A LOW COST HYDROPONIC SYSTEM USING BRACKISH WATER Texto completo
2018
José Eustáquio Campos Júnior | José Amilton Santos Júnior | Juliana Bezerra Martins | Ênio Farias de França e Silva | Ceres Duarte Guedes Cabral de Almeida
The production of vegetables in communities of family farmers in semiarid regions is limited due to rudimentary cultivation practices and systems, water scarcity, and excess salts in the water and soil. Thus, the objective of this work was to evaluate the production of rocket (Eruca sativa L. cv. Folha Larga) in a low cost hydroponic system, considering strategies for the use of brackish water in the nutrient solution. The experiments were conducted in complete randomized designs, in 6×2 factorial arrangements, with five replications, using rocket plants grown in different nutrient solutions, consisting of six salinity levels (1.5, 3.0, 4.5, 6.0, 7.5, and 9.0 dS m -1) and two circulation frequencies of the nutrient solution (twice a day, at 8:00h, and 16:00h; and three times a day, at 8:00h, 12:00h, and 16:00h). In Experiment I, the nutrient solution lost by evapotranspiration was replenished with the respective brackish water used in its preparation; and in Experiment II it was replenished with public water (0.12 dS m -1). The shoot and root fresh and dry biomass of the plants and their respective dry weight proportions, and biometric variables were evaluated. Replenishing of the nutrient solution with public water resulted in lower losses in biomass and plant growth. The increases in circulation frequency of the nutrient solution did not affect the biometric variables, however, the plants prioritized shoot biomass development to the detriment of the root when using high circulation frequencies.
Mostrar más [+] Menos [-]AGRONOMIC PERFORMANCE OF COWPEA ELITE LINES IN THE STATES OF MINAS GERAIS AND MATO GROSSO, BRAZIL Texto completo
2018
VANET BATISTA DE SOUZA | ABNER JOSÉ DE CARVALHO | KAESEL JACKSON DAMASCENO-SILVA | MAURISRAEL DE MOURA ROCHA | MARLON LOPES LACERDA | ISRAEL ALEXANDRE PEREIRA FILHO
The objective of this work was to evaluate the agronomic performance of erect and semi-erect cowpea elite lines grown in the States of Minas Gerais and Mato Grosso, Brazil. The experiments were conducted in Jaíba, Janaúba, Sete Lagoas (Minas Gerais), Primavera do Leste and Nova Ubiratã (Mato Grosso), with 20 genotypes of cowpea, arranged in a randomized block design with four replications. The data were subjected to individual and joint analyses of variance and means grouped by the Scott-Knott test (p<0.05). The plant growth habit, lodging, cultivation value, pod length and bean yield were evaluated. The lines MNC04-768F-21 and MNC04F-795F-168 had the highest bean yield in the experiments conducted in Mato Grosso, and their growth habit, lodging and cultivation value were similar to those of the cultivar BRS-Guariba. The lines MNC04-769F-30, MNC05-795F-154 and MNC04-769F-49 and the cultivar BRS-Tumucumaque had the highest bean yield in the experiments conducted in Minas Gerais. However, the cultivars BRS-Guariba, BRS-Tumucumaque, BRS-Novaera, BRS-Itaim and BRS-Cauamé and the lines MNC04-792F-143 and MNC04-792F-144 showed satisfactory bean yield and good growth habit, plant lodging and cultivation value in the State of Minas Gerais, especially in the northern region of the state (Jaíba and Janaúba), representing good alternatives for the genotypes recommended for this region.
Mostrar más [+] Menos [-]FRUIT YIELD AND NUTRITIONAL CHARACTERISTICS OF SWEET PEPPER GROWN UNDER SALT STRESS IN HYDROPONIC SYSTEM1 Texto completo
2018
NADIELAN DA SILVA LIMA | ÊNIO FARIAS DE FRANÇA E SILVA | DIMAS MENEZES | TEREZINHA RANGEL CAMARA | LILIA GOMES WILLADINO
Irrigation with brackish water is common in the semiarid region of the Brazilian Northeast, potentiating the process of salinization of the soil in these areas. The hydroponic system stands out as an important strategy for crop management in semiarid regions, since crops show greater tolerance to the salt stress under hydroponic conditions, which minimize the effects of soil salinization. Thus, the objective of this work was to evaluate the effects of salt stress on the growth, fruit yield and mineral nutrition of sweet pepper in hydroponic system, using brackish water and coconut fiber substrate. The experiment was conducted in Recife, State of Pernambuco, Brazil (8°3'15''S, 34°52'53''W). A randomized block experimental design in a 5x2 factorial arrangement with five replications was used, consisting of five water salinity levels of the nutrient solution (2.0; 3.5; 4.5; 5.5 and 6.5 dS m-1) and two sweet pepper cultivars (Bruno and Rubia). The increasing salinity level of the nutrient solution decreased the fruit yield of the cultivars evaluated, reduced the potassium, phosphorus and sulfur, and increased the sodium and chlorine contents in the leaf tissues. The Ca contents of the cultivar Bruno decreased with increasing salinity, and increased in the cultivar Rubia. The cultivar Rubia stood out with the highest fruit yield and ionic selectivity, accumulating high amounts of potassium and calcium and maintaining low Na and Cl contents. The fruit yield of the cultivar Rubia (39.9 t ha-1) grown under solution with electrical conductivity of up to 3.5 dS m-1, denotes the potential viability of growing this cultivar under hydroponic conditions.
Mostrar más [+] Menos [-]MACHINE TRAFFIC AND SOIL PENETRATION RESISTANCE IN GUAVA TREE ORCHARDS Texto completo
2018
Wilson José Oliveira de Souza | Danilo Eduardo Rozane | Henrique Antunes de Souza | William Natale | Paulo André Fernandes dos Santos
The study was conducted in irrigated commercial orchards of ‘Paluma’ and ‘Pedro Sato’ guavas, which were mapped with a Garmin GPS unit (Cx60). Sixty five sampling points were marked on a 21 x 21 m sampling grid. Gravimetric humidity and soil penetration resistance (SPR) were evaluated with the help of an automated penetrometer rod with a type 3 cone at a 45º angle (maximum SPR 15,100 kPa). Data with non-normal distribution were analyzed by geostatistics and interpolation by ordinary kriging. SPR values were higher where machine traffic occurs than on the lines where the crop is planted. There was spatial variability of the SPR among the layers evaluated, with the layer between 0.10-0.20 m, on the line of the machine traffic, presenting a higher SPR (>4000 kPa).
Mostrar más [+] Menos [-]PREDICTION OF PHENOTYPIC AND GENOTYPIC VALUES BY BLUP/GWS AND NEURAL NETWORKS Texto completo
2018
ALISSON ESDRAS COUTINHO | DIOGO GONÇALVES NEDER | MAIRYKON COÊLHO DA SILVA | ELIANE CRISTINA ARCELINO | SILVAN GOMES DE BRITO | JOSÉ LUIZ SANDES DE CARVALHO
Genome-wide selection (GWS) uses simultaneously the effect of the thousands markers covering the entire genome to predict genomic breeding values for individuals under selection. The possible benefits of GWS are the reduction of the breeding cycle, increase in gains per unit of time, and decrease of costs. However, the success of the GWS is dependent on the choice of the method to predict the effects of markers. Thus, the objective of this work was to predict genomic breeding values (GEBV) through artificial neural networks (ANN), based on the estimation of the effect of the markers, compared to the Ridge Regression-Best Linear Unbiased Predictor/Genome Wide Selection (RR-BLUP/GWS). Simulations were performed by software R to provide correlations concerning ANN and RR-BLUP/GWS. The prediction methods were evaluated using correlations between phenotypic and genotypic values and predicted GEBV. The results showed the superiority of the ANN in predicting GEBV in simulations with higher and lower marker densities, with higher levels of linkage disequilibrium and heritability.
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.
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