خيارات البحث
النتائج 21 - 30 من 109
FUNGOS MICORRÍZICOS ARBUSCULARES E ATIVIDADE ENZIMÁTICA EM SOLO CULTIVADO NA CHAPADA DO APODI - CE النص الكامل
2011
JAMILI SILVA FIALHO | VÂNIA FELIPE FREIRE GOMES | JOSÉ MARIA TUPINAMBÁ DA SILVA JÚNIOR
This paper has evaluated the alterations in the number of spores of arbuscular mycorrhizal fungi (AMF) and enzymatic activity in soil under cultivation of banana trees in Chapada of Apodi. The hypothesis was tested that the agricultural use causes environmental alterations that they reduce the presence of population of AMF and the microbial activity. An area was selected under cultivation of banana trees (Farm Frutacor) and its control (natural vegetation). Four soil samples were collected in three depths in which analyses were accomplished, the number of spores of AMF by Gerdemann and Nicholson (1964) and enzymatic activity: acid phosphatase, arylsulphatase and b-glucosidase by Tabatabai, (1994). The number of spores of AMF show values decreasing with the rise in depth in area cultivated. The activity of the arylsulphatase and acid phosphatase were stimulated by the competition of the anions H2PO4- and SO4- for the same ranches of adsorption in the colloids of the soil. For b-glucosidase, there was a larger activity in the cultivated area, influenced by the amount and quality of the vegetable residue. The enzymatic activity evidences a difficulty of establishing correlations between the biochemistry and chemistry of the soil in area where the entrance of nutrients is high.
اظهر المزيد [+] اقل [-]CRESCIMENTO E NUTRIÇÃO DE MUDAS DE PINHÃO MANSO EM SUBSTRATO CONTENDO COMPOSTO DE LIXO ORGÂNICO النص الكامل
2011
ROSIANE DE LOURDES SILVA DE LIMA | LIV SOARES SEVERINO | VALDINEI SOFIATTI | HANS RAJ GHEYI | GENELICIO SOUZA CARVALHO JÚNIOR | NAIR HELENA CASTRO ARRIEL
Substrates containing 0, 10, 20, and 40% (v/v) of urban waste compost were evaluated for the production of Jatropha (Jatropha curcas L.) seedlings in polytube containers. At 40 days after planting, growth characteristics and macro nutrient content in shoot were determined. The urban waste compost added to the substrate promoted increase in Jatropha plants growth. The maximum growth was obtained with the estimated dose of 24% of compost mixed with subsoil material. Increments in the dose of compost caused linear increase in K, Mg, and S shoot content, but N and Ca contents were reduced by dilution, as the shoot dry mass increased more than the uptake of those nutrients.
اظهر المزيد [+] اقل [-]FRUTOS-REFUGO DE MELÃO EM SUBSTITUIÇÃO AO FARELO DE TRIGO NA ALIMENTAÇÃO DE VACAS LEITEIRAS النص الكامل
2011
GUILHERME FERREIRA DA COSTA LIMA | JOSÉ GERALDO MEDEIROS DA SILVA | EMERSON MOREIRA DE AGUIAR | MARCELO DE ANDRADE FERREIRA | ADRIANO HENRIQUE DO NASCIMENTO RANGEL | JORGE FERREIRA TORRES
The aim of this paper was to evaluate the performance of lactating 5/8 cross-breed Holstein/ Zebu cows, and digestibility of diets with different levels (0%; 5.5%; 13.0%; 20.5% and 26.0%) of melon (Cucumis melo L.) fruits in replacement to wheat bran, on dry matter basis. Five cows averaging 380 kg and 10 kg of daily milk production were used. The experiment was conducted in a 5x5 latin square design, including five animals, five experimental periods and five levels of melon fruits addition. The length of each period of evaluation was 14 days (seven for the adaptation of the animals to the diets and seven for data collection). The intake of dry matter (DM) (kg/day, %BW and g/kg0.75), organic matter (OM), crude protein (CP), neutral detergent fiber (NDF), total carbohydrates (TCH), ether extract (EE) was unaffected (P>0,05) by the levels of melon fruits (12.52; 3.20; 142.42; 11.62; 1.29; 8.15; 10.21 and 0.41, respectively). Crude protein (CPD) and neutral detergent fiber (NDFD) digestibilities decreased linearly, and the digestibility of non-fiber carbohydrates (NFCD) increased linearly. The estimative for total digestible nutrients (TDN) presented a quadratic response with the addition of increasing levels of melon fruits in the diet. Milk production and fat corrected milk production, averaging 9.09 and 9.78 kg/day respectively, increased linearly with the increment of melon fruits participation in the diets, which points out a possibility for utilization of this co-product to feed dairy cows.
اظهر المزيد [+] اقل [-]ANÁLISE ESPAÇO-TEMPORAL DA QUALIDADE DA ÁGUA NA PARTE ALTA DA BACIA DO RIO SALGADO, CEARÁ النص الكامل
2011
SÁVIO DE BRITO FONTENELE | EUNICE MAIA DE ANDRADE | EVELINE VIANA SALGADO | ANA CÉLIA MAIA MEIRELES | RODOLFO JOSÉ SABIÁ
The aim of this research was to investigate the similarity of water quality in space and time in the upland of Salgado watershed, Ceará, Brazil. Multivariate analysis/Cluster Analysis was used for this investigation. Water samples were took in nine stations, spread out along the rivers during March, May, July, August and September, 2005, totalizing 45 samples. The water quality attributes analyzed were: electrical conductivity (EC), chloride (Cl-), sulphate (SO4-2), soluble orthophosphate (OPS), nitrate (NO3-), dissolved oxygen (DO), bicarbonate alkalinity (BA), total coliforms (TC) and turbidity (T). Four homogeneous groups were identified. The water samples collected at rainfall season defined the dissimilarity of group 1 in relation to the others. This group showed the best water quality due to the dilution of salts. Water samples collected during the end of rain-fall season and began of dry season formed group 2. Waters sampled at dry season in stations located down of discharge point of effluents defined group 3. These stations presented the highest concentrations of Cl-, EC, SO4-2 and TC. The values of NO3- and TC defined the similarity of group 4. Although Cl-, SO4-2, DO, and TC influenced the cluster definition, the most important variables were EC and NO3-. The water quality similarity was defined by two factors: punctual pollution and climatic seasonality.
اظهر المزيد [+] اقل [-]PARÂMETROS PRODUTIVOS E NUTRICIONAIS DO CAFEEIRO SUBMETIDO ADUBAÇÃO NITROGENADA NA REGIÃO DE GARANHUNS النص الكامل
2011
MATHEUS PIRES QUINTELA | TONNY JOSÉ ARAÚJO SILVA | EDNA MARIA BOMFIM-SILVA | ENIO FARIAS FRANÇA SILVA | FELIZARDA VIANA BEBÉ
Among the factors that affect the production of coffee distinguishes itself by its high nitrogen demand. The aim of the current paper was to evaluate the productivity of coffee plants, the leaf N level critical stages of grain maturation and export of N, depending on the nitrogen, in order to optimize its recommendation. The experiment was performed in Garanhuns - PE, in a plantation crop. The experimental design was completely used with six treatments (0; 100; 200; 300; 400 and 500 kg ha-1 of N) and four replications. The productivity with the maximum economic efficiency was of 54 bags for hectare of benefited coffee for an application of 196.43 kg ha-1 of N, which represented a decrease of 41.85% in nitrogen. The critical nitrogen ranged from the filling phase to maturity, and their values, from 25.72 to 27.19 g kg-1 and 29.24 to 29.6 g kg-1. For a dose of 328.62 kg ha-1 of N, it was the largest export of this element by the fruit that was 204.31 kg ha-1 of N.
اظهر المزيد [+] اقل [-]MEDIÇÃO DE ÁREA FOLIAR DE ACEROLEIRA النص الكامل
2011
RAFAELLA RAYANE MACEDO DE LUCENA | THAÍZA MABELLE DE VASCONCELOS BATISTA | JEFERSON LUIZ DOLLABONA DOMBROSKI | WELDER DE ARAÚJO RANGEL LOPES | GARDÊNIA SILVANA DE OLIVEIRA RODRIGUES
The determination of leaf area is of interest to producers and sectors of research, and techniques should be simple, quick and accurate. This study aimed to compare methods for estimating leaf area of Barbados cherry in orchard. 60 leaves were collected randomly, and after collection, were measurements of leaf area by five methods: squares, linear dimensions, leaf area integrator AM 300, leaf disks and Digital Image Analysis (Scanner). All methods were compared with the reference method (scanner), based on the criterion of determination coefficient of linear regression (R2). The method that is closer to the leaf area of reference was the integrator portable AM 300.
اظهر المزيد [+] اقل [-]INCIDÊNCIA DE FUSARIOSE E AVALIAÇÃO DE MÉTODOS DE INOCULAÇÃO DE Fusarium gutiforme EM FOLHAS DE ABACAXIZEIRO النص الكامل
2011
MÔNICA DANIELLY DE MELLO OLIVEIRA | LUCIANA CORDEIRO DO NASCIMENTO | RODRIGO PEREIRA LEITE
The fusariosis, caused by Fusarium gutiforme, causing losses higher than 30% on Brazilian fruits production. The present work had as objective evaluate planting integrated production commercial areas of pineapple, and study effects of inoculation methods in relation leaves base, on disease development. Evaluation disease incidence started 90 after plantation, in monthly intervals, until floral induction treatment, carried through 270 days after plantation. During period of evaluation, lower incidence than 1% during the vegetative cycle was observed. Plants that presented typical symptoms of fusariosis had been eliminated of plantation. It was used pineapple leave type D, cv. Pérola. Leaves were detached, disinfested with sodium hypochlorite at 5,0% for 10 minutes and washed with distilled water. Inoculations were done at two and five centimeters of leaf base. The method used was toothpick with fungus. Evaluations were done 15 days after inoculation, being evaluated lesions area. Higher lesions development was observed in treatment with disk of fungus colony on wound + humid cotton (leaf border). Inoculation position had not significative effects for symptoms development.
اظهر المزيد [+] اقل [-]PERFIL DE PROPRIEDADES LEITEIRAS OU COM PRODUÇÃO MISTA NO NORTE DE MINAS GERAIS النص الكامل
2011
RAFAEL ALVES DE AZEVEDO | THIAGO MEIRELES FELIX | OTAVIANO DE SOUZA PIRES JÚNIOR | ANNA CHRISTINA DE ALMEIDA | EDUARDO ROBSON DUARTE
This study aimed to characterize the production and management of dairy farms in the North of Minas Gerais and to research the relevant problems pointed by cattle breeders. A total of 47 breeders were interviewed and were classified 26 farms producing only milk and 21 producing meat and milk simultaneously. The extensive system (45%) and semi-extensive (46%) were the most frequently related to these farms. The averages of cows in lactation and dairy production were 36.3 animals and 295.26 liters/day, respectively. The natural mating was the most utilized reproductive system. In the herds were used most frequently Gir (42%) and Holstein (35%) bulls and in farms with mist production, the zebu cows were more predominant. The reduced price paid for the milk and the Boophilus microplus infestations were the problems pointed with higher frequency by cattle breeders. During the dry season the forage most utilized was the sugar cane with urea and during the rainy period, continuous grazing was the most common. Acaricides were applied for 93.6% of the farms and only 15 of them have implemented strategic control. Theses results obtained are important to know and to compare the profile of dairy farms in this region, fomenting the search for alternatives to improve the productivity and sustainability of cattle breeders.
اظهر المزيد [+] اقل [-]BALANÇO DE RADIAÇÃO NO PERÍMETRO IRRIGADO SÃO GONÇALO - PB MEDIANTE IMAGENS ORBITAIS النص الكامل
2011
BERNARDO BARBOSA DA SILVA | ALEXANDRA CHAVES BRAGA | CÉLIA CAMPOS BRAGA
The net radiation is of great importance in studies related to energy and mass exchanges between the land surface and atmosphere, although it is not measured routinely in a meteorological network. In this sense, the use of satellite images over the last decade has been increasingly used for its determination. The present study aimed at determining the radiation balance in the Irrigated São Gonçalo Project - PISG and surrounding areas based on satellite images and a few meteorological data measured within the PISG. Landsat 5 Thematic Mapper images available in 2008 and procedures of SEBAL - Surface Energy Balance Algorithm for Land were used for mapping albedo and net radiation. Three selected areas into the study scene were used to discuss the behavior of different components of the radiation balance under different soil cover types. It was observed that the waters of São Gonçalo dam presented albedo in the range of 3.3 to 7,5%, while in the soil with low vegetation cover the albedo ranged between 32 and 38,7% over the studied period. In the irrigated coconut orchard the albedo ranged between 15.0 to 18.7%, while the net radiation values over the dam and the coconut orchard were consistently higher than those in other areas. It was concluded that the irrigated areas have lower albedo and surface temperature and thus increased net radiation, contributing to reduce the air temperature locally.
اظهر المزيد [+] اقل [-]DIFERENÇAS SAZONAIS NO APORTE DE SERRAPILHEIRA EM UMA ÁREA DE CAATINGA EM PERNAMBUCO النص الكامل
2011
PRISCILA SILVA DOS SANTOS | JEFFERSON THIAGO DE SOUZA | JOSIENE MARIA FALCÃO FRAGA DOS SANTOS | DANIELLE MELO DOS SANTOS | ELCIDA DE LIMA ARAÚJO
The aim of this paper was to conduct a temporal evaluation of the deposition of litter in a human- disturbed area of caatinga in a process of natural regeneration for 16 years. The study was conducted at the Institute for Agronomical Research - IPA station in Caruaru, state of Pernambuco. Litter was collected monthly throughout the year on a total area of 5.48 m2. The total litter was kg ha yaer-1 9158.93, consisting of 28.90%, 16.82%, 16.95% and 37.33% of leaves, twigs, seeds and miscellaneous, respectively. There were seasonal differences in the deposition of litter, with higher deposition in the dry season. However, there was no monthly variation in the deposition of litter between the months of the season and, and with the exception of the miscellaneous fraction precipitation, it did not maintain connection with the deposition of litter. The paper concluded that after 16 years of regeneration, the area has anthropogenic litter deposition pattern similar to that recorded in other areas of scrub and other factors related to seasonal work, modeling the deposition of litter and influencing the cycling of matter in dry environments.
اظهر المزيد [+] اقل [-]