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INFLUÊNCIA DE FUNGICIDAS E FOSFITO DE POTÁSSIO NO CONTROLE DA FERRUGEM ASIÁTICA E NA PRODUTIVIDADE DA SOJA
2014
JANDER DA SILVA NEVES | LUIZ EDUARDO BASSA Y BLUM
This study evaluated the effects fungicides with or without association with potassium phosphite on the control of the Asian rust (Phakopsora pachyrhizi) of soybean. Two field tests (‘Coodetec- 219RR’ and ‘Emgopa-313’) were conducted (12/2005-4/2006) in Cristalina (Goiás, Brazil), in a complete ran- domized block design (Nine treatments; five replications). The treatments were with one and two applications of phosphite-K (1192 g a.i. ha-1 P2O5 + 596 g a.i. ha-1 K2O) + vegetable oil (VO - 0.5% v v-1), two applications of traditional fungicides (TF) [pyraclostrobin+epoxyconazole (66.5 + 25 g a.i. ha-1); methyl- thiophanate+flutriafol (300+60 g a.i. ha-1); tebuconazole (100 g a.i. ha-1)], and, one application of TF+phosphite and a second application of phosphite+VO. For ‘Emgopa-313’, product applications were made on V8 and R2 soybean growth stage, while for Coodetec-219RR on R1 and R5. Evaluations of disease severity (%DS) were made each seven days after product applications. After the first product application, all treatments significantly reduced DS. At the end of evaluations only treatments with TF significantly reduced DS. Yield and mass of 1000 seeds were significantly higher for treatments with TF. Phosphite-K applications decreased DS, but did not increase yield and mass of 1000 soybean-seeds.
Show more [+] Less [-]NÍVEL DE DANO ECONÔMICO PARA INSETOS DESFOLHADORES EM FEIJÃO-CAUPI
2014
JAQUELINE ZANON DE MOURA | LUIZ EVALDO DE MOURA PÁDUA | SINEVALDO GONÇALVES DE MOURA | NARA WALLESKA SILVA MONÇÃO RIBEIRO | PAULO ROBERTO RAMALHO E SILVA
The cowpea bean (Vigna unguiculata (L.) Walp.) is often attacked by defoliator insects. There are a great number of species of these defoliator insects and they cause huge damage to the plants. The most important being: Diabrotica speciosa e Cerotoma arcuata (both Coleóptera), Spodoptera frugiperda, Mocis latipes e Spodoptera cosmioides (both Lepidoptera). Understanding the relationship between the plague infestation and the productivity of the culture is one of the keys to the success of the integrate management of the cowpea bean. Studying the artificial defoliation process in order to simulate similar insect damages to the plants is useful. There are few research studies about the artificial defoliation in the cowpea bean plant. So, this study was developed to determine the level of economical damage inflicted by defoliator insects in cowpea bean plants in the Cultivar BR-17 Gurguéia. The experiments were conducted in the do Departamento de Fitotecnia do Centro de Ciências Agrárias da Universidade Federal do Piauí. The defoliation were in the order of 0%; 25%; 50%; 75% and 100%. The experiment was taken 25 days and 40 days after planting the cowpea bean plants. The production loss threshold of the cowpea bean in local condition in Teresina-PI is R$ 61.00.ha-1, which allows, through regression analysis, the following conclusion: the level of control of defoliator insects during the vegetative state is about 60% of defoliation; while in the reproductive state it is about 47%.
Show more [+] Less [-]CHANGES IN THE pH AND MACRONUTRIENTS IN SOIL FERTILIZED WITH HAIRY WOODROSE IN DIFFERENT AMOUNTS AND TIMES OF INCORPORATION
2014
SILVIA BEZERRA DE GÓES | JOSÉ ROBERTO DE SÁ | GUSTAVO PEREIRA DUDA | FRANCISCO BEZERRA NETO | MAIELE LEANDRO DA SILVA | PAULO CÉSAR FERREIRA LINHARES
Organic fertilizing promotes changes in the physical, chemical and biological attributes of soil making it more productive. The objective of this study was to evaluate the effect of different amounts of hairy woodrose (Merremia aegyptia L.) and their times of incorporation on the chemical attributes of an Alfissol Eutrophic cultivated with lettuce. The experiment was conducted from April to June 2006 at the Universidade Federal Rural do Semi-Árido (UFERSA) in Mossoró-RN. The experimental design was complete randomized blocks with treatments arranged in a 4 x 4 factorial with 3 replications. The first factor consisted of four amounts of hairy woodrose incorporated into the soil (2.2, 4.4, 6.6 and 8.8 t ha-1 dry matter) and the second factor was the four times of their incorporations (0, 10, 20 and 30 days before transplanting lettuce). The soil pH remained alkali, decreasing with the amounts of hairy woodrose incorporated into the soil and with the times of incorporation. The contents of N, Ca and Mg in the soil increased with increasing amounts of hairy woodrose and with the times of incorporation in soil. The levels of available P and K increased with increasing amounts of hairy woodrose incorporated into the soil. However, in relation to the incorporation times, they were optimized at 16 and 14 days, respectively, after the manure incorporation. The utilization of hairy woodrose as organic fertilizer, generally, indicated improvement in soil chemical attributes in relation to the original values evaluated before its incorporation.
Show more [+] Less [-]ELABORAÇÃO DE BEBIDA TIPO NÉCTAR DE GRAVIOLA ADOÇADA COM MEL DE Apis mellifera
2014
DYEGO DA COSTA SANTOS | ANGELITA DA SILVEIRA MOREIRA | EMANUEL NETO ALVES DE OLIVEIRA | YVANA MARIA GOMES DOS SANTOS
The objective of this st udy was to prepare drinks type soursop nectars sweetened with honey from Apis mellifera , by use of experimental planning, varying the concentrations of pulp and soluble solids content and evaluate the effect of these in the physical and chemical characteristics of processed drinks. Were used a factorial planning 2 2 with three experiments in central point resulting in seven experiments. The soursop pulp was diluted with potable water to obtain products in the concentrations of 25, 30 and 35% (w/w) of pulp. The correction of soluble solids to 11, 12 and 13 °Brix was made using honey from A. mellifera . It was ob- served that all formulations of drinks type soursop nectar sweetened with honey were in accordance with bra- zilian legislation. The mathematical equations fitted to the data of titratable acidity, total sugar, ratio, brightness and intensity of yellow were significant, and only the models fitted to the values of titratable acidity, total sug- ars and ratio were predictive. The responses of titratable acidity, total sugar, ratio, brightness and yellow color intensity were influenced by factors pulp concentration and total soluble solids content, wherein the concentra- tion of soursop pulp had greater influence on the acidity and the ratio and the content final total soluble solids of the beverages, modified by the addition of honey, showed greater influence on the content of total sugars and lightness values. The yellow intensity response showed influences of both factors.
Show more [+] Less [-]STRAW DEGRADATION AND NITROGEN RELEASE FROM COVER CROPS UNDER NO-TILLAGE
2014
ADRIANO STEPHAN NASCENTE | CARLOS ALEXANDRE COSTA CRUSCIOL | LUIS FERNANDO STONE
Culturas de cobertura são usadas para cobrir o solo e também podem liberar nitrogênio para o solo durante a mineralização. No entanto, é necessário identificar espécies que combinem liberação rápida de nutri- entes com maior persistência da palhada na superfície do solo. O objetivo deste estudo foi investigar a degrada- ção da palha e a liberação de nitrogênio por culturas de cobertura sob plantio direto. O experimento de campo foi conduzido durante dois anos no verão (2008/2009 e 2009/2010) na região do Cerrado do Brasil. O delinea- mento experimental foi em blocos ao acaso no esquema fatorial. Os tratamentos foram a combinação de cinco plantas (quatro espécies de plantas de cobertura 1- Panicum maximum, 2- Brachiaria ruziziensis, 3- Brachiaria brizantha e 4- Pennisetum glaucum [milheto] e pousio como controle) com seis épocas de avaliação (seis pri- meiras semanas após a aplicação de glifosato nessas plantas de cobertura). Entre as espécies avaliadas, Penise- tum glaucum e pousio tiveram rápida degradação da palhada e liberação de nitrogênio. As culturas de cobertura Panicum maximum, Brachiaria brizantha e Brachiaria ruziziensis se destacaram na produção de biomassa e na quantidade de nitrogênio nas suas palhadas, mas apresentaram baixos coeficientes de degradação e persistiram por mais tempo na superfície do solo em relação a Pennisetum glaucum e pousio.
Show more [+] Less [-]RESPOSTAS DA BANANEIRA (Musa sp.), CULTIVAR PACOVAN EM SISTEMAS DE MANEJO COM APLICAÇÃO DE FERTILIZANTE MINERAL E BIOFERTILIZANTE
2014
JOSÉ WILSON GOMES DOS SANTOS | FERNANDO FELIPE FERREYRA HERNANDEZ | BOANERGES FREIRE DE AQUINO | FRANCISCO NILDO DA SILVA | DAVID CORREIA DOS ANJOS | JOSÉ THALES PANTALEÃO FERREIRA
The liquid biofertilizers have been used with relative success in the recovery of banana planta- tions that have low productivity, after long time cultivation. However, there is little information available relat- ed to cultural practices that aim to increase the life of bananeiral. The objective of the present study was to compare areas degraded plantations that have received the application of biofertilizer for a period of two and five years and the area where the culture did not receive this type of application. The study was conducted in year of 2011 in the municipality of Chapada do Apodi Quixeré - CE. It was evaluated the effects of time of ap- plication on soil chemical attribute, biometric measurements of the plant, dry mass production, extraction and export of N, P and K, and the contribution of plant biomass. The experimental design was completely random- ized with three replications. The biofertilizer increased the content of organic matter, exchangeable Ca and K in all soil depths. The levels of disposable P and exchangeable Mg were higher only in the surface layer. The bio- fertilizer contributed to the increase of pH, the CE and Na soil. Plants that received application of the product were higher, with greater weight and number of leaves. The area received more application time showed higher productivity, accumulated 20% more dry mass, extracted more N, P and K soil, more nutrients exported through harvesting and landed larger amount of plant biomass.
Show more [+] Less [-]PACLOBUTRAZOL NO CRESCIMENTO E DESEMPENHO PRODUTIVO DA SOJA SOB DIFERENTES DENSIDADES DE SEMEADURA
2014
LUIZ FERNANDO PRICINOTTO | CLAUDEMIR ZUCARELI
The growth regulators have been used in different cultures as cultural management technique that aims to reduce the size of the plant and also provide physiological changes that promote increases in grain yield. The objective of the study was to evaluate the effects of paclobutrazol on growth and yield performance of soybeans grown under different plant densities. The experimental design was a randomized block in factorial scheme (2 × 4 × 4), with four replications, two populations of plants (250 and 450.000 plants ha - 1 ), four doses of the plant growth regulator paclobutrazol (0, 12.5, 25.0 and 37.5 g ai ha - 1 ) and four stages of application (V 3 , V 6 , R 1 and V 3 + R 1 ). Averages for the effects of stadiums applications and plant populations underwent Scott Knott test at 5% probability of doses and the regulator to regression analysis. The population of 450.000 pl ha - 1 resulted in greater plant height, lodging and most lower productivity of soybeans. The use of paclobutrazol at V 3 soybean crop did not reduce plant height or grain yield, but reduced the percentage of lodging, and in the stadiums full development of culture (V 6 ) or early reproductive period (R 1 ) reduced height and lodging, as well as the grain yield of the crop. Increases in doses regulator paclobutrazol resulted in reducing plant height, lodg- ing and grain yield of soybean.
Show more [+] Less [-]RELATIVE TOXICITY OF MUSTARD ESSENTIAL OIL TO INSECT-PESTS OF STORED PRODUCTS
2014
ADALBERTO HIPÓLITO SOUSA | LÊDA RITA D\u2019ANTONINO FARONI | ROMENIQUE DA SILVA FREITAS
The relative toxicity of the mustard (Brassica rapa L.) essential oil (MEO) on young and old larvae, pupae, and adults of Sitophilus zeamais and Callosobruchus maculatus was determined using concen- tration-response bioassays. The respiration rate of adults was measured to determine its influence on its toxic- ity. Different developmental stages of both species differed significantly in their response to MEO, with the adults being much more susceptible than the immature stages. Although adult mortality did not differ between species, the adult respiration rate of C. maculatus was significantly higher than that of S. zeamais. Thus, the toxicity oil for adults was not influenced by natural respiration rate of species investigated.
Show more [+] Less [-]PROPRIEDADES TERMODINÂMICAS DE SEMENTES DE TUCUMÃ-DE-GOIÁS (Astrocaryum huaimi Mart.)
2014
DANIEL EMANUEL CABRAL DE OLIVEIRA | OSVALDO RESENDE | RAFAEL CÂNDIDO CAMPOS | KELLY APARECIDA DE SOUSA
The fruits and seeds of tucumã-of-Goiás have important nutritional properties and are used in human consumption and feed. Thus, the study of the thermodynamic properties in the drying process is critical to project analysis equipment, preservation and packaging process of seeds. The aim of this study was to determine and evaluate the thermodynamic properties for different hygroscopic moisture contents of seeds tucumãof- Goiás. For the experimental data we used the static indirect at temperatures of 10, 20, 30 and 40 °C and moisture content of 12.8; 8.9; 5.8 and 3.6% dry base (d.b). The model Copace was that got the best fit to hygroscopic equilibrium moisture content. The thermodynamic properties are affected by moisture content, and the latent heat of vaporization of water from the seeds increases with the decrease in the equilibrium moisture content ranging from 3049.00 to 2666.73 kJ kg-1 for moisture content of 3.6 to 12.8% d.b., respectively. The enthalpy and differential entropy are strongly related to the moisture content of seeds. The isokinetic temperature of 210.93 K confirms the chemical linear compensation between differential entropy and enthalpy seeds of tucumã-of-Goiás, the desorption process being controlled by the enthalpy of seeds.
Show more [+] Less [-]ATIVIDADE CELULOLÍTICA DE FUNGOS AEROBIOS ISOLADOS DO RÚMEN DE BOVINOS LEITEIROS ALIMENTADOS COM FORRAGENS TROPICAIS
2014
PATRÍCA NATALÍCIA MENDES ALMEIDA | CLÁUDIO EDUARDO SILVA FREITAS | FLÁVIA OLIVEIRA ABRÃO | IZABELLA CAROLINA OLIVEIRA RIBEIRO | EDVALDO ALVES VIEIRA | LUCIANA CASTRO GERASEEV | EDUARDO ROBSON DUARTE
The objective was to evaluate the cellulolytic activity of aerobic mycelian fungi from dairy cat- tle fed tropical forages. Isolates of fungi were obtained from 30 samples of rumen fluid from cows fed sorghum silage, 32 cows fed on Brachiaria brizantha , 12 heifers receiving sorghum silage and 11 heifers fed cane sugar. The isolation was performed on C solid medium containing cellulose. Were evaluated 49 isolates, 27 Aspergil- lus spp., four Gliocladium spp., six Paecilomyces spp., nine Rhizophus spp. and three Scedosporium . These isolates were incubated in C medium with 1% microcrystalline cellulose as the sole carborno source, and incu- bated at 37°C in triplicate. Cellulolytic activity indices were verified after 24, 48 and 72 hours and calculated by the ratio between degradation halo and colony diameter for comparing in nonparametric tests. The genus Aspergillus , showed higher cellulolytic activity index mean compared to Rhizophus genus (p <0.05). Eight iso- lates of Aspergillus spp. and six of Paecilomyces spp. showed this index higher than one, indicating potential for utilization in ruminant nutrition.
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