Comportamento do cafeeiro apoatã em consórcio com culturas anuais

This study was conducted in Adamantina, region of Alta Paulista, São Paulo State, Brazil, from 1989 to 1993. Yield of Apoatã coffee (Coffea canephora Pierre ex Froehner) was evaluated during four years of intercropping with five plant species: IAC 20 - cotton (Gossypium hirsutum L.); cv. Tatu - peanut (Arachis hypogaea L.); IAC 165 - rice (Oryza sativa L.); cv. Guarani - castor bean (Ricinus communis L.) and IAC 100-B - corn (Zea mays L.). The crops were seeded 50 cm apart from coffee canopy. The treatments were arranged in randomized complete block design with five replications. Yield was significantly decreased when coffee was intercropped with castor bean, corn, cotton and peanut, but height and diameter of orthotropic branches were not affected. Linear correlation analysis showed that coffee yield was inversely correlated with the dry biomass of the intercrops.

Métodos de coleta de fezes e determinação dos coeficientes de digestibilidade da fração protéica e da energia de alimentos para o pacu, Piaractus mesopotamicus (Holmberg, 1887)

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Fatores que afetam a oviposição de Bemisia tabaci (Genn.) biótipo B (Hemiptera: Aleyrodidae) na cultura algodoeira

The objective of this work was to evaluate the oviposition behavior of the whitefly Bemisia tabaci (Genn.) biotype B in relation to leaf position, plant age, and adult density on cotton plants. The genotype IAC 22 was used to do the tests. In free-choice tests, 20, 30 and 40 day-old plants were used to evaluate age efects and 40 day-old plants to study egg distribution in the plant and on the leaf surface. In a no-choice test, 20 day-old plants were used to evaluate densities of 50, 100 and 150 adults per plant. The lobe areas on the leaf surface and apical leaves were preferred for whitefly egg laying and therefore more suitable for egg sampling in cotton plants. The 20 day-old plants were preferred for oviposition, and the densities of 100 and 150 adults per plant ensured the number of eggs enough to discriminate cotton genotypes with different whitefly resistance degrees.

Efeito da calagem e sulfato de amônio no algodão. I - Transporte de cátions e ânions no solo

Applying lime on the soil surface in soils managed under no-tillage has caused an excess of basic cations in the most superficial layers of the soil profile. On the other hand, subsoil acidity is considered a constraint to the development of deep plant roots. The objective of this study was to evaluate Ca 2+, Mg 2+, NO 3- and SO 4 2- leaching in the soil profile as affected by liming and top dressing nitrogen fertilization in cotton, grown with straw cover on the soil surface. Cotton plants (Gossypium hirsutum) were grown for 60 days in PVC columns filled with a Distroferric Red Latosol (sand loam Rhodic Oxisol) with liming applied over the straw on the soil surface, incorporated liming 0-20 cm deep, or without liming. Nitrogen was applied at rates of 0, 50, 100 and 150 kg ha -1 as ammonium sulfate. The PVC columns were set up in layers of 0-5, 5-10, 10-20, 20-30 and 30-30 cm, totaling 15.71 dm 3. The ammonium sulfate application caused intense leaching of SO 4 2- in the soil, irrespective of the lime application method. Liming increased the concentration of NO 3 in the 0-20 cm soil layer, whereas the correction of the soil acidity did not affect the NO 3- concentration in the 30-50 cm soil layer. The influence of ammonium sulfate on Ca 2+ leaching below 20 cm was only observed in the soil with incorporated lime. Nitrogen application resulted in extensive Mg 2+ leaching from the soil, regardless of the lime application method. In the soil layer below 30 cm, SO 4 2- presented a higher correlation than NO 3- in the formation of ionic pairs with Ca 2+ and Mg 2+.

Central nifedipine-induced alterations in salivary flow and compounds: Role of nitric oxide

The aim of this study was to examine the role of nifedipine and Nitric Oxide (NO) on salivary flow and compounds (salivary amylase, saliva total proteins, saliva calcium, sodium and potassium). Male Holtzman rats weighting 200-250 g were anesthetized with zoletil 50 mg kg -1 (tiletamine chloridrate 125.0 mg and zolazepan chloridrate 125.0 mg) into quadriceps muscle and stainless steel cannulas were implanted into their lateral ventricle of the brain (LV). Animals in divided group were injected with nifedipine (50 μg μL -1) alone and in combination with 7-nitroindazol (7-NIT) (40 μg μL -1), neuronal NO Sinthase Inhibitor (nNOSI) and Sodium Nitroprussate (SNP) (30 μg μL -1) NO donor agent. As a secretory stimuli, pilocarpine dissolved in isotonic was administered intraperitoneally (ip) at a dosage of 10 mg kg -1 body weight. Saliva was collected for 7 min with four cotton balls weighing approximately 20 mg each, two of which were placed on either side of the oral cavity, with the other two placed under the tongue. Nifedipine treatment induced a reduction in saliva secretion rate and concentration of amylase, total protein and calcium without changes in sodium and potassium concentration in comparison with controls. Co-treatment of animals with nifedipine and SNP retained flow rate and concentration of amylase, total protein and calcium in normal levels. Co-treatment of animals with nifedipine and 7-NIT potentiated the effect of nifedipine on the reduction of saliva secretion and concentrations of amylase, total protein and calcium. Nifedipine (dihydroperidine) calcium-channel blocker widely in use is associated with salivary dysfunction acting in the central nervous system structures. NO might be the mechanism for protective effect against the nifedipine-induce salivary dysfunction, acting in the CNS. © 2006 Asian Network for Scientific Information.

Condutividade hidráulica e resistência à penetraçao do solo influenciada por diferentes sistemas de manejo

Soil management measures that increase the efficiency of organic matter cycling and maintain favorable soil structure are needed for improving soil quality. On the other hand, soil structure degradation due to inadequate soil management systems is widespread. Among the indicators of soil physical quality, saturated hydraulic conductivity and penetration resistance are thought to be sensitive to soil management system. The aim of this work was to study the influence of soil tillage system and organic fertilization on selected soil physical properties after the first year of treatment. The field work was conducted in Selviria, MS, Brazil on an Oxisol. The experimental design was randomized complete blocks with split-plots, with 12 treatments and 4 repetitions. Tillage treatments included conventional ploughing (CT) and direct drilling (DD). Fertilizer treatments were: 1) manure, 2) manure plus mineral, 3) traditional mineral 4) plant residues of Crotalaria juncea, 5) plant residues of Pennisetum americanum and 6) control plot. The plots were cropped to bean in winter and to cotton in summer, and both cultures were irrigated. After one year no significant differences between treatments in mechanical resistance and porosity were found. However, saturated hydraulic conductivity and infiltration were higher in the conventional tillage treatment at the 0.00-0.10 m depth. Moreover, an improvement in soil physical condition by organic fertilizers was shown.

Comparación de tres métodos para estimar estabilidad del rendimiento en nueve variedades de algodón

With the purpose of selecting and recommending promissory cultivars of cotton, Gossypium hirsutum (L) with high yield potential and stability, for crop areas in Venezuela, the yield (seed included) of nine cotton varieties was evaluated. The data from the 1995-96 and 1996-97 cycles was used. The experimental design was a randomized completed block design with four repetitions on twelve environments. Parameters of stability offered by the methods of Eberhart and Russell, (1966), Cruz et al. (1989) and the AMMI model were estimated and compared to determine the best method or combination. There was no coincidence between the best yield varieties, Unellez-2 and the commercial variety Delta Pine 16, in relation to stability criteria. According to Eberhart and Russell, these were classified as stable, while according to Cruz et al. they were adaptive to favorable environments and according to AMMI they were unstable with high interaction,.Of the three methods studied, the AMMI model allowed associating the response of high yield varieties to specific environments, gave more information and was easier to interpret.

Cotton root volume and root dry matter as function of high soil bulk density and soil water stress

Soil compaction reduces root growth, affecting the yield, especially in the Southern Coastal Plain of the USA. Simulations of the root restricting layers in greenhouses are necessary to develop mechanisms which alleviate soil compaction problems. The selection of three distinct bulk densities based on the Standard Proctor Test is also an important factor to determine which bulk density restricts root penetration. This experiment was conducted to evaluate cotton (Gossypium hirsutum L.) root volume and root dry matter as a function of soil bulk density and water stress. Three levels of soil density (1.2, 1.4, and 1.6 g cm-3), and two levels of water content (70 and 90% of field capacity) were used. A completely randomized design with four replicates in a 3×2 factorial pattern was used. The results showed that mechanical impedance affected root volume positively with soil bulk density of 1.2 and 1.6 g cm-3, enhancing root growth (P>0.0064). Soil water content reduced root growth as root and shoot growth was higher at 70% field capacity than that at 90% field capacity. Shoot growth was not affected by the increase in soil bulk density and this result suggests that soil bulk density is not a good indicator for measuring mechanical impedance in some soils.

Propriedades químicas de um latossolo vermelho de cerrado cultivado com algodão sob diferentes preparos e adubações

The high rate of mineralization of organic matter on savannah soils, which is reached fi ve times faster than in temperate regions, leads us to the challenge of electing the best system of management that maintains and/or increase it in soil, guaranteeing its quality and sustainability. In this sense the present research aimed to study the effects of green, organic and mineral manure on the chemical properties on the chemical properties of an Oxisol, on Savannah area, cultivated with cotton (Gossypium hirsutum) under conventional tillage and no-tillage in the pasture fi eld (Brachiaria decumbens) for 20 years. The experimental design was a randomized block design with split plots. The main plots consisted of two treatments: conventional tillage and no-tillage, and the subplots of six treatments: control (no fertilizer), mineral fertilizer recommended for the crop, according to the soil chemical analysis, organic fertilizer (cattle manure - 20 t ha-1), organic fertilizer (cattle manure - 20 t ha-1) + 1/2mineral fertilization recommended according to the analysis of soil, green manure-1 (Crotalaria juncea) and green manure-2 (Pennisetum americanum). There were studied the following soil chemical properties: P, OM, pH, K, Ca, Mg, Al, Al + H, S, exchange capacity cations and base saturation. The soil samples for the analysis were performed on layers of 0,00-0,05 m, 0,05-0,10 and 0,10-0,20 m. Then it came the following conclusions: the fertilization interfere in soil chemical properties and the preparation did not interfere, the cattle manure and its association with the mineral fertilizer caused increasing level elements in the soil, Crotalaria juncea and Pennisetum americanum did not infl uence on soil chemical properties.

Análise geoambiental da região de marília, SP: Suscetibilidade a processos erosivos frente ao histórico de ocupação da área

The study area comprises the western portion of the Marília Plateau, State of São Paulo, southeastern Brazil. The geological substrate encompasses Cretaceous sedimentary rocks of the Bauru Group and local Neocenozoic units like colluvium aprons, fluvial terrace deposits, in situ regoliths, and modern alluvial deposits. In a geomorphologic sense, the study area might be characterized as showing two main pediplanes, viz. P1 Surface (upper) and P2 Surface (lower), both surfaces are presently under dissecation processes. After the 1920's the expansion of the railroad system fostered the removal of the natural vegetation, which in turn was followed by the introduction of coffee, peanut, corn and cotton crops. This intense exploitation was conducted without respect to the soil carrying capacity and its natural susceptibility to erosional processes, including an aggressive form known as voçoroca. As a result, the study shows that the most susceptible material includes colluvium aprons, in situ regoliths, and colluvium-alluvium or alluvium deposits. The most critical situation is in the P2 Surface context, near the bottom of the Marília Plateau scarpment, where surface runoff can be very strong. Another point of active erosion is represented by the exposed walls of gullies and voçorocas, mainly in fluvial reaches subjected to talweg lowering. In a general sense, this study shows current evidence of erosional stability due to the ìntroduction of pastures as a predominant type of land occupation and to a series of erosion control procedures. Among these actions are terrace implantation, construction of small pits for runoff control, natural or induced reforestation by land owners. Despite these efforts, some erosion points remain chiefly in steeper country roads and trail stretches, in areas of concentration of cattle tracks (e.g., near cattle ponds), gullies or voçorocas exposed walls, and badly planned urbanization. The permanence of these erosion points demonstrates the necessity of a continuous monitoring of surface dynamics as well as a rapid and effective intervining measures of erosion and/or silting control.

Índice de infestação e fatores de mortalidade do bicudo-do-algodoeiro (Coleoptera: Curculionidae) no semi-árido do sudoeste da Bahia, Brasil

The boll weevil (Anthonomus grandis Boheman, 1843) (Coleoptera: Curculionidae) is a pest that limits the production of cotton, especially in the North East of Brazil. The present study aimed to estimate the infestation index and natural mortality of boll weevil at Caraibas County, located in the semi-arid of the Southwest ofBahia. The experiment was performed using the cultivar BSR Aroeira, at Fazenda Lagoa Seca, in 2006. Weekly evaluations were performed, in five sampling areas 25m2, collecting blossoms fallen on the ground. The infestation was estimated by counting the oviposition punctures and /or the feeding on blossoms, and also by the presence of one of the phases of the boll weevil in the inside. Mortality factors were studied through the dissection of blossoms, estimating predation, parasitism, dissection and disease. The results obtained allowed to conclude that the boll weevil determines high infestation levels in the region. Parasitism, dissection and predation, following this order, determine high rates of real mortality of the pest. Catolaccus grandis Burks, 1954 (Hymenoptera: Pteromalidae) and Bracon sp.(Hymenoptera: Braconidae) are parasitoids of boll weevil reported in sothwestern Bahia, being the first one the predominant species. © 2009, Sociedad Venezolana de Entomología.

Desenvolvimento de metodologia de criação e multiplicação de Aphis gossypii: Avanços e sucessos

Estudos sobre as mais diversas formas de controle de pragas e utilização de inimigos naturais, exigem artrópodes em quantidade e qualidade. Mediante essa necessidade, o processo de criação e multiplicação de artrópodes, vem ao longo dos anos, passando por significativas transformações. As técnicas de criação e multiplicação de insetos são muito importantes em estudos de biologia e de métodos de controle. A criação e definição de uma metodologia para multiplicação tem sido um grande desafio nos estudos da biologia e da criação de insetos, principalmente, devido a dificuldade de estabelecimento de populações em casa de vegetação e campo. Visando otimizar e adequar uma metodologia de multiplicação de Aphis gossypii (Hemiptera: Aphididae) em condições de laboratório, foi estabelecida uma colônia sobre plantas de algodoeiro (Gossypium hirsutum L. raça Latifolium Hutch) objetivando uma melhoria nas condições de sobrevivência e multiplicação desses insetos, menores influencias dos fatores abióticos, e a potencialização do uso das plantas por um período mais longo. Com o desenvolvimento dessa técnica e dos recursos utilizados na criação, notou-se um incremento na quantidade de indivíduos obtidos, melhor aproveitamento das plantas e diminuição de custos. Dessa forma evitou-se também a migração e infestação de outras espécies de pulgões e a ação de inimigos naturais. Após o estabelecimento da criação, verificou-se que o controle do parasitismo de A. gossypii foi de acordo com as condiçõ es submetida.

Concentrações de ácido giberélico e períodos de estratificação na emergência do porta-enxerto de marmeleiro 'Japonês' (Chaenomeles sinensis)

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Plantas de cobertura e adubação nitrogenada na cultura do algodoeiro

The fiber quality, productivity and favorable climate are considered key points for the development of the cotton crop in the Brazilian Cerrado. This study aimed to evaluate the effect of cover crops and N application in presowing on the cotton crop growth and yield. The experimental design was randomized blocks, consisting of a - three cover crops (radish, white oat and black oat) implanted during the winter period, b - four nitrogen levels (0, 30, 60 and 90 kg ha-1 of N) applied to the millet residues and before cotton sowing. In April 2008, evaluations were realized of plant development and also harvesting was performed of experimental plots of cotton plants. The results showed that the radish provides increased length of branches and cotton bolls of cotton crop, without yield increase, and the use of increasing doses of N up to 90 kg ha-1 decreased the amount of carimã per plant, increasing the number of reproductive branches and cotton yield.