Produção de beterraba em função do espaçamento

Atualmente alguns híbridos importados têm substituído as tradicionais cultivares de beterraba de mesa, sem no entanto, desenvolver estudos básicos sobre a melhor densidade de plantio para as condições brasileiras. O objetivo deste trabalho foi avaliar o efeito do espaçamento entre linhas e entre plantas na produção de beterraba híbrido Boro. O experimento foi conduzido em campo da UNESP em Botucatu-SP, de 10 de setembro a 8 de dezembro de 2010. Foram estudados dois fatores, espaçamentos entre linhas (EL) de 20 e 25 cm, e 7,5; 10,0 e 12,5 cm entre plantas (EP), no esquema fatorial 2 EL x 3 EP, totalizando seis tratamentos (populações variando de 246.400 a 513.333 plantas ha-1, considerando-se canteiros com 1,0 m de largura e espaço entre canteiros de 0,3 m). O delineamento experimental foi em blocos ao acaso, com cinco repetições e parcelas de 2 m2. As mudas foram produzidas em bandejas de polipropileno com 288 células. A irrigação foi por aspersão e a adubação foi igual para todos os tratamentos, seguindo a recomendação para o estado de São Paulo. A maior massa fresca por raiz (116,1 g) foi obtida no EL de 25,0 cm. Em relação ao comprimento da raiz, observaram-se diferenças significativas apenas para o EP, sendo que o maior espaçamento, 12,5 cm, resultou em maior comprimento (63,1 mm). Foram obtidos maiores valores de diâmetro das raízes quanto maiores os EP (65,6 mm para 12,5 cm) e EL (63,1 mm para 25 cm). A maior produtividade (44,7 t ha-1) foi obtida no menor EP (7,5 cm), enquanto que o EL não afetou a produtividade. Pode-se concluir que o melhor EP foi de 7,5 cm pela maior produtividade. Quanto ao tamanho da raiz, tanto o maior EL (25 cm) como o maior EP (12,5 cm) resultaram em raízes com maiores massa média e diâmetro.

Produtividade de arroz de terras altas em função de reguladores de crescimento

The use of sprinkler-irrigation and/or high levels of fertilization in upland rice can increase plant height and hence plant lodging. Lodging can be controlled by using growth regulators, in order to reduce plant height. The objective of this study was to evaluate the efficiency of plant growth regulators applied at the stage of panicle primordium differentiation on the reduction of plant height and the impact on grain yield and its components of upland rice cultivar Primavera, under sprinkler irrigation. The experiment was arranged in a 3x4 factorial randomized blocks design with four replications. Treatments consisted of: mepiquat chloride and trinexapac-ethil applied at doses 9, 50, 100, and 200 mg a.i. ha-1, and paclobutrazol at doses of 0, 25, 50, and 100 mg a.i. ha-1. Plant growth regulators reduced rice plant height; increasing doses of regulators reduced upland rice grain yield and its components; trinexapac-ethyl was the most harmful to rice grain yield.In this study, it was not identified the dose of growth regulator that allied reduction in plant height and did not cause decrease in rice yield.

Crescimento e produtividade de cana-de-açúcar em função da disponibilidade hídrica dos Tabuleiros Costeiros de Alagoas

The aim of this study was to evaluate the interaction among meteorological variables and yield components of six sugarcane varieties and to establish appropriate varietal management at the Coastal Tablelands of the Alagoas State (Brazil). The sugarcane planting was carried out in September 2005, and three cane harvests were made in November 2006, 2007 and 2008. The experimental design was in randomized block with six treatments consisting of the varieties RB863129, RB867515, RB92579, RB93509, RB931003 and RB951541, with four replications. The growth variables evaluated were number and length of stalks, leaf area index, and productivity of stalks and sugar. On average, the crop water balance showed water deficit of 869 mm between September and March and excess of 837 mm from April to August. The irregularity of rainfall in the Coastal Tablelands promoted differential responses in the development and productivity of varieties of sugarcane. Varieties RB93509 and RB931003 are considered options for the varietal management in this region.

Suscetibilidade à podridão negra e produtividade de brócolis em função de doses de nitrogênio e potássio

The purpose of this study was to investigate the influence of potassium and nitrogen on the severity of black rot and yield of head. The experiment was carried out in split plots with factorial subplots, in randomized blocks with four replications. In the plots we assessed the influence of inoculation (injured plants with distilled water and inoculated with Xanthomonas campestris pv. campestris) and in the subplots we evaluated the 4 x 4 factorial, potassium doses (0, 275, 550 and 825 kg ha-1) and nitrogen (0, 150, 300 and 450 kg ha-1). The hybrid Broccoli BRO68 was inoculated using the toothpick method at 64 days after sowing. We observed that potassium in the plant reduced the disease, but nitrogen increased disease. We estimated that the highest levels of potassum in the plant reduced the severity of the disease but lack or excess of nitrogen increased disease severity. The highest production of broccoli inflorescence was obtained at doses from 541 to 751 kg ha-1 of K2O and 286 to 328 kg ha-1 of N. However, when considering a balanced fertilization to obtain higher yield and size of inflorescences and greater resistance to black rot, the ideal doses are 283 kg ha-1 of N and 550 kg ha-1 of K2O.

Teor de nitrogênio inorgânico no solo em função de plantas de cobertura, fontes de nitrogênio e inibidor de nitrificação

A utilização de plantas de cobertura pode alterar a rela-ção NO3-:NH4+ no solo, proporcionando maiores quantidades de NH4+ e podendo viabilizar o desenvolvimento de culturas que absorvem mais e preferem esta forma de nitrogênio (N), como o arroz. Objetivou-se avaliar a influência da interação de plantas de cobertura e fontes de N, com e sem inibidor de nitrificação (dicianodiamida), em sistema plantio direto (SPD). O experimento foi realizado em 2009/2010, em Botucatu (SP), em Latossolo Vermelho distroférrico cultivado por seis anos no SPD. O delineamento experimental foi em blocos casualizados, em esquema de parcela subdividida, com quatro repetições. As parcelas foram constituídas por seis espécies de plantas de cobertura do solo (Urochloa brizantha, U. decumbens, U. humidicola, U. ruziziensis, Pennisetum americanum e Crotalaria spectabilis) e as subparcelas por sete formas de fertilização nitrogenada, aos 0 e 30 dias após a emergência (DAE) do arroz [1 - controle, sem aplicação de nitrogênio; 2 - nitrato de cálcio (40 + 40 kg ha-1); 3 - nitrato de cálcio (0 + 80 kg ha-1); 4 - sulfato de amônio (40 + 40 kg ha-1); 5 - sulfato de amônio (0 + 80 kg ha-1); 6 - sulfato de amônio + dicianodiamida (40 + 40 kg ha-1); e 7 - sulfato de amônio + dicianodiamida (0 + 80 kg ha-1)]. O uso do inibidor de nitrificação e o cultivo de C. spectabilis proporcionaram maiores teores de amônio no solo. A aplicação da fonte amoniacal sem inibidor em dose total aos 30 DAE e com inibidor tanto parcelada quanto em dose total proporcionaram os maiores teores de nitrato no solo.

Biodiesel de buriti em trator: desempenho em função do tipo de diesel e da proporção de mistura na operação de preparo do solo

Pós-graduação em Agronomia (Ciência do Solo) - FCAV

A aplicação do principio da função social da empresa nos empreendimentos recuperados por trabalhadores: um estudo comparado entre Brasil e Argentina

Pós-graduação em Direito - FCHS

Zeros da função zeta de Riemann e o teorema dos números primos

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Verificação da dureza de gessos em função da compatibilidade com materiais de moldagem à base de borracha

Currently the most widespread material used in dies is gypsum that together with its simple technique has very satisfactory mechanical, chemical and physical properties. However, its compactibility with the impression materials can compromise the die surface quality. In our work, we studies the hardness of the two gypsum types: Type III (die stone) and type IV (improved die stone), as well as the influence of the contact with three types of impression materials: polymerized silicone for condensation (Xantopren), polysulfide (Permlastic) and polymerized silicone by addition (Provil). As comparison parameter gypsum was used in contact with a glass surface…(Complete abstract click electronic access below)

Qualidade de sementes de soja convencional e transgênica em função da dessecação das plantas com glyphosate

Pós-graduação em Agronomia (Agricultura) - FCA

Desempenho agronômico de feijão e milho em cultivo solteiro e consorciado, em função da população de plantas de feijão

Pós-graduação em Agronomia - FEIS

Estimativa da produtividade de trigo em função da adubação nitrogenada utilizando modelagem neuro fuzzy

Currently new techniques for data processing, such as neural networks, fuzzy logic and hybrid systems are used to develop predictive models of complex systems and to estimate the desired parameters. In this article the use of an adaptive neuro fuzzy inference system was investigated to estimate the productivity of wheat, using a database of combination of the following treatments: five N doses (0, 50, 100, 150 and 200 kg ha(-1)), three sources (Entec, ammonium sulfate and urea), two application times of N (at sowing or at side-dressing) and two wheat cultivars (IAC 370 and E21), that were evaluated during two years in Selviria, Mato Grosso do Sul, Brazil. Through the input and output data, the system of adaptive neuro fuzzy inference learns, and then can estimate a new value of wheat yield with different N doses. The productivity prediciton error of wheat in function of five N doses, using a neuro fuzzy system, was smaller than that one obtained with a quadratic approximation. The results show that the neuro fuzzy system is a viable prediction model for estimating the wheat yield in function of N doses.

Demanda energética na colheita de híbridos de milho para silagem em função do estádio de maturidade e tamanho de partícula

Corn is the crop most used for making silage. The efficiency of the process should also be evaluated by cost per kg of dry matter harvested (kgDM). The objective of this study was to evaluate energy consumption in the harvest of corn hybrids for silage depending on the texture of the hybrid, four and three harvest maturities of particle sizes - Tp was used a tractor Massey Ferguson MF 610 model 86 cv. Cutting and harvesting the forage harvester is used model JF92 Z10. To obtain data on fuel consumption (CC) and time spent for each plot, we used a flow meter, installed near the fuel filter of the tractor. The experimental design was completely randomized in a split plot. The interaction between factors triple stage hybrid * Harvest * Tp. The velocity and displacement of the tractor were different for the maturities for hybrid hard texture. The CC schedule for hybrid dent increased harvest maturity earlier and at lower Tp. Consumption was lower by kgDM later maturity, hard texture and bite respectively. The theoretical power was higher in earlier maturity and yield were higher for hybrid hard texture in the most advanced. The CC was lower in late maturity and the hybrid hard texture can be used for silage in relation to the Cc and income in later maturity in higher Tp.

Produtividade e qualidade de grãos de canola em função da adubação nitrogenada e sulfatada

The canola (Brassica napus, L.) cultivation was encouraged for grain and oil production at the 80's, and it is also considered a good option for crop rotation. The nitrogen is one of the most required nutrients by the plant to increase its production, while sulfur is essential to provide seed quality. Thus, the objective of this study was, at Cerrado region, evaluate the effects of nitrogen and sulfur fertilization at yield and contents of oil and crude protein in the grains. We also sought relate to grain yield the S content in the soil and concentrations of N and S in the diagnosis leaf. The experiment was conducted in Uberaba County, State of Minas Gerais, Brazil, in an Oxisol, utilizing the Hyola 401 hybrid. The treatments consisted in a factorial scheme 5 x 4 (five N rates: 0, 60, 100, 140 and 180 kg ha(-1) and; four S rates: 0, 15, 30 and 60 kg ha(-1)) in a randomized blocks design, with four replicates. The nitrogen and sulfur fertilization increased canola grain yield, without significantly alter contents of oil and crude protein. Rates higher than to 140 kg ha(-1) of N and 15 kg ha(-1) of S provided grain yield above 1100 kg ha(-1). Plots with yield higher than to 1000 kg ha(-1) presented foliar concentration of N above 52 g kg(-1). The highest S content was observed at the 0.15-0.30 m layer, proving the sulfate anion mobility. The lowest grain yield were observed when the S content in the soil at this layer were less than 4 mg dm(-3). The N concentrations in the diagnostic leaf and S-SO4-2 content in the 0.15-0.30 m layer correlated positively with crop yield.

Produção de repolho em função de doses e fontes de potássio em cobertura

The objective of this research was to evaluate the effects of rates and sources of potassium in top dressing on yield of cabbage hybrid Kenzan. Two experiments were conducted (15/07 to 22/11/2010 and 28/09/2010 to 27/01/2011) and nine treatments, resulted from a factorial 4 rates (45; 90; 135 and 180 kg ha(-1) of K2O) x 2 sources (KCl and K2SO4) + 1 control (without K in top dressing) were evaluated at randomized block design, with 4 replicates. After the harvest, fresh and dry weight of cabbage head and of external leaves; leaf number (from cabbage and external); diameter and height of cabbage head were evaluated. It was evaluated soil chemical characteristics at the end of first experiment and content of macro and micronutrients in plants. It was observed that potassium rates and sources did not influence most of evaluated characteristics. K content in plant increased linearly with KCl application. Results obtained show that, probably, it is not necessary application of K in top dressing when base fertilization is done with this nutrient, besides existing recommendations for this crop.