Weed suppression in the formation of brachiarias under three sowing methods

The success of conservation systems such as no-till depends on adequate soil cover throughout the year, which is possible through the use of cover crops. For this purpose the species belonging to the genus Urochloa has stood out by virtue of its hardiness and tolerance to drought. Aiming ground cover for the no-till system, the objective was to evaluate the establishment of two species of the genus Urochloa, in three sowing methods, in the weed suppression and the sensitivity of these forages to glyphosate. The study design was a randomized block with a 2 x 3 x 3 factorial arrangement, in which factor A was composed of Urochloa ruziziensis and Urochloa hybrid CIAT 36087 cv. Mulato II, factor B was formed by sowing methods: sown without embedding, sown with light embedding and sown in rows, and factor C was composed of three doses of glyphosate (0.975, 1.625 and 2.275 kg ha(-1) of acid equivalent). For determination of weed suppression, assessment of biomass yield and soil cover was performed, by brachiaria and weeds, at 30, 60, 90, 120 and 258 days after sowing. Visual assessment of the desiccation efficiency at 7 and 14 days after herbicide application was performed. It is concluded that embedding Urochloa seeds stands out in relation to sowing in the soil surface. Urochloa ruziziensis is more efficient in the dry weight yield, weed suppression, in addition to being more sensitive to glyphosate herbicide.

Atributos do solo e componentes produtivos da soja: Uma abordagem linear, multivariada e geoestatística

Pós-graduação em Agronomia - FEIS

Formas orgânicas e inorgânicas de fósforo no solo em função de plantas de cobertura e de adubação nitrogenada

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Tractor perfomance as a function of speed and seeder s tire inflation pressure

O desempenho de tratores agrícolas em condições de campo resulta da interação entre pneu e rodado, influenciado pela velocidade de deslocamento. O objetivo deste trabalho foi avaliar o desempenho de um trator agrícola sob diferentes pressões de inflação dos pneus da semeadora (518, 483, and 414kPa) e em duas marchas que proporcionaram velocidades de 3,0 e 6,0km h-1. O experimento foi realizado no campus de Jaboticabal da Universidade Estadual Paulista (UNESP). O delineamento experimental utilizado foi fatorial inteiramente casualizado (3x2), com quatro repetições. A força de tração foi influenciada pela marcha e pela potência exigida; no entanto, a pressão de inflação do pneu da semeadora não alterou esses parâmetros. Além disso, o consumo de combustível foi influenciado apenas pela marcha do trator. O consumo de energia foi maior com o aumento da velocidade, ocasionada pela mudança de marcha. A velocidade de deslocamento foi maior para a pressão de 518kPa, em razão da menor patinagem da semeadora promovida por essa pressão. A patinagem do trator não foi alterada pelos fatores testados.

Avaliações de estratégias de recuperação de pastagens com a introdução de leguminosas

Com o objetivo de avaliar a incidência populacional de plantas daninhas em diferentes manejos de implantação de Stylosanthes guianensis cv. Campo Grande em pastagem de Brachiaria decumbens. Realizou-se um experimento na AgênciaPaulista de Tecnologia dos AgronegóciosExtremo Oeste no município de Andradina/SP emfevereiro de 2011. Utilizou-se o delineamento experimental em blocos ao acaso em esquema de parcelas subdivididas, com quatro repetições e compostos por sete tratamentos (parcelas principais) e duas testemunhas: T1=Plantio direto com dessecação ½ dose de glifosato; T2=Plantio direto sem dessecação; T3=Plantio direto com escarificação do solo; T4=GradagemRome + Plantio direto; T5=Sistema convencional; T6=Brachiaria decumbens e T7= Estilosantes Campo Grande (dessecação com glifosato). Foi avaliado a massa seca de espécies infestantes em diferentes manejos de implantação de Estilosantes Campo Grande, aos 15 dias após semeadura. Os resultados foram submetidos à ANOVA para comparação múltipla de médias, a 5% de significância pelo teste de Tukey. Os T2, T3 e T6 apresentaram uma maior massa seca de espécies infestantes, foram diferentes estatisticamente dos demais (P<0,05), porém não houve diferença significativa entre eles (P>0,05). A massa seca das monocotiledôneas é praticamente toda de Brachiaria decumbens e das dicotiledôneas foi insignificante.

Micronutrientes e biorregulador via foliar em diferentes estádios de desenvolvimento de cultivares de feijão, visando produção e qualidade de sementes

Pós-graduação em Agronomia - FEIS

Modelagem do aporte de sedimentos aplicada à bacia hidrográfica contribuinte da PCH Costa Rica (MS) e proposta de mitigação do assoreamento

Pós-graduação em Engenharia Mecânica - FEG

Acúmulo de cádmio, crômio e níquel e isolamento de micro-organismos potenciais para biorremediação em área agrícola

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Desempenho técnico e econômico de forrageiras tropicais em sistema integrado de produção no cerrado de baixa altitude

Pós-graduação em Agronomia - FEIS

Formas de N-orgânico em latossolo em função de nitrogênio e de plantas de cobertura em pré-safra do milho

Pós-graduação em Agronomia (Produção Vegetal) - FCAV

Custos energéticos do agroecossistema pinhão-manso e milho: comparativo entre o sistema de condução sequeiro e o irrigado

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Efeito de dois sistemas de manejo do solo nas propriedades físico-hídricas, desenvolvimento radicular e produtividade do milho

Corn cultivation is part of crop rotation used by irrigation farmers from the southwestern region of São Paulo state, Brazil, who use no-tillage soil management as a kind of sustainable use of soil. The effect of this conservative practice on physical and hydrical properties of the soil, root development and corn crop yield compared to the conventional management was the objective of this work. The experiment was held at the Buriti-Mirim Farm, Angatuba, SP, Brazil, using an irrigated area with a center pivot system and two types of soil management: conventional and no-tillage systems. Although the no-tillage management had higher soil density and less water availability, no significant difference was found for both management systems concerning soil resistance to penetration, root development and crop yield. In both systems of soil management, 90% of roots were concentrated in the first 0-20cm of soil layer.

Métodos de determinação da densidade do solo em diferentes sistemas de manejo

Soil bulk density is an attribute often used to characterize soil physical structure, being an indicator of soil compaction. The objective of this study was to compare the values ​​of bulk density measured by the paraffin sealed clod and volumetric ring methods in conventional, no-tillage and minimum tillage systems on a Dystroferric Red Nitosol, clayey, in Botucatu, SP. The experiment design was a 3x2 factorial arrangement in randomized block with four replications. The density values ​​obtained by the paraffin sealed clod method were statistically higher than those obtained by the volumetric ring method. There was no difference between the managements when comparing the values ​​of soil density obtained by the paraffin sealed clod method. The soil under conventional management showed lower density when comparing the values ​​of soil density obtained by the volumetric ring. The volumetric ring method was more sensitive to show differences between the management systems than the paraffin sealed clod method.

Características agronômicas e demanda energética de cultivares de soja sob efeito dos sistemas de preparo do solo

The aim of this study was to evaluate the influence of preparation: intermediate grade, minimum tillage and no-till on the agronomic characteristics and energy demand of transgenic soybean cultivars and non-GMO soybeans. Soil preparation aims at improving physical, chemical and biological conditions, aiming at good emergence and plant development. The different types of tillage may interfere with the agronomic characteristics and productivity of plants, and in energy use which can cause variation in production costs. Genetically modified plants can be one of the alternatives for reduction of production costs in crops by reducing pesticide applications, enabling higher productivity with less environmental impact. The test was conducted in 2010/2011 at the agricultural Experimental Farm Lageado, belonging to the Faculty of Agronomic Sciences – UNESP, located in the city of Botucatu, SP in an area using no-till systems for the past 12 years. The experiment was carried out in a 3 x 2 factorial, randomized treatments were comprised of three soil preparation systems, minimum cultivation, intermediate grade preparation and no-till, with two cultivars of soybeans: MGBR-46 Conquest (conventional), Valuable RR (Transgenic). The data obtained was submitted to variance analysis using Tukey test at a 5% probability. With the results analyzed it might be observed that there was no significant difference between treatments, in the variables, the percentage of soil cover, final soybean plant population, grain yield and plant height. The results obtained show that the no-till system resulted in higher productivity than conventional tillage and minimum cultivation. The higher specific energy use per area was observed in minimum cultivation with a chisel plough, when compared to the preparation across the grid. The greatest fuel consumption was to treat minimum cultivation with chisel plough. The highest values were found in the skating system of minimum cultivation, being greater in conventional tillage system. It is more satisfactory for the producer to sow transgenic soy using a no-till system, because productivity retrieved from that system compensates for fuel expenditure.

Demanda energética em diferentes manejos de solo e híbridos de milho

This study aimed to account the energy balance of six different farming systems: CMT (minimum tillage with transgenic corn); CMNT (minimum tillage with non-transgenic corn); PCT (conventional tillage with transgenic corn); PCNT (conventional tillage with non-transgenic corn); PDT (no-tillage system with transgenic corn) and PDNT (no-tillage system with non-transgenic corn). The study was carried out at the Experimental Farm Lageado FCA/Unesp, Botucatu - SP. The energy balance was performed by subtracting the total energy inputs by the total energy output. Energy efficiency was calculated by dividing the total energy output by the total energy inputs. The total values ​​of energy inputs and outputs were expressed in MJ.ha-1 (mega joules per hectare). To calculate the energy inputs were accounted the fuel consumption and lubricants, depreciation energy of machinery and implements, manpower and agricultural inputs. The energy outputs were calculated according to the maize yield. The result shows that the system PDT was the system that had better energy efficiency and the system that had the lowest efficiency was the PCT system. The system with lower energy demand was the PDT and the greatest demand was PCNT.