The content of this thesis is to compare the soil erodobility in conventional (CT) and soil protection tillage (minimum tillage-MT) in relation to soil organic matter (SOM) in the location of interest - Studená. The soil protection tillage has been used there since 1994 together with conventional. In 2009, the two variants of soil samples were taken from soil depths 0.05, 0.15 and 0.25 m. All soil properties, which may affect erosion or which are affected by it, were analyzed from these soil samples. In particular, this thesis focuses on the relationship between tillage and soil organic matter. There were studied some chosen physical properties as specific gravity and size fraction less than 0.01 mm just in relation to fractions of SOM and soil aggregations stability. Physical-chemical properties have been analyzed more deeply. Of these, special attention was paid to the soil organic matter by establishing a number of parametres and comparing them.

Quantitative and qualitative Soil Organic Matter (SOM) properties were observed in the soil samples of a medium-term field experiment (Cambisol ? Studena, Czech Republic) and an exact field experi?ment (Chernozem ? Gross Enzersdorf, Austria) in the year 2005 considering different soil tillage systems (conventional and minimum tillage). Except the standard parameters, soil organic matter content and quality in particulate water stable aggregates size fractions was additional determinated for Cambisol. Cambisol showed more favourable values of both quantitative and qualitative SOM parameters in minimum tillage system compared to those in conventional tillage system. SOM quality in the water stable aggregates fractions was better in minimum tillage compared to conventional tillage. Cambisol also showed that SOM in aggregates fractions is much more quality compared to SOM in the original soil samples. Chernozem showed higher values of both quantitative and qualitative SOM parameters in conventional tillage compared to those in minimum tillage but the differences are not high. It can be said that Chernozem organic matter reaction to tillage technology changes is slower and of minor rate in comparison with that of Cambisol organic matter. The results of quantitative and qualitative parameters do not conform to the generally recognised values for the Chernozem soil type.

The continued spread of glyphosate-resistant common waterhemp [Amaranthus tuberculatus (Moq.) Sauer (syn. rudis)] and Palmer amaranth [Amaranthus palmeri (S. Wats.)] have complicated weed control efforts in soybean and corn production in Illinois. A thorough understanding of the weed biology of these species is fundamental in developing effective weed management strategies. The determination of emergence patterns as well as the influence of tillage practices on soil microclimate and soil seed bank will allow control strategies to be implemented at the most effective timing. Field experiments were conducted in southern Illinois throughout the growing season of 2013 and 2014 on two separate sites with populations of common waterhemp and Palmer amaranth. Three tillage treatments were evaluated: no-tillage; early tillage, preferably performed around a recommended soybean planting date of May 1st; and late tillage, preferably performed on June 1st to simulate a late soybean planting. Amaranthus seedlings were identified and enumerated in the center 1 m2 quadrat of each plot within a 7-day interval from April through November or first frost. All weed seedlings were removed from the plot area after each enumeration. Soil temperature and soil moisture were recorded hourly throughout the experiment using data loggers established in the plot area. First emergence of common waterhemp occurred earlier in the season than did Palmer amaranth. In 2013, initial emergence of common waterhemp and Palmer amaranth was observed at the first and second week of May, respectively. In 2014, initial common waterhemp emergence was observed in late April, while Palmer amaranth initial emergence was similar to previous year. Palmer amaranth emerged over a longer period compared to waterhemp. By the end of June, 90% of common waterhemp had emerged regardless of tillage or year. By the same measure, Palmer amaranth emergence was extended to the third week of July and second week of August in 2013 and 2014, respectively. Soil temperature did not differ across tillage treatments in both years. On the other hand, differences in soil moisture were observed, mostly over two weeks following each tillage operation. The single best predictor for common waterhemp emergence was soil temperature (weekly highs and lows) followed by soil moisture. For Palmer amaranth emergence the single best predictor was spikes in soil moisture (high for the week). In 2013, common waterhemp emergence was initially positively and later in the growing season negatively interacted with maximum temperature 13 days prior to counts, with temperatures above 30 C observed with decreased emergence (R2 = 0.35). In the same year spikes in soil moisture interacted with Palmer amaranth emergence were those observed 11 days before each seedling enumeration date (R2 = 0.30). In 2014, with first common waterhemp emergence in April, a positive interaction to high soil temperature was initially observed followed by a positive interaction to minimum temperatures later in the season (R2 = 0.55). Spikes in soil moisture observed 2 weeks prior to emergence and weekly high temperatures 8 days prior to emergence were the best predictors of Palmer amaranth emergence in 2014 (R2 =0.37). Soil seed bank depletion was also estimated by comparing field emergence with greenhouse experiment results of soil seed bank estimation. Greater emergence of common waterhemp from the soil seed bank was observed in early tillage in 2013 and no-tillage in 2014 than late tillage, respectively; for Palmer amaranth, the greatest emergence from the soil seed bank was observed in no-tillage and late tillage in 2013, and no-tillage, in 2014. The emergence patterns observed in this research suggest that although common waterhemp and Palmer amaranth exhibit discontinuous emergence throughout the growing season, greater attention should be placed on managing peaks of emergence from late April to late July, which is critical to provide a foundation for early-season weed management. Furthermore, knowledge regarding the emergence patterns of common waterhemp and Palmer amaranth combined with monitoring environmental factors such as soil moisture and soil temperature may assist efforts for scouting fields to determine the likely presence of these weed species. The timing of viable postemergence herbicide options for control of glyphosate-resistant waterhemp and Palmer amaranth is critical and monitoring weather patterns to direct scouting efforts may improve the timeliness of these postemergence applications.

Since agriculture began, field management has been at the forefront of expanding food production beyond previous limitations. Agricultural productivity is closely related to the physical, chemical, and biological properties of the soil. Landscape position and field management are among primary factors affecting these soil properties. Delineation of topographic positions of the field surface by shape (i.e., convex, concave, and linear) characterizes areas that may accumulate or lose soil and nutrients either during a discrete event or cumulatively over several growing seasons. Increased soil compaction, degradation of soil structure, and erosion have all been attributed to declining agricultural production. In addition to the physical disturbance from cultivation, erosion and deposition of soil components in different landscape positions explain a large part of the heterogeneity of soil properties across an agriculture field. In response to this, conservation tillage techniques, precision agriculture, and other novel management strategies have been developed to reduce negative impacts conventional row crop production such as nutrient pollution and compaction while optimizing farmer inputs. The objective of this project was to evaluate effects of topographic position and conservation tillage techniques on soil physical, chemical, and biological properties on the field scale as well as correlate certain soil attributes with suspended soil runoff collected during the sprinkle infiltration test. Soil fertility sampling was completed every fall from 2011 to 2014 and additional sampling of soil physical properties was taken in the spring between 2013 and 2014. Differences between fall conservation tillage treatments, no-till (NT), AerWay® aerator (AA), and Great Plains Turbo-Till® (GP), and topographic positons, concave, convex and linear were analyzed. Sediment runoff and earthworm biomass were also collected in the fall in 2014. Results indicated a significant increase of soil organic matter (12%-24%), water stable aggregates (78%-98%), phosphorus (43%-76%), and cation exchange capacity (28%-35%) within concave over the convex landscape positions. Soil strength was significantly lower in the field managed with the GP vertical tillage disk compared with the AA field to a depth of 27.5 cm and the NT field to depth of 17.5 cm. Crop residue coverage (percent covered) was more complete in the NT field (12%) and the GP field (3%) compared with the AA field. Suspended sediment runoff was negatively correlated with water-stable aggregates, Ca, and Mg, but positively correlated with earthworm biomass. Extractable nutrients and soil physical properties were also strongly affected by air temperature and precipitation throughout the study period. Characterizing soil properties within topographic positions has potential applications in precision agriculture management, such as reducing excessive fertilization, and identifying areas of increased pollution potential. Evaluation of the tandem effects of conservation tillage tools and topographic position within central Illinois is important in order for the optimization of production and conservation of resources. Physical disturbance from tillage and the transport of sediment from eroded areas to depositional topographic positions are key factors influencing the variability of soil properties, crop productivity, and potential sediment-borne nutrient pollution within individual agricultural fields.

Submitted by SAMANTHA VIEIRA DE ALMEIDA null (samanthaalmeida54@gmail.com) on 2016-04-13T22:49:19Z No. of bitstreams: 1 dissertação versão final definitiva Samantha com ficha e aprov.pdf: 1784365 bytes, checksum: d9a3fcdd8ce18c63106cdef114b6c70c (MD5) / Approved for entry into archive by Juliano Benedito Ferreira (julianoferreira@reitoria.unesp.br) on 2016-04-15T13:42:21Z (GMT) No. of bitstreams: 1 almeida_sv_me_jabo.pdf: 1784365 bytes, checksum: d9a3fcdd8ce18c63106cdef114b6c70c (MD5) / Made available in DSpace on 2016-04-15T13:42:21Z (GMT). No. of bitstreams: 1 almeida_sv_me_jabo.pdf: 1784365 bytes, checksum: d9a3fcdd8ce18c63106cdef114b6c70c (MD5) Previous issue date: 2016-02-19 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Comparou-se entre o transplante de mudas manual (convencional) e o mecanizado, da cultura da alface, em dois sistemas de plantio, sendo eles, sistema de preparo convencional e sistema de plantio direto, avaliando o desempenho operacional em diferentes velocidades de deslocamento do conjunto mecanizado, a viabilidade econômica e os dados agronômicos da cultura. Para o transplante das mudas, foi utilizado o conjunto mecanizado composto por um trator da marca New Holland, modelo TL65E®, 4x2, com potência nominal de 65 cv e uma transplantadora da marca Fedele Mario, modelo MAX® de fabricação italiana. O delineamento experimental utilizado foi o fatorial 2x2+1, sendo que os fatores foram, dois sistemas de plantio (preparo convencional e plantio direto) e duas velocidades de deslocamento (1ª e 2ª marcha), mais a testemunha, onde os canteiros em preparo convencional foram transplantados manualmente. Para a delimitação da área experimental foram separados dentro da propriedade nove canteiros, em que, quatro canteiros de preparo convencional de solo, quatro canteiros de plantio direto e um canteiro transplantado manualmente. No tratamento de plantio direto, quatro canteiros foram preparados com cobertura de palha de milheto (Pennisetum americanum) que foi semeado a lanço e dessecado três meses após a semeadura. Foram analisadas as características: massa fresca, altura da planta, número de folhas e altura do caule da cultura da alface, além do desempenho operacional da máquina e custos operacionais. Todos os tratamentos foram submetidos as médias a uma análise de variância seguida do Teste Tukey a 5% de probabilidade. Os resultados obtidos, demonstraram que a operação de transplante mecanizado da alface mostrou um rendimento operacional 54% maior que a operação de transplante manual. A maior capacidade de campo operacional foi encontrada no sistema de preparo convencional na velocidade mais alta, a qual rendeu mais metros de canteiros por hora em relação aos outros tratamentos. A mão-de-obra confirmou ser o principal e mais caro componente do custo operacional para os dois sistemas de transplante. A produtividade da cultura não sofreu interferência em relação ao comparativo entre todos os tratamentos. / This work has as its aim to do the comparison between the manual and mechanized transplant of lettuce crop, conventional and no-till, evaluated the operational development of the machine and crop agronomic data in different dislocation speeds. The work was done in a farm, in Pardinho-SP County, commercial producer of growers as lettuce, cauliflower, broccoli, cabbage, among others. To do the transplant, it has used the mechanized group composed by TL60E® New Holland 4x2 tractor, 65 nominal power and a Italian Fidele Mario MAX® conveyor. The experimental design was the 2x2+1 factorial, where the variables were two plantation system (conventional and direct) and two dislocation speeds (1st and 2nd gear), plus the testimony where the seedbeds were manually transplanted by conventional prepare. For experimental area delimitation, it were set apart inside property, 9 seedbeds randomly, where, 5 seedbeds were duly prepared with rotated hoe, where 4 of them had the seedlings transplanted with the conveyor and 1 manually. In direct plantation treatment, 4 seedbeds were prepared with millet (Pennisetum americanum) straw cover haul and dried 3 months after sowing. The variables were analyzed: fresh weight, plant height, number of leaves and stalk height in addition to the operational performance of the machine and operating costs. All treatments were submitted the medium to an analysis of variance followed by Tukey test of 5% probability. The results showed that the mechanized transplanting operation showed an operating lettuce yield 54% greater than manual transplantation operation. The largest operational field capacity was found in conventional tillage system at the highest speed, which grossed more meters beds per hour compared to other treatments. The hand labor proved to be the main and most expensive component of the operating cost for the two transplant systems. The crop yield was not affected in relation to the comparison between all treatments.

Submitted by MICHELY DA SILVA ALVES null (michely-alves@hotmail.com) on 2016-04-25T11:54:23Z No. of bitstreams: 1 Michely - Dissertação Final.pdf: 2742202 bytes, checksum: 0308d3f5eca9eabf8eb23b41ea64599c (MD5) / Approved for entry into archive by Felipe Augusto Arakaki (arakaki@reitoria.unesp.br) on 2016-04-27T16:47:45Z (GMT) No. of bitstreams: 1 alves_ms_me_bot.pdf: 2742202 bytes, checksum: 0308d3f5eca9eabf8eb23b41ea64599c (MD5) / Made available in DSpace on 2016-04-27T16:47:45Z (GMT). No. of bitstreams: 1 alves_ms_me_bot.pdf: 2742202 bytes, checksum: 0308d3f5eca9eabf8eb23b41ea64599c (MD5) Previous issue date: 2016-02-24 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / A rotação de culturas em sistema de semeadura direta podem aumentar o estoque de C no solo e reduzir as emissões de gases de efeito estufa, no entanto o emprego de corretivos de solo pode prejudicar esses benefícios. Dentro deste enfoque o trabalho teve como objetivo avaliar a emissão anual de gases de efeito estufa e o estoque de C no sistema solo-planta em função do uso de diferentes corretivos da acidez do solo e de rotações de culturas em sistema de semeadura direta de longa duração. A pesquisa foi realizada, na Fazenda Experimental Lageado, pertencente à Faculdade de Ciências Agronômicas – UNESP, localizada no município de Botucatu (SP), e foi conduzida nos anos agrícolas de 2014/2015. O delineamento estatístico experimental foi em blocos casualizados dispostos em esquema de parcelas subdivididas. As parcelas foram constituídas por quatro sistemas de produção (I. Sistema “Safra consorciada com Forrageira”; II. Sistema “Safra – safrinha”; III. Sistema “Safra – Adubo Verde/Planta de Cobertura”; IV. Sistema “Safra Pousio”) e as subparcelas por duas fontes de corretivos de acidez aplicados em outubro de 2012 e uma testemunha (I – Correção com calcário dolomítico; II – Correção com silicato de cálcio e magnésio; III – Sem correção). As amostragens de gases para a determinação dos fluxos do CO2, N2O e CH4 provenientes do solo foram realizadas após a safra de verão em 2014/2015 e após a de inverno em 2015, em um total de 17 coletas de gases. Foram analisadas as quantidades de palha produzida em cada cultivo e os aportes médios de C e N adicionados ao solo no cultivo de inverno e verão. Foram avaliados também os estoques de C e N do solo nas profundidades de 0-10, 10-20, 20-40 cm, e C e N da biomassa microbiana na profundidade de 0-10 cm. Os resultados foram submetidos à análise de variância (p<0.05) e as médias foram comparadas pelo teste t (p<0.05). As rotações de culturas em Sistema Semeadura Direta e o uso de corretivos não aumentaram os estoques de C orgânico total e de N total no solo, tão pouco da Biomassa Microbiana. Apesar de não contribuir para os estoques no solo, a rotação de culturas com sistemas envolvendo forrageira e adubo verde resultaram em menores emissões de CO2 especialmente na safra. Por outro lado, no cultivo de outono-inverno, o aporte de resíduos sobre o solo não reduziu as emissões, especialmente de N2O. A correção do solo não aumentou as emissões acumuladas de CO2, porém, na comparação entre os corretivos, a maior emissão de CO2 ocorreu com o uso de silicato. Os sistemas de produção com uso de forrageira e adubo verde no inverno, e o uso de corretivos da acidez, principalmente o silicato, aumentou a produtividade de grãos de milho por unidade de massa de carbono equivalente emitido para a atmosfera. / Crop rotation in no tillage can increase the stock of C in the soil and reduce emissions of greenhouse gases, though the use of soil amendments can undermine these benefits. Within this approach the work aimed to evaluate the annual emission of greenhouse gases and carbon storage in the soil-plant system due to the use of different corrective of soil acidity and crop rotations in long-tillage system duration. The survey was conducted in the Experimental Farm Lageado, belonging to the Faculty of Agricultural Sciences - UNESP, located in Botucatu (SP), and was conducted in the agricultural year 2014/2015. The plots consisted of four production systems (I. System "Safra intercropped with forage"; II System "Safra - offseason."; III System "Safra - Green manure / cover plant."; IV System "Safra Fallow." ) and the subplots by two sources of acidity corrective applied in October 2012 and a control (I - Correction with dolomitic lime II - Correction with calcium and magnesium silicate III - No correction). The gas samples for the determination of CO2 flows, N2O and CH4 from soil were performed after summer season 2014/2015 and further in the winter in 2015. The quantities of straw produced in each culture medium and supply of C and N added to the soil in winter and summer crops were analyzed. They also evaluated the stocks of C and N soil at 0-10, 10-20, 20-40 cm, and C and N microbial biomass at a depth of 0-10 cm. The results were submitted to analysis of variance (p <0.05) and the means were compared using the t test (p <0.05). Crop rotations System direct sowing and the use of lime did not increase the total organic carbon stocks and total N in the soil, as little of Microbial Biomass. Although not contributed to the stocks in the soil, crop rotation with systems involving forage and green manure resulted in lower CO2 emissions especially in the harvest. On the other hand, in the autumnwinter, the residue inputs on the ground did not reduce emissions, especially N2O. The soil remediation did not increase the accumulation of CO2, however, in the comparison between the correctives, the most CO2 emission occurred with the use of silicate. The production systems with use of fodder and green manure in winter, and the use of limestone, mainly silicate, increased productivity of corn grain per unit mass of carbon equivalent emitted into the atmosphere.

Submitted by MARCELO BOAMORTE RAVELI null (m_boamorte@hotmail.com) on 2016-05-02T14:30:57Z No. of bitstreams: 1 ravelli_mb_dr_abr.pdf: 2426603 bytes, checksum: 9cf7fdbd7d08b14678da4d6ae03b055c (MD5) / Approved for entry into archive by Felipe Augusto Arakaki (arakaki@reitoria.unesp.br) on 2016-05-04T14:54:36Z (GMT) No. of bitstreams: 1 ravelli_mb_dr_jabo.pdf: 2426603 bytes, checksum: 9cf7fdbd7d08b14678da4d6ae03b055c (MD5) / Made available in DSpace on 2016-05-04T14:54:36Z (GMT). No. of bitstreams: 1 ravelli_mb_dr_jabo.pdf: 2426603 bytes, checksum: 9cf7fdbd7d08b14678da4d6ae03b055c (MD5) Previous issue date: 2016-04-05 / Espécies forrageiras para o Sistema Plantio Direto são de grande interesse técnico e econômico, pois se apresentam como opções para a formação de pastagens e adubação verde conjuntamente com a rotação de culturas em uma mesma área e mesma estação. O objetivo do experimento foi obter informações quanto às melhores alternativas para o Sistema Plantio Direto em Jaboticabal/SP, região de clima subtropical úmido com estiagem no inverno. O experimento foi desenvolvido em Latossolo Vermelho Eutroférrico, no período de 2011 a 2014. Avaliou-se as culturas do milho e soja em Sistema Plantio Direto, em diferentes manejos de culturas de cobertura do solo, bem como a rotação de culturas. As culturas de cobertura utilizadas foram: milheto e braquiária (1° ano) antecedendo o milho; o milheto (2° ano) antecedendo a soja; e três espécies de braquiárias (3° ano) antecedendo o milho. Analisaram-se parâmetros relacionados ao solo, como teor de água, densidade e resistência à penetração; nas plantas, emergência, estandes e produtividade e na operação de semeadura, distribuição longitudinal de plântulas e demanda energética. No primeiro ano houve maior consumo horário para o manejo com rolo-facas, e o consumo operacional para a cobertura com a cultura da braquiária; a semeadura de milho com espaçamento entrelinhas de 0,90 m demandou menor força, potência e consumo, aliado à mesma produtividade do espaçamento de 0,45 m. O segundo ano do experimento foi caracterizado pela produção de matéria seca abaixo da média; para os diferentes manejos sobre a cobertura do milheto houve decomposição homogênea entre os manejos nas áreas experimentais, não havendo influencia pelos tratamentos realizados. No terceiro ano onde foram testadas diferentes espécies de braquiárias, a B. ruzizienses se destacou em formação de matéria seca, afetando a qualidade da distribuição das sementes de milho na semeadura, aumentando as falhas e espaçamentos duplos, porém houve maior produtividade final; os tratamentos com diferentes velocidades mostraram que menores velocidade garantem melhor qualidade na operação de semeadura, o que é refletido diretamente na produtividade da área. Recomenda-se o sistema plantio direto para a região de Jaboticabal/SP do ponto de vista de produtividade das culturas de verão e conservação dos recursos naturais. / Forage species for no-tillage system represents great technical and economic interests, as they are presented as options for cattle pasture and green fertilizer along with crop rotation in the same area and weather station. The general object of the experiment was to obtain information on the best alternatives for the no-tillage system in Jaboticabal / SP, of humid subtropical climate region with drought in the winter. The experiment was conducted over Oxisoil, during the period 2011 to 2014. The objective was to evaluate corn and soybean crops under no-tillage technique with different managements and rotation of cover crops. Cover crops were: millet and brachiaria (1st year) preceding corn; millet (2nd year) preceding soybean ; and three species of Brachiaria (3rd year) preceding corn. It was analyzed parameters related to soil, like water content, density and mechanical resistance to penetration; for plants, emergency, stands and productivity; and for sowing operation, longitudinal distribution of seedlings and energy demand. In the first year there was a higher consumption for handling cover crops with roll-choper, and also for parameter operating consumption over the culture of brachiaria; corn planting with row spacing of 0.90 m demanded lower traction force, power and consumption, but combined with the same productivity of the reduced spacing (0.45 m). The second year of the experiment was characterized by dry matter production below average; the different managements on millet cover was homogeneous breakdown among managements in the experimental areas, with no influence by the treatments performed. In the third year, B. ruzizienses stood out for dry matter formation, affecting the quality of maize seed distribution at sowing, increasing plant failures and double spacing, but there was a higher end productivity; treatments with different speeds showed that lower speed guarantee best quality in sowing operation, which is reflected directly in the productivity of the area. We recommend no-tillage system for the region of Jaboticabal/SP from the standpoint of productivity of summer crops and conservation of natural resources.

Conselho Nacional de Desenvolvimento Científico e Tecnológico / The present work was conducted to evaluate the operational conditions of a no tillage system for maize culture. Two different speeds was considered, 4.1 km/h and 7.2 km/h in three different depths of planting, 3, 5 and 7 cm. To consider the field conditions the soil moisture and the soil resistance to penetration was determined. The experiment was mounted in randomized blocks with four replications. The longitudinal seed spacing, effective deposition depth and the wheel sliding of planter were measured. The analysis of variance didn t indicate no significant differences in longitudinal seed spacing in relation of different depths and speeds. It was is expected in function of feeder mechanism characteristics of seeder. In function of the irregularity presented in the longitudinal spacing, the influence of the wheel sliding was considered in feeder mechanism system. The consideration of wheel sliding for correction in seed spacing was not enough to guarantee an adjusted regulation. The present work shows the necessity of more studies to identify other factors not yet studied in feeder mechanism functionality for seed distribution. / O presente trabalho buscou avaliar as condições de operação de uma semeadora/adubadora de plantio direto para a cultura de milho. Foram consideradas duas velocidades, 4,1 km/h e 7,2 km/h em três diferentes profundidades de semeadura, 3, 5 e 7 cm. Para considerar as condições de solo foi feito o levantamento de umidade e a resistência do solo à penetração. O experimento foi montado em blocos ao acaso com quatro repetições. Foram determinados os espaçamentos longitudinais dentro da linha de plantio e profundidades efetivas de deposição das sementes e os coeficientes de deslizamento da roda motriz da semeadora. A análise de variância indicou que não houve diferenças significativas para os espaçamentos longitudinais em função das diferentes profundidades e velocidades. Esse comportamento era esperado em função das características do sistema dosador de sementes. Em função da irregularidade apresentada nos espaçamentos longitudinais, foi considerada a influência do deslizamento da roda motriz sobre o sistema dosador. A adoção do coeficiente de deslizamento para correção dos espaçamentos esperados não foi suficiente para garantir uma regulagem adequada, O presente trabalho mostra a necessidade de mais estudos para identificar outros fatores ainda não estudados no funcionamento do mecanismo de distribuição de sementes.

Made available in DSpace on 2014-06-11T19:31:33Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-06-01Bitstream added on 2014-06-13T19:41:52Z : No. of bitstreams: 1 bertolini_ev_dr_botfca.pdf: 976816 bytes, checksum: 33d964ee6a502afaba9948bd767da98f (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Cada sistema de manejo do solo é trabalhado de maneira própria, alterando de forma diferenciada as propriedades químicas, físicas e biológicas do solo, podendo requerer modificações nas recomendações e no manejo da adubação. Com o objetivo de avaliar o efeito da antecipação da adubação de semeadura, de dois sistemas de manejo do solo e dois espaçamentos entrelinhas no desempenho da cultura do milho, foi realizado este estudo. O experimento foi instalado e conduzido na Fazenda Experimental Lageado, pertencente à Faculdade de Ciências Agronômicas (FCA) da Universidade Estadual Paulista (UNESP), Campus de Botucatu, nos anos agrícolas de 2005/2006 e 2006/2007, em Nitossolo Vermelho Distroférrico. O delineamento experimental utilizado foi de blocos ao acaso com parcelas subsubdivididas e quatro repetições. As parcelas foram constituídas pelos sistemas de manejo do solo (plantio direto e preparo reduzido, caracterizado pela escarificação do solo por meio de equipamento provido de disco de corte da palhada e rolo nivelador/destorroador, trabalhando na profundidade entre 25 e 30 cm), as subparcelas pelas formas de adubação (adubação de pré-semeadura realizada na superfície do solo em área total antes da semeadura do milho e adubação convencional) e as subsubparcelas pelos espaçamentos entrelinhas (90 e 45 cm), totalizando 8 tratamentos. Os resultados obtidos foram submetidos ao teste de Tukey a 5% de probabilidade para comparar as médias entre os sistemas de manejo do solo, as formas de adubação, os espaçamentos entrelinhas e os desdobramentos das interações entre esses três fatores. As análises estatísticas demonstraram que o sistema plantio direto apresentou maior densidade do solo e resistência mecânica do solo à penetração, quando comparado ao preparo reduzido. Na operação de adubação de pré-semeadura os sistemas de manejo do solo... / Each soil tillage system is worked in proper way, modifying of differentiated form the chemical, physical and biological soil properties, and may require adaptations of fertilization recommendations and management. This study was conducted to evaluate the effect of sowing fertilization anticipation, two soil tillage systems and two row spacing on performance of the corn crop. The experiment was carried out at the “Faculdade de Ciências Agronômicas” (FCA), “Universidade Estadual Paulista” (UNESP), Botucatu-SP campus, from October 2005 to May 2007, in a Dystric Nitosol (FAO, 1974). The experimental design was in randomized blocks with split-split-plots and four repetitions. The main plots consisted of two soil tillage systems (no-tillage and reduced tillage with chisel plow with cut disk and planning roll, working at 25 to 30 cm deep), the split-plots of fertilizer application methods (surface fertilizer application before corn sowing and fertilizer application conventional) and split-split-plots of row spacings (0.90 m and 0.45 m), totalizing 8 treatments. Obtained results were analyzed by Tukey test at 5% of probability for comparing averages. Statistical analysis showed that no-tillage system had higher density as well as mechanical soil resistance to penetration, when compared to reduced tillage. For fertilizer application before corn sowing the soil tillage systems did not influence the traction force, bar power demanded, effective field capacity, demanded time, energy specific consumption and hourly fuel consumption; the reduced tillage showed higher area fuel consumption. For corn sowing it was observed that no-tillage system showed lower traction force, bar power demanded, energy specific consumption, hourly and area consumption of fuel. The 0.45 m row spacing showed higher traction force, bar power demanded, energy specific consumption... (Complete abstract click electronic access below)

Made available in DSpace on 2014-06-11T19:31:33Z (GMT). No. of bitstreams: 0 Previous issue date: 2012-09-03Bitstream added on 2014-06-13T19:20:43Z : No. of bitstreams: 1 santos_ajm_dr_botfca.pdf: 682394 bytes, checksum: caad3657a44a0032aa38cff4fd7f9846 (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Universidade Estadual Paulista (UNESP) / No sistema de produção de gramas a compactação nas camadas superficiais do solo, proporcionada pela passagem de um rolo compactador no momento da colheita, é favorável para facilitar o corte dos tapetes e obtenção de tapetes com boas características para a venda, porém esta compactação reflete no desenvolvimento da grama do próximo ciclo, uma vez que afeta as características físicas do solo. Para minimizar os efeitos desta compactação são utilizados, por alguns produtores, equipamentos de preparo do solo. Estes equipamentos devem mobilizar o solo de forma superficial de modo a não causar rugosidade excessiva, que pode prejudicar a qualidade do tapete formado. Dessa forma, objetivou-se no presente trabalho verificar os efeitos dos manejos mecanizados nas propriedades físicas do solo e na produção de tapetes de grama esmeralda. O delineamento experimental utilizado foi o de blocos ao acaso, com quatro repetições. Os tratamentos foram constituídos por cinco sequências de preparo do solo: controle (sem o uso de equipamentos); uma passada da estrelinha (1E); duas passadas da estrelinha (2E); uma passada do escarificador (1H) e uma passada do escarificador e uma da estrelinha (1H + 1E). Os tratamentos que receberam a passagem de 2E e 1H + 1E proporcionaram maior velocidade de infiltração básica de água no solo e maior taxa de cobertura do solo pela grama, avaliada aos 330 DAC. Nos tratamentos 2E e 1H + 1E houve redução da resistência mecânica do solo a penetração na camada de 0,00-0,05 m. Na camada de 0,05-0,10 m houve redução da resistência apenas quando utilizado o escarificador, com ou sem a passagem da estrelinha.Para a massa seca de folhas + caules não houve influência dos tratamentos. Os tratamentos com 2E, 1H e 1H + 1E proporcionaram maior... / In the production system of grasses, surface soil compaction due to the use of compactors at harvesting favors and facilitates grass sod cutting and grass sods with good sales characteristics; however, compacting influences the development of the next grass cycle because it affects the soil physical characteristics. To minimize the effects of compacting, some producers use soil preparation equipment that raises the soil on the surface but does not cause excessive roughness which may harm the quality of the formed sod. Thus, this paper aimed to verify the effects of mechanized managements on the physical properties of the soil and on the production of zoysiagrass sods. The experimental design had random plots and four replications. The treatments consisted of five sequences of soil preparation: control (without the use of equipment); coulter blade disc harrow used once (1CB), coulter blade disc harrow used twice (2CB), surface chisel used once (1C), surface chisel and coulter blade disc harrow used once (1C + 1CB). The treatments with 2CB and 1C + 1CB provided greater basic water infiltration speed in the soil and higher rate of soil covering by the grass when evaluated at 330 days. In treatments 2CB and 1C + 1CB, there was a reduction of the mechanical resistance of the soil to penetration in the 0.00-0.05 m depth layer. In the 0.05-0.10 m depth layer, there was a decrease of resistance only when chisel was used, with or without rotary tiller use. For dry matter mass+stems, there was no influence of the treatments. The treatments with 2CB, 1C and 1C + 1CB provided a greater development of rhizomes+stolons+roots of... (Complete abstract click electronic access below)