Antonio Gabriel Filho

Desempenho de trator agrícola em três superfícies de solo e quatro velocidades de deslocamento

The aim of this work was to evaluate tractor performance in soil with three different surfaces: firm soil without covering, mobilized soil, and firm soil with vegetal residue of corn and braquiaria, for four forward speeds. The experiment was accomplished in three plots determined by the soil conditions. In each plot four treatments were composed by the forward speed obtained by the changes of the tractor gear. Six repetitions were used in each plot, totaling 72 experimental units, combination of the traction, slip of the rear and front wheels, forward speed and fuel consumption. The values of the tractor performance obtained led to the conclusion that in the firm soil without vegetable covering the tractor performance was better, followed by the soil with the firm surface and covered with corn straw and braquiaria and finally the mobilized soil. The best tractor performance was obtained in the C1 gear that supplied the forward speed of 6 km h-1.

PRAPRAG: software para planejamento racional de máquinas agrícolas

The software PRAPRAG is a tool used for choosing agricultural machines and implements that present the lowest cost per area or produced amount, as well as, to it makes the machines acquisition planning for the agricultural property, from both technical and economical points of view. It was used the programming language Borland Delphi 3.0. From the machine and implement handouts, it was created a database where the user can register and modify their characteristics of use. The software showed to be a useful and friendly tool. The software provides high speed, safety and reliability for the productive and economical process of the properties, at the selection and acquisition of agricultural systems, as well as for the determination of costs with the used labor.

Preparo convencional e cultivo mínimo do solo na cultura de mandioca em condições de adubação verde com ervilhaca e aveia preta

Soil tillage for cassava cropping is tradicionally executed by a number of rowing and tillage which may result in alteration of the physical and chemical soil properties. The use of plants for green cover manure and the use of minimum tillage may contribute to reduction of soil erosion and to facilitate manual harvest. An experiment in eutrophic Oxisol, located in Marechal Cândido Rondon country state of Parana, Brazil, was carried out to collect information on the physical soil properties, harvest effort strength and cassava productivity. Experimental design was composed by eight treatments with four repetitions on a 2x4 factorial. Were used two soil tillage (conventional and minimum) and four soil cover types: common vetch (Vicia sativa), black oat (Avena strigosa), common vetch plus black oat and bare soil. The results showed that soil density and resistance to penetration in the 0-10cm layer were higher under conventional than under minimum tillage. There were no differences for cassava harvest effort and cassava productivity between soil tillage treatments as well as among types of soil cover. No significant interaction was detected also. It is hypotesized that the results obtained are due to the fact that soil used did not have compaction, the soil had a high degree of natural fertility and there was no water stress during the experiment. Consequenthy, minimum tillage may substitute conventional tillage and reduce costs for cassava cropping.Aluno de Graduacao, Curso de Agronomia, bolsista de iniciacao cientifica PIBIC-CNPq, UNIOESTE.RESUMONa cultura da mandioca, o preparo do solo etradicionalmente realizado com uma aracao e duas gradagens, oque pode causar compactacao e erosao do solo e diminuicao daprodutividade. O uso de plantas de cobertura do solo comoadubacao verde e o preparo do solo atraves do metodo de cultivominimo podem contribuir na diminuicao do processo erosivo dosolo e facilitar a colheita m anual. Implantou-se o experimento emLatossolo Roxo eutrofico em Marechal Cândido Rondon (PR),visando a obtencao de dados sobre alteracoes em algumaspropriedades fisicas do solo, no esforco de arranquio e naprodutividade de raizes de mandioca. O delineamentoexperimental foi blocos ao acaso com oito tratamentos e quatrorepeticoes, em esquema fatorial do tipo 2x4, ou seja, doissistemas de preparo do solo (cultivo minimo e preparoconvencional) e quatro tipos de cobertura vegetal do solo (aveia,ervilhaca, aveia em consorcio com ervilhaca e solo em pousio).Os resultados mostraram que a densidade do solo e a resistenciado solo a penetracao, na camada de 0 a 10cm, foram maiores nasareas de preparo convencional do solo. Nao houve diferenca noesforco de arranquio e na produtividade de raizes de mandioca ecultivada com preparo convencional e cultivo minimo do solo,tampouco das plantas de cobertura que antecederam o cultivo damandioca Isso, possivelmente, ocorreu porque o soloapresentava-se com boa estrutura, com alta fertilidade natural enao houve deficiencia hidrica na regiao durante o periodo deavaliacao. Portanto, o cultivo minimo pode substituir o preparoconvencional do solo, nessas condicoes, diminuindo, assim, oscustos de implantacao da lavoura na cultura da mandioca,reduzindo significamente os impactos ambientais causados pelaerosao hidrica.Palavras-chave: mandioca, preparo do solo, plantas de cobertu-ra do solo, cultivo minimo.SUMMARYSoil tillage for cassava cropping is tradicionallyexecuted by a number of rowing and tillage which may result inalteration of the physical and chemical soil properties. The use ofplants for green cover manure and the use of minimum tillagemay contribute to reduction of soil erosion and to facilitatemanual harvest. An experiment in eutrophic Oxisol, located inMarechal Cândido Rondon country state of Parana, Brazil, wascarried out to collect information on the physical soil properties,harvest effort strength and cassava productivity. Experimentaldesign was composed by eight treatments with four repetitions ona 2x4 factorial. Were used two soil tillage (conventional andminimum) and four soil cover types: common vetch ( Vicia sativa),black oat (Avena strigosa), common vetch plus black oat andbare soil. The results showed that soil density and resistance topenetration in the 0-10cm layer were higher under conventionalthan under minimum tillage. There were no differences forcassava harvest effort and cassava productivity between soiltillage treatments as well as among types of soil cover. Nosignificant interaction was detected also. It is hypotesized that theresults obtained are due to the fact that soil used did not havecompaction, the soil had a high degree of natural fertility andthere was no water stress during the experiment. Consequenthy,minimum tillage may substitute conventional tillage and reducecosts for cassava cropping.Key words: cassava, minimum tillage, green manure.

Força de tração e potência de uma semeadora em duas velocidades de deslocamento e duas profundidades de deposição de sementes

Traction and power required by a seed drill with 14 holes was evaluated in the oat (Avena strigosa L) seeding. The experiment was carried out in a Haplortox, in an area with mean slope of 0.03 m m-1. The experimental design consisted of four treatments (two seed deposition depths and two displacement speeds) with four repetitions, totaling sixteen experimental plots of 4 x 50 m (200 m2), in no tillage system on corn crop residue. It was concluded that the increase of the seeding depth of 1.97 cm to 2.68 cm, the draft requirement increased from 3.78 to 5.51 kN. The speed increase from 5.24 to 7.09 km h-1, caused an increase of 6,90% in the traction force of the drawbar.

Profundidade e espaçamento da mandioca no plantio direto na palha

The experiment was conducted in eutrophic Oxisol soil in Marechal Cândido Rondon, PR, Brazil. It consisted of planting cassava in a factorial design. Factors included two row design: simple (1.00 x 0.60m), double rank (1.50 x 0.50 x 0.60m); and three planting depths (0.05, 0.10 and 0.15m). Planting was accomplished in no-tillage system over oat straw. Measured variables 17 months after planting included: stalk mean diameter; damping-off index; resistence to manual harvesting; root starch concentration; and productivity of root and starch. The results indicated that damping-off index was lower at 0.15m planting depth. However, cassava planted at the 0.15m depth demanded the higest labor for harvesting and the lowest root and starch productivities. The best root and starch productivity was achiered at the 0.10m soil depth.

Influência da altura das garras dos pneus de um trator em área de plantio direto

This work was carried out to evaluate the performance of a farm tractor fitted with two sets of tires with high lugs and another set of tires with tallow lugs in straw without tillage (corn straw). The travel speeds used were approximately 4, 5, 6 and 7 km h-1 and a constant pulling force of 25 kN was fixed. Tractor traction, forward speed, slip and consumption of fuel were measured and drawbar power, the ratio between the consumption and power and traction coefficient were calculated. It was observed that the tractor performance was similar to high and low lug tire conditions, in an area covered with corn straw.

Distribuição de palha por colhedoras autopropelidas na colheita da soja

The difficulty of getting a uniform residues distribution, in the width of the combine cutting ban, have been observed in crop fields. The objective of this work was to evaluate the uniformity of straw distribution for combines harvesting soybean. It was appraised nine combines in the operation conditions and adjustment that they were being used by the operator. The Coefficient of Variation (CV) was used for comparison of the machines and the evaluation of the distribution uniformity, and had accomplished a multivariate analysis to evaluate the similarity among the combines in function of the coefficient of variation, humidity of the straw and width of the cut platform. All the combines had presented a disuniform straw distribution, resulting in bands, with raised straw concentration in the combine central part and little in the extremities, independently of the width of the cut platform. But a combine presented distribution next to the ideal, for also possessing a delivering system for the straw proceeding from the bolters. One evidenced that the deriving straw of the combine bolters can be the responsible for the formation of bands with raised amounts of straw in the combine center, independently of the machine size.

Differences between convencional and minimum tillage soil preparation for cassava cropping with Vicia sativa and Avena strigosa green manure

Soil tillage for cassava cropping is tradicionally executed by a number of rowing and tillage which may result in alteration of the physical and chemical soil properties. The use of plants for green cover manure and the use of minimum tillage may contribute to reduction of soil erosion and to facilitate manual harvest. An experiment in eutrophic Oxisol, located in Marechal Cândido Rondon country state of Parana, Brazil, was carried out to collect information on the physical soil properties, harvest effort strength and cassava productivity. Experimental design was composed by eight treatments with four repetitions on a 2x4 factorial. Were used two soil tillage (conventional and minimum) and four soil cover types: common vetch (Vicia sativa), black oat (Avena strigosa), common vetch plus black oat and bare soil. The results showed that soil density and resistance to penetration in the 0-10cm layer were higher under conventional than under minimum tillage. There were no differences for cassava harvest effort and cassava productivity between soil tillage treatments as well as among types of soil cover. No significant interaction was detected also. It is hypotesized that the results obtained are due to the fact that soil used did not have compaction, the soil had a high degree of natural fertility and there was no water stress during the experiment. Consequenthy, minimum tillage may substitute conventional tillage and reduce costs for cassava cropping.Aluno de Graduacao, Curso de Agronomia, bolsista de iniciacao cientifica PIBIC-CNPq, UNIOESTE.RESUMONa cultura da mandioca, o preparo do solo etradicionalmente realizado com uma aracao e duas gradagens, oque pode causar compactacao e erosao do solo e diminuicao daprodutividade. O uso de plantas de cobertura do solo comoadubacao verde e o preparo do solo atraves do metodo de cultivominimo podem contribuir na diminuicao do processo erosivo dosolo e facilitar a colheita m anual. Implantou-se o experimento emLatossolo Roxo eutrofico em Marechal Cândido Rondon (PR),visando a obtencao de dados sobre alteracoes em algumaspropriedades fisicas do solo, no esforco de arranquio e naprodutividade de raizes de mandioca. O delineamentoexperimental foi blocos ao acaso com oito tratamentos e quatrorepeticoes, em esquema fatorial do tipo 2x4, ou seja, doissistemas de preparo do solo (cultivo minimo e preparoconvencional) e quatro tipos de cobertura vegetal do solo (aveia,ervilhaca, aveia em consorcio com ervilhaca e solo em pousio).Os resultados mostraram que a densidade do solo e a resistenciado solo a penetracao, na camada de 0 a 10cm, foram maiores nasareas de preparo convencional do solo. Nao houve diferenca noesforco de arranquio e na produtividade de raizes de mandioca ecultivada com preparo convencional e cultivo minimo do solo,tampouco das plantas de cobertura que antecederam o cultivo damandioca Isso, possivelmente, ocorreu porque o soloapresentava-se com boa estrutura, com alta fertilidade natural enao houve deficiencia hidrica na regiao durante o periodo deavaliacao. Portanto, o cultivo minimo pode substituir o preparoconvencional do solo, nessas condicoes, diminuindo, assim, oscustos de implantacao da lavoura na cultura da mandioca,reduzindo significamente os impactos ambientais causados pelaerosao hidrica.Palavras-chave: mandioca, preparo do solo, plantas de cobertu-ra do solo, cultivo minimo.SUMMARYSoil tillage for cassava cropping is tradicionallyexecuted by a number of rowing and tillage which may result inalteration of the physical and chemical soil properties. The use ofplants for green cover manure and the use of minimum tillagemay contribute to reduction of soil erosion and to facilitatemanual harvest. An experiment in eutrophic Oxisol, located inMarechal Cândido Rondon country state of Parana, Brazil, wascarried out to collect information on the physical soil properties,harvest effort strength and cassava productivity. Experimentaldesign was composed by eight treatments with four repetitions ona 2x4 factorial. Were used two soil tillage (conventional andminimum) and four soil cover types: common vetch ( Vicia sativa),black oat (Avena strigosa), common vetch plus black oat andbare soil. The results showed that soil density and resistance topenetration in the 0-10cm layer were higher under conventionalthan under minimum tillage. There were no differences forcassava harvest effort and cassava productivity between soiltillage treatments as well as among types of soil cover. Nosignificant interaction was detected also. It is hypotesized that theresults obtained are due to the fact that soil used did not havecompaction, the soil had a high degree of natural fertility andthere was no water stress during the experiment. Consequenthy,minimum tillage may substitute conventional tillage and reducecosts for cassava cropping.Key words: cassava, minimum tillage, green manure.

Evaluation of alternative containers to determining the working width of fertilizer spreaders

Os ensaios de largura de trabalho e uniformidade de distribuicao sao de dificil execucao para o agricultor por exigirem equipamentos, recursos e metodos complexos. Portanto, este trabalho teve como objetivo avaliar coletores alternativos para tornar mais acessivel a regulagem e a avaliacao de distribuidores de fertilizantes solidos a lanco. Foram utilizados quatro diferentes conjuntos de coletores: i) coletores construidos segundo a norma ISO 5690/1; ii) coletores de polietileno (bandejas plasticas) com tela de sombreamento para evitar o ricochete de material; iii) coletores formados por caixas de leite longa vida, e iv) coletores formados por vasos de polietileno (numero 3,5). Tambem foram utilizados tres diferentes distribuidores para as avaliacoes. Os coletores alternativos apresentaram maior retencao de particulas que os coletores normatizados. A largura efetiva de trabalho obtida para os coeficientes de variacao de 12,5; 15; 17,5 e 20% variou entre os coletores nos diferentes percursos. O coletor que mais se assemelhou a norma foram os vasos de polietileno. Constatou-se que a altura dos coletores foi mais importante para sua eficiencia do que a sua area de coleta.

Influência do controle manual e mecânico de plantas daninhas na produtividade de mandioca cultivada no sistema de plantio direto na palha

Cassava cultivation is traditionally done with conventional soil preparation. Other techniques such as no-tillage and minimum tillage are currently being adopted. Differences in weed development have been recorded with conventional tillage as compared to that with no-tillage. Manual and mechanical treatments accomplished 30 and 60 days after planting of cassava cultivated under conventional no-tillage are evaluated. Data on yield, effort in manual harvesting and starch concentration were collected. Results indicated that, in the absence of weeds, yield (25759 kg ha -1 ) was not statistically different from that obtained with manual weeding 60 days after planting (20952 kg ha -1 ). Manual or mechanical weeding 30 days after planting did not yield satisfactory. On the contrary, it increased cropping labor and decreased root starch concentration due to weed competition