ABSTRACT: Sowing occurs in agricultural areas with irregular relief, influencing the quality of seed and fertilizer distribution. The aim of this study was to analyze the performance of different fertilizer metering mechanisms of planters as a function of longitudinal inclination. The experimental design was a completely randomized design with five treatments and six replications. Treatments consisted of five longitudinal inclinations to the metering mechanism (−10, −5, 0, 5, and 10 degrees). The mass of fertilizer collected per minute was considered as a replication. We worked with two types of fertilizers: a mixture of granules and powder. Metering mechanisms used were a horizontal toothed rotor, helical without flow restrictor, helical with lateral overflow, and helical with longitudinal overflow. The longitudinal inclination of ±10° in relation to the leveling altered the metered amount of both fertilizers used in all metering mechanisms. The helical with lateral overflow was the metering mechanism that obtained the smallest amount variation of fertilizer distributed in the different longitudinal inclinations, followed by the helical with longitudinal overflow, horizontal toothed rotor, and helical without flow restrictor.

ABSTRACT The aim of this study was to analyze the influence of space between the base and intermediate base on quality of seed distribution with a horizontal seed plate. The experiment was carried out in 2012 at the Laboratory of Agricultural Mechanization of the State University of Ponta Grossa - PR, Brazil, using a sowing simulation device. The experimental design was completely randomized design with four treatments and seven replications. Treatments consisted of spaces (0, 1, 2, and 3 mm) between the base and intermediate base. Replications were defined by 250 spacing between seeds. Corn (Zea mays L.), soybean (Glycine max L. Merrill), and sorghum (Sorghum bicolor Moench) seeds were tested. The analyzed variables were faulty, multiple and acceptable spacing. By increasing the space between base and intermediate base, quality of seed distribution was reduced for all species.

Resumo Os sistemas de navegação por posicionamento global (GPS) estão cada vez mais presentes no campo, prometendo diminuir os custos operacionais do agricultor. O objetivo deste trabalho foi avaliar o tempo de manobra durante a operação de semeadura da soja sem e com sistema de navegação. O delineamento experimental foi inteiramente aleatorizado, com dois tratamentos e doze repetições. Os tratamentos consistiram no tempo das manobras feitas de modo convencional e utilizando-se do sistema de navegação por GPS acoplado num piloto automático. Avaliaram-se o tempo de manobra e o retorno econômico. As manobras realizadas com auxílio do sistema de navegação foram, em média, 49% mais rápidas do que as manobras realizadas de forma convencional. Houve economia de R$ 4,15 por hectare, em áreas com comprimento médio das passadas de 800 metros. No caso de áreas menores, com comprimento de 50 metros, esta economia chegou a R$ 19,90 por hectare. Concluiu-se que o uso de sistema de navegação por satélites, em conjunto com piloto automático, pode gerar economia significativa de tempo e no custo operacional da semeadura.

ABSTRACT GPS navigation systems have been increasingly found in farming activities, promising lower farmer operational costs. Therefore, this research focused to evaluate the maneuvering time during soybean sowing. The experiment was set in an entirely randomized design with two treatments and twelve replications. The treatments consisted of recording maneuver time spent in conventional sowing and with a GPS navigation system coupled to an autopilot. We evaluated the operation time and the economic return. The maneuvers performed with the aid of navigation system were, on average, 49% faster than those carried by conventional system. We observed a cost saving of R$ 4.15 per hectare in areas with 800-m long lines. Moreover, areas with shorter lines (50 meters), such saving reached a value of R$ 19.90 per hectare. Thus, the use of satellite navigation system combined with an autopilot device can generate significant saving in time and operational costs in soybean cropping.

Com a crescente demanda por óleos para a produção de biocombustíveis, espécies que apresentem elevado conteúdo de óleo, como o pinhão-manso (Jatropha curcas L.), são alternativas importantes, frente às opções tradicionais. Tendo em vista que o florescimento se distribui ao longo do ciclo de desenvolvimento da cultura do pinhão-manso objetivou-se, com este trabalho, determinar a época de colheita em dias após o florescimento, adequada para maximização do rendimento de óleo e da qualidade fisiológica de sementes. Em duas safras agrícolas, 2010/2011 (Ano 1) e 2011/2012 (Ano 2) foram colhidos, no município de Paranavaí (PR), frutos de pinhão-manso, em cinco épocas, determinadas por dias após o florescimento: 30, 45, 60, 75 e 90. Em delineamento inteiramente aleatorizado, em esquema de parcelas subdivididas, foram determinados o conteúdo de água, a massa de matéria seca, lipídios totais, emergência em areia e o índice de velocidade de emergência. Pelo comportamento das variáveis as colheitas devem ser realizadas a partir de setenta e cinco dias após o florescimento.

With the increasing demand for oils for biofuel production, species with high oil content, like physic nut (Jatropha curcas L.), are important alternatives in the face of traditional options. Considering that flowering is distributed throughout the development cycle of physic nut crop, the aim of this work was to determine the harvest time, in days after flowering, appropriate to maximize oil yield and physiological quality of seed. In two growing seasons, 2010/2011 (Year 1) and 2011/2012 (Year 2), at Paranavaí in the State of Paraná. Physic nut fruits were harvested at five times, determined by days after flowering: 30, 45, 60, 75 e 90. In completely randomized design, in a split-plot design the water content, dry matter, total lipids, seedling emergence in sand and speed of emergence-index were determined. By the behavior of the variables, harvests should be performed from seventy-five days after flowering.

Dentre os estudos que visam a incrementar os rendimentos da cultura da soja, podem-se destacar aqueles relacionados ao processo de semeadura. Devido ao fato de a soja apresentar emergência epígea, torna-se difícil determinar a profundidade real de semeadura. O objetivo deste trabalho foi identificar indicador que possibilite a mensuração da profundidade de deposição de sementes de soja. Foram realizados dois ensaios em casa de vegetação. O ensaio 1 visou a identificar possíveis estruturas indicativas da profundidade de semeadura, em um solo de textura média, característico da região dos Campos Gerais, no Estado do Paraná, Brasil. As sementes da cultivar Spring NK 8350 foram depositadas em cinco profundidades teóricas (1; 2; 3; 4 e 5 cm). Após a emergência das plântulas, foram determinadas a profundidade da zona de diferenciação e a profundidade da curva na raiz. O ensaio 2 consistiu na validação dos indicadores sugeridos no ensaio 1, em dois tipos de solo, um de textura média e outro de textura argilosa. A cultivar utilizada no ensaio 2 foi a BRS 232. As duas metodologias mostraram alta correlação com a profundidade teórica de deposição. Embora tenham apresentado coeficientes de correlação próximos, a zona de diferenciação foi a referência mais eficiente, com menor grau de superestimativa da profundidade de semeadura.

Among studies focused on increasing soybean grain yield, the ones related to sowing process are the most significant. Considering that soybean has an epigeal emergence, it becomes difficult to hint at the length covered by hypocotyl up to soil surface, or the actual planting depth. This study aimed to find an indicator that allows the identification of an ideal soybean planting depth. For this purpose, two complementary assays has been carried out in a greenhouse. The first aimed to identify structures that could be indicators of seed planting depth, on a medium-textured soil from Campos Gerais region, in the state of Paraná, Brazil. Spring NK 8350 cultivar seeds were sown at five theoretical depths (1, 2, 3, 4 and 5 cm). As seedlings emerged, the “differentiation zone” and the “root curve” depths were measured. The second assay was the validation of the suggested indicators in assay 1 from two soils, one medium-textured and one clay-textured. For this assay, it was used BRS 232. Both the methodologies showed high correlation with the theoretical planting depth. Although their correlation coefficient values were close, the differentiation zone appeared to be the most efficient reference with less planting depth overestimation.

No Brasil, os melhores índices em produtividade leiteira encontram-se no Paraná. Tais índices são alcançados devido à seleção genética dos animais e ao manejo alimentar, onde a silagem de planta inteira de milho tem sido largamente utilizada. Objetivando qualidade de silagem, avaliaram-se a influência do teor de matéria seca da cultura do milho como forragem e das regulagens da colhedora sobre o tamanho de fragmento de silagem de planta inteira de milho. Num fatorial 5 x 3, com quatro repetições, analisou-se o tamanho de fragmento da silagem de dois híbridos de milho (SPEED e 2B688). O primeiro fator foram as épocas de colheita (105; 108; 112, 118 e 123 dias após a semeadura (DAS)), as quais determinam os teores de matéria seca (MS) da forragem. O segundo fator consistiu nas regulagens da máquina (2; 6,5 e 11 mm de comprimento teórico de fragmento (CTF)). Para o híbrido 2B688, os teores de MS não mostraram efeito sobre o tamanho médio de fragmento. Porém, para o híbrido SPEED, verificou-se redução no tamanho de fragmento real com a maturação das plantas. Concluiu-se que os teores de MS, bem como as regulagens da máquina podem interferir nos tamanhos de fragmentos reais, de acordo com o genótipo. As alterações das regulagens da colhedora resultaram em tamanhos diferentes de fragmento, porém não correspondentes àqueles indicados pelo fabricante.

In Brazil, the best results in milk production are found in the state of Paraná. Such results are reached through genetic selection of the animals and management of their diets, in which whole plant corn silage is widely used. Aiming the silage quality, it was evaluated the influence of dry matter content of the corn culture as forage and the harvester adjustments on the fragment size of whole plant corn silage. The fragment size of two corn hybrids silage (SPEED and 2B688) was evaluated using a 5x3 factorial, with 4 repetitions. The first factor was the harvest time of the plants (105, 108, 112, 118, and 123 days after sowing (DAS)), which determines the forage dry matter (DM) content. The second factor was the harvester adjustments (2, 6.5 and 11mm of theoretical fragment length (TFL)). The DM content did not affect the average fragment size of 2B688. For SPEED, however, the real fragment size decreased as the maturation of plants increased. The conclusion is that the DM content and harvester adjustments can affect the real fragment sizes, according to different plant genotypes. The alterations of the harvester adjustments resulted in different fragment sizes, however, it were different from those indicated by the manufacturer.