Disturbance of Ultisol soil based on interactions between furrow openers and coulters for the no-tillage system

The present study evaluated the effect of different associations between coulters and fertilizer furrow openers on soil disturbance, furrow depth and width, according to forward speed. The study was conducted on a farm in Santa Maria (Brazil/RS), in soil classified as sandy loam Ultisol. The experiment consisted of 24 combinations of treatments with three replications in a 2×3×4 factorial experiment. The combinations were formed by the interaction of the factors including: two types of furrow openers (hoe and double-disc), three types of coulters (no-coulter, smooth and offset fluted) and four levels of forward speed (1.11, 1.67, 2.22 and 2.78 m/s). Soil elevation and soil disturbance area profiles were obtained with the use of a micro profilometer, and disturbance values were calculated with the aid of computer software program Auto Cad. The disturbance area was not affected by speed; it was greater when using the hoe opener, and in association with the offset fluted coulter. Speed was inversely proportional to the depth of the furrows made by the hoe opener. Furthermore, the hoe caused the greatest furrow width (0.26 m) in comparison with the double-disc (0.24 m). The use of different coulters associated with furrow openers increased this variable (0.23 m for the no-coulter condition, 0.25 m with smooth and 0.26 m with offset fluted). The use of coulters combined with furrow openers reduces soil swelling, in approximately 8% for the smooth and 20% for the offset fluted

Demanda energética e mobilização do solo com o uso de escarificadores em sistemas de semeadura direta

A redução das janelas de semeadura e a intensificação da produção no sistema de semeadura direta impulsionaram o aumento na frequência de utilização de máquinas, provocando compactação pelo tráfego. A compactação, além de prejudicar o desenvolvimento das raízes das plantas, aumenta a demanda de potência dos implementos justificando a utilização de escarificadores para a descompactação do solo. Avaliou-se o desempenho de dois escarificadores (Haste + ponteira), sendo um comercial e um experimental, com vistas a entender a operação de escarificação quando adaptada ao sistema de semeadura direta, utilizando como parâmetros variáveis energéticas e de solo. O elemento descompactador experimental teve um desempenho superior ao comercial nas principais variáveis estudadas, tais como consumo de combustível, potência e força de tração. Quando à frente dos elementos descompactadores o disco de corte não alterou a força de tração mas reduziu o consumo de combustível e a potência. O aumento da velocidade proporcionou incremento da força de tração, potência e consumo de combustível

Effect of different conductor tubes on the longitudinal distribution of corn seeds

ABSTRACT The correct longitudinal distribution of seeds by the seeder machine is one of the features that most contributes to obtain an adequate plant stand and good crop yield. The objective of this study was to evaluate the longitudinal distribution of corn seeds by seed conductor tube types, combined with a horizontal perforated disc and a pneumatic meter, altering the seeding density rate. The experiment was conducted in a laboratory using a seed meter test bench. Treatments were a combination of two seed meters, six conductor tubes and four peripheral speeds for the meter disc, corresponding to densities of 60, 70, 80 and 90 thousand corn seeds per hectare and were organized in a three-factor scheme with four repetitions. By increasing the seeding rate into the same ground speed, there was a reduction in the percentage of acceptable spacing, this effect being more pronounced when conductor tubes with a small diameter and straight profile were used

Modelos estatísticos para seleção de dosadores helicoidais com diferentes dispositivos de descarga de fertilizante

O presente trabalho teve por objetivo desenvolver uma ferramenta capaz de expressar matematicamente a taxa de aplicação de fertilizante em função do tipo de dosador, inclinação longitudinal, inclinação transversal e velocidade de acionamento do dosador. Foram utilizados três dosadores helicoidais com dispositivos de descarga por gravidade, transbordo transversal e transbordo lateral e adotado o delineamento composto central rotacional, com três variáveis independentes. A partir dos modelos ajustados constatou-se que os dispositivos de descarga apresentam diferentes implicações em relação aos efeitos de inclinações longitudinais e transversais de operação. O dosador com descarga por gravidade demonstrou maior sensibilidade quanto aos efeitos das inclinações de operação e o dosador com descarga por transbordo lateral demonstrou menor sensibilidade. A análise de regressão demonstrou que todos os modelos foram significativos, sendo encontrados baixos erros relativos e absolutos dos dados previstos pelos modelos

Effect of different conductor tubes on the longitudinal distribution of corn seeds

<div><p>ABSTRACT The correct longitudinal distribution of seeds by the seeder machine is one of the features that most contributes to obtain an adequate plant stand and good crop yield. The objective of this study was to evaluate the longitudinal distribution of corn seeds by seed conductor tube types, combined with a horizontal perforated disc and a pneumatic meter, altering the seeding density rate. The experiment was conducted in a laboratory using a seed meter test bench. Treatments were a combination of two seed meters, six conductor tubes and four peripheral speeds for the meter disc, corresponding to densities of 60, 70, 80 and 90 thousand corn seeds per hectare and were organized in a three-factor scheme with four repetitions. By increasing the seeding rate into the same ground speed, there was a reduction in the percentage of acceptable spacing, this effect being more pronounced when conductor tubes with a small diameter and straight profile were used.</p></div