ABSTRACT Grain losses pose a threat to agricultural sustainability, particularly in developing countries. Mechanized harvesting is a key process in which losses occur; thus, its investigation is essential. Therefore, a systematic and meta-analytical review was conducted to encompass studies on quantitative soybean losses during harvesting in South America from the last two decades. The initial search yielded 1,094 scientific articles; however, only 25 studies met the inclusion criteria. This study provides an overview of technical aspects monitored on farms, guidelines to ensure efficient harvesting and literature gaps for further innovations. Because studies on soybean losses were predominantly based on continuous observational data and lacked methodological quality according to a quality scoring, only four studies were included in the meta-analysis. The meta-analysis results showed a significant relation between losses and the combine age, indicating that combines with over 10 years of use result in higher losses than newer ones (p ≤ 0.05). Conversely, operating at speeds exceeding 5 km h-1 did not lead to significant increases in soybean losses (p > 0.05). Many decisions can be taken at the farm-level to reduce losses, such as proper training of workers and adequation of combine harvesters according to each crop condition. The insights described here are timely for paving the way towards innovation in harvesting systems and minimizing grain losses by understanding the critical points within the context improving yields during soybean harvesting.

RESUMO As perdas de grãos ameaçam a sustentabilidade na agricultura, especialmente em países em desenvolvimento. A colheita mecanizada é um importante estágio em que as perdas ocorrem, sendo crucial investigá-la. Portanto, uma revisão sistemática e meta-analítica foi conduzida para analisar estudos das últimas duas décadas no tema de perdas quantitativas de soja durante a colheita mecanizada na América do Sul. A pesquisa inicial resultou em 1094 artigos científicos, entretanto, apenas 25 estudos foram selecionados devido ao critério de inclusão estabelecido. Essa revisão descreve uma visão ampla dos aspectos técnicos monitorados no campo, instruções para garantir uma colheita eficiente e lacunas da literatura para futuras inovações. Os estudos foram predominantemente baseados em dados contínuos e observacionais, além de possuírem falhas metodológicas de acordo com uma pontuação qualitativa. Assim, apenas quatro estudos foram incluídos na meta-análise. Os resultados mostraram uma relação significativa entre perdas relacionadas à idade da máquina, indicando que colhedoras com mais de 10 anos de uso produziram perdas maiores que as novas (p ≤ 0.05). Por outro lado, operar em velocidades maiores que 5 km h-1 não levou a um aumento significativo das perdas de grãos (p > 0.05). No campo, muitas decisões podem ser tomadas para reduzir as perdas, e.g., treinar operadores e configurar a colhedora de acordo com as condições da lavoura. As discussões apresentadas nessa revisão são importantes para guiar as inovações em sistemas de colheita e diminuir as perdas de grãos ao entender os pontos críticos em um conceito de maior lucratividade durante o processo.

ABSTRACT Statistical process control has been widely used in agricultural operations for monitoring and improving process quality. This study aims to evaluate the Shewhart and exponentially weighted moving average (EWMA) control charts to monitor the performance of an agricultural tractor–planter set. The design is completely randomized based on the assumptions of statistical process control and comprises two treatments: day and night shift treatments. The data to assess the performance of the tractor–planter set are collected during the day and night shifts and used to evaluate the operating speed, motor rotation, engine oil pressure and water temperature, and hourly fuel consumption. The dataset comprised 40 samples compiled from the frontal monitor column inside a tractor cab. It is concluded that both Shewhart and MMEP/EWMA control charts can be used to evaluate engine performance based on the quality indicator parameters investigated, regardless of the normality assumption of the datasets.

ABSTRACT Sugarcane mechanized harvesting can lead to serious risks to the longevity of plantations when improperly operated, and may cause damages and disturbances in the remaining ratoons in the field. In this sense, this study aimed to evaluate the damage and disturbance to the sugarcane ratoons by the base cutting quality of two-blade models through statistical process control. The experiment was carried out during the 2015/16 growing season in an agricultural area of the Moreno Mill, located in Cravinhos, São Paulo, Brazil. The sugarcane harvester models A8800 (Machine 1) and BE1035 (Machine 2). The sugarcane variety cultivated in both treatments was SP80-1816. Thirty points were sampled per harvester, with 10-minute intervals between them. Equations were used to calculate the indices, which were then evaluated through descriptive analysis and statistical process control. Machine 2 presented process instability for the index of damages, with lower data variability. On the other hand, Machine 1 presented instability during the process due to the quality indicator and index of disturbance, but with a lower operation variability.

ABSTRACT Although peanut harvesting results in significant losses, it has rarely been investigated. Thus, this study aimed to analyze the interference of different pod moisture contents on peanut harvesting and their influence on the process quality based on losses and impurities. An experiment was performed in a peanut seed producing area, in Luzitânia, district of Jaboticabal - SP, using average moisture contents of 15% and 20% in the pods; 16 and 14 data points were collected for the 20% and 15% treatments, respectively. The experimental design used statistical process control (SPC) to analyze the collected variables. The results indicated higher losses in the platform than in the machine. In addition, the harvest quality was not affected by the pod moisture content. However, the correct adjustment of machines can restrict total losses to approximately 1% of the yield. Pods with moisture contents of 15% and 20% can be used for peanut harvesting. However, although a pod moisture content of 15% reduced the amount of mineral and vegetal impurities inside the bulk tank, the number of open pods increased, whereas a pod moisture content of 20% provided a greater number of whole pods.

ABSTRACT The mechanized sugarcane harvesting process is considered one of the major economic bottlenecks, with low operational efficiency and, mainly, high losses of stalks left in the field. In order to minimize these problems and assist in the improvement of processes, this study aimed to evaluate the losses in the mechanized sugarcane harvesting using statistical process control. The experimental design was completely randomized, based on the methodology of statistical process control with samples collected on five work fronts during the daytime and nighttime operation. The experiment was carried out in an agricultural area of a sugarcane mill in the municipality of Ribeirão Preto, SP, Brazil, on five sugarcane harvest fronts. Losses were measured using a 3.0 × 3.33-m frame, being divided into stump, loose piece + fixed piece, whole sugarcane, fragment, and total losses for each harvest front. The data were grouped into 50 weeks over the sugarcane-growing season, and statistical analyses were performed using the Minitab 16® software. Losses of loose piece + fixed piece were higher than the losses of stump, whole sugarcane, and fragment. The total losses showed higher and lower losses for the fronts F5 and F4, respectively, compared to the others.

ABSTRACT Sugarcane harvester cutting blade wear increases ratoon damages and losses, impairing sugarcane regrowth. This study aimed to evaluate the quality of basal cut using ratoon damage and loss indexes and correlating them with effects on sugarcane regrowth. Harvest parameters such as plant height and position, damage and loss indexes, and stem length were evaluated every 30 min, following statistical process control (SPC) assumptions. Blade wear was examined during three harvesting shifts (0-8 h, 8-16 h, and 16-24 h). Sugarcane regrowth was assessed by counting number of tillers and measuring plant height and stem diameter. The second harvesting shift showed better quality in terms of damage and loss indexes, and plant height and stem diameter. Harvesting was considered out of control for parameters such as cutting height, number of tillers, plant height, and stem diameter. On the other side, it was regarded as under control for damage and loss indexes, and plant high and position. The first shift presented peripheral or no damages and weak to medium loss levels, whereas the second and third ones showed extreme damages and medium to strong losses.

ABSTRACT The way the soil is managed can influence its structuring and, consequently, crop yield. Thus, this study aimed to evaluate the effect caused by the management systems plowing followed by two intermediate harrowing operations, intermediate harrowing, chiseling, chiseling followed by intermediate harrowing, cross chiseling followed by intermediate harrowing, and non-tillage on soil and agronomic attributes of the soybean crop. A randomized block design with four replications was used. The percentage of soil cover, soil resistance to penetration, number of plants per meter, longitudinal distribution of seedlings, and soybean yield were evaluated. The data were submitted to analysis of variance by the Tukey test at 5% probability, and use of geostatistics for soil resistance to penetration. The system without soil tillage provides the best straw preservation but affects the longitudinal distribution of soybean seedlings. The use of intermediate harrowing for managing crop residues or soil tillage leads to the greatest compaction problems. Chiseling is efficient in maintaining compaction values below critical values up to a depth of 0.20 m when working at 0.35 m. Soil yield is not affected by soil management systems when the pluviometric regime is adequate to crop requirements.

ABSTRACT The mechanized harvesting of sugarcane has increased exponentially in recent years because of the gradual prohibition of burning on the cane fields in mechanizable and non-mechanizable areas. This study aimed to evaluate the wear of the basal cutting knives in two different mechanized sugarcane harvesters, through statistical process control. The experiment was conducted in Cravinhos, São Paulo, in an agricultural area, on July 25, 26, and 27, 2016. Two harvesters with different basal cutting mechanisms were evaluated: harvester A—Model BE1035e (conventional type knife), and harvester B—Model A8800 (racket type knife). The experimental design was completely randomized with two treatments. The wear was quantified by measuring the thickness increase and width losses of each knife, and it was evaluated for each harvester every 2 hours, during 3 days of operation. Data were evaluated using descriptive statistics and statistical process control. The harvester B model (racket knife) presented lower variability in the cutting width and stability in the cutting width of the knives. The harvester A model (conventional knife) presented greater wear in the width, but less variability in the thickness of the cutting wire.

ABSTRACT Fertilization systems that allow higher sowing speeds have been used in areas of grain production, as well as the use of intercropping to improve soil physical quality and provide better soil cover. This study aimed to evaluate soil attributes and the initial corn development and intercropping (corn + velvet bean, corn + pigeonpea, and corn + bonavist bean) as a function of fertilization systems (pre-sowing and sowing). The experiment was conducted in an Oxisol in a randomized block design in the 2 × 3 factorial scheme, with four replications. The number of days for emergence, plant stand, intercropping dry matter, soil straw cover, soil straw permanence index, penetration resistance, soil moisture, soil density, degree of compaction, and total soil porosity were measured. The percentage of soil straw cover was affected by fertilization system, mainly by pre-sowing fertilization. Soil physical attributes were not affected by fertilization and intercropping systems, except total porosity, in the 0–0.10 m layer, which has a combined effect of factors. The initial corn development was not affected by fertilization and intercropping systems. Velvet bean presented the highest number of days for the emergence and lower dry matter.

ABSTRACT Work in the field is characterized as unstructured because it is performed in inconvenient postures, without a fixed workstation, exposing the worker directly to the sun and other inclement weather. This may interfere in the health and the performance of the activity. The objective of this work was to characterize the environment of the agricultural microtractor operator, evaluating the thermal comfort during the activity in the municipality of Quixadá, CE. A model TC14 Super Yanmar Agritech microtractor, coupled to a rotary spindle, was used. For the measurements of the environmental variables, sensors and devices were installed on the operator and in the microtractor. The experimental design adopted the assumptions of statistical quality control. Fifteen collections were done daily at different times for three consecutive days. The data obtained were indices of thermal discomfort and thermography, both of which were analyzed by sequential graphs (run charts), control graph (Xbar-R chart), and scatter plot. At all rates, the work performed proved to be inadequate, exceeding the operator's capabilities and limitations. It was concluded that the activity performed by the microtractor operator is stressful. Measures should be taken to improve working conditions without affecting the operator's health.

RESUMO O sucesso da lavoura de soja depende de diversos fatores, entre eles cita-se a utilização de sementes de elevada qualidade fisiológica a fim de garantir a obtenção da população de plantas desejada na lavoura. Dessa forma, objetivou-se, por meio das ferramentas do Controle Estatístico de Processo (CEP), monitorar possíveis falhas no processo de produção das sementes e buscar relação entre os testes de germinação e tetrazólio. O delineamento experimental foi baseado nas premissas do CEP, utilizando como indicadores de qualidade a porcentagem de germinação, viabilidade das sementes, danos mecânicos, por percevejo e por umidade. Foi possível detectar falhas no processo de produção de sementes de soja por meio das cartas de controle, dos testes de germinação e tetrazólio, sendo principalmente estas causas relacionadas a danos mecânicos e ataque de percevejos.

ABSTRACT The success of soybean cultivation depends on several factors, one which is the use of high-quality seeds, which can guarantee growth of the desired plant population. The objective of this study was to monitor possible failures during the seed production process, and to determine the association between germination and tetrazolium tests through tools of Statistical Process Control (CEP). The experimental design was based on premises of the CEP, using percentage of germination, seed viability, mechanical damage, bed bug, and moisture as indicators of quality. It is possible to detect flaws in the soybean production process through control charts, as well as through germination and tetrazolium tests; results indicated that germination failures are largely caused by mechanical damage and bed bug attacks.

RESUMO A qualidade da colheita mecanizada de soja é essencial para garantir que todo investimento realizado nas demais etapas do processo produtivo da cultura seja convertido em lucro para o produtor. Considerando que a qualidade dessa operação está relacionada com menores perdas e que a plataforma de corte utilizada e a velocidade de colheita podem influenciar nisso, objetivou-se avaliar a qualidade da colheita mecanizada da soja, no Cone Sul de Rondônia, em colhedoras com diferentes plataformas de corte e velocidades de deslocamento por meio do controle estatístico de processo. O experimento foi realizado na safra 2015/16 em uma área agrícola no município de Cabixi, RO, localizada nas coordenadas geográficas 13º 27’ S e 60º 41’ W. O delineamento experimental foi estabelecido de acordo com as premissas do controle estatístico de processo, sendo amostrados 80 pontos distanciados a cada 100 m. Avaliaram-se as perdas na plataforma, nos mecanismos internos e totais e a altura de corte. A melhor qualidade do processo de colheita foi obtida na plataforma de esteira, com pouca influência da velocidade de deslocamento. O nível de perdas na colheita foi acima do limite aceitável, indicando necessidade de melhorias do processo.

ABSTRACT Assuring the quality of mechanical soybean harvesting is crucial to ensure that investment in other stages of crop production is converted into profit for the farmer. Because the quality of this operation is related to decreased losses, which may be affected by the combine header used and by the harvesting speed, the aim of the present study was to assess the quality of mechanical soybean harvesting in the Southern Cone of Rondônia, using harvesters with different combine headers and travel speeds via statistical process control. The experiment was performed during the 2015/16 harvest in an agricultural area of the municipality of Cabixi, RO, located at the geographical coordinates 13° 27’ S and 60° 41’ W. The study was designed based on the premises of the statistical process control, sampling 80 points 100 m apart. Combine header, internal, total, and cutting height losses were assessed. Quality of the harvesting process was assessed using the draper header. Travel speed had little effect on process quality. Crop losses were higher than the acceptable limit, indicating the need to improve the process.

ABSTRACT The use of automatic routing significantly increases the yield and quality of agricultural operations and reduces the overlap rates between the mechanized set passes during the operation. The objective of this study was to analyse the quality of peanut sowing using automatic routing in two paths, curved and rectilinear, based on the error of parallelism and execution error, through statistical process control. The maps used came from an area of peanut seed production, in the city of Luzitânia, São Paulo, Brazil. The sowing was carried out by the execution of a project elaborated in CAD software that, for its elaboration, was taken into consideration the working width of the seeder-fertilizer, as well as the spacing of the crop. The CenterPoint RTX signal was used on both routes. The errors were measured in the Agrocad® program, by means of the orthogonal difference between the lines, and the execution errors were calculated based on the difference between the previously projected lines and the lines executed by the tractor. In general, the sowing operation presented better quality in the rectilinear path, providing smaller parallelism and execution errors. The maximum errors of parallelism were 8.75 and 5.22 cm in the curved and rectilinear path, respectively. The RTX signal ensured good quality of operation in rectilinear path, with low probability of errors occurrence above 3.8 cm.

RESUMO O preço do algodão é determinado pela qualidade da fibra, que pode ser danificada no momento da colheita, além de perdas quantitativas de pluma não colhidas. Neste contexto, o estudo teve como objetivo analisar as perdas no solo e na planta e a qualidade da fibra de algodão em relação a cinco velocidades de colheita (5, 6, 7, 8 e 9 km h-1) no sistema de fusos. O experimento foi realizado em Lucas do Rio Verde, Mato Grosso, Brasil. Um delineamento de blocos completamente casualizados (DBC) foi usado em talhão de 0,9 ha, 20 parcelas, 5 velocidades e 4 repetições. Concluiu-se que as velocidades estudadas não influenciaram significativamente as perdas no solo e na planta e a qualidade da fibra de algodão, recomendando-se usar a velocidade mais alta.

ABSTRACT Cotton price is determined by the quality of the fiber, which can be damaged at the time of harvest, in addition to quantitative losses of non-harvested plume. Therefore, this study aimed to analyse soil and plant losses, and the quality of cotton fiber in relation to five harvest speeds (5, 6, 7, 8, and 9 km h-1) in the spindle system (picker). The experiment was conducted in Lucas do Rio Verde, Mato Grosso, Brazil. A randomized complete block design was used on plots of 0.9 ha, with 20 plot, five speeds, and four blocks. The results showed that the studied speeds did not significantly influence losses on the soil and plant, or the quality of the cotton fiber; therefore, the highest speed may be recommended.

ABSTRACT The performance of the tractor-seeder can be influenced by factors related to the seeder, as loads and crop. The aim of the present study was to evaluate the performance of tractor-seeder at sowing in the corn crop in function of the fertilizer systems (at presowing and at sowing) and those intercropping of crops (corn + bean-Stizolobium deeringianum, corn + bean-Cajanus cajan and corn + bean-Dolichos lab lab). The experiment was carried out at FCAV-UNESP with totally randomized delineation, on factorial scheme (2x3) with four repetitions. The use of fertilization during the pre-sowing resulted in greater displacement speed and effective field capacity in the corn sowing operation, without changing the distribution of corn seeds; however, it demanded more power and volumetric and weight hourly consumption of the tractor fuel.