ABSTRACT. Pearson's correlation and spatial variability are tools that can be used to help one understand the process of losses in the mechanical harvesting of cotton. Therefore, the objective of this study was to model the spatial distribution and map the losses of mechanical cotton harvest using geostatistics and to correlate the losses with agronomic variables using Pearson’s correlation. The experiment was conducted in Itiquira and Lucas do Rio Verde, Mato Grosso State, Brazil. At each sampling point, the evaluated variables were agronomic plant variables and cotton losses in the soil and the plant (divided into lower, medium and upper thirds) and the sum total of losses. The highest losses in cotton harvest occurred in the lower third and on the soil, both of which exhibit a spatial dependence model, according to geostatistics, demonstrating that they do not occur in a randomized process and are related to the specific plant. There was a relationship between the plant populations with losses in the cotton crop. The plant population can influence the spatial dependence of losses.

RESUMO Com a expansão de áreas de cultivo de cana-de-açúcar, a adubação mecanizada mostra-se fundamental por proporcionar maior desempenho operacional, otimização do fornecimento de nutrientes, aumento da produtividade. Porém, esta adubação pode apresentar algumas deficiências na distribuição, tais como, fluidez, segregação, granulometria, entre outros. Assim, está sendo desenvolvido um novo conceito de adubação, capaz de realizar aplicação individualizada de nitrogênio, fósforo e potássio, distribuindo-os com diferentes dosagens; maior eficiência de aplicação; utilização da agricultura de precisão e taxa variável. Objetivou-se com este trabalho avaliar a qualidade da adubação mecanizada individualizada de NPK em cana-soca por meio do Controle Estatístico de Qualidade - CEQ. O experimento foi desenvolvido no município de Matão, São Paulo. A área experimental pertence à Fazenda Cascavel. O delineamento experimental foi baseado nas premissas básicas do CEQ ao longo do espaço, monitorando a adubação mecanizada individualizada de NPK em 30 pontos amostrais. As parcelas desse tratamento foram compostas por seis linhas de cana-de-açúcar, espaçamento entrelinhas de 1,5 m, área útil 1.571 m2 e a cada 30 m coletou-se por 5 segundos o fertilizante nos pontos amostrais. O mecanismo dosador helicoidal foi uma das causas especiais que afetou a qualidade operacional, pois não foi eficiente na distribuição. Concluiu-se que a qualidade da adubação individualizada de fertilizante aplicou a dosagem acima da recomendada para todos os fertilizantes, devido à regulagem e o mecanismo dosador helicoidal. O nitrogênio (ureia protegida) apresentou maior variabilidade de distribuição enquanto o fósforo (MAP) apresentou a melhor qualidade operacional devido a menor quantidade recomendada.

ABSTRACT With the expansion of areas of sugarcane cultivation, mechanised fertilisation is essential for providing improved operational performance, optimising the supply of nutrients and increasing productivity. However, this type of fertilisation may present deficiencies in the area of distribution, such as fluidity, separation, and particle size, among others. A new concept in fertilisation is therefore being developed, capable of carrying out the individual application of nitrogen, phosphorus and potassium, distributing these in various doses, with greater efficiency of application, employing precision farming and variable rates. The aim of this study was to evaluate the quality of the individual mechanised fertilisation of NPK in ratoon cane by means of Statistical Quality Control - SQC. The experiment was carried out in the city of Matão, in the State of São Paulo, with the experimental area making up part of the Cascavel Farm. The experimental design was based on the basic premise of spatial SQC, monitoring the individual mechanised fertilisation of NPK at 30 sampling points. For this treatment, the lots were composed of six rows of sugarcane, spaced 1.5 m apart, with an effective area of 1,571 m2. There was a sampling point every 30 m, where fertiliser was collected for 5 seconds. The helical metering system especially affected operational quality, as this was inefficient in its distribution. It was concluded that, due to adjustment of the helical metering system, individual application resulted in doses above those recommended for all fertilisers. Nitrogen (protected urea) showed the greatest variability in distribution, whereas phosphorus (MAP) displayed the highest operating quality due to the lower recommended volume.

RESUMO Escolhas no manejo cultural, como a do cultivar e a do sistema de colheita, podem influenciar os índices dos parâmetros de qualidade da fibra do algodão. Objetivou-se, com este trabalho, analisar as características das fibras de dois cultivares de algodão submetidos a diferentes sistemas mecanizados de colheita (picker e stripper). O experimento foi conduzido na safra de 2012, com espaçamento de 0,45 m entre linhas, no município de Juscimeira, MT. Utilizou-se delineamento em blocos casualizados, em esquema de parcelas subdivididas, com dois fatores, sendo eles, A, nas parcelas (dois cultivares) e B, nas subparcelas (três sistemas de colheita - manual, picker e stripper), com cinco repetições. A qualidade da fibra foi determinada em amostras coletadas manualmente da planta e, após a colheita mecanizada, retiradas de dentro do cesto armazenador de cada colhedora. As análises das características das fibras foram realizadas em Laboratório de Classificação de Fibras, com o aparelho HVI (High Volume Instrument). As fibras do algodão colhido com o sistema manual, em seguida, sistema picker apresentam melhores características e melhor qualidade que as das fibras colhidas com stripper.

ABSTRACT Choices in crop management such as cultivar and harvesting system can influence fiber quality parameters. This study aimed to evaluate fiber characteristics of two cultivars in narrow row cotton submitted to different mechanized harvesting systems (picker and stripper). The experiment was conducted in season 2012, with 0.45 m, at Juscimeira - MT. It was used randomized block design in split plot with two factors, factor A in the plots (two cultivars) and factor B in the subplots (three harvesting systems - manual, picker and stripper), with five replications. The quality of the fiber was determined in manually collected samples of plants and after harvest, withdrawn inside the basket of each harvester. The analysis of the characteristics of fiber, were analyzed in Laboratory of Classification of Fiber in apparatus by HVI (High Volume Instrument). Fibers picked with manual, followed by picker system have characteristics and better quality compared to fibers harvested with stripper.