ABSTRACT Active optical sensors have been widely used for the spatial and temporal monitoring of peanut culture because they are accurate, non-destructive methods for rapidly obtaining data. The objective of this study was to determine the optimal stage of crop growth for collecting sensor readings based on correlations between quality indicators. In addition, we compared vegetation indices (Normalized Difference Vegetation Index [NDVI], Normalized Difference Red-Edge Index, [NDRE], and Inverse Ratio Vegetation Index, [IRVI]) by monitoring temporal variability in the peanut crop in order to determine which of them obtained the best reading quality throughout the process. The experiment was performed on the 2016/17 crop in the agricultural area of the municipality of Dumont in the state of São Paulo, Brazil. The experimental design was based on the basic assumptions of statistical quality control and contained 63 sample points in a 30 × 30 m grid. The parameters were evaluated at 30, 45, 60, 75, and 119 days after sowing (DAS) using proximal sensing with GreenSeeker and OptRX sensors. We found that 45 and 60 DAS were the optimal times for monitoring peanut crop variability. For spatiotemporal monitoring of the culture with control charts, NDRE showed the best readings throughout the process when compared to NDVI and IRVI.

ABSTRACT: The intensive mechanization during the harvest operation and success of this operation depends on several factors, one of which is the length and format of the plots. The aim of this study was to evaluate the operating performance of a soybean harvester in different geometric plots shape, using as quality indicators performance parameters by means of statistical control tools of process. The experiment was conducted in March 2014 in the city of Uberaba - MG. Operational capacity was evaluated in the mechanical harvesting of soybeans in three plots: irregular, rectangular and trapezoidal. Performance evaluations of soybean harvester were made from the following parameters: displacement speed, engine rotation, cylinder rotation and concave opening. The grain water contents affect the quality indicators of the soybean harvester performance in all plots shapes. The harvester performance is considered able to maintain between the specification limits and close to the target, to speed quality indicators the irregular and the trapezoidal plots and for cylinder rotation the trapezoidal plot.

ABSTRACT: A new concept of fertilizer machine is under development and shows as differential individually fertilizer application, that is sources of N, P and K are applied separately for the purpose of improving the distribution efficiency of the quantities applied. The aim was to compare the quality of the individualized mechanized distribution of N, P and K in combined operations with and without herbicide application, as well as to evaluate the fertilizer application on each side of the fertilizer machine. The experiment was carried out on Cascavel farm, in the municipality of MatãoSP. The experimental design was established according to the criteria of quality control, and variables monitoring carried out in the place during fertilization operation, having the fertilizer distribution operation; simultaneous operation of fertilizer distribution and herbicide application treatments; and two simple operations, fertilizer distribution followed by herbicide application. We concluded that the better operational quality was in two distinct operations. The right side of the fertilizer had the best result because it applied the amount close to the regulated dosage. The distribution of potassium chloride expressed in the control charts greater operational quality compared to other fertilizers.