Cause and Effect Estimates on Corn Yield as a Function of Tractor Planting Speed

The objective of this work was to explain the cause and effect estimates on corn yield as a function of planting speed. The study was conducted from January 21 to June 15, 2019, at Fazenda Invernadinha, rural area of ​​the municipality of Mineiros, GO, Brazil. The experimental design consisted of randomized blocks, corresponding to five tractor planting velocities (4, 6, 8, 10 and 12 km h-1), in 4 replicates, where each plot consisted of 8 300 m long lines spaced at each 0.9 m, for a population of 60.000 plants ha-1. Sowing was carried out in no-till system after soybean harvest. A John Deere tractor and planter assembly were used, models 7715 (182 hp horsepower) and 2115 CCS Vacumeter (8 rows of 0.9 m respectively) with 30-hole 30 mm seed discs. Data were submitted to the assumptions of the statistical model, verifying the normality and homogeneity of the residual variances, as well as the additivity of the model. The analyzes were performed in the Rbio R interface, besides the Genes Software. It was concluded that the plant population is the variable that most influences the cause and effect estimates on corn yield. For high corn yields it is recommended that the tractor planting speed be adjusted to 6 km h-1.