Determination of Effects the Different Holes Position in the Vacuum Discs of Pneumatic Precision Vegetable Planters on Emergence and Uniform Plant Distribution in Black Carrot Production.

The objective of this study was to determine the seed releasing characteristics of seed metering discs used in the precision seeding of black carrot seeds. High precision vegetable seeder was tested in the field conditions using black carrot seeds in Kuzukuyu village of Ereğli-Konya in 2018. Three different seed metering discs that have holes in three different circle positions were used in the experiments. These applications referred to seeding techniques, ST1, ST2 and ST3. The seed metering discs with three trajectories, each diameter was 210, 185, and 155 mm respectively. Each trajectory on vacuum plate using in ST1 had equal number of holes (96 holes), while P1 and P2 hole positions had same number of holes in ST2 ve ST3, however, 25% and 50% decrease in the number of holes in the P3 (bottom hole position), respectively. The downforce on the press wheel was kept constant throughout all trials. In these three different seeding techniques, the planting performance of the machine under field conditions was evaluated and the coefficient of variation values expressing the seed distribution uniformity, mean of the emergence rates were determined. According to the results, the mean of emergence rates and coefficient variation values were determined as %59.86 ve %76.84, %68.91 ve %75.31, %66.26 ve %72.48for ST1, ST2 ve ST3, respectively. Given hole positions (planting rows), emergence rates and CV values were obtained %59.71 ve %81.94 for P1, %62.69 ve %74.49 for P2 and %72.60 ve %68.20 for P3. [ABSTRACT FROM AUTHOR]