EffEcts of strip Width and tractor forWard spEEd on soWing Uniformity of maizE and sUnfloWEr

AltikAt, S., 2013. Effects of strip width and tractor forward speed on sowing uniformity of maize and sunflower. Bulg. J. Agric. Sci., 19: 375-382 A two year field experiment was conducted to investigate the effects of strip width and tractor forward speed on sowing uniformity of maize and sunflower. Being equipped to achieve purpose of this study, a row crop rotary hoe with C-type blades was used to obtain different strip widths. During the experiment, the field area was tilled in 22.5, 30 and 37.5 cm wide strips, respectively; these widths were obtained by changing the positions of flanges and blade connections of the rotary hoe. The rotary hoe was operated at a constant rotor rotation speed of 370 min-1, in a tillage depth of 10 cm and at 3 different tractor forward speeds (1.8, 3.6 and 5.4 km h-1 ) in order to get various soil fragmentation values. Because of increasing the forward speed during the tillage, coefficient variations of sowing depth uniformity, intra and inter-row seed distribution uniformity and seed distribution area for both maize and sunflower seeds decreased. The precision of the distribution of the seeds along the length of the row for the forward speeds was well below 29%; and therefore, it was acceptable for both maize and sunflower seeds. However, the strip width did not have a significant effect on the sowing performance parameters. Tractor forward speed became effective on soil fragmentation, and accordingly the distribution of smaller soil particles decreased with the increase in the speed. This study demonstrated that the most acceptable tractor forward speed for the strip tillage method in terms of the sowing uniformity parameters was 1.8 km h-1 for all of the experiment years.