Planting represents one of the most important soil management operations in the corn  production technologhnology,because in case eni  drawbacks in planting take place , they cannot be compensated afterwards. The aim of work is to point out that the rate of corn grain yield (beside quality seeding material, time of planting, soil, climatic conditions) most of the times highly depends on the right choice of technical solution of the seeder  and the possibility for conforming to the given planting norm at changing the working speed of the sowing aggregate. During the experiment, we monitored the work of the pneumatic seeder IMT-634-454 (air-suction pneumatic seeder) at a working speed ranging from 4 km/h to 10 km/h.The aim of research is to determine the optimal speed of the sowing aggregate in order to comply  for qu for quality planting. The research program encompassed the evaluation of the planting depth, the achieved interspaces in the rows, the precision of the planting, the dynamics of the plants’ motion, productivity, as well as the final result effect of the examined factors to the corn grain yield at various working speeds of the sowing aggregate. It is noted that the speed of the sowing aggregate significantly affects the quality of planting, where the largest deviations, comparing to the given norms of a quality planting, happen at working speed of 10 km/h, so that beside the fact that the most favourable effects are  achieved at a higher speed the limiting factor for working of the examined seeder at higher speed achieved quality of planting.The first year of  the research was very unfavourable in terms of climate comparing  to the second year that was favourable, which reflected on the rate of the corn grain yield. The highest grain yield.  was obtained in the more favourable year, at a speed of 4 km/h, because, at the same speed, the bigger set of plants was achieved, which is in the state of interaction with the favourable climatic factors and gave a result with the highest grain yields, whereas in the unfavourable year, at the same speed of 4 km/h, the attained grain yield was the lowest due to the interaction of the achieved number of plants per hectare with unfavourable climatic conditions..In exploitation examination of the seeder, the most favourable values are attained at a speed of 10 km/h, but there is a quality planting appearing as a limiting factor, which doesn’t comply to the given criteria at higher speeds.Correct choise is not onli the sowing machine ,his way of work are important for increase  grain yield. Therefore, by this examination, we come to a conclusion that the optimal working speed of the pneumatic seeder IMT-634-454 in planting corn is from 6 km/h to 8 km/h.On base  of results we found that diference  working speed of pneumatic sseeder are very important for precision sowing

pnematic seeder,corn, working sped

Presentation: oral