Evaluation of effects of different tillage systems, planting row spacing and plant densities on grain yield and yield components of corn

In order to investigate the effects of tillage systems and plant densities in two plant pattern, on kernel yield and its component on corn (Zea mays L.cv.sc704), an experimental design, randomized complete block in a strip factorial was used, treatments arrangement with four replications in north of Iran in 2010-2011. Main plot was subjected to tillage systems in three levels: 1. Rotary system (RS). 2. Disk system (DS) - 3. Plow and Disck system (PDS). Other factors were plant density in three levels (60000, 70000 and 80000 plant/ha) and plant pattern were conventional row (linear) and new two rows (zigzag). The results indicated that all traits, were not affected by tillage systems, while the grain yield and 1000 seeds weight, which were affected by plant density showed significant difference. With the increase of density from 60000 to 80000 plants/ha, grain yield and 1000 seeds weight increased, an amount of from 9.09 to 11.14 t/ha and 332.35 to319.52 gr respectively. Grain yield and 1000 seeds weight were not affected by plant pattern.