EFFECT OF DIFFERENT AMOUNTS OF NITROGEN FERTILIZER ON GRAIN YIELD OF FORAGE CORN CULTIVARS IN ISFAHAN

To evaluate the effect of nitrogen fertilizer amounts on grain yield of forage corn in 2012, a pilot was implemented in Islamic Azad University Agricultural Research Station, Isfahan, as a split plot in a randomized complete block design. Main plots consisted of four levels: control (no fertilization ) , 50 , 100 and 150 kg per ha nitrogen from urea source and subplots , including several varieties of corn ( single cross 704 , single cross 640 and single cross 540 ), respectively. Results indicate that the effect of nitrogen fertilizer and cultivar effects on the number of rows per ear, number of seed per row, number of grains per maize, seed weight and seed yield were significant. With more than 704 varieties of seed number per row and number of seeds per ear, more grain yield was produced. The 540 cultivar was not significantly different. Treated with 150 kg N ha- highest number of seed per rows and number of seeds produced. Treatment of 100 kg per hectare produced the highest seed weight and seed yield and seed weight could generate the maximum highest yield significantly different results, and treatment was 150 kg N ha. Thus, the results indicate that treatment of 100 kg per ha nitrogen to achieve maximum yield was good