The Effect of Slow Release Nitrogen from N Enriched Cow Manure Pellet on Nitrogen Efficiency and some Morphological Characteristics and Grain Yield of Corn (Single Cross 704)

To evaluate the effect of nitrogen slowly released from pellet, composed of manure and urea fertilizer on the Nitrogen efficiency and morphological Characteristics and grain yield of corn hybrid (S.C704), a field experiment was carried out in Aboureihan research farm of Tehran University in 2009. The factorial design of the study comprised a randomized complete block with three replications. The application rates of N at four levels (46, 92, 138 and 184 kg N. ha-1) and two levels by methods of N distribution (pellet and mixed with soil) were applied. In this research, a Screw Extruder setup was designed and manufactured. Statistical analysis indicated that NUE, as well as agronomic efficiency (AE) was reduced while physiological efficiency (PE) increased with increasing N rates. Also, most plant length and stem diagonal and cob diagonal pellet belonged to the treatment. But, the number of leaves per plant did not affect the distribution method of fertilizer.The results showed significant differences among various rates of nitrogen and methods of N distribution considering grain yield and grain protein. The higher rates of N increased grain protein, grain yield and yield components (except for number of rows per ear). Maximum grain yield (11.1 t. ha-1) was obtained with 184 kg N. Ha-1 treatment.