عنوان مقاله [English]
نویسندگان [English]چکیده [English]
In order to modeling the output required in corn, an experiment was conducted with a factorial arrangement based on a randomized complete block design with three replications at Research Fields of University of Tehran in 2007. Two factors including four levels of N fertilizer (0, 180, 270, and 360 kg ha-1of Urea fertilizer 46 %) and five doses of Nicosulfuron herbicide (0, 20, 40, 60, and 80 g. ai ha-1) were used. According to the equation fitted on data, to achieve high yield, 250 kg ha-1 N fertilizer and 38 g ai ha-1 Nicosulfuron herbicide dose (i.e reaching to the 50 % of the yield) are needed. Also, the data fitted by line level showed that the highest corn grain yield (almost 11 t ha-1) and corn biomass (8 t ha-1) were observed with 270 kg ha-1 N fertilizer and 80, 60 g. ai ha-1 Nicosulfuron herbicide treatments. Besides, the lowest corn grain yield and biomass yield (3 t ha-1) were obtained in the treatment used no N fertilizer and herbicide dose. The results showed that application of N fertilizer up to 360 kg ha-1 resulted in higher herbicide dose used for appropriate weed control. Consequently, N fertilizer must be applied in farm based on weed density and species.