Effect of nitrogen fertitiztion and growth stage on physiological growth character and fresh forage yield of corn (Zea mays L.)

Abstract

A Field experiment was carried out in autmun season of 2012 at AL- Hemidat / Thaljah village 20km West of Mosul city and Bashiqa / Tobzawh village 25 km East of Mosul City to study the effect of four fertilization treatments no fertilizer (1), fertilization with 450kg N/ha at sowing (2), Fertilization with 225 kgN/ha at sowing and 225 kgN.ha-1 20 day Aftera emergency and fertiliztion with 150 kgN/ha at sowing and 150 kgN.ha-1 20 dyas after emergency and 150 kmN/ha 30 day after emergencye and clipping at three growth stages (25 , 50 and 75 %Tassling) on growth and forage yield of corn variety Bohoth 106 The experiment was Split plot in Randomized Compelt Blok Desing (RCBD) with three replications. Most of studied Characters at both Locaions were significantly effected by nitrogen fertili- zation treatment with expet the Relative Growth Rate (RGR) and Net Assi- milation Rat (NAR) at Tobzawh and Crop Growth Rate (CGR) at both locaions. The higest fresh forage weight was achevied at Tobzawh (59.8 ton/ha) and Thaljah (59.17 ton.ha-1) with, Fertilization treatment (4). Also ,most studied characters were affected by growth stages and the highest forage fresh weight was achevied at Tobzawh (57.21 tons/ha) and (50.5 tons.ha-1) at 75% Tassing growth stage. The interaction between treatmet and growth stages signifticantly affected studied characters at both locations except for nitrogen Use Effiency at Thaliah village location and Crop Growth Rate at both locaions.