Univrsity of Tehran Press Iranian Journal of Field Crop Science 2008-4811 52 3 2021 09 23 Effect of tillage, water stress and nitrogen fertilizer on forage quality of maize in Karaj Effect of tillage, water stress and nitrogen fertilizer on forage quality of maize in Karaj 25 40 83813 10.22059/ijfcs.2020.295521.654681 FA Esmaeil Afshon Department of Agronomy and Plant Breeding, University of Tehran, Karaj, Iran. 0009-0001-6645-6209 Hossein Moghadam Department of Agronomy and Plant Breeding, University of Tehran, Karaj, Iran. 0000-0001-8216-281X Mohammad Reza Jahansooz Department of Agronomy and Plant Breeding, University of Tehran, Karaj, Iran. 0000-0001-8536-5911 Saeed Soufizadeh Environmental Research Institute of Shahid Beheshti University, Tehran, Iran. Mostafa Oveisi Department of Agronomy and Plant Breeding, University of Tehran, Karaj, Iran. 0000-0003-0742-5485 Journal Article 2020 01 07 To study the effect of nitrogen fertilizer and irrigation regimes on yield and some qualitative traits of forage maize cultivated under traditional and conservational tillage systems, an experiment was conducted in 2018 in split-split plot on randomized complete block design with three replications in University of Tehran. The effects of tillage as main factor in two levels (traditional and no-till), water stress as the sub-factor in three levels (30%, 60% and 90% of moisture requirement) and nitrogen fertilizer as a sub sub-factor at three levels (0%, 50% and 100% of the recommended rate) were studied on qualitative traits (DMD, WSC, CP, ADF, NDF, CF and Ash) and dry matter of maize plant. The results showed that the highest dry matter of maize (18.3 t ha^-1) was obtained from no-water stress treatment under traditional tillage which was and the lowest (7.2 t ha^-1) was observed in severe water stress under no-till condition. 100% nitrogen fertilizer treatment with no-water stress under traditional tillage produced the highest percentage of crude protein (12.22%)and non-nitrogen fertilizer and moderate water stress treatment under no-till resulted in the lowest crude protein (6.11%) . The highest (25.43%) and lowest (13.27%) percentage of acid detergent fiber in corn forage was obtained from 100% nitrogen fertilizer with severe water stress under conservation tillage and 100% nitrogen fertilizer with moderate water stress under no-till conditions, respectively. Agronomically, it seems that it is not possible to achieve the aims of no-till in short-term. In other words, conservation tillage will be effective after the transition stage. Also, increasing nitrogen content under water stress did not have a positive effect on forage quality. To study the effect of nitrogen fertilizer and irrigation regimes on yield and some qualitative traits of forage maize cultivated under traditional and conservational tillage systems, an experiment was conducted in 2018 in split-split plot on randomized complete block design with three replications in University of Tehran. The effects of tillage as main factor in two levels (traditional and no-till), water stress as the sub-factor in three levels (30%, 60% and 90% of moisture requirement) and nitrogen fertilizer as a sub sub-factor at three levels (0%, 50% and 100% of the recommended rate) were studied on qualitative traits (DMD, WSC, CP, ADF, NDF, CF and Ash) and dry matter of maize plant. The results showed that the highest dry matter of maize (18.3 t ha^-1) was obtained from no-water stress treatment under traditional tillage which was and the lowest (7.2 t ha^-1) was observed in severe water stress under no-till condition. 100% nitrogen fertilizer treatment with no-water stress under traditional tillage produced the highest percentage of crude protein (12.22%)and non-nitrogen fertilizer and moderate water stress treatment under no-till resulted in the lowest crude protein (6.11%) . The highest (25.43%) and lowest (13.27%) percentage of acid detergent fiber in corn forage was obtained from 100% nitrogen fertilizer with severe water stress under conservation tillage and 100% nitrogen fertilizer with moderate water stress under no-till conditions, respectively. Agronomically, it seems that it is not possible to achieve the aims of no-till in short-term. In other words, conservation tillage will be effective after the transition stage. Also, increasing nitrogen content under water stress did not have a positive effect on forage quality. https://ijfcs.ut.ac.ir/article_83813_b5d2f969609f3a1dc89c7c8ec282bc3f.pdf