%0 Journal Article %T The Effect of Nitrogen fertilizer and Poultry Manure on Yield and Nitrate Residuals in Autumn Onion Crop in Jiroft Region %J Iranian Journal of Soil and Water Research %I University of Tehran %Z 2008-479X %A Sarhadi, Javad %A heidari, saber %A Sharif, Mehri %D 2021 %\ 11/22/2021 %V 52 %N 9 %P 2415-2425 %! The Effect of Nitrogen fertilizer and Poultry Manure on Yield and Nitrate Residuals in Autumn Onion Crop in Jiroft Region %K Urea %K Onion %K Nitrate %K Onion bulbs and leaves %R 10.22059/ijswr.2021.326288.669008 %X This study was conducted to evaluate the application of poultry manure and urea fertilizer in onion in the randomized complete block design with three replications during 2018 and 2019. The treatments were:1-Control (276 kg/haN), 2-Recommended optimal nitrogen limit for the region crop (184 kg/haN)+Optimal consumption of other nutrients, 3- nitrogen consumption 25% more than the optimal limit+Optimal consumption of other nutrients, 4-Consumption of nitrogen 25% less than the optimal limit+five t/ha of poultry manure+optimal consumption of other nutrients and 5-Consumption of nitrogen 25% less than the optimal limit+tent/ha of poultry manure+Optimal consumption of other nutrients. The results showed that the effects of treatments on yield, the concentration of other elements, and nitrate residuals in onion bulbs and leaves were significant at the level of 1% probability. The control had the lowest yield (43.3t/ha) and the highest nitrate residuals (184.3 and 571.2mg/kg, respectively) and the lowest concentrations of potassium, iron, zinc, and manganese in bulbs and leaves. Also, treatment five showed the highest yield (25.1% increase compared to the control), and no significant difference in yield was observed between treatments four and five. The lowest nitrate residuals in bulbs were in treatment four, which was 69.9%, 21.7, 43.3, and 3.4% less than treatments one, two, three, and five, respectively. The application of treatment four, while reducing the consumption of urea fertilizer by 50% and as a result of reducing nitrate in bulbs to less than the critical level and increasing the yield by 18%, resulting in about 11% more revenue than the control. %U https://ijswr.ut.ac.ir/article_85223_9752fdad8555127694abd9ae015d11b1.pdf