تاثير تنش خشكي و ميزان نيتروژن خاك بر جذب عناصر غذايي در ذرت رقم 704

Effect of Water Stress and Soil Nitrogen on Nutrients Absorption in Corn Plant KSC 704

In order to determine the effect of water stress and different soil nitrogen on absorption of some macro and micro nutrients in corn plant KSC 704, a field experiment was carried out in a completely randomized block design with factorial layout in three replications in 2004. Treatments consisted of: 150, 300 and 450 kg N/ha as urea sources and water stress consisted of TO (non water stress), T1 (water stress in vegetative stage before pollination and 50% flowering), T2 (water stress in reproductive stage two weeks before tasseling and at a time when 50% of tassel appeared), T3 (water stress in grain filling period expressly after the end of pollination and milk development). The results showed that nitrogen fertilizer affected amount of phosphorus, potassium, manganese and iron absorption (P<0.01). Different levels of irrigation also affected the amount of phosphorus, nitrogen, potassium, zinc, manganese, iron and copper. Increasing nitrogen fertilizer, enhanced nitrogen, phosphorus, potassium and manganese absorption but absorption of iron decreased. Among different water stress treatments, the most and lowest decreasing effect on absorption of nitrogen, phosphorus and potassium respectively, were related to TO and T2. The water stress, increased potassium, zinc and copper absorption but it caused a decrease in manganese absorption. Manganese and iron absorption are negatively related.