Document Type : Research Paper

Authors

• M.A Mousavi Shalmani
• N Sagheb
• M.S Hobbi
• S Teimoori
• A Khorasani
• N Piervali

Abstract

In order to determine a suitable level of nitrogen fertilizer for simultaneous increasing the nitrogen fertilizer use efficiency and the yield production under the trickle fertigation system  in comparison with the furrow irrigation, an experimental design was conducted in a randomized complete block (RCB) with five treatments and four replications in plots of 35 square meters area. The treatments of N₀ , N₁ , N₂ and N₃ received 0 , 100 , 150 and 200 mgN/lit, respectively  under the trickle fertigation , and for the treatment of Ns the amount of fertilizer were equal to N₂ but under the furrow irrigation system. Fertilization and irrigation were performed by means of two fertigator pumps  ( one for urea and the other for ammonium phosphate and potassium sulfate ) . In order to determine the nitrogen fertilizer use efficiency, six plants in the middle of each plot received ¹⁵N labeled urea (isotopic form of ¹⁴N) through plastic containers. Irrigation schedule and soil moisture monitoring were performed by means of a neutron gauge . The results showed that in spite of increasing the nitrogen levels in the fertigation system, the nitrogen fertilizer use efficiency decreases. In this respect , the treatment of N₁ could absorb % 54 of nitrogen fertilizer which indicated that the highest fertilizer use efficiency under the current design condition and the final nitrogen fertilizer use efficiency for N₂ and N₃  treatments are %39 and %31, respectively. In addition, the traditional treatment (Ns), with %83 losses of nitrogen had the lowest rate of fertilizer use efficiency.     

Highlights

1. ن. ثاقب و همکاران,  “استفاده از روش ایزوتوپی ازت – 15 برای تعیین کارآیی اوره در کود- آبیاری گوجه فرنگی،” مجموعه مقالات کوتاه هفتمین کنگره علوم خاک ایران، شهرکرد، صفحات420-419 (1380). 

      

2. م. ا. موسوی شلمانی و همکاران، “برآورد و مقایسه کارایی مصرف اوره طبق روشهای تفاضلی و ایزوتوپی در گیاه گوجه فرنگی تحت سیستم کود- آبیاری قطره‌ای،”  نشریه علمی سازمان انرژی اتمی ایران، شماره 24، صفحات 55-47 (1380).

    

    

    

    

    

    

    

    

    

    

    

    

    

    

    

3. IAEA, “Use of nuclear techniques in studies of soil – plant relationships,” Training Course Series, No. 2, 26-34 (1990).

    

4. I. Papadopoulos, “Fertilizer in irrigated agriculture and potential pollution impact (step by step),” Technical Report, Agricultural Research Institute, Nicosia, Cyprus (1995).  

Keywords

• 15N
• trickle fertigation
• furrow irrigation
• nitrogen fertilizer use efficiency
• nitrogen levels
• tomato