Volume 6, Issue 4 (2-2016)                   2016, 6(4): 63-73 | Back to browse issues page


XML Persian Abstract Print


Dept. of Hort. Sci., College of Agric., Univ. of Tabriz, Tabriz, Iran.
Abstract:   (5267 Views)

Nitrate fertilizers are common source of nitrogen (N) in nutrient solutions. Substitution of urea with nitrate could reduce this dependence. Also, nickel (Ni) is essential for activation of urease in plants fed with urea. For this aim, a factorial experiment was conducted in a completely randomized design with four replicates. Urea in five levels (0, 25, 50, 75 and 100 mg/L) and Ni in two levels (0 and 2 mg/L) were used for lettuce (Lactuca sativa cv. Siyahoo) in hydroponics. The results showed that the highest fresh and dry weight of leaves and stem were obtained in 50 mg/L urea treatment. Leaf area was reduced in treatments having more than 25 mg/L urea concentration. The highest chlorophyll index and maximal quantum yield of PS II photochemistry efficiency (Fv/Fm) were obtained in 100 and 75 mg/L urea, respectively. Total nitrogen concentration of leaves was increased significantly with increasing urea concentration; plants treated with 100 mg/L urea had the highest total nitrogen concentration. Nickel application reduced yield and physiological traits of lettuce; while it had no significant effect on total nitrogen concentration.

Full-Text [PDF 14 kb]   (2446 Downloads)    
Type of Study: Research |
Received: 2016/02/1 | Accepted: 2016/02/1 | Published: 2016/02/1

Add your comments about this article : Your username or Email:
CAPTCHA

Send email to the article author


Rights and permissions
Creative Commons License This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.