Urea Foliar Fertilization Affects Onion Weight and Nutrient Content

ABSTRACT

Foliar application is used to supply fertilizers to developing crops. This method provides flexibility to the producer in their application. This research was undertaken to investigate effects of foliar application of urea on onion (Allium cepa L.), cv. Salamony, in Syria. Four levels of urea, 0, 2,000, 3,500, and 5,000 mg·L⁻¹, were evaluated. Plants were treated with 16.6 mL/plant of urea three times, at 3-day intervals, starting 26 days after planting. Salamony can positively respond to up to 5,000 mg·L⁻¹ of urea without hazard of leaf burn, and bulb fresh and dry weights increased as urea concentration increased. Nitrogen (N), phosphorus (P), potassium (K), and total cation contents of bulbs were increased, but magnesium (Mg), calcium (Ca), and sodium (Na) contents were not affected by treatment. The 5,000 mg·L⁻¹ treatment proved to be the most effective in increasing bulb fresh and dry weights and increasing mineral uptake.

KEYWORDS:

• Allium cepa
• content
• fertilizer
• nutrients
• Syria
• weight

The authors thank the director general of the Atomic Energy Commission of Syria (AECS) and the head of the Molecular Biology and Biotechnology Department for their support of the project.