Effect of deficit irrigation on drip-irrigated wheat grown in semi-arid conditions of Upper Egypt

ABSTRACT

Shortage of water in arid and semi-arid regions increases the need of applying efficient drip irrigation system. A two-year field study in the semi-arid region of Upper Egypt was carried in randomized complete block design with four replicates. Wheat plants were irrigated by 100 or 75% of water requirements (I₁₀₀ = 5,370 and I₇₅ = 4,027 m³ ha⁻¹). Irrigation of wheat by I₁₀₀ increased growth and uptake of nitrogen, phosphorus, and potassium compared to low irrigation level. I₁₀₀ caused 14 and 5% increase in straw and biological yield, respectively, compared to I₇₅. Grain yield and water use efficiency (WUE) were higher by 20 and 59% in the case of I₇₅ compared to I₁₀₀. The use of deficit irrigation in drip-irrigated wheat under arid conditions is an effective tool to maximize efficiency of water use; moreover, 4,027 m³ ha⁻¹ is the optimum irrigation rate for maximum WUE and grain yield.

KEYWORDS:

• drip irrigation
• N, P, and K uptake
• water use efficiency
• wheat