Effect of Irrigation Regimes and Nitrogen Scheduling on Growth Attributes of Wheat (Triticum aestivum L.) under Semi-arid Conditions

Abstract

A field experiment was conducted during the Rabi season of 2024-25 at the Research Farm of Vivekananda Global University, Jaipur, Rajasthan, India, to evaluate the effects of irrigation regimes and nitrogen scheduling on the growth of wheat (Triticum aestivum L.). The experiment comprised nine treatment combinations involving three irrigation regimes, viz., three irrigations (I₁), four irrigations (I₂), and five irrigations (I₃), and three nitrogen scheduling treatments, viz., N₁ (50% basal + 50% at crown root initiation (CRI)), N₂ (50% basal + 25% at CRI + 25% at jointing stage) and N₃ (33.33% at each of the basal, CRI, and jointing stages). The treatments were evaluated in a split-plot design with three replications. Irrigation regimes and nitrogen scheduling had no significant effect on plant stand at 20 DAS and at harvest. However, both factors significantly influenced plant height and dry matter accumulation from 60 DAS onwards. Among the irrigation regimes, five irrigations (I₃) produced the maximum plant height (68.14, 83.06, and 87.58 cm at 60 DAS, 90 DAS, and harvest, respectively) and dry matter accumulation (145.81, 189.65 and 250.71 g m⁻¹ row length at 60 DAS, 90 DAS and harvest, respectively). Similarly, nitrogen applied in three equal splits (N₃) recorded the highest plant height (67.32, 82.00 and 87.61 cm) and dry matter accumulation (146.00, 189.00 and 250.63 g m⁻¹ row length) at the corresponding growth stages. The findings indicate that five irrigations and nitrogen applied in three equal splits at the basal, CRI, and jointing stages, considered as separate management effects, provided favourable conditions for sustained vegetative growth by improving plant height and biomass accumulation. These management practices may therefore be considered for enhancing wheat growth under semi-arid agro-ecological conditions.