Irrigation and Nitrogen Schedule for Enhancing Nutrient Uptake, Grain Nutritional Quality and Protein Content of Wheat (Triticum aestivum L.) under Semi-arid Conditions

Abstract

Background: Efficient irrigation and nitrogen management are essential for improving nutrient use efficiency and grain nutritional quality of wheat (Triticum aestivum L.) under semi-arid conditions. Synchronizing irrigation with crop water demand and nitrogen application with critical growth stages can enhance nutrient uptake, protein synthesis and fertilizer use efficiency. The present study was conducted to evaluate the influence of different irrigation regimes and nitrogen scheduling practices on nutrient content, nutrient uptake and protein content of wheat. Methods: A field experiment was conducted during the Rabi season of 2024-25 at the Research Farm of Vivekananda Global University, Jaipur, Rajasthan, India. The experiment was laid out in a split-plot design with three replications, comprising three irrigation regimes [I1 (three irrigations), I2 (four irrigations) and I3 (five irrigations)] and three nitrogen scheduling treatments [N1 (50% basal + 50% at crown root initiation), N2 (50% basal + 25% at crown root initiation + 25% at jointing) and N3 (33.33% each at basal, crown root initiation and jointing)]. Nitrogen, phosphorus and potassium content and uptake in grain and straw and grain protein content were determined using standard analytical methods and the data were analyzed using analysis of variance. Result: Irrigation regimes and nitrogen scheduling significantly influenced nutrient content, uptake and grain protein content, whereas their interaction remained non-significant. The five-irrigation (I3) recorded the highest nitrogen (1.693%), phosphorus (0.369%) and potassium (0.485%) contents in grain, together with maximum nitrogen (75.63 kg ha-1), phosphorus (16.53 kg ha-1) and potassium (21.72 kg ha-1) uptake by grain and the highest and protein content (10.58%). Among the N levels tested nitrogen applied in three equal splits at basal, crown root initiation and jointing stages (N3) significantly enhanced nutrient concentration and grain protein content, recording the highest grain nitrogen (1.694%), phosphorus (0.370%), potassium (0.484%) and protein content (10.59%). Under the conditions of the present study, five irrigations (I3) recorded the highest N, P and K contents and uptake in grain and straw, while three equal split applications of nitrogen (N3) resulted in the highest nutrient contents, nutrient uptake and grain protein content indicate that integrated management of irrigation and split nitrogen application effectively improves nutrient use efficiency and grain nutritional quality of wheat under semi-arid conditions.