Impact of hydrogel under different fertiliser and irrigation levels on growth, yield and its contributing traits of barley (Hordeum vulgare L.)

The application of polymeric hydrogel improved barley seed germination under low-quality irrigation water, indicating enhanced moisture availability during early growth. In dual-purpose barley systems, initial fodder harvesting did not adversely affect subsequent grain yield when crop management remained comparable to grain-only production. A field experiment was conducted during the rabi seasons of 2023–24 and 2024–25 at the research farm, Mandawa, Jhunjhunu district, Rajasthan, to study the effect of irrigation levels and hydrogel application under different fertiliser doses on the growth, yield and yield attributes of barley (cv. RD-2035). The experiment was carried out in a split-plot design (SPD) in 3 replications. The main plot consisted of 3 irrigation levels, while the subplots included 6 hydrogel–nutrient treatments (100, 70 and 50 % nitrogen, phosphorus and potassium (NPK) with and without hydrogel at 2.5 kg ha-1). Hydrogel was applied in seed rows at sowing to enhance soil moisture retention. Growth and yield parameters such as plant height, tiller number, dry matter accumulation, flag leaf area and yield attributes were recorded at different stages of crop growth. The irrigation treatment (I3) produced the tallest plants, maximum tillers, dry matter accumulation and highest grain, straw and biological yields, followed by irrigations (I2). The irrigation (I1) treatment recorded the lowest values for all parameters. Results indicated that irrigation levels significantly affected growth and yield attributes. Similarly, the combined application of hydrogel at 2.5 kg ha-1 with 100 % NPK (H₂) resulted in significantly higher plant growth, spike length, number of grains per spike, test weight and overall productivity compared to other nutrient combinations. The improvement in grain yield due to hydrogel application was attributed to enhanced water and nutrient availability throughout the growth period. The study concludes that irrigation (I3) with hydrogel application at 2.5 kg ha-1 and 100 % NPK (H₂) fertilisation effectively improves growth, yield attributes and water use efficiency of barley under semi-arid conditions of Rajasthan.