Effect of nitrogen levels, plant growth regulators and cutting management on growth, yield and yield attributes of dual-purpose barley (Hordeum vulgare L.)
Abstract
A field experiment was conducted during the rabi seasons of 2023–24 and 2024–25 at Mandawa, Jhunjhunu district, Rajasthan, India, to evaluate the combined effects of nitrogen (N) levels, plant growth regulators (PGRs) and cutting management on growth, yield and yield attributes of dual-purpose barley (Hordeum vulgare L.) variety RD 2715. The experiment was laid out in a factorial randomised block design (FRBD) with 18 treatment combinations comprising three cutting schedules (40, 50 and 60 days after sowing (DAS)), 3 N levels (100, 125 and 150 % of recommended dose of nitrogen (RDN)) and two PGRs (chlormequat chloride (CCC) at 1.25 L ha-1 and ethephon (cerone) at 0.5 L ha-1), replicated thrice. Results revealed that cutting management significantly (p ≤ 0.05) influenced growth and yield parameters. Cutting at 60 DAS produced the highest green fodder yield, whereas cutting at 40 DAS recorded significantly higher grain yield, straw yield and yield-attributing traits, including effective tillers, spike length, grains per spike and test weight. Nitrogen application significantly improved growth parameters such as crop growth rate (CGR), relative growth rate (RGR), leaf area duration (LAD), chlorophyll content and flag leaf area. Application of 125 % RDN significantly enhanced most growth and yield attributes and remained statistically at par with 150 % RDN, indicating diminishing marginal returns beyond the optimum N level. Among PGRs, CCC at 1.25 L ha-1 proved superior to ethephon by significantly improving vegetative growth, tiller density, chlorophyll content and yield attributes, resulting in higher grain, straw and biological yields. Overall, integration of early fodder cutting (40 DAS), optimum N application (125 % RDN) and CCC application emerged as an effective agronomic strategy for maximising grain yield while maintaining adequate fodder production in dual-purpose barley under semi-arid conditions.