Effect of plant growth regulators on phenological study and growth analysis of mung bean (Vigna radiata L.) under central plain zone of Uttar Pradesh

This study investigates the effects of various plant growth regulators (PGRs) on the phenological and growth parameters of mung bean (Vigna radiata L.) under the central plain zone of Uttar Pradesh. Conducted during the Kharif seasons of 2023 and 2024 at Chandra Shekhar Azad University of Agriculture and Technology, the experiment utilized a randomized block design comprising 33 plots across three replications. Treatments included control and PGR applications of Indole-3-acetic acid (IAA), Gibberellic acid (GA3), Maleic hydrazide (MH), 2, 3, 5-Triiodobenzoic acid (TIBA), and Kinetin. Key phenological observations included days to flowering initiation, days to 50% flowering, and days to maturity. Growth analyses measured crop growth rate (CGR), relative growth rate (RGR), and relative water content (RWC). Results indicated significant variations in phenological traits across treatments. In 2023, days to flowering initiation ranged from 28.07 (GA3@40 ppm) to 32.40 (Kinetin@15 ppm), while in 2024, it was from 26.47 (GA3@60 ppm) to 30.80 (Kinetin@15 ppm). Days to 50% flowering similarly ranged from 30.13 to 34.27 days in 2023 and from 28.60 to 32.80 days in 2024. Maturity periods ranged from 52.00 to 56.00 days in 2023 and from 50.73 to 54.93 days in 2024. Growth analysis revealed that CGR ranged from 11.12 to 15.38 g/m²/day (2023) and 10.37 to 16.14 g/m²/day (2024). The maximum RGR recorded was 0.27 mg/g/day for Kinetin treatments in both years. RWC was highest at 70.54% (Kinetin@10 ppm) in 2023 and 70.64% (Kinetin@15 ppm) in 2024. Overall, Gibberellic acid (GA3) and Kinetin demonstrated the most promising effects on phenological and growth parameters respectively, suggesting its potential to enhance mung bean productivity and support sustainable agricultural practices.f