Optimization of gibberellic acid dose for mungbean (Vigna radiata) under hot arid climate

The present study was carried out during rainy (kharif) seasons of 2018, 2019 and 2020 at the Agricultural Research Station, Mandor, Agriculture University, Jodhpur, Rajasthan to optimize the application rate of gibberellic acid during critical growth stages to enhance mungbean [Vigna radiata (L.) R. Wilczek] yield and economic returns. The experiment was conducted in a randomized block design (RBD) comprised of 8 treatments, viz. T1, Absolute control; T2, Water spray at flowering and pod initiation; T3, GA3 at 30 ppm spray at flowering initiation; T4, GA3 at 30 ppm spray at pod initiation; T5, GA3 at 45 ppm spray at flowering initiation; T6, GA3 at 45 ppm spray at pod initiation; T7, GA3 at 30 ppm spray at both flowering and pod initiation; and T8, GA3 at 45 ppm spray at both flowering and pod initiation, replicated thrice. Results indicated that the foliar application of GA3 at 45 ppm during flowering and pod initiation (T8) led to a significant increase of 36.26% in the number of pods/plant compared to the control. Additionally, both the T8 treatment and T7 showed statistically comparable effects on plant height, seeds/pod, root nodules/plant and biological yield. The seed yield increased significantly by 36% with the foliar application of GA3 at 45 ppm during flowering and pod initiation compared to the control. Moreover, the sustainability yield index (SYI) and production efficiency (PE) were notably higher with the application of GA3 at 45 ppm during flowering and pod initiation (T8), demonstrating a 1.4-fold increase in each parameter relative to the control. This treatment also yielded higher net returns of ₹63,853/ha and a benefit-cost ratio (B:C) ratio of 3.9, surpassing the other treatments. These findings emphasize the critical role of GA3 in promoting sustainable agricultural practices, highlighting its potential to enhance crop productivity and economic viability in the challenging agricultural environment of arid regions.