Effect of Foliar Application of Selected Plant Growth Regulators on Growth and Yield of Soybean Glycine max (L.) Merrill

Background: Soybean (Glycine max), a prized oilseed crop known for its nutritional richness, is the focus of a study aiming to boost production with minimal environmental impact. The research explores the application of plant growth regulators (PGRs), specifically Gibberellic Acid (GA3), Kinetin and Salicylic Acid, in field experiments during the kharif seasons of 2022 and 2023 in Beed, India. Methods: The study applied Gibberellic Acid (GA3), Kinetin and Salicylic Acid at different concentrations in field experiments. A comprehensive analysis of growth and yield attributes, including plant height, primary branches, Leaf Area Index (LAI), root nodules and Crop Growth Rate (CGR), was conducted to assess the influence of PGR treatments on soybean growth. Yield attributes such as pod count, pod weight, seed count per pod and 100-seed weight were scrutinized to understand their effects on soybean productivity. Result: The study highlighted significant effects of PGR treatments on soybean growth and yield. Notably, Kinetin at 500 ppm promoted the tallest plants, while GA3 at 200 ppm resulted in the shortest. Kinetin at 100 ppm increased primary branches and Salicylic Acid at 50 ppm exhibited the highest LAI and abundant root nodules. Kinetin at 500 ppm and Salicylic Acid at 50 ppm showed higher CGR, indicating efficient crop growth. For yield, Kinetin at 500 ppm excelled in pod count and weight. GA3 at 100 ppm was identified as the most effective PGR for enhancing various growth parameters and soybean seed yield, suggesting the potential of PGRs in sustainable cultivation, reducing reliance on chemical inputs.