Unlocking the Potential: Impact of Plant Growth Regulators on Hybrid Rice Growth, Grain Yield and Harvest Index

Abstract

Aim: This research focused on rice, especially in Asia, and examined how plant growth regulators, including hormones and synthetic compounds, affect crucial plant processes. The findings strongly support the use of foliar Indole-3-Acetic Acid (IAA) application to enhance hybrid rice growth, grain yield, and harvest index, promising advancements in agriculture. Study Design: Randomised Block Design with 11 treatments. Place and Duration of Study: The study, conducted at the Student Instructional Farm of C. S. Azad University of Agriculture & Technology in Kanpur, aimed to investigate the impact of foliar application of plant growth regulators on rice growth and yield during 2021 and 2022. Methodology: The experiment employed a rigorous randomized block design, testing various treatments involving the foliar application of IAA (25 & 50 ppm), IBA (25 & 50 ppm), NAA (25 & 50 ppm), Ascorbic Acid (50 & 100 ppm), and Kinetin (5 & 10 ppm). The profound effects of these different regulator concentrations were observed at key developmental stages, including tillering, anthesis, dough, and maturity. Results: Significant improvements in growth parameters, such as leaf and stem dry weights per plant, along with total leaf area per plant, were evident with the application of IAA at 50 ppm. Moreover, a notable increase in grain yield per plant and harvest index was observed at maturity, primarily with the foliar spray of IAA at 50 ppm, followed closely by IAA at 25 ppm. This consistent trend was also observed in yield-related attributes. Conclusion: The use of Indole-3-acetic acid (IAA) significantly impacted plant growth and yield, including leaf and stem dry weights, leaf area, grain yield, and harvest index, showing promise for enhancing hybrid rice production.