Effect of TNAU Rice Bloom Foliar Application on Fertile Panicle Production and Grain Yield of Rice (Oryza sativa L.)

Abstract

High-temperature and low-light stresses during the reproductive stage are important constraints to panicle development, grain filling and grain yield in rice (Oryza sativa L.), particularly during the Samba season in Tamil Nadu. Field demonstrations were conducted during the Samba season of 2024–2025 in ten farmers' fields across Poondi, Kadambathur, Ellapuram and Tiruvallur blocks of Tiruvallur district to evaluate TNAU Rice Bloom as a foliar crop booster under farmers' field conditions. The rice variety CO 55 was used in all demonstrations. TNAU Rice Bloom was applied at 2 kg acre⁻¹ at the heading stage, followed by a second foliar spray at the same dose ten days after the first application, using 200 L of water acre⁻¹. Treated plots were compared with untreated control plots in terms of grain yield, fertile panicle production and economic returns. Grain yield in the control plots ranged from 5,145 to 5,440 kg ha⁻¹, whereas TNAU Rice Bloom-treated plots recorded 5,985 to 6,158 kg ha⁻¹. Demonstration-wise yield increase ranged from 10.51% to 16.42%. The economic analysis showed higher gross and net returns in the TNAU Rice Bloom treatment than in the control. The mean number of fertile panicles increased from 13.86 panicles hill⁻¹ in the control to 15.89 panicles hill⁻¹ with TNAU Rice Bloom, representing an increase of 14.67%. These findings indicate that foliar application of TNAU Rice Bloom at heading and ten days later may improve fertile panicle    production, grain yield and economic returns under the stress-prone rice-growing conditions evaluated in this study.