Enhancing Morpho-Physiological and Yield Potential of Rice using Nutrients and Plant Growth Regulators

Rice (Oryza sativa L.) is one of the major cereals and the staple food crops which is cultivated all over the world. In order to meet the growing demand of population, it is important to increase the productivity of crop. The productivity of crop is influenced by nutrients and growth hormones. With this background, a field experiment was conducted during the month of January-May 2023 at wetland farms, Tamil Nadu Agricultural University, Coimbatore, Tamil Nadu, India to evaluate the effect of different foliar nutrients and growth regulators on growth, physiology, biochemical and yield attributes in rice. The experimental layout was Factorial Randomized Block Design (FRBD) with two varieties (CO55 and ADT 57). The treatments consisted of foliar spray of T1- Control (water spray), T2- Nutrio-hormonal consortia 1, T3- Nutrio-hormonal consortia 2, T4- Rice booster 1 and T5- Rice booster 2 given at the booting stage and 15 days after the first spray. Among the treatments, T5- Rice booster 2 significantly improved leaf area (1813.99 cm2, 2059.78 cm2), leaf area index (4.53, 5.15), crop growth rate (32.07 g/m2/day, 37.89 g/m2/day), chlorophyll index (37.60, 41.73), photosynthetic rate (27.15 µmol CO2 m-2 s-1, 30.04 µmol CO2 m-2 s-1), Transpiration rate (11.83 mmol H2O m-1 s-1, 14.20 mmol H2O m-1 s-1 ), soluble protein content (16.23 mg/g, 17.30 mg/g), nitrate reductase activity (98.15 µg of NO2/g/h, 112.47 µg of NO2/g/h) in ADT- 57 variety at both sprays, respectively. Foliar application of rice booster 2 (T5) resulted in higher number of productive tillers (23), number of spikelets per panicle (165.5), spikelet fertility (95.48%), 1000 grain weight (17.35g), grain yield/ plant (31.40g), grain yield/hectare (6694.32 Kg/ha), harvest index (45.44%) in ADT 57 and resulted in 15% yield increment over the control. Thus the present study concluded that the foliar application of rice booster 2 (T5) significantly improved the growth, physiology, biochemical and yield attributes in rice variety ADT 57.