Impact of Salicylic Acid and Potassium Silicate in Ameliorating the Drought Stress Effect on Sorghum (Sorghum bicolor L. Moench)

Abstract

Aims: The present study highlights the impact of salicylic acid and potassium silicate in reducing the deleterious effect of drought stress on sorghum. Study Design:  Split plot design. Place and Duration of Study: Agricultural College Farm, Bapatla, Andhra Pradesh during rabi, 2023-24. Methodology: The experiment consist of two main treatments i.e., water stress treatments viz., M1 (stress treatment i.e., moisture stress was imposed from vegetative to flowering (25-70 DAS) and M2 (No stress treatment) and eight sub treatments viz., No spray (S1), K-Silicate @50ppm at 35+45 DAS (S2), K-Silicate @100ppm at 35+45 DAS (S3), SA @150ppm at 35+45 DAS (S4), SA @200ppm at 35+45 DAS (S5), K-Silicate @50ppm + SA @200ppm at 35+45 DAS (S6), K-Silicate @100ppm + SA @200ppm at 35+45 DAS (S7) and K-Silicate @150ppm + SA @200ppm at 35+45 DAS (S8) replicated thrice. The plant samples were collected on 30, 50 and 70 DAS. Results: The sorghum plants under water stress showed drastic reductions in chlorophyll content (54.9%), relative water content (34.1%) and increase in membrane injury index (1.9 folds), proline content (1.8 folds) and catalase activity (3.6 folds). The combined spray of potassium silicate @100ppm + SA @200ppm exhibited superior performance by enhancing the chlorophyll content by 59.1%, relative water content by 32.5, proline content by 26.1%, catalase activity by 30.4% and reducing membrane injury index by 28.9%. Conclusion: It can be concluded that the foliar application of @100ppm + SA @200ppm at 35 + 45 DAS helped the sorghum plants from the negative effects of water stress from vegetative to flowering stages.