Application of Phosphorus, Iron, and Silicon Reduces Yield Loss in Rice Exposed to Water Deficit Stress

Abstract

Core Ideas Application of phosphorus, iron, and silicon was able to arrest the yield decline under water deficit stress. There was no significant interaction among phosphorus, iron, and silicon on grain yield. Application of these nutrients increased drought tolerance in plants. ABSTRACTA foremost challenge in rice (Oryza sativa L.) production is to identify suitable nutrient management strategy for reducing yield loss under water deficit stress (WDS) condition. This study investigated the interactive effects of water regime and nutrient management on grain yield and stress metabolites. Accordingly, a 2‐yr field experiment in factorial design with two levels of water management (i) well watered (WW; maintaining 5 ± 2 cm standing water) and (ii) water deficit stressed (WDS) to −60 kPa and two levels of supplementary P, Fe, and Si application was conducted. As compared to WW condition, WDS saved 52 and 46% irrigation water in 2014 and 2015 respectively, however the grain yield decreased by 32–34% under WDS as compared to WW. Application of P, Fe, and Si under WDS condition significantly increased grain yield by 7, 9, and 12%, respectively. Reduced relative water content and increased activity of osmolyte (proline) and antioxidant metabolites (catalase and peroxidase) due to application of P, Fe, and Si contributed to tolerate the WDS, which resulted in higher grain yield. Due to absence of significant interaction between P, Fe, and Si on grain yield, there was no significant advantage of application of more than one of these nutrients together. The results indicate that, application of P, Fe, and Si can increase rice grain yield and can reduce the yield loss under WDS as compared to WW condition in silt loam textured soil in Eastern India.