Improving Water-Deficit Stress Tolerance in Rice (Oryza sativa L.) by Paclobutrazol Exogenous Application

Abstract

This study was carried during 2023 successive summer growing season on rice (Oryza sativa L.) variety (Giza 183). The investigation aimed to study the effects of paclobutrazol (PBZ) at 90 and 120 mg/L on rice under water deficit stress conditions on growth, relative water content, chlorophyll (chl.) pigments, antioxidant enzymes activity, anatomical parameters, as well as yield and yield component. The results showed that, the highest values of plant growth parameters, chl. contents, anatomical differences of stem and leaf as well as yield and yield component were achieved by PBZ at 90 mg/L. The results indicated that, application of PBZ at 90 mg/L mitigated the adverse effects of water deficit stress. Therefore, this study recommends spraying paclobutrazol at 90 mg/L one month after rice vr. GIZA 183 transplanting.