Supplemental irrigation and fertilization to mitigate the adverse effect of terminal drought stress on transplanted aman rice

Abstract

An experiment was conducted at Crop Physiology and Ecology Research Field, Hajee Mohammad Danesh Science and Technology University (HSTU), Dinajpur during July to December 2021 to assess the impact of terminal drought stress on T. Aman rice and evaluate the efficacy of supplemental irrigation and additional fertilizer application for sustainable production. The study was arranged in split-plot design with three replications. Main plot treatment consisted of three water management options such as I₀- Rain-fed (Control), I₁- One supplemental irrigation (6 cm) at flowering stage, I₂- Two supplemental irrigations (6 cm) at panicle initiation and flowering stage. Sub plot treatment consisted of four nutrient management as, F₁- Recommended doses of inorganic fertilizer (RDF), F₂- 150% of RDF, F₃- 15 t ha^-1 Farmyard manure + RDF and F₄- 10 t ha^-1Biochar + RDF. Rice variety BRRIdhan-94 was used as planting material. Results indicated that T. Aman rice suffered from terminal drought stress affecting growth, physiology and yield attributes. The impact of supplemental irrigation on plant height, tillers hill^-1, grains panicle^-1, thousand grains weight and grain yield of  T. Aman was found significantly positive but there was no significant variation between one and two supplemental irrigations. Additional fertilization, particularly with cattle manure, effectively mitigated the adverse effects of terminal drought stress on T. Aman rice yield. Overall, the study suggests that either one supplemental irrigation or additional fertilization is sufficient to sustain yield under terminal drought stress condition in T. Aman rice cultivation.

Bangladesh J. Agril. Res. 48(3): 335-348, September 2023