Combined Effect of Seed Priming and Organic Amendments on the Agronomic Output of Dry Direct-Seeded Winter Rice in Floodplain Soil of Bangladesh

Abstract

Rice production in the floodplain ecosystems of Bangladesh is increasingly constrained by water scarcity and declining soil fertility, necessitating sustainable and efficient management practices. This study evaluated the effects of seed priming and organic amendments on the growth, yield, water use efficiency, and soil health of dry direct-seeded winter rice (BRRI dhan88). A two-year field experiment (2023 to 2024) was conducted using 3 priming techniques: hydro-priming, halo-priming (CaCl₂), and osmo-priming (PEG 6000 w/v) in combination with organic amendments, particularly vermicompost, alongside recommended fertilizer doses. The experiment was laid out in a randomized complete block design (RCBD) with 3 replications. The total number of plots was 48. Growth traits, yield components, irrigation use, and post-harvest soil properties were measured, and multivariate analyses were conducted to assess relationships among traits. Seed priming significantly improved plant growth and yield compared to unprimed seeds. Hydro-priming produced the highest grain yield (5.73 tons ha-1), exceeding the control (4.08 tons ha-1). Organic amendments, especially vermicompost, further enhanced performance, with recommended fertilizer doses (RDF)+vermicompost yielding 5.60 tons ha-1. Their combined application improved grain yield, reaching up to 6.67 tons ha-1. Organic amendments also reduced irrigation water use by up to 27%, indicating improved water use efficiency. Soil properties improved, with higher organic matter, nutrient content, and balanced pH. Overall, integrating seed priming with organic amendments, particularly vermicompost, offers a practical and sustainable approach to enhance rice productivity, conserve water, and improve soil fertility under water-limited conditions.