Evaluation of Rhizosphere Environment, Growth, and Yield Components of Rice Affected by No-Puddling and Mid-Season Drainage

Abstract

Traditional paddy cultivation relying on intensive puddling and continuous flooding faces severe sustainability challenges from labor shortages, soil degradation, and high greenhouse gas emissions. However, the interactive effects of combining no-puddling (NP) and mid-season drainage (MD) on the rhizosphere environment and yield remain unclear. This two-year field study (2024–2025) evaluated the combined impact of tillage (puddling, P vs. NP) and water regimes (continuous flooding, CF vs. MD) on rice performance and soil properties. Combined MD-NP accelerated soil redox potential (Eh) recovery (up to −271 mV) during drainage, mitigating soil reduction toxicity. MD-NP effectively restricted excessive internode elongation, suppressed unproductive tillering, and maximized root dry weight at heading (8.38 g plant−1 in 2025; up to 29.5% higher than CF). In 2025, MD-NP achieved the highest brown rice yield (4.89 t ha−1; 20.4% higher than CF-P), primarily driven by increased grains per panicle (82.5) and ripened grain percentage (76.5%). Three-way ANOVA confirmed significant main effects of tillage (p = 0.036) and water management (p = 0.003) on yield. Additionally, MD-NP better preserved soil organic matter and total carbon. Overall, MD-NP provides a climate-resilient, low-carbon, and sustainable paddy management strategy that conserves water and labor while securing yield.