Enhancing rice grain yield and quality synergistically through controlled irrigation and increased planting density in nitrogen‐reduced systems

BACKGROUND: Ensuring high yield and improved grain quality is crucial for stabilizing rice production and guaranteeing food security. The present study aimed to investigate whether controlled irrigation and increased planting density within a nitrogen-reduced system can synergistically enhance grain yield and quality to secure food supply. The hybrid indica rice variety Jingliangyou534 was cultivated in the field using four management practices: traditional high-yield cultivation (CK), mono reduced nitrogen rate (MN), reduced nitrogen rate with increased planting density (DN), and DN combined with alternative wetting and moderate soil drying irrigation (CDN). RESULTS: The findings indicated that the nitrogen-reduced systems resulted in a grain yield reduction of 0.64-6.08% but enhanced cooked rice taste and comprehensive by 8.37-27.66% and 4.15-8.71%, respectively, compared to CK. The grain yield of hybrid indica rice in nitrogen-reduced systems exhibited the following order: CK > CDN > DN > MN. Conversely, the taste of cooked rice indicated a preference ranking of CDN > MN > DN > CK. In comparison with CK, the CDN treatment slightly decreased grain yield but significantly improved the milled rice rate, head milled rice rate, cooked rice taste quality (including taste, appearance and comprehensive) and rice starch viscosity parameters (peak viscosity, trough viscosity, final viscosity and breakdown), at the same time as reducing the chalkiness rate, chalkiness degree, protein content and setback. CONCLUSION: The findings suggest that implementing a moderate reduction in nitrogen rate, within the context of high-yield cultivation, can enhance the taste quality of rice, albeit with a reduction in yield. Although increased planting density may partially offset the adverse effects on rice yield following nitrogen reduction, it could potentially compromise rice quality. However, the integration of controlled irrigation and increased planting density within a nitrogen-reduced system can synergistically enhance rice processing quality, appearance quality and the cooked rice taste quality, at the same time as sustaining high grain yield. © 2025 Society of Chemical Industry.