Objective Green and high-efficiency management practice (GHP) is integrated and established based on nitrogen and phosphorus fertilizer reduction and efficiency enhancement, as well as silicon application for improving yield stability. To clarify the effects of GHP on grain yield, quality, and nitrogen use efficiency of high-quality rice, as well as the performance of this technology in different varieties and different planting seasons, and provide a scientific basis for the large-scale popularization and application.

Method Field experiments were conducted from 2023 to 2024 in Qujiang and Ruyuan Counties of Shaoguan City in Guangdong Province. For double-season rice, the experiment followed a completely randomized block design, testing three crop managements and five high-quality rice varieties. For single-season rice, the experiment was laid out in split-plot design with high-quality rice variety as the main plot and crop management as the subplot, testing two crop managements and two high-quality rice varieties.

Result For double-season rice, the grain yield under GHP and farmer’s crop management practice (FP) were comparable in the early season, whereas the grain yield of GHP was significantly higher than that of FP by 10.3%. Among the five high-quality rice varieties, three of them achieved higher yields under GHP in the early season, while all of them showed increased yields under GHP in the late season. Agronomic N use efficiency, partial factor productivity of applied N fertilizer (PFP_N), and partial factor productivity of applied P fertilizer (PFP_P) under GHP were 33.0%, 25.4%, and 97.6% significantly higher than those of FP in the early season, and 63.9%, 31.5%, and 114.9% significantly higher than those of FP in the late season, respectively. For single-season rice, compared with FP, GHP significantly increased grain yield, PFP_N, and PFP_P by 11.9%, 33.1%, and 155.3% in 2023, and by 15.6%, 34.6%, and 40.4 % in 2024, respectively. Among the three high-quality rice varieties, all of them showed increased yields under GHP, with the differences being significant between GHP and FP for ‘Qingxiangyou 19xiang’ and ‘Taifengyou 208’. In comparison with FP, GHP significantly increased milled rice rate and grain length, and decreased amylose content and alkali extinction value in the single season, but no significant difference was observed between FP and GHP in the early and late seasons of double-season croping pattern.

Conclusion GHP consistently improves yield stability, nitrogen and phosphorus use efficiencies across varieties, cropping seasons and years, and can be used in double- and single-rice cropping systems in North Guangdong.