Increased Lodging Risk Offsets Rice ( Oryza sativa L.) Yield From Postponed Nitrogen With Higher Panicle Fertilisation in Southern China

The cultivation strategy of ‘postponed nitrogen with increased panicle fertilization (PNIPF)’ boosts rice yield but the balance between lodging remains unclear. We evaluated three panicle nitrogen ratios (0%, 20% and 40% of total 165 kg N ha −1 ) in two late indica rice varieties ( Meixiangzhan 2 and Taiyou 871 ) to assess this trade‐off. Results demonstrated that: (1) Compared to R 0 , PNIPF to 20% showed no difference on yield, while R 4 raised grain yield by 4.84% and 8.69% but increased lodging index by 30.5% and 35.8% in TY871 and MXZ2. (2) Relative to R 0 , R 4 induced taller plants with elevated center of gravity, reduced culm diameter, diminished culm mechanical strength, and decreased structural carbohydrate content (cellulose −29.2%, lignin −23.8%). The effect of R 2 is weaker than R 4 on plant morphology. (3) Compared to R 0 , R 4 manifested more profound anatomical deterioration than R 2 . (4) Significant variety differences existed; PNIPF exhibited a more profound impact on MXZ2 than TY871 by inferior morphological, physiological and anatomical traits. We recommend limiting panicle nitrogen to below 20% to achieve synergistic improvement of yield and lodging resistance in high‐quality late indica rice production.