## 3 Result
### The Effect of Different N Management Practices on Grain Filling Characteristics  
The grain filling rate of each treatment after antibesis showed a single peak curve (Figure 7). With the increase of N application rate, the peak appearance time was delayed, and the peak value was decreased. The results of logistic equation fitting showed that as the N application rate increased, the time required to reach the maximum grain filling rate (T\({}_{\rm max}\)), the duration of grain filling (T), and the active grain filling period (D) all increased (Table 3). There were no significant differences in T\({}_{\rm max}\), T, maximum grain-filling rate (V\({}_{\rm max}\)), and D between the T and F treatments during the two wheat seasons under N0 and N3 treatments. Under N1, the V\({}_{\rm max}\) of the F treatment was significantly higher than that of T only in 2022-2023. The T\({}_{\rm max}\), T, and D of F treatment under N2 were significantly increased compared to that of T. \begin{table}
\begin{tabular}{c c c c c} \hline \hline \multirow{2}{*}{**Year**} & \multirow{2}{*}{**Treatment**} & \multirow{2}{*}{**RDM**} & **Contribution of** & \multirow{2}{*}{**DMA**} & **Contribution of** \\  & & & **RDM to Grain** & & **DMA to Grain** \\ \hline \multirow{8}{*}{2022–2023} & & **(kg ha\({}^{-1}\))** & **(\%)** & **(kg ha\({}^{-1}\))** & **(\%)** \\ \cline{2-5}  & TN0 & 2277.04 \(\pm\) 18.99 f & 34.43 \(\pm\) 0.88 b & 4338.15 \(\pm\) 147.02 e & 65.57 \(\pm\) 0.88 d \\  & FN0 & 2286.84 \(\pm\) 69.87 f & 34.78 \(\pm\) 1.39 b & 4289.16 \(\pm\) 133.47 e & 65.22 \(\pm\) 1.39 d \\  & TN1 & 2790.68 \(\pm\) 29.46 e & 35.65 \(\pm\) 0.72 a & 5038.21 \(\pm\) 118.75 d & 64.35 \(\pm\) 0.72 e \\  & FN1 & 2890.89 \(\pm\) 4.67 d & 35.81 \(\pm\) 0.77 a & 5185.40 \(\pm\) 177.50 d & 64.19 \(\pm\) 0.77 e \\  & TN2 & 3110.27 \(\pm\) 16.80 b & 32.74 \(\pm\) 0.07 c & 6388.96 \(\pm\) 38.92 c & 67.26 \(\pm\) 0.07 c \\  & FN2 & 3214.79 \(\pm\) 27.11 a & 30.47 \(\pm\) 0.42 d & 7336.88 \(\pm\) 93.44 a & 69.53 \(\pm\) 0.42 ab \\  & TN3 & 2976.45 \(\pm\) 7.76 c & 31.02 \(\pm\) 0.33 d & 6618.68 \(\pm\) 106.76 b & 68.98 \(\pm\) 0.33 b \\  & FN3 & 3014.96 \(\pm\) 55.07 c & 29.63 \(\pm\) 0.30 e & 7161.22 \(\pm\) 50.16 a & 70.37 \(\pm\) 0.30 a \\ \hline \multirow{8}{*}{2023–2024} & TN0 & 2904.39 \(\pm\) 46.72 f & 43.13 \(\pm\) 1.09 a & 3830.28 \(\pm\) 110.29 g & 56.87 \(\pm\) 1.09 d \\  & FN0 & 2932.01 \(\pm\) 37.69 f & 42.99 \(\pm\) 0.83 a & 3888.50 \(\pm\) 82.18 g & 57.01 \(\pm\) 0.83 d \\  & TN1 & 3166.92 \(\pm\) 35.08 e & 34.33 \(\pm\) 1.01 b & 6057.01 \(\pm\) 65.36 f & 65.67 \(\pm\) 1.01 c \\  & FN1 & 3324.37 \(\pm\) 46.22 d & 34.62 \(\pm\) 1.04 b & 6279.48 \(\pm\) 139.88 e & 65.38 \(\pm\) 1.04 c \\  & TN2 & 3654.47 \(\pm\) 32.62 b & 33.98 \(\pm\) 0.95 b & 7097.85 \(\pm\) 81.64 d & 66.02 \(\pm\) 0.95 c \\  & FN2 & 3746.81 \(\pm\) 46.83 a & 30.59 \(\pm\) 0.47 d & 8501.03 \(\pm\) 86.10 a & 69.41 \(\pm\) 0.47 a \\  & TN3 & 3405.56 \(\pm\) 48.46 c & 31.61 \(\pm\) 0.64 c & 7370.20 \(\pm\) 146.46 c & 68.39 \(\pm\) 0.64 b \\  & FN3 & 3420.38 \(\pm\) 13.56 c & 30.69 \(\pm\) 1.05 d & 7725.89 \(\pm\) 179.07 b & 69.31 \(\pm\) 1.05 a \\ \hline \multirow{8}{*}{2023–2024} & F-value & & & & \\       & R & 31.71 ** & 11.51 * & 139.15 ** & 11.51 * \\ \cline{1-1} \cline{2-5}  & M & 842.54 ** & 180.07 ** & 1585.25 ** & 180.07 ** \\ \cline{1-1} \cline{2-5}  & R \(\times\) M & 4.98 * & 6.94 * & 44.82 ** & 6.94 * \\ \hline \hline \end{tabular}  
* N0, no N application; N1, N application rate of 150 kg ha\({}^{-1}\); N2, N application rate of 210 kg ha\({}^{-1}\); N3, N application rate of 270 kg ha\({}^{-1}\); T, traditional fertilization method; F, tertigation; R, N rates; M, N application methods. Values followed by a different small letter were significantly different at \(p\leq\) 0.05. Data were presented as mean values \(\pm\) SD (n = 3).
* Indicates significance at \(p\) level of 0.05. *
* indicates significance at \(p\) level of 0.01.  
\end{table}