• A knowledge-guided refinement framework is proposed for late-season rice–weed mapping under canopy closure. • The WeedGraphNet outperformed appearance-only U-Net baselines on late-season UAV imagery • High segmentation accuracy is achieved on held-out tiles, with an overall accuracy of 0.974 and a mean IoU of 0.883. • Strong class-wise performance is obtained, with IoUs of 0.970 (rice), 0.820 (weed), and weed F1-score 0.901.
Ahmad et al. (Fri,) studied this question.