Integrating critical nitrogen dilution curve, nitrogen nutrition index, and yield response modelling to optimize nitrogen requirement in spring wheat - Koushik Bag; Vinay Kumar Sehgal; Rajkumar Dhakar; Kalikinkar Bandyopadhyay; Manoj Shrivastava; Tapan Jyoti Purakayastha; Soumen Pal (Plant Physiology Reports, 2026)