The research was aimed at developing a conceptual model of digital nitrogen management in crops. Cognitive analysis of the knowledge structure in this subject area, conceptual modeling of digital nitrogen management in agrophytocenoses using object-oriented approach and Unified Modeling Language (UML) were used. A detailed system of diagrams was created, encompassing class, process, and interaction diagrams. The model is anchored on three abstract objects: class (7 in total), attribute (32), and inter-class relationships (18), which distribute the main concepts, emphasizing the complexity and multifaceted approaches to digital nitrogen management. The central class is «Agrophytocenosis», which directly interacts with 5 classes and indirectly with 1 class. Attributes are integral to the classes and reflect their specific characteristics. To depict the interaction between the classes and their attributes, four types of relationships are employed in the model: «dependency», «association», «aggregation», and «inner class». In the process diagram of the digital nitrogen management system, two primary subsystems are highlighted: the analysis and planning subsystem and the adjustment subsystem, as well as tools and sources for data acquisition and processing. A distinctive feature of the developed conceptual model is the application of the temporality principle, integrating static and dynamic processes in the digital nitrogen management system within the agrophytocenosis.Subsystems for analysis, planning and adjustment of emerging conditions in the management areas allow ensuring more efficient use of nitrogen fertilizers in crops.The conceptual model is aimed at developing a hardware-software complex for diagnostics of nitrogen nutrition of cultivated plants and management of fertilizer application based on modern digital monitoring and data processing tools.
