From Growth Dynamics to Agronomic Decisions: A Conceptual Framework for Diagnosing Limiting Processes in Crop Productivity

Crop productivity emerges from interacting processes of resource capture, biomass production, allocation, and yield formation. Final yield alone cannot identify which process limited production, when the limitation occurred, or whether additional inputs would improve performance. This narrative conceptual review synthesizes the foundational and recent literature selected thematically to cover the main physiological and agronomic processes linking crop growth with yield formation and management, including resource capture and biomass production, root–shoot coordination, source–sink relations, yield formation, productive potential, resource-use efficiency, and agronomic intervention. Similar yields can arise from different physiological pathways and therefore require different interventions, while root–shoot allocation and harvest index are context-dependent indicators rather than universal optimization targets. Yield potential should be defined for a genotype × environment × crop-cycle duration combination and used as a reference for diagnosing yield gaps. Sequential measurements can identify when deviations in crop development emerge and, when considered together with complementary crop, soil, environmental, and management indicators, can help distinguish among the processes that may be responsible. We propose a decision framework based on diagnosis, intervention, verification, and trade-off assessment, in which management is justified when it alleviates the identified limiting process while maintaining resource-use efficiency. This framework moves crop analysis from retrospective description toward process-based decision support for more efficient and sustainable agronomic management.