The interplay of carbon, nitrogen, and phosphorus in plants: From independent effects to synergistic regulation

Photosynthetic carbon fixation and nitrogen-phosphorus acquisition is fundamental yet tightly interconnected processes that jointly determine crop productivity and nutrient use efficiency. While these processes have traditionally been studied independently, increasing evidence indicates that carbon assimilation, nutrient uptake, and metabolic allocation are coordinated through shared signaling pathways, metabolic nodes, and source-sink regulation. This review systematically summarizes the latest advances in research on how photosynthetic carbon metabolism interacts with N and P uptake across molecular, physiological, and agronomic scales. We highlight key regulatory modules, including transcriptional networks, hormonal signaling, and metabolite-mediated feedbacks, that integrate carbon supply with nutrient demand. Finally, we discuss how this integrative framework can guide molecular breeding and management strategies aimed at improving crop yield and nutrient use efficiency under resource limited and ever-changing environmental conditions.