Influence of cultivation practices on the metabolism of cytokinin and its correlation in rice production

Cytokinin (CTK) has an important regulatory effect on plant morphology, physiology, and yield, and is one of the main factors regulating nitrogen absorption, transport, and metabolism. This paper reviews the research progress in nitrogen absorption, transport and metabolism, cytokinin synthesis, transport and signal transduction, etc., focusing on the physiological mechanisms by which CTK and nitrogen collaborate to regulate the root–shoot relationship and its impact on agronomic traits of crops. The synthesis of trans-zeatin (tZ) and trans-zeatin riboside (tZR) is generally regulated by root nitrogen, which is transported them to the sprouts, regulates nitrogen allocation and metabolism, and affects photosynthetic characteristics and yield. In young shoots, nitrogen upregulates the synthesis of isopentenyl, adenine (iP), and iP-nucleoside (iPR) and transports to roots through the phloem, reducing nitrogen uptake and transport, affecting root morphology. Based on this, the role of, CTK in coordinating relationships between source repositories and enhancing injection. We conducted an analysis on how various cultivation methods impact CTK metabolism and its relationship with plant growth. Additionally, we discussed the challenges associated with applying CTK functions to paddy field production and suggested future research directions.