Quantitative and qualitative tuning of cytokinin actions for plant growth regulation

Abstract

Cytokinin is a classical phytohormone discovered approximately 65 years ago.　Cytokinin was first shown to promote cell division and subsequently determined to play a key role in regulating a wide variety of aspects in plant growth and development.　Studies of cytokinin biosynthesis and its actions in the past 20 years have revealed a basic frame of cytokinin biosynthesis in plants and some phytopathogens, as well as the biological significance of its structural variations.　These findings have provided valuable information for understanding the mechanisms underlying proper plant growth regulation in response to environmental changes and niche formation strategies of some plant pathogens.