Iron is an essential element for plant growth and development.Deficiency and excess of iron will result in the disturbance of plant growth and development.Therefore,the iron uptake and homeostasis is tightly regulated in plants.We used Arabidopsis as a model plant of strategy Ⅰ plants(all dicots and nongrass monocots)and intensively studied the molecular regulation mechanism of iron uptake and homeostasis during the past decade.FER,encoding a bHLH protein,was firstly confirmed to be a regulatory gene involved in the control of iron uptake and homeostasis in tomato.