Abstract:Light is one of the important environmental factors for plant growth and development. An STM32 plant light supplement control system is designed in order to make better use of LED light source for plants in tissue culture room, save energy and improve the efficiency of light supplement. STM32 is used as the microcontroller to design the plant light supplement control center and the control nodes. The control center communicates the instructions and data with the multiple light supplement control nodes, installed in the tissue culture room, through the RS485 communication module. According to the instructions and the light-supplementing parameters, control nodes coordinate each module to work with each other, so as to achieve the light supplement on time, on demand and according to quantity. The experimental results show that this system is environmentally friendly, easy to operate, stable and reliable. It can save energy while replenishing light, thus reducing the seedling raising cost of tissue culture room, which is a reference of supplement light in tissue culture indoor plant.