Abstract:In order to realize realtime feedback control for plant supplementary lighting based on the plant growth status, the LED lighting control system based on the FluorMonitor chlorophyll fluorescence sensor was designed. By the SDI-12 and MODBUS communication protocols, the parameters of chlorophyll fluorescence, light intensity and temperature acquisition were realized. According to the measurement process and acquisition cycle of chlorophyll fluorescence parameters of Ft, Fm and Yield, the automatic acquisition mode and manual acquisition mode were designed. Using the pulsewidth modulation (PWM) control mode, the LED light intensity control model was designed to realize the plant lighting accuracy control, and the display of light, temperature and chlorophyll fluorescence parameters and humancomputer interaction were realized through the design of manmachine interface. The supplementary lighting control experiment for lettuce was carried out. The results showed that the LED lighting control system based on chlorophyll fluorescence sensor can realize the stable control of light intensity, ETR and Yield. The system can improve the light utilization efficiency of lettuce, and the lighting realtime feedback control based on plant growth status was realized.