Laser induced chlorophyll fluorescence lifetime measurement and characteristic analysis for plant drought-stress

A novel fluorescence lidar technique using plant fluorescence lifetime is presented to evaluate the living status for plant growth, the environmental monitoring, and so on. A 532 nm laser is used as excitation source for detecting long-range plant condition, and fluorescence signals are displayed by oscilloscope. The fluorescence lifetime can be calculated from phase plane and iterative convolution method. Phase plane method can calculate the estimated value of fluorescence lifetime by fitting the phase plane line. And iterative convolution method is used to improve the accuracy of fluorescence lifetime. The system was designed to measure the chlorophyll fluorescence lifetime. The analysis show that the test error of this method is less than 1.5 %, the method proved to be a high accuracy and real-time monitoring technology, and the correspondence between the plant chlorophyll fluorescence lifetime and the growth is obtained by repeated experiments. These characteristics show that the technique has large application potential for plant condition prediction.