System and method for portable non-destructive detecting plant pigment in fields

The portable non-destructive plant pigment detecting system includes three wavelength spectral measurement device with oppositely set light source and detector, neutralized reference sample or leaf to be measured, micro controller connected to the light source and the detector, serial port circuit connected electrically to the micro controller, and display and keyboard connected electrically to the micro controller too. The detection method includes detecting data I0 and I, calculating the fresh leaf transmission T= I/I0 of different wavelengths, and calculating the plant pigment content ChI in the leaf in chemical metering algorithm. Compared with traditional wet chemical method, the present invention has decades times raised efficiency and no production of environment harming matter.