Non-destructive measurement of cucumber leaf chlorophyll content by NIR spectroscopy based on simulated annealing algorithm

Leaf chlorophyll content provides valuable information about physiological status of plants. NIR spectroscopy measurement makes it possible to quickly and non-destructively assess the chlorophyll content in leaves. Our objective was to investigate the spectral behavior of the relationship between reflectance and chlorophyll content and to develop a technique for non-destructive chlorophyll estimation in cucumber leaves. Simulated annealing algorithm (SAA) was used to select most efficient wavelength for cucumber leaf chlorophyll content. 24 wave numbers of cucumber leaves spectral were selected by simulated annealing algorithm. With this combination, partial least square (PLS) model was obtained with the correlation coefficient (Rc) of 0.9542, root mean square error of calibration (RMSEC) of 0.165 and the prediction coefficient (Rp) of 0.9397, root mean square error of prediction (RMSEP) of 0.173. The results of the study shows that NIR spectroscopy could used to measure chlorophyll content of cucumber leaves and SAA could improve the simplify and accuracy of chlorophyll models.