Application of plant canopy analyzer for mature tea (Camellia sinensis L.) bush

A non destructive method using Plant Canopy Analyzer (LAI-2000, LI-COR, Inc.) was applied to estimate a leaf area index (LAI) for mature tea (Camellia sinensis L.) bushes, The LAI estimated by PCA showed a positive correlation (n= 51, r= 0.951, p < 0.0001) with the orthodox stratified clip method using a leaf area meter. A bias was observed, however, with PCA, since an LAI value of 3 was noted with no leaf. The positive LAI observed in the absence of leaves suggests that the PCA method may sense a branch area as a leaf area. Thus the estimation of LAI using PCA does not seem appropriate. When the same methodology was applied for total weight of a bush, a better correlation was found with PCA (n= 51, r= 0.973, p < 0.0001) than LAI. Thus the PCA appears to be a method of choice for measuring the total weight of a tea bush.