The normalized difference spectral index (NDSI) was used to determine significant wavebands that showed the best correlation with leaf ozone injury. The correlation coefficient (r) between NDSI and OIP were ranged from to 1. Normalized difference spectral index, NDSI [R564,R568], and NDSI[R558,R573] were identified as the best Pearson’s correlation with leaf ozone injury percentage with correlation coefficient more than . |