Evaluation of a SPAD-502 Plus Chlorophyll Meter to Estimate Chlorophyll Content in Leaves with Interveinal Chlorosis

The portable chlorophyll (Chl) meter SPAD-502 Plus (Konica Minolta Optics, Japan) is one of the most commonly used diagnostic tools for rapid and nondestructive estimation of Chl content in leaves of crops and tree species. The aim of this work was to evaluate the performance of a SPAD-502 Plus to estimate the content of Chl a , Chl b , and Chl ( a + b ) in Solanum lycopersicum L. leaves with mottled, interveinal chlorosis induced by continuous lighting. The results have shown positive correlation between the Chl content index (CCI) and contents per unit leaf area (mg/cm 2 ) of Chl a ( R 2 = 0.89), Chl b ( R 2 = 0.79), Chl ( a + b ) ( R 2 = 0.90) and between CCI and content per unit leaf mass (mg/g) of Chl a ( R 2 = 0.88), Chl b ( R 2 = 0.78), Chl ( a + b ) ( R 2 = 0.89), suggesting that the portable Chl meter SPAD-502 Plus can be an effective tool for nondestructive estimation of Chl content in leaves with mottled, interveinal chlorosis. The accuracy of SPAD-502 Plus Chl meter tends to be higher for estimating Chl content per unit leaf area. Non-linear regressions were successfully used for estimating Chl content from SPAD measurements.