Comparing SPAD and atLEAF values for chlorophyll assessment in crop species

Zhu, J., Tremblay, N. and Liang, Y. 2012. Comparing SPAD and atLEAF values for chlorophyll assessment in crop species. Can. J. Soil Sci. 92: 645-648. This research had the objective of determining whether a new light transmittance meter, the atLEAF, could be used as a less expensive alternative to the SPAD meter. Both meters measure transmittance through leaf surfaces in wavelengths associated with chlorophyll, and both provide an indirect method for determining the nitrogen status of crop canopies. The current study compared SPAD and atLEAF values under different conditions and for six crop species (canola, wheat, barley, potato and corn). The results indicated strong correlations among laboratory leaf chlorophyll (Chl) content, SPAD values, and atLEAF values. Equivalent performances were observed for SPAD and atLEAF values in different environments regardless of crop species. Therefore, the atLEAF Chl meter can be used as an inexpensive alternative to the SPAD-502 meter.