August 2022: Calibration and characterisation of four chlorophyll meters

Dear PhotosynQ User,

Welcome to the PhotosynQ community newsletter!

We have the following study by Brown et al. (2022) as our featured project this month. This study compared four chlorophyll meters including MultispeQ for non-destructive estimation of forest leaf chlorophyll concentration. We hope you enjoy reading our selected study and please stay safe and healthy!

Best, PhotosynQ Team

Luke A. Brown, Owen Williams, and Jadunandan Dash

Calibration and characterisation of four chlorophyll meters and transmittance spectroscopy for non-destructive estimation of forest leaf chlorophyll concentration

https://doi.org/10.1016/j.agrformet.2022.109059

Leaf chlorophyll concentration (LCC) is an indicator of plant health and stress status caused by physical factors. That is useful for vegetation management.

Traditional methods of measuring chlorophyll require destructive sampling and laboratory analysis. These methods are time consuming and laborious hindering our ability to make onsite measurements for management. Transmittance-based chlorophyll meters have been developed to circumvent this problem.

Brown et al. (2020) studied four chlorophyll meters including MultispeQ for their ability to measure chlorophyll concentration in comparison to destructively-determined chlorophyll amounts.

Fig 1. The relationship between the outputs of the leaf chlorophyll values given by PhotosynQ's MultispeQ V1.0 and destructively-determined leaf chlorophyll concentration (LCC) for eight forest species.

According to Figures 1 & 2 as well as other figures and tables illustrated in the paper,

once calibrated for the relationship with destructively determined LCC, leaf chlorophyll meters are a reliable tool for measuring Chlorophyll in field conditions.

Fig 2. Overall relationships between transmittance-based indices and destructively-determined LCC in Leaf CHL Plus (a), Konica Minolta SPAD-502+ (b), Opti-Sciences CCM-200 (c), and PhotosynQ MultispeQ V1.0 (d), in the 8 species measured.

This study highlights the value of MultispeQ V1.0 as a tool for non-destructive measurement of leaf chlorophyll concentration quickly, accurately and cost-effectively, the results of which can be extrapolated to be even more useful in the MultispeQ V2.0.