1. Background
  2. Data Collection Methods
  3. Data Quality Control
  4. Summary

Key Concepts for Measurement

Fluorometer Calculated Endpoints - Photochemical quenching (qP)

(Maxwell and Johnson, 2000)

qP = (Fm'-Ft)/(Fm'-F0')

This represents the proportion of PSII reaction centers that are open.

Variables Measured Directly

  1. F0' - light-adapted zero-level fluorescence obtained after turning off photosynthetic light
  2. Fm' - light-adapted maximum fluorescence; obtained after a saturating pulse of light
  3. Ft - fluorescence at a given time, usually at steady-state just before a saturating pulse of light.
Image source: http://www.advancedaquarist.com/2004/7/aafeature