*4.5. Electron Transport and JO2*

The electron transport rate was determined using the pulse amplitude modulated fluorometer (OSP1 Fluorometer), according to Guralnick et al. [20]. Samples were taken over the course of the light period beginning at 6:00 in the greenhouse. Intact leaf tissue of well-watered and water-stressed cotyledons were measured [20]. The true rate of O2 evolution (JO2) from Photosystem II activity was calculated, according to the method of Lal and Edwards [35].
