Table II.

Photosynthetic characteristics of YL and ML of wild type and npq1 Arabidopsis determined by Chl fluorometry and photoacoustics before and after high-light stress (3 d at 1,500 μmol m⁻² s⁻¹)

Treatment	Fluroescence (ΦPSII)	Photoacoustics
		ΦO2a	ESb
Control
WT ML	0.69 ± 0.01	2.39 ± 0	20 ± 3
WT YL	0.69 ± 0.01	2.31 ± 0.15	17 ± 4
npq1 ML	0.68 ± 0.02	2.59 ± 0.12	22 ± 5
npq1 YL	0.68 ± 0.02	1.87 ± 0.25	18 ± 2
Light treated
WT ML	0.60 ± 0.09	2.09 ± 0.41	16 ± 5
WT YL	0.65 ± 0.02	2.55 ± 0.25	24 ± 3
npq1 ML	0.36 ± 0.18	1.24 ± 0.33	10 ± 4
npq1 YL	0.61 ± 0.07	2.83 ± 0.45	21 ± 10

Data are mean values of more than three separate experiments ± sd. Measurements were performed in white light at a PPFD of 100 μmol m⁻² s⁻¹.

^a Φ_O2, Quantum yield of oxygen evolution. 

^b ES, Photochemical energy storage.