Table 3.

Temperature (TP, °C) at which fluorescence yield enhancement occurs in several Arabidopsis lines. Plants were grown at 17°C or 29°C and fluorescence was analyzed continuously using an OSI systems fluorometer during heating at 0.75 °C min^-1, as described in methods. TP is the transition point temperature corresponding to 50% of the maximal quantum yield due to leaf heating. Values are the means ± SE on six determinations conducted on two different plants for 17°C-grown plants and four determinations for 29°C-grown plants. Asterisks indicate significant differences from the value obtained for wild-type plants, * P < 0.05; ** P < 0.01. ND, not determined.

	17°C-grown		29°C-grown
Line	TP (°C)	°C above WT	TP (°C)
WT	42.7 ± 0.21	---	44.8 ± 0.9
fad6	45.0 ± 0.42 **	2.2	44.9 ± 0.5
act1	44.2 ± 0.32 **	1.5	44.2 ± 0.7
fad5	44.0 ± 0.26 *	1.2	44.2 ± 0.7
fad7 fad8	43.8 ± 0.64	1.0	ND
act1 fad6	43.0 ± 0.18	0.2	ND
act1++	43.0 ± 0.53	0.2	ND