Table 2.

Chlorophyll a fluorescence parameters in upper and lower cotyledons of embryos or seedlings developing from control dormant embryos, embryos pre-treated with NO immediately after seed coat removal (NO), and embryos fumigated with NO after 5 days of imbibition in water (5d+NO)

Culture period	Treatment	Cotyledon	Fv/Fm	Fv/F 0
5 days	Control	U	nd	nd
		L	0.43 ± 0.03	0.80 ± 0.04
	NO	U	0.61 ± 0.07*	1.77 ± 0.30*
		L	0.58 ± 0.06	1.50 ± 0.20*
8 days	Control	U	nd	nd
		L	0.48 ± 0.06	0.90 ± 0.10
	NO	U	0.76 ± 0.05*	3.23 ± 0.70*
		L	0.75 ± 0.05	3.20 ± 0.50*
	5d+NO	U	0.49 ± 0.06*	1.29 ± 0.20*
		L	0.54 ± 0.05	1.22 ± 0.20
10 days	Control	U	0.04 ± 0.01	0.05 ± 0.01
		L	0.56 ± 0.07	1.70 ± 0.30
	NO	U	0.55 ± 0.08*	1.23 ± 0.10*
		L	0.55 ± 0.07	1.30 ± 0.10
	5d+NO	U	0.60 ± 0.10*	1.55 ± 0.20*
		L	0.55 ± 0.07	1.30 ± 0.20

Fluorescence was determined at 5th, 8th and 10th day of culture period. Values are mean ± SE of 3 experiments, nd not detected

Asterisk (*) indicates significance from control at the same time of culture at P ≤ 0.05