Table 2.

The F_v/F_max, secondary metabolites, relative growth rate (RGR), and leaf area index (LAI) of the nasturtium plants grown under different light periods, but with the same daily light integral (DLI), at 7, 14, and 21 DAT in Experiment 1.

Parameter	Unit	DAT	Treatment z				Difference (%) y	T-Test x p-Value
			T16-300		T24-200
Fv/Fmax	(ratio)	14	0.828	a	0.836	a	1.0	0.234
		21	0.841	a	0.820	a	−2.6	0.020
Antioxidant capacity	(mg TE g−1 leaf FW)	14	1.654	a2*	2.316	a1*	40	5 × 10−5
		21	1.356	b	2.003	b	48	3 × 10−4
Total phenolic content	(mg GAE g−1 leaf FW)	14	2.041	a	2.251	a	10	0.040
		21	2.081	a	2.396	a	15	0.056
RGR	(g g−1 day)	7	0.20	a	0.24	a3*	19	0.015
		14	0.22	a3*	0.24	a	11	6 × 10−4
		21	0.18	b	0.19	b	5	0.038
LAI	(m2 m−2)	7	0.75	c	1.16	c	55	0.014
		14	4.64	b	5.83	b	26	0.007
		21	6.47	a9*	6.93	a9*	7	0.422

^z For the treatment, T16-300 represents the light period of 16 h per day, with a light intensity at 300 µmol m⁻² s⁻¹. T24-200 represents the light period of 24 h per day, with a light intensity at 200 µmol m⁻² s⁻¹. For each treatment and for each growth parameter, the numbers followed vertically (column-wise comparison) by different alphabet letters are statistically different, and the order of magnitude corresponds to the order of the alphabet, i.e., a > b > c. The signs, ¹*, ²*, ³*, or ⁹*, put after the alphabet ‘a’ at the largest mean for each parameter and each treatment, indicate that the probability of the t-test (for the top three parameters) or of the ANOVA (the multiple comparison by Tukey for the RGR and LAI) is p < 0.05, p < 0.01, p < 0.001, or p < 1.0 × 10⁻¹⁰, respectively. ^y The rate of the difference between T24-20 and T16-300, i.e., ((T24–T16)/T16) *100. ^x Double-sided t-test with unequal variances for the mean difference between the two light period treatments (row-wise comparison). The p-values that are less than p = 0.05 are shown in bold letters.