Table 3.

Analysis of variance (ANOVA) for the studied traits in Mentha piperita L. plants under different cadmium stress (Factor a) with nanoparticles of TiO₂ sprayed (Factor b).

Source of variation	df	Mean square
		Chl a	Chl b	Total Chl	Carotenoid	PAL activity
Block	2	0.186*	0.111*	0.585*	0.043*	0.003*
a	3	4.402**	0.828**	8.820**	0.241**	92.560**
b	2	0.436**	0.019**	0.615**	0.109**	19.00**
a × b	6	0.058**	0.005**	0.063**	0.010**	8.953**
Error	22	0.001	0.001	0.003	0.0002	0.015

ns, Not significant.

*Significant at the 0.05 probability level.

**Significant at the 0.01probability level.