Table 3.

Means of nutrients content in mint leaves affected by biochar and chemically modified biochars under fluoride and cadmium toxicities.

Toxicity	Soil treatments	Nitrogen	Phosphorous	Potassium	Calcium	Magnesium	Iron	Zinc
		mg g-1DW
Non-toxic	Non-biochar	33.9 ± 0.78 a	21.9 ± 0.27 a	34.6 ± 1.26 c	11.2 ± 0.22 b	8.1 ± 0.19 c	0.83 ± 0.03 c	0.59 ± 0.02 b
	Biochar	35.2 ± 0.51 a	22.4 ± 0.52 a	39.9 ± 0.66 b	12.9 ± 0.66 a	9.1 ± 0.18 b	0.98 ± 0.09 b	0.68 ± 0.04 a
	Biochar-H2O2	34.1 ± 1.23 a	22.4 ± 0.34 a	42.8 ± 0.89 a	13.4 ± 0.65 a	9.9 ± 0.22 a	1.10 ± 0.08 a	0.69 ± 0.05 a
	Biochar- H3PO4	34.0 ± 0.89 a	22.0 ± 0.61 a	43.2 ± 0.92 a	13.6 ± 0.78 a	9.8 ± 0.22 ab	1.10 ± 0.08 a	0.71 ± 0.04 a
	Biochar-KOH	34.1 ± 0.66 a	22.1 ± 0.22 a	41.5 ± 0.83 ab	13.3 ± 0.92 a	9.9 ± 0.20 a	0.95 ± 0.05 b	0.68 ± 0.04 a
Fluoride	Non-biochar	21.9 ± 0.45 f	9.1 ± 0.21 i	19.2 ± 1.11 hi	5.7 ± 0.30 hi	3.9 ± 0.16 h	0.36 ± 0.06 h	0.25 ± 0.05 hi
	Biochar	24.7 ± 0.88 cde	12.2 ± 0.26 fg	23.6 ± 1.05 defg	7.0 ± 0.21 f	5.0 ± 0.22 g	0.54 ± 0.07 g	0.34 ± 0.03 fg
	Biochar-H2O2	26.4 ± 0.98 bc	14.3 ± 0.33 cd	25.1 ± 0.83 de	7.9 ± 0.16 de	5.8 ± 0.21 def	0.57 ± 0.08 efg	0.44 ± 0.03 cd
	Biochar- H3PO4	26.9 ± 0.46 b	14.5 ± 0.37 bcd	26.0 ± 0.62 d	8.6 ± 0.35 cd	6.1 ± 0.19 de	0.69 ± 0.03 de	0.47 ± 0.02 c
	Biochar-KOH	25.2 ± 0.76 bcd	14.4 ± 0.27 bcd	23.8 ± 0.51 efg	8.1 ± 0.38 cde	5.8 ± 0.18 def	0.68 ± 0.08 de	0.49 ± 0.07 c
Cadmium	Non-biochar	18.6 ± 0.92 g	10.3 ± 0.16 h	15.7 ± 0.88 j	5.1 ± 0.23 i	3.6 ± 0.33 h	0.35 ± 0.08 h	0.15 ± 0.03 j
	Biochar	23.0 ± 0.72 ef	12.0 ± 0.28 fg	20.8 ± 1.07 gh	6.1 ± 0.36 h	5.7 ± 0.24 efg	0.59 ± 0.05 efg	0.37 ± 0.04 ef
	Biochar-H2O2	24.0 ± 0.82 de	13.0 ± 0.43 ef	22.9 ± 1.21 efg	6.2 ± 0.41 ghi	6.2 ± 0.27 de	0.68 ± 0.03 de	0.48 ± 0.05 c
	Biochar- H3PO4	25.1 ± 0.79 bcd	13.9 ± 0.57 cde	23.9 ± 1.12 def	7.0 ± 0.25 f	6.4 ± 0.23 d	0.75 ± 0.04 cd	0.49 ± 0.06 c
	Biochar-KOH	25.2 ± 0.80 bcd	13.7 ± 0.60 de	23.7 ± 1.22 defg	6.9 ± 0.17 fg	6.3 ± 0.24 de	0.73 ± 0.05 cd	0.40 ± 0.07 de
Fluoride + Cadmium	Non-biochar	21.3 ± 0.69 f	11.3 ± 0.25 gh	18.1 ± 0.63 ij	6.1 ± 0.18 h	3.8 ± 0.24 h	0.40 ± 0.03 h	0.20 ± 0.03 ij
	Biochar	24.4 ± 0.73 de	13.8 ± 0.28 cde	21.2 ± 0.89 fgh	7.7 ± 0.23 e	5.1 ± 0.12 fg	0.55 ± 0.04 fg	0.29 ± 0.03 gh
	Biochar-H2O2	25.0 ± 0.39 bcd	14.8 ± 0.37 bcd	23.5 ± 0.82 defg	8.7 ± 0.26 c	5.6 ± 0.23 efg	0.58 ± 0.05 efg	0.38 ± 0.04 ef
	Biochar- H3PO4	25.8 ± 0.46 bcd	15.0 ± 0.28 bc	22.8 ± 0.72 efg	8.0 ± 0.28 cde	6.2 ± 0.24 de	0.68 ± 0.05 de	0.41 ± 0.05 de
	Biochar-KOH	25.9 ± 0.67 bcd	15.3 ± 0.48 b	23.6 ± 0.59 defg	8.0 ± 0.19 cde	6.3 ± 0.28 de	0.66 ± 0.04 def	0.40 ± 0.03 de

Data represents the average of three replicates (n=3) ± standard error. Different letters in each column indicate significant difference by Tukey HSD test at p ≤ 0.05. DW, Dry weight.