Protective effect exerted by soil phosphorus on soybean subjected to arsenic and fluoride

Figures & data

Table 1. Factors, treatments and As and F concentrations.

Factors		Soils and As and F concentrations
1	P content	P−: 8 mg P kg^−1	P+: 21 mg P kg^−1
2	As content	Low: 10 mg As kg^−1; Medium: 50 mg As kg^−1; High: 100 mg As kg^−1	Low: 10 mg As kg^−1; Medium: 50 mg As kg^−1; High: 100 mg As kg^−1
	F content	Low: 160 mg F kg^−1; Medium: 250 mg F kg^−1; High: 500 mg F kg^−1	Low: 160 mg F kg^−1; Medium: 250 mg F kg^−1; High: 500 mg F kg^−1
	As and F content	Low: 10 mg As kg^−1 + 160 mg F kg^−1; Medium: 50 mg As kg^−1 + 250 mg F kg^−1; High: As + F: 100 mg As kg^−1 + 500 mg F kg^−1	Low: 10 mg As kg^−1 + 160 mg F kg^−1; Medium: 50 mg As kg^−1 + 250 mg F kg^−1; High: As + F: 100 mg As kg^−1 + 500 mg F kg^−1
	Control	Soil P−, with the background As and F concentrations	Soil P+, with the background As and F concentrations

Experiments were carried out as described in the ‘Materials and methods’ section.

Table 2. Determination of TBARS on soybean roots and leaves treated with low, medium and high As and/or F concentration with both P conditions.

		TBARS (malondialdehyde nmols/g FW)
		Soil P+		Soil P−
Treatment		Roots	Leaves	Roots	Leaves
Control		35 ± 3 aA	50 ± 5 aA	38 ± 5 aA	45 ± 3 aA
As	Low	76 ± 5 bA	75 ± 6 bA	60 ± 5 bB	100 ± 8 bC
	Medium	73 ± 6 bB	75 ± 7 bA	105 ± 8 bB	102 ± 7 bB
	High	140 ± 8 bA	140 ± 10 bA	150 ± 10 bA	175 ± 11 bB
F	Low	70 ± 5 bA	69 ± 7 bA	55 ± 5 bA	70 ± 6 bA
	Medium	69 ± 6 bA	68 ± 6 bA	65 ± 8 bA	80 ± 6 bB
	High	69 ± 5 bA	69 ± 7 bA	59 ± 7 bA	100 ± 9 bB
As + F	Low	75 ± 8 bA	73 ± 7 bA	50 ± 5 bB	60 ± 4 bB
	Medium	100 ± 5 bA	75 ± 5 bB	102 ± 9 bA	110 ± 9 bA
	High	115 ± 9 bA	140 ± 6 bB	125 ± 10 bA	170 ± 12 bC

Experiments were carried out as described in the ‘Materials and methods’ section. Data are mean values of three independent experiments ± S.E. Each value represents three replicates. Different lowercase letter indicates significant differences (p < 0.05) within columns. Different capital letter indicates significant differences (p < 0.05) within rows, between roots or leaves in Soil P+ and Soil P−, according to the Tukey’s multiple range test.

Figure 1. Chlorophyll content on soybean leaves treatment with low, medium and high As and/or F concentration with both P conditions. Experiments were carried out as described in the ‘Materials and methods’ section. Data are mean values of three independent experiments ± S.E. Each value represents three replicates. Different lowercase letters within columns indicate significant differences with respect to controls (p < 0.05). Different capital letters within rows indicate significant differences between roots or leaves in Soil P+ and Soil P−(p < 0.05), according to the Tukey’s multiple range test.

Table 3. Glutathione content on soybean leaves treated with low, medium and high As and/or F concentration with both P conditions.

		Glutathione content (pmols/g FW)
		Soil P+		Soil P−
Treatment		Roots	Leaves	Roots	Leaves
Control		160 ± 13 aA	350 ± 20 aA	180 ± 15 aA	350 ± 20 aA
As	Low	106 ± 11 bA	200 ± 16 bA	100 ± 8 bA	208 ± 18 bA
	Medium	106 ± 8 bB	201 ± 17 bB	80 ± 8 bA	102 ± 7 cA
	High	40 ± 5 cA	90 ± 10 cA	40 ± 6 bA	77 ± 8 cA
F	Low	155 ± 11 aB	250 ± 7 bA	101 ± 15 bA	250 ± 16 bA
	Medium	150 ± 12 aB	230 ± 12 bB	95 ± 8 bA	200 ± 16 bA
	High	90 ± 6 bA	184 ± 7 bA	86 ± 7 bA	191 ± 11 bA
As + F	Low	52 ± 8 cC	204 ± 21 bB	90 ± 5 bA	298 ± 14 bA
	Medium	50 ± 9 cA	202 ± 18 bA	52 ± 7 cA	195 ± 14 bA
	High	38 ± 9 cA	140 ± 10 cB	41 ± 12 cA	85 ± 8 cA

Experiments were carried out as described in the ‘Materials and methods’ section. Data are mean values of three independent experiments ± S.E. Each value represents three replicates. Different lowercase letters indicate significant differences (p < 0.05) within columns, with respect to controls. Different capital letters within rows indicate significant differences between roots or leaves in Soil P+ and Soil P−(p < 0.05), according to the Tukey’s multiple range test.

Figure 2. Determination of CAT activity on soybean roots and leaves’ treatment with low, medium and high As and/or F concentration with both P conditions. Experiments were carried out as described in the ‘Materials and methods’ section. Data are mean values of three independent experiments ± S.E. Each value represents three replicates. Different lowercase letters within columns indicate significant differences with respect to controls (p < 0.05). Different capital letters within rows indicate significant differences between roots or leaves in Soil P+ and Soil P−(p < 0.05), according to the Tukey’s multiple range test.

Figure 3. Determination of SOD activity on soybean roots and leaves’ treatment with low, medium and high As and/or F concentration with both P conditions. Experiments were carried out as described in the ‘Materials and methods’ section. Data are mean values of three independent experiments ± S.E. Each value represents three replicates. Different lowercase letters within columns indicate significant differences with respect to controls (p < 0.05). Different capital letters within rows indicate significant differences between roots or leaves in Soil P+ and Soil P−(p < 0.05), according to the Tukey’s multiple range test.

Figure 4. Determination of GPOX activity on soybean roots and leaves’ treatment with low, medium and high As and/or F concentration with both P conditions. Experiments were carried out as described in the ‘Materials and methods’ section. Data are mean values of three independent experiments ± S.E. Each value represents three replicates. Different lowercase letters within columns indicate significant differences with respect to controls (p < 0.05). Different capital letters within rows indicate significant differences between roots or leaves in Soil P+ and Soil P−(p < 0.05), according to the Tukey’s multiple range test.