Elemental Assessments in Paddy Soil for Geographical Traceability of Rice from Peninsular Malaysia

doi:10.1016/j.rsci.2023.04.004

Abstract

Abstract:

This investigation aimed to establish the geographical traceability of Malaysian rice by assessing the elemental composition in paddy soil. Multi-element determination in combination with a chemometric approach was applied to evaluate the elemental concentrations of paddy soil from granaries cultivated with the same rice variety and to assess the relationship between elements in the soil and rice (SAR) system. A total of 29 elements (aluminum, arsenic, barium, bromine, calcium, chlorine, cobalt, chromium, cesium, europium, iron, gallium, hafnium, potassium, lanthanum, lutetium, magnesium, manganese, sodium, rubidium, antimony, scandium, samarium, thorium, titanium, uranium, vanadium, ytterbium and zinc) were successfully determined in paddy soil from Kedah, Selangor and Langkawi by neutron activation analysis. A significant difference (P < 0.05) between 18 elements in the soil samples was obtained. The chemometric approaches of principal component and linear discriminant analyses demonstrated clear discrimination and highly corrected classification (100%) of the soil samples. A high classification (98.1%) was also achieved by assessing 10 elements (aluminum, arsenic, bromine, chlorine, potassium, magnesium, manganese, sodium, rubidium and zinc), which similarly applied to rice geographical origin determination. Similar elements in SAR were also observed for differences in the pattern of correlation and bioaccumulation factor between the granaries. Furthermore, the generalized Procrustes analysis showed a 98% consensus between SAR and clear differences between the studied regions. The canonical correlation analysis demonstrated a significant correlation between the chemical profile of SAR (r² = 0.88, P < 0.001). Therefore, the current work model provides a reliable assessment to establish rice provenance.

Key words: soil, rice, multi-element, correlation, geographical origin

Nazaratul Ashifa Abdullah Salim, Norlida Mat Daud, Julieta Griboff, Abdul Rahim Harun. Elemental Assessments in Paddy Soil for Geographical Traceability of Rice from Peninsular Malaysia[J]. Rice Science, 2023, 30(5): 486-498.

Figures/Tables 9

References 72

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Element	Certified value (mg/kg)		Recovery (%)	RSD ^c (%)	LOD ^d (mg/kg)
NRC PACS-2 marine sediment
Al	66 200 ± 3 200	66 700 ± 2 200	101	3.3	150
As	26.2 ± 1.5	25.5 ± 1.8	97	6.9	0.5
Cl	30 000 ^a	30 000 ± 900	99	3.1	40
K	12 400 ± 11	12 700 ± 600	102	4.8	1 000
Mg	14 700 ± 1 300	14 600 ± 900	100	6.5	800
Mn	440 ± 19	440 ± 15	100	3.4	10
Sb	11.3 ± 2.6	11.8 ± 0.7	104	6.1	0.5
NIST 1646a estuarine sediment
Ba	210^a	210 ± 20	102	11.0	10
Ca	5 190 ± 200	5 300 ± 200	102	4.4	300
Co	5^a	5.0 ± 0.2	99	3.8	0.1
Fe	20 080 ± 390	20 270 ± 870	101	4.3	10
La	17^a	18 ± 1	105	3.8	0.5
Na	7 410 ± 170	7 730 ± 160	104	2.0	10
Rb	38^a	36 ± 2	95	4.7	10
Ti	4 560 ± 210	4 620 ± 300	101	6.5	50
Zn	48.9 ± 1.6	49.0 ± 3.0	100	6.2	10
IAEA-SL-2 lake sediment
Cr	104 ± 9	100 ± 6	96	6.5	3
Cs	7.0 ± 0.9	7.0 ± 0.2	96	2.8	0.05
Eu	1.6 ± 0.5	1.6 ± 0.2	102	8.4	0.05
Ga	23.7 ± 5.1	24.0 ± 2.0	101	8.4	1.0
Hf	4.2 ± 0.6	4.5 ± 0.2	108	5.0	0.2
Lu	0.54 ± 0.13	0.48 ± 0.10	90	8.7	0.05
Sc	17.3 ± 1.1	16.7 ± 0.7	97	4.0	0.05
Sm	9.25 ± 0.51	9.31 ± 0.26	101	2.8	0.03
Th	14.0 ± 1.0	14.0 ± 0.4	101	2.2	0.2
U	4.02 ± 0.33	4.01 ± 0.37	100	9.2	0.1
V	170 ± 15	170 ± 9	98	5.2	0.1
Yb	3.42 ± 0.73	3.50 ± 0.31	102	8.9	0.15
IAEA soil-7
Br	7.0^a	7.0 ± 0.4	101	5.3	0.5

Element	Certified value (mg/kg)		Recovery (%)	RSD ^c (%)	LOD ^d (mg/kg)
NRC PACS-2 marine sediment
Al	66 200 ± 3 200	66 700 ± 2 200	101	3.3	150
As	26.2 ± 1.5	25.5 ± 1.8	97	6.9	0.5
Cl	30 000 ^a	30 000 ± 900	99	3.1	40
K	12 400 ± 11	12 700 ± 600	102	4.8	1 000
Mg	14 700 ± 1 300	14 600 ± 900	100	6.5	800
Mn	440 ± 19	440 ± 15	100	3.4	10
Sb	11.3 ± 2.6	11.8 ± 0.7	104	6.1	0.5
NIST 1646a estuarine sediment
Ba	210^a	210 ± 20	102	11.0	10
Ca	5 190 ± 200	5 300 ± 200	102	4.4	300
Co	5^a	5.0 ± 0.2	99	3.8	0.1
Fe	20 080 ± 390	20 270 ± 870	101	4.3	10
La	17^a	18 ± 1	105	3.8	0.5
Na	7 410 ± 170	7 730 ± 160	104	2.0	10
Rb	38^a	36 ± 2	95	4.7	10
Ti	4 560 ± 210	4 620 ± 300	101	6.5	50
Zn	48.9 ± 1.6	49.0 ± 3.0	100	6.2	10
IAEA-SL-2 lake sediment
Cr	104 ± 9	100 ± 6	96	6.5	3
Cs	7.0 ± 0.9	7.0 ± 0.2	96	2.8	0.05
Eu	1.6 ± 0.5	1.6 ± 0.2	102	8.4	0.05
Ga	23.7 ± 5.1	24.0 ± 2.0	101	8.4	1.0
Hf	4.2 ± 0.6	4.5 ± 0.2	108	5.0	0.2
Lu	0.54 ± 0.13	0.48 ± 0.10	90	8.7	0.05
Sc	17.3 ± 1.1	16.7 ± 0.7	97	4.0	0.05
Sm	9.25 ± 0.51	9.31 ± 0.26	101	2.8	0.03
Th	14.0 ± 1.0	14.0 ± 0.4	101	2.2	0.2
U	4.02 ± 0.33	4.01 ± 0.37	100	9.2	0.1
V	170 ± 15	170 ± 9	98	5.2	0.1
Yb	3.42 ± 0.73	3.50 ± 0.31	102	8.9	0.15
IAEA soil-7
Br	7.0^a	7.0 ± 0.4	101	5.3	0.5

Element	Concentration (mg/kg)				P value
Element	Kedah (n = 27)	Selangor (n = 20)	Langkawi (n = 6)	Others ^a	P value
Al	77 200 a	83 400 a	79 300 a	42 567, 990 000	0.1914
As	19.8 a	16.3 a	11.3 a	15.6, 16, 6.83	0.4404
Ba	280 a	220 b	330 a	11.5, 190 000, 460	0.0064
Br	3 b	9 a	2c	41, 10	< 0.0001
Ca	4 660 a	4 250 a			0.4844
Cl	89 b	170 a	61 b	91 000, 300	< 0.0001
Co	5 a	4 ab	3 b	3-66, 7.9, 300, 11.3	0.0244
Cr	70 a	64 b	23 c	46-143, 6, 14 000, 59.5	0.0002
Cs	13 a	13 a	27 a	5.06	0.0623
Eu	1.2 a	0.8 b	0.7 b	1.4	< 0.0001
Fe	22 670 a	22 950 a	14 090 b	12 140, 725 000	0.0382
Ga	18.2 a	19.1 a	16.4 a	15.2	0.1646
Hf	7.2 a	6.3 b	10.5 a	6.4	0.0014
K	12 400	13 100	33 800		0.1251
La	45 a	37 b	32 b	27	< 0.0001
Lu	0.43 a	0.37 b	0.56 a	0.37	< 0.0001
Mg	12 500 a	12 800 a	10 500 a		0.1791
Mn	120 b	150 b	223 a	488	0.0060
Na	850 b	1 980 a	3 050 a		< 0.0001
Rb	112 a	124 a	274 a	0-290, 68	0.1924
Sb	2.1 a	1.6 a	1.3 a	410	0.0632
Sc	12.3 a	11.4 a	6.7 b	11.7	0.0006
Sm	7.98 a	6.39 b	7.22 ab	4.6	0.0004
Th	26 a	24 a	23 a	9.2	0.3016
Ti	4510 a	3 470 b	3 670 b	7 038	< 0.0001
U	6.69 a	5.63 a	9.58 a	3 100, 3	0.0876
V	82 a	74 ab	42 b	55-205, 31.6, 5 200, 129	0.0059
Yb	3.45 a	3.07 b	4.33 a	2.6	0.0022
Zn	62.3 b	78.8 a	75.8 ab	0-92, 21.9, 310 000, 70	0.0049

Element	Concentration (mg/kg)				P value
Element	Kedah (n = 27)	Selangor (n = 20)	Langkawi (n = 6)	Others ^a	P value
Al	77 200 a	83 400 a	79 300 a	42 567, 990 000	0.1914
As	19.8 a	16.3 a	11.3 a	15.6, 16, 6.83	0.4404
Ba	280 a	220 b	330 a	11.5, 190 000, 460	0.0064
Br	3 b	9 a	2c	41, 10	< 0.0001
Ca	4 660 a	4 250 a			0.4844
Cl	89 b	170 a	61 b	91 000, 300	< 0.0001
Co	5 a	4 ab	3 b	3-66, 7.9, 300, 11.3	0.0244
Cr	70 a	64 b	23 c	46-143, 6, 14 000, 59.5	0.0002
Cs	13 a	13 a	27 a	5.06	0.0623
Eu	1.2 a	0.8 b	0.7 b	1.4	< 0.0001
Fe	22 670 a	22 950 a	14 090 b	12 140, 725 000	0.0382
Ga	18.2 a	19.1 a	16.4 a	15.2	0.1646
Hf	7.2 a	6.3 b	10.5 a	6.4	0.0014
K	12 400	13 100	33 800		0.1251
La	45 a	37 b	32 b	27	< 0.0001
Lu	0.43 a	0.37 b	0.56 a	0.37	< 0.0001
Mg	12 500 a	12 800 a	10 500 a		0.1791
Mn	120 b	150 b	223 a	488	0.0060
Na	850 b	1 980 a	3 050 a		< 0.0001
Rb	112 a	124 a	274 a	0-290, 68	0.1924
Sb	2.1 a	1.6 a	1.3 a	410	0.0632
Sc	12.3 a	11.4 a	6.7 b	11.7	0.0006
Sm	7.98 a	6.39 b	7.22 ab	4.6	0.0004
Th	26 a	24 a	23 a	9.2	0.3016
Ti	4510 a	3 470 b	3 670 b	7 038	< 0.0001
U	6.69 a	5.63 a	9.58 a	3 100, 3	0.0876
V	82 a	74 ab	42 b	55-205, 31.6, 5 200, 129	0.0059
Yb	3.45 a	3.07 b	4.33 a	2.6	0.0022
Zn	62.3 b	78.8 a	75.8 ab	0-92, 21.9, 310 000, 70	0.0049

Element	Original/ Jackknife	Group	Predicted group membership
Element	Original/ Jackknife	Group	Kedah	Selangor	Langkawi	Overall
Total 27 elements	Original	Kedah Selangor Langkawi	100 0 0	0 100 0	0 0 100	100
Total 27 elements	Jackknife	Kedah Selangor Langkawi	96.3 5.0 16.7	3.7 95.0 0	0 0 83.3	94.3
Ten elements related to rice analysis	Original	Kedah Selangor Langkawi	96.3 0 0	3.7 100 0	0 0 100	98.1
Ten elements related to rice analysis	Jackknife	Kedah Selangor Langkawi	95.6 10.0 16.7	7.4 90 0	0 0 83.3	90.6