Effects of Illite-Containing Fertilizer Prototypes on Nutrients Uptake and Antioxidant of Lettuce (Lactuca sativa L.)

Ga-Eun Kim, Hye-Sun Lee, Young-Ran Lee, and Jwakyung Sung

doi:10.7745/KJSSF.2023.56.1.027

Preview

Article

Korean Journal of Soil Science and Fertilizer. 28 February 2023. 27-38
https://doi.org/10.7745/KJSSF.2023.56.1.027

Effects of Illite-Containing Fertilizer Prototypes on Nutrients Uptake and Antioxidant of Lettuce (Lactuca sativa L.)

Ga-Eun Kim¹^†

Hye-Sun Lee²^†

Young-Ran Lee²^*

Jwakyung Sung³^*

¹Graduate Student, Department of Crop Science, College of Agriculture, Life and Environment Sciences, Chungbuk National University, Cheongju 28644, Korea

²Researcher, Center for Convergence Bioceramic Materials, KICET, Chungju 28160, Korea

³Professor, Department of Crop Science, College of Agriculture, Life and Environment Sciences, Chungbuk National University, Cheongju 28644, Korea

^{*Corresponding Author}

^†These authors contributed equally to this work.

ABSTRACT

Illite, a clay mineral, contains high levels of K⁺ content to be available by plants. Effect of illite on soil and crops have been reported, but more examples are needed to extend to a variety of crop plants. This study was carried out to investigate the effects of illite-containing prototypes as an alternative fertilizer on nutrient uptake and antioxidant activity of lettuce. Lettuce was grown for 30 days with six different fertilizer treatments (control, NPK, illite, prototype-A, prototype-B, and prototype-C) using acidic nutrients-poor soil (AC-NPS) and alkaline nutrients-rich soil (AK-NRS). The pH adjustment by illite-containing prototypes was not observed from both two soils, AC-NPS and AK-NRS. Prototype-A resulted in an enhancement of total nitrogen content of soil at both AC-NPS and AK-NRS. Total nitrogen of lettuce shoots was remarkably higher in prototype-B and -C at both soils. Illite-only treatment showed the highest level of total ploypenols (19.5 mg g^-1), flavonoids (3.8 mg g^-1) and ABTS (37.2%) in the AC-NPS. Overall, illite-containing prototype B- and -C showed a significant increase not only macro nutrients (nitrogen, calcium and magnesium) but antioxidant activity in the AC-NPS. Accordingly, it is considered that illite-containing prototypes might be an alternative or supplement of chemical fertilizer to promote lettuce growth.

https://static.apub.kr/journalsite/sites/ksssf/2023-056-01/N0230560103/images/ksssf_2023_561_27_F0.jpg

Effect of illite-containing prototypes on total nitrogen and antioxidant ability of lettuce plant.

Keywords

Antioxidant

Illite

Lettuce

Nutrients

Soil

MAIN

Introduction
Materials and Methods
Prototypes containing illite, soil and fertilizer treatment
Growth conditions and sampling
Analysis of soil chemical properties and plant inorganic components
Extraction and measurement of chlorophyll and antioxidant capacity
Statistical analysis
Results and Discussion
Effect of illite-containing prototypes on soil chemical properties
Effect of illite-containing prototypes on lettuce growth
Effect of illite-containing prototypes on chlorophyll and antioxidant capacity of lettuce
Conclusions

Introduction

Crop plants obtain essential nutrients from soil, but soil nutrients are limited. Fertilizers are required to provide essential nutrients to crop plants and improve crop production and quality in modern agriculture (Isherwood, 2000). However, due to the limited nutrient use efficiency of plants, an excess supply of chemical fertilizers has resulted in environmental issues such as groundwater contamination by a leaching and/or runoff and air pollution by en emission. Therefore, the development and use of eco-friendly fertilizers are important to pursue both an improved fertilizer efficiency and reduced release of nutrients.

Clay minerals include inorganic ions such as K⁺, Ca²⁺ and Mg²⁺, which are a nutrient source for crop growth and development, in the interlayer space of particle (Kumari and Mohan, 2021). Despite of the relative lower cations-exchangeable capacity (CEC) compared to other clay minerals like perlite and vermiculite, illite possess higher K⁺ content to be available by plants (Weaver, 1965; Hashemi and Abbaslou, 2016; Paola et al., 2016). There are abundant illite to be used in industrial sectors including agriculture in Yeongdong-gun, Chungbuk province, South Korea (Cho et al., 2007). The main composition of illite is quartz (76%), illite (17%) and feldspar (7%) (Hwang et al., 2016). The effect of illite on soil amendement and crop growth promotion was reported (Barre et al., 2007; Lee et al., 2021), and thus it is required to find much evidence of the effect via extending into various crop plants.

Lettuce (Lactuca sativa L.) is one of leafy vegetables, which is being most extensively produced in the world. It is well known that lettuce shows an antioxidant capacity due to higher phenolic compounds, occupying more than 60% of total antioxidants (Nicolle et al., 2004). The potassium (K) fertilization in wheat production increased antioxidant capacity (Ahanger and Agarwal, 2017), and, additionally, it was reported that K fed by plants led to activate antioxidant metabolism (Ahanger et al., 2017). Illite-containing fertilizers showed a significant positive effect on improvement of soil quality including the effect of improving soil pH and plant growth promotion in tomato plants (Lee et al., 2021). The nutrient content and acidity of the soil can affect crop growth and nutrient content (Choi et al., 2021). Therefore, illite is considered as a valuable source to be used in agricultural area to pursue not only soil amelioration but healthy crop production. However, studies on the effect of illite have been conducted only on some crops, and thus it is required to prove an effect from various crop plants. Based on previous report (Lee et al., 2021), this study tried to develop a variety of illite-containing prototypes as alternative fertilizers and to examine their effects on the growth and antioxidative ability of lettuce plants.

Materials and Methods

Prototypes containing illite, soil and fertilizer treatment

In order to investigate the effects of illite-containing prototypes on pH amendement and plant growth promotion, two types of soil, acidic nutrient-poor soil (AC-NPS) and alkaline nutrient-rich soil (AK-NRS), were used in this work. The experimental soils, AC-NPS and AK-NRS, were obtained from the experiemtal fields of Chungbuk national university (Cheongju) and Galic research center (Danyang), respectively. The detailed information of soil including soil texture is described in Table 1. Illite, a clay mineral, was collected at Youngdong-gun, Chungbuk province (Table 2). Physicochemical properties of illite and three illite-containing prototypes were described in Table 3. The information on all types of illite-cotaining prototypes including the newly developed for the current work was shown in Table 3 and Fig. 1. Illite-containing prototypes are for soil amendment (prototype-A) and plant growth promotion (prototype-B and C). Both prototype-B and -C were manufactured with compound fertilizers, but the materials of the main inorganic fertilizers were different.

The treatments were composed as followed: no-fertilization, NPK, illite, prototype-A, prototype-B, and prototype-C. A dose of inorganic fertilizer (NPK) was determined from soil diagnosis (NIAS, 2017). Nitrogen (N, 188 kg ha^-1), phosphorus (P, 215) and potassium (K, 149) were employed for the AC-NPS, and 74 (N) and 94 (P) were applied for the AK-NRS. The supply of K was ignored due to the surplus K content. Considering the relatively shorter cultivation period (30 days), urea (N), potassium phosphate (P) and potassium chloride (K) were applied as a basal dressing. Illite-containing prototypes were applied with 2,000 kg ha^-1-equivalent as the recommended does of calcareous fertilizer which is a soil conditioner (NIAS, 2017). Inorganic fertilizer (NPK) was not entered into the illite-containing prototype treatments.

Table 1.

Physicochemical properties of experimental soils.

Properties	Unit	Appropriate^† value	AC-NPS^‡	AK-NRS^§
Soil texture	USDA	-	Sandy loam	Loam
pH	1:5, DW	6.5 - 7.0	5.1	8.1
EC	1:5, dS m^-1	≤2	0.2	2.5
OM (TC × 1.724)	g kg^-1	20 - 30	0.82	6.38
TN	wt%	-	0.04	0.31
Avail. P₂O₅	mg kg^-1	250 - 400	4	304
Exch. K	cmol_c kg^-1	0.4 - 0.6	0.2	2.1
Exch. Ca		6.0 - 7.0	0.6	21.3
Exch. Mg		2.0 - 2.5	0.9	4.6
Exch. Na		-	0.2	0.3

^†Refer to the fertilizer use prescriptions standard (NIAS, 2017).

^‡AC-NPS, acidic nutrient-poor soil;

^§AK-NRS, alkaline nutrient-rich soil.

Table 2.

Physiocochemical composition of illite prototypes used in this study.

Physical properties				Mineral contents (%)
Thickness (Å)	Diameter (nm)	Base space (Å)	Particle density (g cm^-3)	SiO₂	Al₂O₃	Fe₂O₃	K₂O	CaO	TiO₂
30	0.1 - 0.3	10	2.6	57.5	23.3	6.76	6.43	0.1	0.38

Table 3.

Composition of various illite-containing prototypes.

Application	Role	Materials	Composition rate (%)
Illite	Main body	Illite (200 mesh)	100
Prototype-A	Enhancement	Bacillus safensis HC42 (3.0 × 10⁹ cfu g^-1)	0.1
	Enhancement	Bacillus subtilis WP (1 × 10¹⁰ cfu g^-1)	0.1
	Main body	Illite (200 mesh)	80
	Binding agent	Starch	18
	Surfactant	FD-100PX	2
	Sum		100
Prototype-B	Inorganic fertilizer	Urea	20
		KH₂PO₄	5
		KCl	9
	Supplement	Amino acid	5
	Main body	Illite (200 mesh)	45
	Binding agent	Starch, Boric acid (H₂BO₃), Molasses	14
	Surfactant	FD-100PX	2
	Sum		100
Prototype-C	Inorganic fertilizer	Urea	18
		MAP (mono ammonium phosphate)	5
		KCl	10
	Main body	Illite (200 mesh)	40
	Supplement	Amino acid	3
	Binding agent	Starch	20
		NK-XG (xanthan gum)	1
		EDTA-FE	1
	Surfactant	FD-100PX	2
	Sum		100

https://static.apub.kr/journalsite/sites/ksssf/2023-056-01/N0230560103/images/ksssf_2023_561_27_F1.jpg

Fig. 1.

Different types of illite-containing prototypes for agricultural use. The detailed composition of each prototypes was described in Table 3.

Growth conditions and sampling

The seed of lettuce (Lactuca sativa L.) was germinated with a commercial nursery soil (128-hole plug tray), and uniformly grown lettuce seedlings (second leaf stage) were transplanted into plastic containers (20 cm width × 30 cm height, 10 kg of soil). Soil and plant samples for further analysis were carefully taken at 30 days after treatment. The treatment was arranged with the completely randomized plot design (n = 6). Leaf length and width were measured from the upper fully expanded leaves.

Analysis of soil chemical properties and plant inorganic components

Soil chemical properties were analyzed with an analytical manual (NIAS, 2000). The soil pH and electrical conductivity (EC) (soil: deionized-distilled (DD) H₂O = 1:5) were measured with a pH and conductivity meter, respectively. Sample pH was measured using the Fisherbrand^TM accumet^TM AB150 pH Benchtop Meters (Fisher Scientific, Loveland, CO, USA) which was calibrated with Thermo Scientific^TM Orion^TM buffer (Fisher Scientific, Loveland, CO, USA) with pH value of 4.01, 7.00 and 10.01. EC was measured using the Thermo Scientific^TM Orion Star^TM A212 Conductivity Benchtop Meter (Fisher Scientific, Loveland, CO, USA), precalibrated with 1,413 and 12,880 µS cm^-1 obtained from Thermo Fisher Orion conductivity standard solution (Fisher Scientific, Loveland, CO, USA). Available phosphate was measured at 720 nm using a UV-visible spectrophotometer (UV 1900i, Shimadzu, Japan). Soil inorganic nitrogen (nitrate and ammonium) was measured with an automatic-nitrogen analyzer (440 nm, Auto analyzer 3, BRAN+LUEBBE, Germany) after extracting with 2 M KCl. Soil exchangeable cations including potassium (K), calcium (Ca) and magnesium (Mg) were measured using ICP (GBC, Integra XL, Australia) after the extraction with 2 M ammonium acetate buffer.

The concentrations of mineral nutrients were analyzed according to the standard method (Lee et al., 2017). The dried plant samples (0.5 g) were wet-digested with a solution (concentrated sulfuric acid including 5 mL of 368 mM salicylic acid), diluted with dd H₂O and used as an analysis samples. Total N was measured with an automatic-nitrogen analyzer (440 nm, Auto analyzer 3, BRAN+LUEBBE, Germany), phosphorus was measured at measured at 470 nm (UV 1900i, Shimadzu, Japan) using a UV-visible spectrophotometer, and cations were measured using ICP (GBC, Integra XL, Australia).

Extraction and measurement of chlorophyll and antioxidant capacity

After the growth investigation, the above-ground lettuce parts were sampled and stored in a cryogenic freezer (-80°C) for analysis of chlorophyll and antioxidant activity. Chlorophyll analysis was followed: a ground fresh sample (0.5 g) was mixed with 50 mL 70% ethanol and stand at 4°C for 24 h. After extracting 2 mL from the mixture, 8 mL acetone was added and measured absorbance at 645 and 663 nm. These values were then used in the calculation of the following (Porra, 2002) :

(Eq. 1)

Chlorophyll a = [(12.3 \times {Abs}_{663 nm}) - (2.69 \times {Abs}_{645 nm})] \times dilution factor

(Eq. 2)

Chlorophyll b = [(22.9 \times {Abs}_{645 nm}) - (4.68 \times {Abs}_{663 nm})] \times dilution factor

Total polyphenols and flavonoids content were analyzed for antioxidant capacities. The 2,2′-azino-bis-3-ethylbenzthiazoline-6-sulphonic acid (ABTS) and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical were measured to evaluate radical scavenging. To measure the antioxidant capacities, the fresh sample was extracted: the ground sample powder (0.5 g) was mixed with 70% ethanol (15 mL) and stirred at 200 rpm for 30 min. After centrifugation and filtration (0.45 µm), the extraction was used analysis.

Total polyphenol was determined using Folin-Ciocalteu’s phenol reagent (Folin and Denis, 1912). The reaction mixture including 250 µL of extraction, 5 mL of 2% Na₂CO₃ and 250 µL of Foline-Ciocalteu reagent reacted in the dark for 30 minutes, and was measured at 750 nm. Gallic acid was used as a standard. Total polyphenol was quantified according to the calibration curve (y = 0.001x + 0.0021, R² = 0.999) in the range of gallic acid 0 - 100 µg mL^-1.

Total flavonoid was measured with Moreno method (Moreno et al., 2000). Extraction solution (500 µL) was mixed with 150 µL of NaNO₂ and 2 mL of deionized-distilled water and stand for 5 min at RT. The 300 µL of 10% AlCl₃ ‧ 6H₂O was added into the reaction mixture and reacted for 6 min. After an addition of 1 mL of 1 M NaOH, the reaction mixsture reacted for 11 min at RT and was measured at 510 nm. Catechin was used as a standard. Total flavonoid was quantified according to the calibration curve (y = 0.0055x + 0.0001, R² = 0.999) in the range of catechin 0 - 100 µg mL^-1.

For the ABTS assay, 7.4 mM ABTS was dissolved in 2.6 mM K₂SO₄. The reaction buffer was incubated for one day at RT in the dark and diluted until the value of absorbance measured 1.0 at 735 nm. According to Re method (Re et al., 1999), the extract (200 µL) was mixed with 4 mL of the reaction solution and reacted for 30 min in the dark. The mixture was measure at 735 nm. The percentage of ABTS scavenging capacity was calculated using the formula:

(Eq. 3)

{ABTS}^{+} scavenging effect (%) = [({Abs}_{control} - {Abs}_{sample}) / {Abs}_{control}] \times 100

For the DPPH assay, 0.2 mM DPPH was dissolved in ethanol. The measurement was followed by the Blois method (Blois, 1958). The extract (750 µL) and 0.2 mM DPPH solution were mixed and reacted for 30 minutes at RT in the dark, and was measured at 525 nm. The percentage of DPPH scavenging capacity was calculated as:

(Eq. 4)

DPPH scavenging effect (%) = [({Abs}_{control} - {Abs}_{sample}) / {Abs}_{control}] \times 100

Statistical analysis

Statistical analysis was conducted using SAS software version 9.2 (SAS Institute, Cary, NC, USA). Data were compared using one-way ANOVA and LSD test. And graphs were made using Sigma Plot (v. 14.5, SYSTAT, Palo Alto, CA, USA).

Results and Discussion

Effect of illite-containing prototypes on soil chemical properties

All prototype of illite-containing fertilizers in AC-NPS significantly increased the pH of soil by 0.4 to 0.9 compared to before the test and without fertilizer (Table 4). In contrast, soil pH in AK-NRS did not show the similar patterns between illite-only and illite-containing prototypes. The electrical conductivity (EC), a soil nutrient index (Mazur et al., 2022), was significantly elevated by an addition of illite-containing prototypes in AC-NPS, whereas the higher EC in AK-NRS was only observed in the prototype-A. Total nitrogen (N) in soil showed a significantly increasing tendency, and this was most remarkable in the prototype-A in both AC-NPS and AK-NRS. On the other hand, soil K was the most abundant in the prototype-B and -C in both soil types, and soil calcium (Ca) was greatly enhanced in AC-NPS. Our result was in line with previous observations (Lee et al., 2012, 2021), which the soil potassium (K) and calcium (Ca) were markedly increased by the application illite-containing materials. Taken together, the relative abundant cations of illite contributed to an enhancement of soil potassium (K) and calcium (Ca), and this suggests that illite-containing prototypes could be used as a nutrient provider for crop growth and development.

Table 4.

Soil chemical properties by application of different illite-containing prototypes. Data indicate mean ± S.D. (n = 3).

Soil^†	Time^‡	Treatment	pH (1:5)	EC (dS m^-1)	T-N (%)	Avail. P₂O₅ (mg kg^-1)	Exch. cations (cmol_c kg^-1)
Soil^†	Time^‡	Treatment	pH (1:5)	EC (dS m^-1)	T-N (%)	Avail. P₂O₅ (mg kg^-1)	K	Ca	Mg
AC- NPS	Before	-	5.1 ± 0.0 c^§	0.2 ± 0.0 f	0.04 ± 0.00 f	4 ± 0 e	0.2 ± 0.0 bc	0.6 ± 0.0 e	0.9 ± 0.0 a
	After	No fert.	5.1 ± 0.1 c	0.2 ± 0.0 e	0.47 ± 0.02 c	4 ± 1 e	0.2 ± 0.0 d	0.8 ± 0.0 d	0.6 ± 0.0 d
		NPK	5.9 ± 0.0 a	0.3 ± 0.0 d	0.42 ± 0.03 de	17 ± 1 c	0.2 ± 0.0 d	1.1 ± 0.0 b	0.7 ± 0.0 c
		Illite	5.5 ± 0.3 b	0.3 ± 0.0 d	0.45 ± 0.02 cd	3 ± 0 e	0.2 ± 0.0 cd	1.1 ± 0.0 b	0.8 ± 0.0 b
		Prototype-A	5.8 ± 0.0 a	0.3 ± 0.0 c	0.54 ± 0.01 a	8 ± 1 d	0.2 ± 0.0 cd	1.0 ± 0.0 c	0.6 ± 0.0 d
		Prototype-B	5.8 ± 0.1 a	0.5 ± 0.0 b	0.50 ± 0.02 b	26 ± 1 a	0.3 ± 0.0 a	1.3 ± 0.0 a	0.8 ± 0.0 b
		Prototype-C	6.0 ± 0.0 a	0.7 ± 0.0 a	0.42 ± 0.03 e	23 ± 0 b	0.3 ± 0.0 ab	1.0 ± 0.0 c	0.8 ± 0.0 d
AK- NRS	Before	-	8.1 ± 0.0 d	2.5 ± 0.1 b	0.31 ± 0.04 f	304 ± 53 c	2.1 ± 0.0 a	21.3 ± 0.2 a	4.6 ± 0.1 a
	After	No fert.	8.3 ± 0.0 b	2.5 ± 0.0 b	3.78 ± 0.08 b	432 ± 9 b	1.4 ± 0.0 c	13.8 ± 0.1 c	3.8 ± 0.0 c
		NPK	8.3 ± 0.0 b	2.1 ± 0.0 c	3.69 ± 0.11 bc	455 ± 17 ab	1.5 ± 0.1 bc	13.3 ± 0.2 d	3.7 ± 0.1 c
		Illite	8.4 ± 0.1 a	1.5 ± 0.0 d	3.44 ± 0.04 e	419 ± 11 b	1.4 ± 0.0 c	12.1 ± 0.1 f	3.3 ± 0.1 e
		Prototype-A	8.1 ± 0.1 cd	2.9 ± 0.1 a	3.91 ± 0.11 a	473 ± 6 a	1.4 ± 0.0 c	14.5 ± 0.1 b	3.9 ± 0.0 b
		Prototype-B	8.2 ± 0.0 b	2.5 ± 0.0 b	3.52 ± 0.06 de	474 ± 4 a	1.4 ± 0.0 bc	12.6 ± 0.2 e	3.5 ± 0.1 d
		Prototype-C	8.2 ± 0.0 bc	2.5 ± 0.0 b	3.59 ± 0.03 cd	487 ± 8 a	1.5 ± 0.1 b	12.6 ± 0.1 e	3.5 ± 0.1 d

^†AC-NPS, acidic nutrient-poor soil; AK-NRS, alkaline nutrient-rich soil.

^‡Time indicate before fertilizing soil (before) and collected soils (after) at the time the plants were sampled 30 days after fertilizer treatment.

^§Different letters indicate statistically significant differences according to LSD test at p ≤ 0.05 (n = 3).

Effect of illite-containing prototypes on lettuce growth

Indeed, the level of mineral nutrients affects plant growth and development. Number of lettuce leaf was significantly much more in AK-NRS compared to AC-NPS, which indicated approximately 2 to 3-fold higher (Table 5). Chemical fertilizer in AC-NPS resulted in distinct greater leaf development, and this contributed to significant increase in leaf fresh weight. In contrast, eventhough much more leaf development compared to AC-NPS, the AK-NRS-grown lettuce did not show significant differences in leaf development and fresh weight among treatments. However, illite-containing prototypes in AC-NPS extremely promoted an increase in leaf length, and it was obvious by prototype-B and -C. Leaf width also showed an increasing tendency by an application of illite-containing prototypes, although there was not significant difference among treatment groups. This result was in line with our previous study with tomato, which indicated that illite-containing fertilizer showed relatively lower growth rate compared to inorganic fertilizer (Lee et al., 2021). From the result, at least, illite-containing prototypes have an effect on the size of an individual leaf rather than number of leaf.

Table 5.

Leaf parameter and growth of lettuce plants fed with different illite-containing prototypes for 30 days. Data indicate mean ± S.D. (n = 3).

Soil^†	Treatment	No. of leaves (per plant)	Leaf length (cm)	Leaf width (cm)	Fresh weight (g plant^-1)
AC-NPS	Control	7.3 ± 1.5 b^‡	10.1 ± 0.5 b	4.6 ± 0.2 b	3.2 ± 1.5 b
	NPK	12.0 ± 0.0 a	15.3 ± 0.5 a	6.3 ± 1.1 a	6.5 ± 0.3 a
	Illite	7.3 ± 1.5 b	7.3 ± 0.8 c	4.5 ± 0.3 b	3.4 ± 0.7 b
	Prototype-A	9.3 ± 0.6 b	11.1 ± 1.2 b	5.0 ± 0.1 b	4.7 ± 0.5 ab
	Prototype-B	7.0 ± 1.0 b	10.8 ± 1.3 b	5.1 ± 0.6 b	4.0 ± 1.3 b
	Prototype-C	8.7 ± 2.5 b	7.1 ± 0.8 c	4.6 ± 0.5 b	4.3 ± 1.5 b
AK-NRS	Control	23.0 ± 1.7 ab	17.6 ± 1.7 bc	8.7 ± 1.1 ns	21.5 ± 3.7 ns
	NPK	23.7 ± 2.9 a	16.1 ± 2.2 c	9.2 ± 1.4	19.3 ± 4.5
	Illite	23.0 ± 2.6 ab	15.5 ± 2.8 c	9.0 ± 1.5	21.5 ± 1.4
	Prototype-A	21.0 ± 2.0 ab	17.1 ± 1.1 bc	10.5 ± 0.5	17.8 ± 4.4
	Prototype-B	19.3 ± 2.1 b	22.0 ± 2.4 a	10.2 ± 2.1	16.1 ± 3.9
	Prototype-C	20.7 ± 1.5 ab	20.5 ± 3.4 ab	11.1 ± 1.7	18.2 ± 2.3

^†AC-NPS, acidic nutrient-poor soil; AK-NRS, alkaline nutrient-rich soil.

^‡Different letters indicate statistically significant differences according to LSD test at p ≤ 0.05 (n = 3).

Macro nutrients including N was also measured at 30 DAT from the shoot (leaves) of lettuce grown under different soil and fertilization types (Table 6). Except for total carbon (T-C), all measured nutrients were significantly higher in AC-NPS-grown lettuce. In both soil types, the prototype-B application resulted in the highest N concentration, 4.76 (AC-NPS) and 6.10 (AK-NRS), respectively. In particular, illite-containing prototypes greatly contributed to the accumulation of leaf N in AC-NPS, and, promoted the significant increase in K, Ca and Mg. The prototype-B also showed the similar effect in AK-NRS, which enhanced the level of T-N, Ca and Mg. This is the similar to the result that illite treatment increased mineral content of bean sprouts (Ha et al., 2022). The T-C was significantly higher in the AC-NPS-grown lettuce compared to those in AK-NRS, and it is closely related to N content. The absorbed N is preferentially used for the production of nitrogen-containing organic compounds such as amino acids and chlorophyll (Ohyama, 2010). The previous studies well documented that the N supply led to an abundant N content in leaves, which is mainly located in the photosynthetic protein complex, thereby enhancing photosynthesis and plant growth (Vos et al., 2005; Liu et al., 2019; Yue et al., 2021). Therefore, our observation suggests that the prototype-B could be an useful provider to promote nutrient uptake by lettuce plant, and an availability of nutrients is not affected by soil chemical properties.

Table 6.

Macro nutrients of lettuce (Lactuca sativa L.) plants applied with different types of illite-containing agricultural prototypes (n = 3).

Soil^†	Treatment	T-C (%)	T-N (%)	P₂O₅ (%)	K₂O (%)	CaO (%)	MgO (%)
AC- NPS	Control	40.5 ± 0.1 a^‡	1.52 ± 0.03 d	0.16 ± 0.02 cd	4.12 ± 0.15 c	0.34 ± 0.01 c	0.24 ± 0.01 d
	NPK	40.1 ± 0.1 b	2.31 ± 0.03 c	0.17 ± 0.01 c	4.42 ± 0.35 c	0.49 ± 0.04 ab	0.28 ± 0.02 b
	Illite	39.7 ± 0.2 c	2.16 ± 0.07 c	0.17 ± 0.01 c	4.54 ± 0.18 c	0.51 ± 0.02 a	0.29 ± 0.01 ab
	Prototype-A	40.6 ± 0.2 a	2.08 ± 0.07 c	0.15 ± 0.01 d	4.23 ± 0.33 c	0.46 ± 0.01 b	0.27 ± 0.02 bc
	Prototype-B	39.9 ± 0.2 bc	4.76 ± 0.43 a	0.27 ± 0.01 a	5.75 ± 0.22 a	0.51 ± 0.02 a	0.32 ± 0.02 a
	Prototype-C	40.4 ± 0.2 a	3.37 ± 0.14 b	0.19 ± 0.01 b	5.11 ± 0.28 b	0.36 ± 0.02 c	0.25 ± 0.01 cd
AK- NRS	Control	36.0 ± 0.1 b	5.84 ± 0.01 bc	0.65 ± 0.01 ns	10.06 ± 0.48 a	1.83 ± 0.07 b	0.75 ± 0.04 ab
	NPK	36.0 ± 0.2 b	5.77 ± 0.05 c	0.64 ± 0.02	9.35 ± 0.23 abc	1.87 ± 0.08 b	0.68 ± 0.02 ab
	Illite	37.0 ± 0.1 a	5.35 ± 0.08 d	0.65 ± 0.02	9.21 ± 0.59 bc	1.55 ± 0.09 c	0.56 ± 0.02 c
	Prototype-A	35.9 ± 0.2 b	6.06 ± 0.14 a	0.64 ± 0.01	8.68 ± 0.16 c	1.92 ± 0.08 ab	0.64 ± 0.03 bc
	Prototype-B	34.8 ± 0.1 c	6.10 ± 0.04 a	0.65 ± 0.01	9.71 ± 0.20 ab	2.13 ± 0.16 a	0.81 ± 0.06 a
	Prototype-C	35.0 ± 0.2 c	5.92 ± 0.08 b	0.68 ± 0.01	9.29 ± 0.56 abc	2.09 ± 0.18 a	0.74 ± 0.04 a

^†AC-NPS, acidic nutrient-poor soil; AK-NRS, alkaline nutrient-rich soil.

^‡Different letters indicate statistically significant differences according to LSD at p ≤ 0.05 (n = 3).

Effect of illite-containing prototypes on chlorophyll and antioxidant capacity of lettuce

The content of chlorophyll a and b was obviously higher in lettuce treated with the prototype-B and -C in AK-NRS, even although, in AC-NPS, chemical fertilization (NPK) showed the greatest level (Fig. 2). By contrast, chlorophyll a/b ratio did not differ from the treatments, both soil and fertilization. Compared to T-N content of lettuce leaves, there was no or little relationship between N and chlorophyll contents. It seems that nitrogen is preferentially metabolized into chlorophyll biosynthesis pathway to promote photosynthesis, as observed in previous study which indicated three times greater in tomato plant by an application illite-containing fertilizer (Lee et al., 2021). Based on our result, the prototype-B and -C clearly represent an enhancing effect of chlorophyll production in the AC-NPS-grown lettuce plant.

https://static.apub.kr/journalsite/sites/ksssf/2023-056-01/N0230560103/images/ksssf_2023_561_27_F2.jpg

Fig. 2.

Chlorophyll contents in lettuce (Lactuca sativa L.) plants applied with different types of illite-containing prototypes (n = 3). AC-NPS, acidic nutrient-poor soil; AK-NRS, alkaline nutrient-rich soil.

The antioxidant activity such as total polyphenols, total flavonoids, ABTS⁺ and DPPH were observed from the lettuce leaves treated with different soil and fertilization types (Fig. 3). All types of antioxidative indicators significantly greater in the AC-NPS-grown lettuce leaves irregardless of the types of fertilization including illite-containing prototypes. Additionally, the antioxidant activity resulted in an inverse proportion with fertilization levels. In particular, in AC-NPS, illite was significantly increased content of total polyphenols (19.5 mg g^-1), flavonoids (3.8 mg g^-1), and ABTS scavenging capacity (37.2%). This is the similar pattern to previous observations with tomato and soybean (Lee et al., 2021; Ha et al., 2022). Therefore, antioxidant activity is greatly depended on the level of available nutrients in soil due to the relatively higher nutrient of illite-containing prototypes.

https://static.apub.kr/journalsite/sites/ksssf/2023-056-01/N0230560103/images/ksssf_2023_561_27_F3.jpg

Fig. 3.

Total nitrogen, total polyphenol, flavonoids, ABTS⁺ and DPPH radical scavenging activities in lettuce plants applied with different types of illite-containing prototypes (n = 3). AC-NPS, acidic nutrient-poor soil; AK-NRS, alkaline nutrient-rich soil.

Conclusions

In conclusion, this work tried to examine whether various illite-containing prototypes as an alternative chemical fertilizers are the effects on lettuce growth, nutrient uptake and antioxidant activity. Of those, prototype-B and -C elevated EC value in the AC-NPS. Illite-containing prototypes showed an enlargement of individual leaf of AK-NRS-grown lettuce plant. Additionally, prototype-B and -C resulted in an enrichment of macro nutrients (N, K and Ca) and antioxidant activity in the AC-NPS. Taken together, illite-containing prototypes (B and C) could be used as an alternative or supplement of chemical fertilizer for suitable lettuce grown in the AC-NPS. On the basis of positive effects of illite-containing prototype fertilizer, further study is suggested to be extend to various vegetable crops.

Acknowledgements

This research was performed with the financial support of Korea Institute of Ceramic Engineering & Technology (2020).

References

Ahanger, M.A. and R.M. Agarwal. 2017. Potassium up-regulates antioxidant metabolism and alleviates growth inhibition under water and osmotic stress in wheat (Triticum aestivum L). Protoplasma 254(4):1471-1486. 10.1007/s00709-016-1037-027783181

Ahanger, M.A., N.S. Tomar, M. Tittal, S. Argal, and R.M. Agarwal. 2017. Plant growth under water/salt stress: ROS production; antioxidants and significance of added potassium under such conditions. Physiol. Mol. Biol. Plants 23(4):731-744. 10.1007/s12298-017-0462-729158624PMC5671444

Barre, P., B. Velde, and L. Abbadie. 2007. Dynamic role of “illite-like” clay minerals in temperate soils: Facts and hypotheses. Biogeochemistry 82(1):77-88. 10.1007/s10533-006-9054-2

Blois, M.S. 1958. Antioxidant determinations by the use of a stable free radical. Nature 181(4617):1199-1200. 10.1038/1811199a0

Cho, H.G., O.H. Park, D.H. Moon, J.Y. Do, and S.O. Kim. 2007. Phosphate adsorption of Youngdong illite, Korea. J. Mineral. Soc. Korea 20(4):327-337.

Choi, Y.S., Y.J. Kang, D.H. Kim, C.K. Lee, and S.I. Yun. 2021. Effects of chelating agent and micronutrient application on nutrient content and growth of lettuce in soils with different salinity and acidity. Korean J. Soil Sci. Fert. 54:578-587. 10.7745/KJSSF.2021.54.4.578

Folin, O. and W. Denis. 1912. On phosphotungstic-phosphomolybdic compounds as color reagents. J. Biol. Chem. 12:239-243. 10.1016/S0021-9258(18)88697-5

Ha, M.C., D.Y. Im, H.S. Park, S.K. Dhungana, I.D. Kim, and D.H. Shin. 2022. Seed treatment with illite enhanced yield and nutritional value of soybean sprouts. Molecules 27(4):1152. 10.3390/molecules2704115235208942PMC8875372

Hashemi, S.S. and H. Abbaslou. 2016. Potassium reserves in soils with arid and semi-arid climate in southern Iran: A perspective based on potassium fixation. Iran Agric. Res. 35(2):88-95.

Hwang, J., S. Choung, C.S. Park, J.H. Han, and S. Jeon. 2016. Application of Yeongdong illite to remove radiocesium for severe nuclear accidents. J. Mineral. Soc. Korea 29(4):229-238. 10.9727/jmsk.2016.29.4.229

Isherwood, K.F. 2000. Mineral fertilizer use and the environment. International Fertilizer Industry Association, United Nations Environment Programme, Paris, France.

Kumari, N. and C. Mohan. 2021. Basics of clay minerals and their characteristic properties. p. 1-29. In G.M. Do Nascimento (ed.) Clay and Clay Minerals. InTechOpen, London, UK. 10.5772/intechopen.97672

Lee, S.E., D.H. Kim, H.K. Hong, S.M. Kwon, M.S. Lee, S.H. Woo, and K.Y. Chung. 2012. Effect of different levels of applications of illite on the growth of red pepper in soil. Korean J. Soil Sci. Fert. 45(3):339-343. 10.7745/KJSSF.2012.45.3.339

Lee, Y.J., J.K. Sung, S.B. Lee, J.E. Lim, Y.S. Sung, D.B. Lee, and S.Y. Hong. 2017. Plant analysis methods for evaluating mineral nutrient. Korean J. Soil Sci. Fert. 50(2):93-99. 10.7745/KJSSF.2017.50.2.093

Lee, Y.R., H.S. Lee, G.E. Kim, Y.T. Shin, J.Y. Joo, J.J. Lee, and J. Sung. 2021. Effects of illite-containing fertilizer prototype on soil chemical property and tomato growth. Korean J. Soil Sci. Fert. 54:338-346. 10.7745/KJSSF.2021.54.3.338

Liu, J.Z., J.C. Yuan, K. Zhou, Y. Liang, X.G. Yan, H.X. Zhang, J. Ren, and H.J. Cai. 2019. Effect of different nitrogen fertilizer application rates on photosynthetic characteristic and yield. J. Maize Sci. 27:151-157.

Mazur, P., D. Gozdowski, and E. Wójcik-Gront. 2022. Soil electrical conductivity and satellite-derived vegetation indices for evaluation of phosphorus, potassium and magnesium content, pH, and delineation of within-field management zones. Agriculture 12(6):883. 10.3390/agriculture12060883

Moreno, M.I.N., M.I. Isla, A.R. Sampietro, and M.A. Vattuone. 2000. Comparison of the free radical-scavenging activity of propolis from several regions of Argentina. J. Ethnopharmacol. 71(1-2):109-114. 10.1016/S0378-8741(99)00189-010904153

NIAS. 2000. Soil and plants analysis method. National Institute of Agricultural Sciences, RDA, Jeonju, Korea.

NIAS. 2017. Fertilizer recommendation for crop production (3rd ed.). National Institute of Agricultural Sciences, RDA, Jeonju, Korea.

Nicolle, C., A. Carnat, D. Farisse, J.L. Lamaison, E. Rock, H. Michel, P. Amouroux, and C. Remesy. 2004. Characterisation and variation of antioxidant micronutrients in lettuce (Lactuca sativa folium). J. Sci. Food Agric. 84(15):2061-2069. 10.1002/jsfa.1916

Ohyama, T. 2010. Nitrogen as a major essential element of plants. p. 1-18. In T. Ohyama and K. Sueyoshi (ed.) Nitrogen assimilation in plants. Research Signpost, Kerala, India.

Paola, A., B. Pierre, C. Vincenza, D.M. Vincenzo, and V. Bruce. 2016. Short term clay mineral release and re-capture of potassium in a Zea mays field experiment. Geoderma 264:54-60. 10.1016/j.geoderma.2015.10.005

Porra, R.J. 2002. The chequered history of the development and use of simultaneous equations for the accurate determination of chlorophylls a and b. Photosynth. Res. 73(1):149-156.

Re, R., N. Pellegrini, A. Proteggente, A. Pannala, M. Yang, and C. Rice-Evans. 1999. Antioxidant activity applying an improved ABTS radical cation decolorization assay. Free Radical Biol. Med. 26(9-10):1231-1237. 10.1016/S0891-5849(98)00315-310381194

Vos, J., P.E.L. van der Putten, and C.J. Birch. 2005. Effect of nitrogen supply on leaf appearance, leaf growth, leaf nitrogen economy and photosynthetic capacity in maize (Zea mays L.). Field Crops Res. 93:64-73. 10.1016/j.fcr.2004.09.013

Weaver, C.E. 1965. Potassium content of illite. Science 147(3658):603-605. 10.1126/science.147.3658.60317783264

Yue, K., L. Li, J. Xie, S.K. Fudjoe, R. Zhang, Z. Luo, and S. Anwar. 2021. Nitrogen supply affects grain yield by regulating antioxidant enzyme activity and photosynthetic capacity of maize plant in the loess plateau. Agronomy 11:1094. 10.3390/agronomy11061094

Korean Journal of Soil Science and Fertilizer ISSN:0367-6315(Print) 2288-2162(Online) 한국토양비료학회 학회지

Preview

Effects of Illite-Containing Fertilizer Prototypes on Nutrients Uptake and Antioxidant of Lettuce (Lactuca sativa L.)

ABSTRACT

Effect of illite-containing prototypes on total nitrogen and antioxidant ability of lettuce plant.

MAIN

Table 1.

Physicochemical properties of experimental soils.

Table 2.

Physiocochemical composition of illite prototypes used in this study.

Table 3.

Composition of various illite-containing prototypes.

Fig. 1.

Different types of illite-containing prototypes for agricultural use. The detailed composition of each prototypes was described in Table 3.

(Eq. 1)

(Eq. 2)

(Eq. 3)

(Eq. 4)

Table 4.

Soil chemical properties by application of different illite-containing prototypes. Data indicate mean ± S.D. (n = 3).

Table 5.

Leaf parameter and growth of lettuce plants fed with different illite-containing prototypes for 30 days. Data indicate mean ± S.D. (n = 3).

Table 6.

Macro nutrients of lettuce (Lactuca sativa L.) plants applied with different types of illite-containing agricultural prototypes (n = 3).

Fig. 2.

Chlorophyll contents in lettuce (Lactuca sativa L.) plants applied with different types of illite-containing prototypes (n = 3). AC-NPS, acidic nutrient-poor soil; AK-NRS, alkaline nutrient-rich soil.

Fig. 3.

Total nitrogen, total polyphenol, flavonoids, ABTS+ and DPPH radical scavenging activities in lettuce plants applied with different types of illite-containing prototypes (n = 3). AC-NPS, acidic nutrient-poor soil; AK-NRS, alkaline nutrient-rich soil.

Acknowledgements

References

Total nitrogen, total polyphenol, flavonoids, ABTS⁺ and DPPH radical scavenging activities in lettuce plants applied with different types of illite-containing prototypes (n = 3). AC-NPS, acidic nutrient-poor soil; AK-NRS, alkaline nutrient-rich soil.