Skip to content
Frontiers
Search

Original Research

Frontiers in Sustainable Food Systems ·

Volume 10 - 2026 | https://doi.org/10.3389/fsufs.2026.1948663

Agronomic performance and soil chemical properties following the application of pelletized compost and vermicompost derived from vineyard pruning residues and sewage sludge in lettuce production

  • Maria C. Morais1*corresponding author
  • Elisabete Nascimento-Gonçalves1
  • Lia-Tânia Dinis1
  • Sandra Pereira1
  • Zélia Branco1
  • Henda Lopes1
  • Tiago Azevedo1
  • Catarina Medeiros1
  • Ana M. Coimbra1
  • João Claro2
  • Guilhermina Marques1,3
  • João R. Sousa1
  • Paula A. Oliveira1
  • Marta Roboredo1
  1. 1Centre for the Research and Technology of Agroenvironmental and Biological Sciences (CITAB), Inov4Agro, Universidade de Trás-os-Montes e Alto Douro, Vila Real, Portugal
  2. 2CQ-VR Centre of Chemistry-Vila Real, Universidade de Trás-os-Montes e Alto Douro, Vila Real, Portugal
  3. 3Department of Agronomy, School of Agrarian and Veterinary Sciences, Universidade de Trás-os-Montes e Alto Douro, Vila Real, Portugal
Article metrics0 viewsView details
PDFCiteMetrics

Abstract

Compost and vermicompost are recognized as effective organic amendments for supporting plant growth, promoting nutrient recycling and enhancing soil quality within circular economy strategies. In this context, the present study evaluated the short-term performance of pelletized compost (CC) and vermicompost (VC) produced from vineyard prunings and sewage sludge on lettuce (Lactuca sativa L.) growth, leaf biochemical traits, mineral composition, and soil chemical properties. The performance of both organic products was compared with a commercial organomineral fertilizer (CF) and an unfertilized control (CT). A completely randomized greenhouse pot experiment was conducted for 55 days comprising four treatments with eight replicates each.. Data were analyzed by one-way ANOVA followed by Tukey´s HSD test at p < 0.05, with non-parametric analysis used when ANOVA assumptions were not met. At the end of the experiment, organic amendments performed comparably to the commercial fertilizer CF for most morphological parameters, despite differences in absolute nutrient inputs among treatments, although shoot fresh weight remained higher under CF. Leaf biochemical responses varied among treatments: CC and CF exhibited high chlorophyll and carotenoid contents, whereas VC and CT showed lower pigment concentrations. Total soluble sugars were highest in CT and lowest in CF, while total protein and phenolic contents were not significantly affected by treatment. Leaf macronutrient concentrations under CC and VC were generally comparable to CF, while for micronutrients Fe and Mn concentrations were higher in CF. Final soil analyses showed higher organic matter, extractable P and K, and cation exchange capacity under organic fertilization, whereas CF showed the lowest soil pH. Trace metal concentration remained low in all treatments. These findings support the potential use of compost and vermicompost derived from vineyard pruning residues and sewage sludge as recycled organic amendments for horticultural production. However, further research is recommended to validate these results under long-term field conditions and diverse soil types.

Keywords

1 Introduction

Efficient nutrient management is essential for maintaining crop productivity while reducing the environmental impacts associated with fertilizer use. The intensive and often excessive use of synthetic fertilizers has generated increasing environmental concerns, including greenhouse gas emissions (Song et al., 2022; Xu et al., 2023), nutrient leaching, soil acidification (Krasilnikov et al., 2022), biodiversity loss (Gaga et al., 2022), and potential risks to human health (Muscolo et al., 2022; Adebanjo-Aina and Oludoye, 2025). These impacts are particularly relevant in short-cycle horticultural crops, where high nutrient inputs are frequently applied to maximize productivity. In addition to environmental pressures, inefficient fertilization practices contribute to rising production costs and reduced economic efficiency (Jatav and Rajput, 2025). At the same time, agricultural and urban activities generate large volumes of organic residues whose inadequate management represents a loss of valuable resources and may further contribute to environmental degradation (Xu et al., 2024).

Within this context, circular economy strategies have gained increasing relevance by promoting the recycling of organic residues into value-added products such as compost and vermicompost. Compost is produced through the aerobic decomposition of organic matter (Cozzolino et al., 2023), whereas vermicompost results from the combined activity of earthworms and microorganisms (Rehman et al., 2023), often yielding materials with enhanced nutrient availability and biological activity (Lin et al., 2019). Both products have been shown to sustain or even enhance crop growth and yield while improving soil health and reduce dependence on synthetic fertilizers (Libutti et al., 2020; Lara-Capistrán et al., 2020; Diatta et al., 2023; Pacheco et al., 2023; Almaramah et al., 2024; Dayan and Bayram, 2025). In addition, they may improve soil structure (Castellini et al., 2025), increase organic carbon stocks (Ngo et al., 2014), enhance nutrient availability (Goswami et al., 2017; Zapałowska et al., 2025), stimulate biological activity (Zapałowska et al., 2025), and mitigate biotic and abiotic stresses (Yatoo et al., 2021; Liu et al., 2024; Suhani et al., 2025). Nevertheless, the performance of compost and vermicompost depends strongly on crop species, amendment composition, application rate and management practices (Liu et al., 2024). Unlike synthetic fertilizers, compost and vermicompost contain nutrients largely in organic forms, whose availability depends on mineralization dynamics (Garcia et al., 2026). Therefore, their agronomic value should be assessed not only through short-term crop growth, but also through their effects on soil chemical fertility.

Lettuce (Lactuca sativa L.) is one of the most widely cultivated leafy vegetables worldwide and represents a key crop in intensive horticultural production systems (Alromian, 2020; Muscolo et al., 2022). Due to its rapid growth and high nitrogen demand, lettuce production typically relies on substantial fertilizer inputs (Sylvestre et al., 2019; Kavvadias et al., 2023), which may increase the risk of nitrate accumulation in leaves and nitrogen leaching into the environment (Sylvestre et al., 2019; González-Miranda et al., 2021). Several studies have reported the beneficial effects of organic amendments on lettuce growth and yield (Hernández et al., 2016; Marutani and Clemente, 2021; Olaniyan et al., 2026), as well as on other vegetable crops such as sweet pepper (Lara-Capistrán et al., 2020), bell pepper (Sanchez et al., 2024), carrot (Aina et al., 2025), red radish (Almaramah et al., 2024), cowpea (Badar et al., 2015), tomato (Cozzolino et al., 2023), and broccoli (Dayan and Bayram, 2025). Despite this, most studies on lettuce have focused primarily on morphological traits or productivity (Alromian et al., 2020; Theourn et al., 2021; Kavvadias et al., 2023). In contrast, integrated assessments combining plant growth, nutritional status, biochemical responses, and soil chemical properties under organic fertilization remain limited.

To address this gap, the present study evaluated the short-term agronomic performance and soil chemical responses to pelletized compost and vermicompost produced from vineyard pruning residues and sewage sludge in a lettuce pot experiment. These two organic waste streams possess complementary characteristics for biological valorization: sewage sludge is rich in organic matter and nutrients (Lopes et al., 2026), while pruning residues is a source of carbon, lignin, and cellulose (Jesus et al., 2022). Pelletization was selected as a formulation strategy becau se it can facilitate the handling, transport, storage, and field application of organic amendments, thereby increasing their practical applicability and commercial potential. The novelty of this study lies in the application of pelletized compost and vermicompost produced from a combination of vineyard pruning residues and sewage sludge, as soil amendments for lettuce production, alongside with an evaluation of plant performance, nutritional status, biochemical responses, and soil chemical properties. This approach contributes to waste valorization and circular economy strategies for intensive horticultural systems.

2 Material and methods

2.1 Soil collection and physicochemical characterization

Topsoil (0–20 cm) was collected from an agricultural field located in Mêda, Portugal (40°56'27.8"N,7°16'10.4"W; 755 m above sea level). The soil in this location is classified as a dystric cambisol derived from granite (IUSS Working Group WRB, 2022). The collected soil was air-dried, homogenized, and sieved (< 2 mm) to remove stones and coarse debris. A composite sample was analyzed for physicochemical properties at the Soil and Plant Analysis Laboratory of UTAD using standard procedures.

Soil pH (H2O) and electrical conductivity (EC) were determined in a 1:5 (w/v) soil to deionized water suspension following the ISO 10390 (2021) and ISO 11265 (2025), respectively. Total N was determined by the Kjeldahl method (Kjeldahl, 1883). Extractable P and K were determined using the Egner–Riehm extraction method (Egnér et al., 1960). Micronutrients (Cu, Zn, Fe, and Mn) were extracted in a 1:10 soil-to-AAAc-EDTA solution at pH 4.65 (Lakanen and Erviö, 1971) and quantified by atomic absorption spectroscopy, while extractable B was determined in hot water (1:2 soil-to-water ratio) and analyzed by ICP-OES (FAO, 2024). Effective cation exchange capacity, calculated as the sum of exchangeable Ca, Mg, K, and Na plus exchangeable acidity, was extracted with barium chloride and analyzed by ICP-OES following ISO 11260 (2018). Soils’ particle-size distribution was determined using a Skalar Robotic Analyzer SP2000 after removal organic matter (OM) with H2O2 and carbonates with HCl, with sodium pyrophosphate added during analysis. Trace element (Cu, Zn, Pb, Cd, Cr, Ni, and Hg) were determined according to ISO 54321 (2020).

Overall, the soil used in the experiment has a loamy sandy texture and is characterized by low organic matter content and low cation exchange capacity (Table 1). The soil pH value (6.2) is within the optimal range (5.8-6.6) recommended for lettuce cultivation (Thamburaj and Singh, 2001).

Table 1. Physicochemical characteristics of the soil used in the experiment.

Soil characteristicsValue
pH (H2O)6.2
Electrical conductivity (dS m−1)0.049
Organic matter (%)2.09
CEC (cmolc kg−1)4.62
Exchangeable Ca (cmolc kg−1)3.09
Exchangeable Mg (cmolc kg−1)0.87
Exchangeable K (cmolc kg−1)0.19
Exchangeable Na (cmolc kg−1)0.05
Exchangeable Al (cmolc kg−1)0.45
Sand (%)86.7
Silt (%)6.0
Clay (%)7.3
Total N (g N kg−1)1.22
Extractable P (mg P2O5 kg−1)21
Extractable K (mg K2O kg−1)97
Extractable micronutrients (mg kg−1)
B0.11
Cu2.08
Zn1.79
Fe78.3
Mn29.5
Trace elements
Cu (mg Cu kg−1)11.6
Zn (mg Zn kg−1)30
Pb (mg Pb kg−1)4.4
Cd (mg Cd kg−1)0.28
Cr (mg Cr kg−1)8.8
Ni (mg Ni kg−1)4.5
Hg (μg Hg kg−1)7

2.2 Compost and vermicompost production characterization

Compost and vermicompost were produced from a mixture of vineyard pruning residues and sewage sludge, using the solid fraction of cattle slurry as inoculum. Composting was carried out in insulated reactors under controlled aeration, with 10 events over 140-days. After this period, part of the compost was transferred to 56-L wooden boxes containing Eisenia fetida earthworms (25 g per kg compost) for vermicomposting (100 days), while the remaining compost continued maturation during the same time period.

Both compost and vermicompost were dried, sieved (< 2 mm), and evaluated for maturity and stability using germination and respiration techniques, respectively. Phytotoxicity was evaluated through the seed germination index (GI) using Lepidium sativum L. seeds, following the method described by Zucconi et al. (1981). Mean GI values were above the 80% threshold commonly associated with mature material and absence of phytotoxicity (Kebibeche et al., 2019), with compost registering 90.2 ± 12.8% (ranging from 73.7% to 106.3%, n = 5) and vermicompost 81.1 ± 9.3% (ranging from 69.4% to 92.2%, n = 5).

Basal respiration, indicative of microbial activity, was estimated from C-CO2 emissions, according to Anderson (1982) and was 1.95 ± 0.17 mg CO2 g−1 OM d−1 for compost and 2.23 ± 0.27 mg CO2 g−1 OM d−1 for vermicompost, indicating biologically stable material. Microbiological safety was evaluated by determining total faecal coliforms (Escherichia coli) and Salmonella spp. (Soares et al., 2019). Both compost and vermicompost presented E. coli counts below 103 CFU g−1 (fresh weight), and Salmonella spp. were absent, confirming their microbiological safety in compliance with the limits established by Portuguese legislation (Portaria no. 185/2022, 21st of July).

The stabilized compost and vermicompost were pelletized with clay, cork powder and water. Their chemical properties were determined at the Soil and Plant Analysis Laboratory of UTAD using the analytical procedures described in the previous section. The main characteristics of pelletized materials are presented in Table 2.

Table 2. Chemical characteristics of the pelletized compost and vermicompost used in the experiment.

Chemical characteristicsCompostVermicompost
pH (H2O)5.85.8
Electrical conductivity (dS m−1)3.854.69
Organic matter (g kg−1 DW)826799
NH4+-N (mg N kg−1 FW)166127
NO3−-N (mg N kg−1 FW)16621520
C/N17.117.8
Moisture (%)15.312.3
MacronutrientsN (g N kg−1 DW)28.026.1
P (g P kg−1 DW)7.517.58
K (g K kg−1 DW)13.514.1
Ca (g Ca kg−1 DW)21.023.6
Mg (g Mg kg−1 DW)7.988.67
S (g S kg−1 DW)8.209.21
MicronutrientsB (mg B kg−1 DW)14.915.9
Fe (mg Fe kg−1 DW)65087594
Cu (mg Cu kg−1 DW)101103
Zn (mg Zn kg−1 DW)306323
Mn (mg Mn kg−1 DW)217234
Trace elementsNi (mg Ni kg−1 DW)4.335.04
Cd (mg Cd kg−1 DW)0.2760.261
Pb (mg Pb kg−1 DW)10.012.0
Cr (mg Cr kg−1 DW)6.648.76
Hg (μg Hg kg−1 DW)43.764.0

DW, dry weight; FW, fresh weight.

The chemical characterization indicated that compost and vermicompost exhibited comparable and agronomically favorable properties, with differences mainly reflecting the effects of earthworm-mediated organic matter oxidation. Vermicompost showed slightly lower organic matter and total N contents but maintained a similar C/N ratio, lower than 20, indicating adequate maturity (Bhat et al., 2017) and stability (Senesi, 1989). The higher electrical conductivity and increased concentrations of most macro- and micronutrients and trace elements in the vermicompost likely reflect enhanced mineralization, organic matter decomposition, and mass reduction during vermicomposting (Mupambwa et al., 2026), while reduced ammonium and nitrate levels suggest progressive N stabilization likely associated with microbial assimilation and transformation processes that promote the incorporation of inorganic N into more stable organic forms (Atiyeh et al., 2000). Trace element concentrations were low in both materials. According to Portuguese legislation governing fertilizing products (Portaria no. 185/2022, 21st of July), both products fall within group 5 (organic amendments) and class II regarding maximum admissible trace element concentrations, making them suitable for agricultural use. In both compost and vermicompost, Zn was the most limiting trace element for defining the maximum application rate to soil.

2.3 Experimental design and morphological measurements

A completely randomized design was conducted under greenhouse conditions with natural light at UTAD, Vila Real, Portugal (41°17′14.8″N 7°44′14.8″W, 500 m above sea level). The experiment consisted of four treatments: commercial fertilization (CF), compost (CC), vermicompost (VC), and a control with no fertilization (CT). For the CF treatment, a commercial granulated organomineral fertilizer (Fertigranu Horta 6-4-8, Nutrofertil, Viseu, Portugal), composed of 77% materials of animal origin and 23% mineral fraction, was applied at 1.5 g per pot (2 kg of soil, DW). According to the manufacturer, the fertilizer contains 48% organic matter, 6% total N (1.1% organic N), 4% P2O5, 8% K2O, 8.6% Ca, 0.3% MgO, and 0.002% B, and is formulated to provide prolonged nutrient release. Compost and vermicompost were applied at 20 g fresh weight per pot. This application rate was established according to Portuguese legislation for fertilizing products (Portaria no. 185/2022, 21st of July), considering the trace element concentrations of both organic amendments. Zinc was the limiting trace element for compost and vermicompost, with total concentrations of 306 and 323 mg kg−1 DW, respectively. These concentrations exceed the limit for Class I materials (200 mg kg−1 DW) but remain below that established for Class II (500 mg kg−1 DW), for which the maximum annual application rate is 25 t FW ha−1. Assuming a soil mass of 2 × 106 kg soil ha−1, the application of 20 g FW to 2 kg of soil corresponds to 20 t FW ha−1, which remains below the maximum permitted application rate. Given the measured moisture contents of compost (15.3%) and vermicompost (12.3%), the corresponding Zn inputs were calculated as 5.18 and 5.67 kg ha−1, respectively, both below the maximum allowable Zn input of 7.5 kg ha−1 year−1. Based on the application rates and nutrient composition of compost and vermicompost, the total nutrient inputs were 90.0, 26.2, and 99.6 mg pot−1 of N, P, and K, respectively, for CF; 474.3, 127.2, and 228.7 mg pot−1 for CC; and 457.8, 133.0, and 247.3 mg pot−1 for VC. Thus, treatments were not established on an equal-nutrient basis; CC and VC were applied at the same fresh-mass rate, which was constrained by regulatory limits, whereas CF was applied at its selected commercial rate. Therefore, the application rate of the organic amendments was defined to comply with legal limits for trace element inputs to soil rather than being adjusted to match the nutrient composition of the commercial fertilizer.

Uniform lettuce seedlings (Lactuca sativa L.) were purchased from a local commercial nursery (Vila Real, Portugal). At transplanting, seedlings were approximately two months old and had a mean fresh weight of 2.77 ± 0.25 g. They were transplanted into 2 L pots filled with air-dried soil. Organic, supplied as dried pellets, and commercial fertilizer were incorporated into the soil prior to transplanting. Eight replicates were considered for each treatment. Pots were watered daily with tap water, randomly arranged, and rotated weekly to minimize positional effects. The experiment was carried out from the 10th of April until the 5th of June 2025. Throughout the experiment, plants were regularly inspected for visual symptoms of nutrient deficiencies, although no quantitative deficiency assessment was performed.

At the end of the experiment, lettuce plants were carefully removed from the soil and the following morphological parameters were determined: fresh weight, stem diameter, height, number of leaves, plant width, leaf area, root length and root fresh weight. After measurement, shoots were separated from roots. Shoot samples were divided into two subsamples: one was immediately frozen in liquid nitrogen and stored at −80 °C until biochemical analyses, while the other was oven-dried at 60 °C to constant weight, for dry biomass determination and mineral analysis. Roots were also oven-dried at 60 °C to constant weight for dry weight determination.

2.4 Leaf biochemical parameters

For biochemical analyses, leaf material from the eight plants of each treatment was combined in non-overlapping pairs, due to the limited biomass available per plant, to obtain four independent composite samples.

Photosynthetic pigments (chlorophyll a, chlorophyll b, total chlorophyll, and total carotenoids) were extracted using 80% (v/v) cold acetone and quantified spectrophotometrically following the methods of Sestak et al. (1971) and Lichtenthaler (1987). Pigment concentrations were expressed in mg g−1 fresh weight (FW).

Total phenols compounds were determined using the Folin-Ciocalteu method (Singleton and Rossi, 1965) with absorbance measured at 725 nm. Results were expressed as mg gallic acid equivalents per gram of extract (mg GAE g−1 FW).

Total soluble sugars were extracted by heating the samples in 80% (v/v) ethanol at 80 °C for 1 h. Quantification was performed using the anthrone method according to Irigoyen et al. (1992), with glucose as the calibration standard. Results were expressed as mg g−1 FW.

Total soluble protein was extracted from 10 mg of fresh sample using phosphate buffer (pH 7.5) containing ethylenediaminetetraacetic acid (EDTA). After centrifugation at 4 °C for 30 min, the supernatant was collected and protein concentration was determined according to Bradford (1976), using Coomassie Brilliant Blue reagent. Absorbance was measured spectrophotometrically, and protein concentration was calculated using bovine serum albumin standard curve. Results were expressed as mg g−1 FW.

2.5 Leaf nutrient content

Dried leaf material from each treatment was combined in non-overlapping pairs, ground and homogenized to obtain four independent composite samples. For the determination of P, K, Ca, Mg, S, B, Fe, Cu, Zn, and Mn, composite samples were subjected to microwave-assisted acid digestion using a HNO3 and H2O2 mixture, and element concentrations were quantified by inductively coupled plasma optical emission spectrometry (ICP-OES). Nitrogen content was determined separately by the Kjeldahl method (Kjeldahl, 1883). All analyses were performed at the Soil and Plant Analysis Laboratory of UTAD.

2.6 Soil analysis

At the end of the experiment, soil from the eight pots of each treatment was pooled, homogenized, and air-dried. Three analytical subsamples were taken from each pooled treatment sample and analyzed at the Soil and Plant Analysis Laboratory of UTAD for chemical properties, following the procedures described in Section 2.1.

2.7 Statistical analysis

Data analysis was performed using GraphPad Prism Version 10.3.1 (GraphPad Software, USA). Morphological parameters, leaf biochemical traits, and leaf nutrient concentrations were analyzed by one-way analysis of variance (ANOVA), with treatment as the fixed factor. For all morphological parameters, the pot was considered the experimental unit, while for leaf biochemical and nutrient contents, the composite sample was used as the experimental unit. Prior to analysis, the assumptions of ANOVA, including homogeneity of variances (Levene’s test) and normality of residuals (Shapiro–Wilk test) were verified for all datasets. When significance effects were observed, mean comparisons were performed using the Tukey honestly significant difference (HSD) test at a significance level of p < 0.05. Due to the small number of replicates in the biochemical and nutrient analyses (n = 4), a Kruskal–Wallis test was also performed as a confirmatory analysis. For parameters that did not meet the normality assumption, non-parametric tests were assessed, specifically the Kruskal–Wallis test followed by Dunn’s multiple comparisons test. Soil chemical properties were determined from composite samples prepared by pooling soil from all pots within each treatment; therefore, soil data is discussed descriptively. All results are presented as mean ± standard deviation (SD).

3 Results

3.1 Effect of fertilization on lettuce growth

The effects of fertilization on lettuce growth are shown in Figure 1. Overall, both organic amendments (CC or VC) and the commercial fertilization (CF) significantly improved lettuce shoot compared with the unfertilized control (CT).

Mean values (± SD) of morphological parameters measured in lettuce plants (*n* = 8). Different lowercase letters indicate significant difference among treatments at *p* < 0.05 based on the Tukey´s HSD test following one-way ANOVA. Significance levels of the overall model: ns, not significant; **p* < 0.05; ***p* < 0.01; ****p* < 0.001.
Figure 1. Mean values (± SD) of morphological parameters measured in lettuce plants (n = 8). Different lowercase letters indicate significant difference among treatments at p < 0.05 based on the Tukey´s HSD test following one-way ANOVA. Significance levels of the overall model: ns, not significant; *p < 0.05; **p < 0.01; ***p < 0.001.

Among the evaluated parameters, CF resulted in the highest shoot fresh weight, exceeding CT by 115%, whereas plants from CC and VC exhibited similar and intermediate values, with more 80% when compared with CT. Shoot dry biomass, plant height, leaf area, head diameter, plant width, and shoot water content were significantly higher in all fertilized treatments compared with CT (p < 0.05), with no significant differences among CC, VC, and CF (p > 0.05). The number of leaves in CF was significantly higher than in CT, approximately by 20%, but no significant differences were observed among CC and VC either to CF or CT (p > 0.05). Overall, these results indicate that compost and vermicompost supported lettuce growth to levels comparable to commercial fertilization for most morphological traits.

In general, root development responded positively to fertilization (Figure 2). Lettuce plants grown under CC, VC, and CF exhibited significantly greater root length than those grown in CT (approximately 50% higher), with no significant differences among the fertilized treatments (p > 0.05). Root fresh weight was highest in CC, differing significantly from CT (by 47%) and CF (by 39%), whereas VC showed intermediate values and did not differ statistically from any treatment (p > 0.05). Regarding root dry biomass, it was also significantly higher in plants under CC than under CT (ca. 55%), but did not differ from VC and CF (p > 0.05). Overall, organic fertilization, particularly compost, promoted root biomass accumulation to levels comparable to, or exceeding, those achieved with commercial fertilization.

Mean values (±SD) of morphological parameters measured in roots of lettuce plants (*n* = 8). Different lowercase letters indicate significant difference among treatments at *p* < 0.05 based on the Tukey´s HSD test following one-way ANOVA. Significance levels of the overall treatment effect: ns, not significant; **p* < 0.05; ***p* < 0.01; ****p* < 0.001.
Figure 2. Mean values (±SD) of morphological parameters measured in roots of lettuce plants (n = 8). Different lowercase letters indicate significant difference among treatments at p < 0.05 based on the Tukey´s HSD test following one-way ANOVA. Significance levels of the overall treatment effect: ns, not significant; *p < 0.05; **p < 0.01; ***p < 0.001.

3.2 Effect of fertilization on lettuce leaf biochemistry

Leaf biochemical composition was significantly affected by fertilization treatments (Figure 3). Chlorophyll a, chlorophyll b, total chlorophyll, and carotenoid contents were significantly higher in plants grown under CC and CF, compared with CT and VC. Total soluble sugars followed an opposite trend, with CT presenting significantly higher values than CC (ca. 60% higher), VC (30% higher) and CF (62% higher). No significant differences among treatments (p > 0.05) were observed for chlorophyll a/ chlorophyll b and total chlorophyll / carotenoids ratios, and for total protein and total phenolic compounds content.

Mean values (±SD) of biochemical parameters measured in leaves of lettuce plants (*n* = 4 composite samples per treatment). Different lowercase letters indicate significant difference among treatments at *p* < 0.05. Chl *a*, Chl *b*, total Chl, carot., total Chl/carot, total sugar, total protein and total phenols were analyzed by one-way ANOVA followed by Tukey’s HSD test, whereas chl *a*/chl *b* was analyzed by the Kruskal–Wallis test followed by Dunn’s multiple comparisons test. Significance levels of the overall treatment effect: ns, not significant; **p* < 0.05; ***p* < 0.01; ****p* < 0.001.
Figure 3. Mean values (±SD) of biochemical parameters measured in leaves of lettuce plants (n = 4 composite samples per treatment). Different lowercase letters indicate significant difference among treatments at p < 0.05. Chl a, Chl b, total Chl, carot., total Chl/carot, total sugar, total protein and total phenols were analyzed by one-way ANOVA followed by Tukey’s HSD test, whereas chl a/chl b was analyzed by the Kruskal–Wallis test followed by Dunn’s multiple comparisons test. Significance levels of the overall treatment effect: ns, not significant; *p < 0.05; **p < 0.01; ***p < 0.001.

3.3 Effect of fertilization on lettuce nutrient content

Macronutrient concentrations in lettuce leaves differed among the treatments (Figure 4). Leaf N and S concentrations were significantly higher under CF than under CT (approximately 74% and 54% higher, respectively), while CC and VC exhibited similar and intermediate values. Phosphorus concentration was highest in plants grown under CC, intermediate in VC and CF, and lowest in CT. Potassium concentration was significantly higher in CC and VC than in CT and CF. In contrast, no significant differences were observed among treatments for Ca or Mg leaf concentrations (p > 0.05).

Mean values (±SD) of macronutrient content in leaves of lettuce plants (*n* = 4 composite samples per treatment). Different lowercase letters indicate significant differences among treatments at *p* < 0.05. based on the Tukey´s HSD test following one-way ANOVA. Significance levels of the overall treatment effect: ns, not significant; **p* < 0.05; ***p* < 0.01; ****p* < 0.001.
Figure 4. Mean values (±SD) of macronutrient content in leaves of lettuce plants (n = 4 composite samples per treatment). Different lowercase letters indicate significant differences among treatments at p < 0.05. based on the Tukey´s HSD test following one-way ANOVA. Significance levels of the overall treatment effect: ns, not significant; *p < 0.05; **p < 0.01; ***p < 0.001.

Micronutrient concentrations in lettuce leaves were differentially affected by fertilization treatments (Figure 5). Leaf B, Zn, and Cu concentrations remained similar among treatments (p > 0.05). In contrast, Fe concentration was significantly higher under CF than under CT, CC and VC (p = 0.0002), which showed similar concentrations. Leaf Mn also differed among treatments, with CF showing significantly higher values than CT. The organic treatments, CC and VC, exhibited intermediate concentrations that did not differ significantly from either CT or CF.

Mean values (±SD) of micronutrient content in leaves of lettuce plants (*n* = 4 composite samples per treatment). Different lowercase letters indicate significant differences among treatments at *p* < 0.05. B, Fe, Zn, and Cu were analyzed by one-way ANOVA followed by Tukey’s HSD test, whereas Mn was analyzed by the Kruskal–Wallis test followed by Dunn’s multiple comparisons test. Significance levels of the overall treatment effect: ns, not significant; **p* < 0.05; ***p* < 0.01; ****p* < 0.001.
Figure 5. Mean values (±SD) of micronutrient content in leaves of lettuce plants (n = 4 composite samples per treatment). Different lowercase letters indicate significant differences among treatments at p < 0.05. B, Fe, Zn, and Cu were analyzed by one-way ANOVA followed by Tukey’s HSD test, whereas Mn was analyzed by the Kruskal–Wallis test followed by Dunn’s multiple comparisons test. Significance levels of the overall treatment effect: ns, not significant; *p < 0.05; **p < 0.01; ***p < 0.001.

3.4 Soil chemical properties at the end of the experiment

Soil chemical properties showed differences among fertilization treatments at the end of the experiment (Table 3). Soil pH was lowest under commercial fertilization (CF), whereas soils amended with compost (CC) and vermicompost (VC) maintained values closer to those of the unfertilized control (CT). Electrical conductivity increased in all fertilized treatments relative to CT, by approximately 120% in CC, 166% in VC, and 137% in CF. Likewise, cation exchange capacity (CEC) was highest in CC, followed by VC, whereas CT and CF showed lower values. In contrast, soil organic matter content and total N remained relatively similar among treatments. Regarding extractable P and K, their concentrations were markedly higher in organically amended soils, with VC showing the highest extractable P concentration and CC the highest extractable K concentration. Similarly, exchangeable Ca, Mg, and K tended to be higher under CC and VC than under CT and CF. In terms of micronutrients, extractable B and Zn were higher in soils receiving organic amendments, whereas Mn showed the opposite trend, with lower concentrations under CC, VC, and CF than in CT. Extractable Cu and Fe showed only minor variation among treatments. Total trace element concentrations (Zn, Cu, Pb, Cd, Cr, Ni, and Hg) remained low and were comparable across treatments.

Table 3. Mean chemical characteristics (±SD) of the soil at the end of the experiment.

Soil characteristicsCTCCVCCF
pH (H20)5.94 ± 0.065.80 ± 0.055.77 ± 0.035.38 ± 0.04
Organic matter (%)1.77 ± 0.172.15 ± 0.502.04 ± 0.111.88 ± 0.14
Electrical conductivity (dS m−1)0.030 ± 0.0020.066 ± 0.0110.080 ± 0.0050.071 ± 0.007
CEC (cmolc kg−1)3.36 ± 0.184.49 ± 0.424.19 ± 0.283.58 ± 0.08
Exchangeable Ca (cmolc kg−1)2.34 ± 0.123.22 ± 0.343.05 ± 0.202.44 ± 0.05
Exchangeable Mg (cmolc kg−1)0.844 ± 0.0470.998 ± 0.0960.919 ± 0.0510.663 ± 0.021
Exchangeable K (cmolc kg−1)0.076 ± 0.0060.139 ± 0.0190.103 ± 0.0040.088 ± 0.009
Exchangeable Na (cmolc kg−1)0.070 ± 0.0080.071 ± 0.0080.071 ± 0.0030.041 ± 0.010
Total N (g kg−1)1.07 ± 0.101.25 ± 0.251.20 ± 0.081.11 ± 0.08
Extractable P (mg P2O5 kg−1)26.1 ± 2.262.6 ± 12.392.8 ± 13.639.9 ± 4.2
Extractable K (mg K2O kg−1)37.6 ± 2.266.2 ± 8.850.2 ± 1.943.2 ± 4.6
Extractable micronutrients
B (mg B kg−1)0.040 ± 0.0010.105 ± 0.0110.103 ± 0.0090.056 ± 0.009
Cu (mg Cu kg−1)2.56 ± 0.132.76 ± 0.102.76 ± 0.172.77 ± 0.11
Zn (mg Zn kg−1)1.28 ± 0.183.61 ± 0.253.68 ± 0.561.80 ± 0.09
Fe (mg Fe kg−1)125 ± 3135 ± 2135 ± 4134 ± 9
Mn (mg Mn kg−1)69.6 ± 4.350.3 ± 0.858.7 ± 3.847.7 ± 1.8
Trace elements
Zn (mg Zn kg−1)36.8 ± 3.038.6 ± 1.242.4 ± 5.735.9 ± 0.6
Cu (mg Cu kg−1)10.0 ± 0.811.3 ± 0.810.8 ± 0.710.9 ± 1.6
Pb (mg Pb kg−1)5.7 ± 0.35.3 ± 0.25.9 ± 0.75.1 ± 0.1
Cd (mg Cd kg−1)0.062 ± 0.0010.071 ± 0.0010.062 ± 0.0220.058 ± 0.000
Cr (mg Cr kg−1)8.8 ± 0.98.8 ± 0.47.7 ± 1.78.4 ± 0.6
Ni (mg Ni kg−1)5.1 ± 0.55.3 ± 0.25.5 ± 0.65.1 ± 0.3
Hg (μg Hg kg−1)6.9 ± 0.96.4 ± 0.06.8 ± 0.27.1 ± 0.5

4 Discussion

The present study represents a single 55-day growing cycle, capturing primarily short-term plant and soil responses. It demonstrates that pelletized compost and vermicompost produced from vineyard pruning residues and sewage sludge supported lettuce growth at levels comparable to commercial fertilization, despite differences in nutrient inputs among treatments, while showing favorable trends in several soil chemical properties. Both organic amendments significantly enhanced shoot and root development compared with the unfertilized control, confirming their capacity to supply nutrients for lettuce production. Although commercial fertilization resulted in the highest shoot fresh weight, compost and vermicompost performed similarly for most morphological traits, including plant height, leaf area, head diameter, shoot dry biomass, shoot water content, and root length. These findings indicate that pelletized organic amendments can sustain satisfactory lettuce growth despite their different nutrient release dynamics compared to commercial fertilizer. This is in agreement with previous studies on lettuce (Hernández et al., 2016; Theourn et al., 2021; Tütüncü et al., 2025) and other horticultural and field crops, such as cowpea (Badar et al., 2015), rice (Marti-Jerez et al., 2023), and celery (Daneshvar et al., 2023).

The greater shoot fresh biomass observed under commercial fertilization should not be interpreted as evidence of consistently superior overall growth, given the absence of significant differences in shoot dry biomass, plant height, plant width, leaf area, head diameter, and shoot water content among the fertilized treatments. The similar shoot water content across treatments also indicates that the higher fresh biomass under commercial fertilization was not simply attributable to greater tissue hydration. Since the application rate of the organic amendments was limited by Zn content to comply with legal limits, and was applied at a higher rate than the commercial fertilizer, the higher shoot fresh biomass under commercial fertilization cannot be attributed to a greater total nutrient input. Instead, it likely reflects differences in nutrient availability and release dynamics. The commercial fertilizer typically possesses a higher proportion of readily available inorganic nutrients (Zapałowska et al., 2025), particularly N, which promotes rapid shoot expansion and fresh biomass accumulation (Acar et al., 2025). In contrast, nutrient supply from organic fertilizers occurs more gradually (Shaji et al., 2021; Asadu et al., 2024; Oliveira et al., 2025), often stimulating greater investment in root growth to enhance nutrient acquisition (Chatzistathis et al., 2025; Ray et al., 2025). This response is consistent with the present root morphological data, where compost and vermicompost treatments exhibited root length and biomass comparable to, or slightly higher than, those under commercial fertilization. Enhanced root development under organic fertilization has been widely reported (Bilalis et al., 2015; Pu et al., 2016; Esteves et al., 2020; Ray et al., 2025; Wahidurromdloni et al., 2025) and is commonly linked to improved soil structure (Ray et al., 2025; Khan et al., 2026), increased microbial and enzymatic activity (Lu et al., 2025; Zapałowska et al., 2025), and more sustained nutrient availability (Lu et al., 2025; Ray et al., 2025). Consequently, short-term biomass production may not fully reflect the agronomic value of organic amendments, whose benefits frequently extend beyond a single growing cycle through gradual nutrient release and improvements in soil fertility (Bonanomi et al., 2020; Zhao et al., 2021).

Leaf biochemical traits further support the absence of physiological constraints under organic fertilization. Variations in chlorophyll and carotenoid concentrations among treatments appear to mirror differences in growth dynamics rather than limitations in photosynthetic capacity. The lack of significant differences in the chlorophyll a to chlorophyll b ratio and the total chlorophyll to total carotenoids ratio, commonly used as indicators of photosynthetic apparatus integrity (Ljubej et al., 2021), suggests that photosynthetic functioning and nutritional balance were preserved across treatments (Oliveira et al., 2025). The higher pigment concentrations observed under compost and commercial fertilizations are likely associated with nutrient availability for pigment synthesis, although the specific mechanisms cannot be fully elucidated based solely on the parameters measured in the present study. Moreover, the absence of significant differences in total phenolic compounds and protein content indicates that neither compost nor vermicompost induced oxidative or metabolic stress (Monteiro et al., 2024), reinforcing their suitability as nutrient sources for lettuce production.

Leaf nutrient composition showed that compost and vermicompost maintained macronutrient concentrations comparable to those achieved under commercial fertilization, despite the higher amounts of N, P and K supplied by the organic amendments. The apparent lack of leaf nutrient response to these higher inputs could be attributed to differences in the availability of nutrients to plants. Nutrients in organic amendments are generally released more slowly and may require mineralization before becoming available for plant uptake (Haufiku et al., 2025). In addition, the sandy-loam soil with relatively low organic matter used in the experiment could also have influenced nutrient retention and availability (Ramya et al., 2026). Nevertheless, the comparable leaf macronutrient concentrations under organic and commercial fertilization suggest that both amendments provided a substantial nutrient supply during the 55-day growing cycle. Similar results were reported by Lin et al. (2019), who observed that organic fertilizers supplied nutrient amounts comparable to chemical fertilizers in tea orchards. Among macronutrients, K concentration was markedly higher under organic fertilization, likely reflecting the high K content and the greater proportions of exchangeable forms typically supplied by organic matter and its decomposition products (Daneshvar et al., 2023). These processes increase nutrient availability in the rhizosphere, thereby promoting K uptake and accumulation in plant tissues (Mahdy, 2011). With respect to micronutrients, compost and vermicompost maintained B, Zn and Cu concentrations at levels comparable to those observed under commercial fertilization and in the unfertilized control, indicating that fertilization did not alter the accumulation of these elements. In contrast, Fe and Mn were higher under commercial fertilization, which could partially contribute to the higher shoot fresh biomass recorded in this treatment, given the central role of these elements in chlorophyll synthesis and photosynthetic processes (Yang et al., 2025). Moreover, the higher Fe and Mn concentrations under commercial fertilization may be partly associated with the lower soil pH (5.38) (Ingall et al., 2018; Arrobas et al., 2023; Wang et al., 2025; Shevela and Nonomura, 2026). Under acidic conditions, metal cations such as Mn, Zn, Fe, and Cu become more soluble (Broadley et al., 2012), and this could have promoted greater Mn and Fe uptake by plants. Overall, these results indicate that organic fertilization promoted a more balanced nutritional profile in lettuce leaves, reinforcing the central role of soil chemical conditions in regulating nutrient availability and uptake (Serri et al., 2021). However, it is important to acknowledge that the assessment of this nutritional profile is not complete due to the absence of leaf nitrate measurements. Nitrate content is particularly relevant in leafy vegetables like lettuce, due to its health implications and links with agricultural practices (Nguyen et al., 2025). Fertilization, particularly N fertilization, is commonly associated with nitrate accumulation (Liu et al., 2014). Among fertilizers, organic fertilizers, due to their slower mineralization and more gradual N release, generally promote lower nitrate accumulation in lettuce tissues compared to rapid-release synthetic fertilizers (García-Rández et al., 2025; Nguyen et al., 2025).

Comparison between the initial soil characterization and the final soil analyses indicates that the 55-day growing cycle resulted in measurable changes in several soil chemical properties, particularly soil pH, extractable P and K, and cation exchange capacity. Commercial fertilization resulted in the greatest decline in soil pH, whereas compost and vermicompost maintained values closer to those of the unfertilized control, suggesting that organic amendments mitigated soil acidification. A smaller decline in soil pH was also observed in the unfertilized control, indicating that part of the acidification could be attributed to processes occurring during plant growth, such as rhizosphere activity, nitrification of native soil N, and CO2 production from root and microbial respiration. Soil acidification associated with repeated synthetic fertilizer use is a well-recognized process that may contribute to long-term soil degradation (Arrobas et al., 2023). Although electrical conductivity increased in all fertilized treatments, values remained well below the threshold detrimental for lettuce growth (1.1–2.0 mS cm−1) (Zuzunaga-Rosas et al., 2024).

Soil organic matter, a key indicator of soil quality (Santos et al., 2025), remained relatively stable throughout the experiment, likely due to the short duration of lettuce production (55 days), although slightly higher values were observed in soils receiving compost and vermicompost. This trend suggests a potential contribution of compost and vermicompost to soil fertility and quality, as previously reported for other organic amendments (Cardarelli et al., 2023). Similarly, extractable P and K tended to be higher in soils amended with organic fertilizers than in the unfertilized control, indicating that both compost and vermicompost enhanced the pool of plant-available nutrients through organic matter mineralization (Syarifinnur et al., 2020; Aina et al., 2025). Compost and vermicompost are nutrient-rich materials that introduce substantial amounts of organic matter into the soil (Amaya-Gómez et al., 2025). During decomposition, besides nutrient mineralization, they release organic acids that promote weathering and nutrient solubilization through acid dissolution processes (Syarifinnur et al., 2020). Compared with commercial fertilization, the application of compost and vermicompost resulted in higher available P and K as confirmed by the higher leaf contents, suggesting that the intrinsic nutrient composition of these organic fertilizers played a decisive role in nutrient availability (Arrobas et al., 2023). In addition, organic fertilization improved soil cation exchange capacity relative to the unfertilized control and commercial fertilization, thereby enhancing nutrient adsorption, buffering capacity, and overall soil fertility, key attributes for sustaining productivity in intensive horticultural systems (Suvendran et al., 2025). However, given the short duration of the present experiment, these responses should be regarded as short-term indications rather than evidence of persistent changes in soil quality. Repeated applications of organic amendments may generate cumulative effects that are not detectable within a single crop cycle, including increases in soil organic carbon, improvements in soil fertility, and changes in soil microbial communities capable of supporting high plant yield under intensive agricultural systems (Bonanomi et al., 2020; Zhao et al., 2021).

Trace element concentrations remained low in soils amended with compost or vermicompost, with no indication of marked accumulation during the 55-day experiment, despite the inclusion of sewage sludge as a feedstock. This finding confirms that properly processed sewage sludge can be successfully incorporated into high-value organic amendments without compromising soil quality (Yatoo et al., 2025). The results are consistent with previous studies demonstrating that properly treated organic residues can be safely recycled without environmental or agronomic risks (Arrobas et al., 2023).

Although vermicompost is often associated with enhanced nutrient availability and biological activity compared to the compost (Lin et al., 2019; Al-Tawarah et al., 2024; Tan et al., 2025), the amendment with vermicompost had no competitive advantage compared to compost in the present study. This may be related to their similar nutrient composition and application rate. Moreover, the short duration of the experiment may have limited the expression of differences associated with nutrient mineralization and the biological activity of the vermicompost.

From a circular economy perspective, the application rate used in this experiment corresponded to 20 g FW of organic amendment per pot, equivalent to approximately 20 t FW ha−1 on a soil-mass basis. The conversion of vineyard pruning residues and sewage sludge into agronomically usable compost and vermicompost provides a pathway for recycling organic matter and nutrients into horticultural production systems. Pelletization may offer practical advantages in terms of handling, transport, storage, and field application, and may also influence nutrient-release dynamics and mineralization rates (Sun-inthara et al., 2024). However, pellet durability, storage stability, energy requirements, and economic performance were not evaluated in the present study, which deserves further assessment, including life-cycle and cost-benefit analyses to determine the overall environmental and economic advantages of the pelletized products.

Some methodological limitations should be considered when interpreting the present results. Leaf material was pooled in pairs for biochemical and mineral analyses due to the limited biomass available per plant, reducing the effective number of independent samples and preventing assessment of plant-to-plant variability within each composite sample. Soil chemical properties were also determined from composite samples obtained by pooling soil from all pots within each treatment, and were therefore interpreted descriptively. These limitations should be addressed in future studies designed to validate the present findings under longer-term and field conditions.

5 Conclusion

This study showed that pelletized compost and vermicompost, derived from vineyard pruning residues and sewage sludge, supported lettuce growth under the conditions tested. Although commercial fertilization resulted in slightly higher shoot fresh weights, organic amendments achieved comparable performance for most morphological traits while providing benefits to soil fertility, including improvements in organic matter, nutrient availability, and cation exchange capacity.

The maintenance of a balanced leaf macro- and micronutrient concentrations, together with the absence of trace metal accumulation in soil, supports the agronomic use of these pelletized organic amendments. Their production from agricultural and urban residues further contributes to waste valorization and circular economy strategies, while offering a sustainable option for improving soil fertility and nutrient management in intensive horticultural systems.

Future research should evaluate these organic amendments under field conditions over multiple growing seasons and across contrasting soil and climatic conditions to assess their long-term effects on soil fertility, nutrient availability and nutritional profile, crop productivity, and economic feasibility of the pelletized products.

Generative AI statement

The author(s) declared that Generative AI was not used in the creation of this manuscript.

Any alternative text (alt text) provided alongside figures in this article has been generated by Frontiers with the support of artificial intelligence and reasonable efforts have been made to ensure accuracy, including review by the authors wherever possible. If you identify any issues, please contact us.

Publisher’s note

All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article, or claim that may be made by its manufacturer, is not guaranteed or endorsed by the publisher.

Supplementary material

The Supplementary material for this article can be found online at: https://www.frontiersin.org/articles/10.3389/fsufs.2026.1948663/full#supplementary-material

Supplementary material Supplementary material at the source

Footnotes

Edited by: Mohd Huzairi Mohd Zainudin, University of Putra Malaysia, Malaysia

Reviewed by: Rosa Ana Rodriguez, Universidad Nacional de San Juan, Argentina

Richard Osei, Gansu Agricultural University, China

Statements

Conflict of interest

The author(s) declared that this work was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

Funding

The author(s) declared that financial support was received for this work and/or its publication. The research reported in this manuscript was funded exclusively by “Vine & Wine Portugal-Driving Sustainable Growth Through Smart Innovation”, co-financed by the “Recovery and Resilience Plan (PRR)” and the “European Union’s NextGenerationEU” funds, within “Portugal’s Recovery and Resilience Plan” (project number C644866286-00000011).

Data availability

The original contributions presented in the study are included in the article/Supplementary material, further inquiries can be directed to the corresponding author.

Author contributions

MM: Methodology, Formal analysis, Writing – original draft, Writing – review & editing, Investigation, Conceptualization. EN-G: Writing – review & editing, Investigation. L-TD: Writing – review & editing, Investigation. SP: Investigation, Writing – review & editing. ZB: Investigation, Writing – review & editing. HL: Investigation, Writing – review & editing. TA: Writing – review & editing, Investigation. CM: Writing – review & editing, Investigation. AC: Writing – review & editing. JC: Writing – review & editing. GM: Writing – review & editing, Conceptualization. JS: Writing – review & editing. PO: Funding acquisition, Supervision, Writing – review & editing. MR: Conceptualization, Writing – review & editing.

Acknowledgements

The authors acknowledge the support from FCT—Portuguese Foundation for Science and Technology, under the projects UID/04033/2025: Centre for the Research and Technology of Agro-Environmental and Biological Sciences (https://doi.org/10.54499/UID/04033/2025) and LA/P/0126/2020 (https://doi.org/10.54499/LA/P/0126/2020), UIDP/50006/2020 (REQUIMTE, DOI: 10.54499/UIDP/50006/2020) and UIDB/50006/2020 (REQUIMTE, DOI: 10.54499/UIDB/50006/2020), which provided the laboratory facilities for this research.

References

  1. Acar M., Wahab T. S., Karaca K. Ö., Işık M., Sariyev A., Ortas I. (2025). Exposing how long-term organic and inorganic fertilizers affect the physical characteristics of soil. J. Soil Sci. Plant Nutr. 25, 5187 – 5201. doi: doi:10.1007/s42729-025-02457-1
  2. Adebanjo-Aina O., Oludoye O. (2025). Impact of nitrogen fertiliser usage in agriculture on water quality. Pollutants 5: 21. doi: doi:10.3390/pollutants5030021
  3. Aina O. E., Mugivhisa L. L., Olowoyo J. O., Obi L. C. (2025). Evaluation of mineral contents of lettuce and carrot harvested from soil treated with organic and inorganic fertilizers. Agriculture 15: 656. doi: doi:10.3390/agriculture15060656
  4. Al-Tawarah B., Alasasfa M. A., Mahadeen A. Y. (2024). Efficacy of compost and vermicompost on growth, yield and nutrient content of common beans crop (Phaseolus vulgaris L.). J. Ecol. Eng. 25, 215 – 226. doi: doi:10.12911/22998993/176862
  5. Almaramah S. B., Abu-Elsaoud A. M., Alteneiji W. A., Albedwawi S. T., El-Tarabily K. A., Al Raish S. M. (2024). The impact of food waste compost, vermicompost, and chemical fertilizers on the growth measurement of red radish (Raphanus sativus): a sustainability perspective in the United Arab Emirates. Foods 13: 1608. doi:,. doi:10.3390/foods13111608
  6. Alromian F. M. (2020). Effect of type of compost and application rate on growth and quality of lettuce plant. J. Plant Nutr. 43, 2797 – 2809. doi: doi:10.1080/01904167.2020.1793185
  7. Amaya-Gómez C. V., Flórez-Martínez D. H., Cayuela M. L., Tortosa G. (2025). Compost and vermicompost improve symbiotic nitrogen fixation, physiology and yield of the Rhizobium-legume symbiosis: a systematic review. Appl. Soil Ecol. 210: 106051. doi: doi:10.1016/j.apsoil.2025.106051
  8. Anderson J. P. E. (1982). “ Soil respiration,” in Methods of Soil Analysis, ed. Page A. L.. Chichester, UK: John Wiley & Sons, Ltd, 831 – 871.
  9. Arrobas M., Andrade M., Raimundo S., Mazaro S. M., Rodrigues M. A. (2023). Lettuce response to the application of two commercial leonardites and their effect on soil properties in a growing medium with nitrogen as the main limiting factor. J. Plant Nutr. 46, 4280 – 4294. doi: doi:10.1080/01904167.2023.2225557
  10. Asadu C. O., Ezema C. A., Ekwueme B. N., Onu C. E., Onoh I. M., Adejoh T.. (2024). Enhanced efficiency fertilizers: overview of production methods, materials used, nutrients release mechanisms, benefits and considerations. Environ. Pollut. Manag. 1, 32 – 48. doi: doi:10.1016/j.epm.2024.07.002
  11. Atiyeh R. M., Domínguez J., Subler S., Edwards C. A. (2000). Changes in biochemical properties of cow manure during processing by earthworms (Eisenia andrei, Bouché) and the effects on seedling growth. Pedobiologia 44, 709 – 724. doi: doi:10.1078/S0031-4056(04)70084-0
  12. Badar R., Khan M., Batool B., Shabbir S. (2015). Effects of organic amendments in comparison with chemical fertilizer on cowpea growth. Intern. J. Appl. Res. 1, 66 – 71.
  13. Bhat S. A., Singh J., Vig A. P. (2017). Instrumental characterization of organic wastes for evaluation of vermicompost maturity. J. Anal. Sci. Technol. 8: 2. doi: doi:10.1186/s40543-017-0112-2
  14. Bilalis D., Karkanis A., Angelopoulou F., Travlos I., Antoniadis A., Ntatsi G.. (2015). Effect oforganic and mineral fertilization on root growth and mycorrhizal colonization of pea crops (Pisum sativum L.). Bull. Univ. Agric. Sci. Vet. Med. Cluj-Napoca Hortic. 72, 288 – 294. doi: doi:10.15835/buasvmcn-hort:11497
  15. Bonanomi G., De Filippis F., Zotti M., Idbella M., Cesarano G., Al-Rowaily S.. (2020). Repeated applications of organic amendments promote beneficial microbiota, improve soil fertility and increase crop yield. Appl. Soil Ecol. 156: 103714. doi: doi:10.1016/j.apsoil.2020.103714
  16. Bradford M. M. (1976). A rapid and sensitive method for the quantitation of microgram quantities of protein utilizing the principle of protein-dye binding. Anal. Biochem. 72, 248 – 254. doi:,. doi:10.1016/0003-2697(76)90527-3
  17. Broadley M., Brown P., Cakmak I., Rengel Z., Zhao F. (2012). “ Function of nutrients, micronutrients,” in Marschner’s Mineral Nutrition of Higher Plants, ed. Marschner P. (London: Elsevier), 191 – 248.
  18. Cardarelli M., El Chami A., Iovieno P., Rouphael Y., Bonini P., Colla G. (2023). Organic fertilizer sources distinctively modulate productivity, quality, mineral composition, and soil enzyme activity of greenhouse lettuce grown in degraded soil. Agronomy 13: 194. doi: doi:10.3390/agronomy13010194
  19. Castellini M., Bondì C., Leogrande R., Giglio L., Vitti C., Mastrangelo M.. (2025). Evaluating the effects of compost, vermicompost, and biochar on physical quality of sandy-loam soils. Appl. Sci. 15: 3392. doi: doi:10.3390/app15063392
  20. Chatzistathis T., Sarropoulou V., Papaioannou E., Giannakoula A. (2025). Inorganic and organic fertilization effects on the growth, nutrient uptake, chlorophyll fluorescence and fruit quality in Solanum melongena L. plants. Agronomy 15: 872. doi: doi:10.3390/agronomy15040872
  21. Cozzolino E., Salluzzo A., Piano L., Tallarita A. V., Cenvinzo V., Cuciniello A.. (2023). Effects of the application of a plant-based compost on yield and quality of industrial tomato (Solanum lycopersicum L.) grown in different soils. Appl. Sci. 13: 8401. doi: doi:10.3390/app13148401
  22. Daneshvar H., Babalar M., Díaz-Pérez J. C., Nambeesan S., Delshad M., Tabrizi L. (2023). Evaluation of organic and mineral fertilizers on plant growth, minerals, and postharvest quality of celery (Apium graveolens L.). J. Plant Nutr. 46, 1712 – 1729. doi: doi:10.1080/01904167.2022.2097921
  23. Dayan A., Bayram C. (2025). Comparative evaluation of conventional and vermicompost fertilizers on broccoli (Brassica oleracea L.) in different agroecological zones. Folia Hort. 37, 65 – 77. doi: doi:10.2478/fhort-2025-0006
  24. Diatta A. A., Bassène C., Manga A. G. B., Abaye O., Thomason W., Battaglia M.. (2023). Integrated use of organic amendments increased mungbean (Vigna radiata (L.) Wilczek) yield and its components compared to inorganic fertilizers. Urban Agric. Reg. Food Syst. 8: e20048. doi: doi:10.1002/uar2.20048
  25. Egnér H., Riehm H., Domingo W. (1960). Untersuchungen über die chemische bodenanalyse als grundlage für die beurteilung des nährstoffzustandes der böden. II. Chemische extraktionsmethoden zur phosphor-und kaliumbestimmung. K. Lantbrukshögskolans Ann. 26, 199 – 215.
  26. Esteves G. F., Souza K. R. D., Bressanin L. A., Andrade P. C. C., Júnior V. V., Reis P. E.. (2020). Vermicompost improves maize, millet and sorghum growth in iron mine tailings. J. Environ. Manag. 264: 110468. doi:,. doi:10.1016/j.jenvman.2020.110468
  27. FAO (Food and Agriculture Organization of the United Nations) (2024). Standard Operating Procedure for Boron Determination in Soil: Hot Water Extraction. Rome: FAO.
  28. Gaga I., Pacurar F., Vaida I., Plesa A., Rotar I. (2022). Responses of diversity and productivity to organo-mineral fertilizer inputs in a high-natural-value grassland, Transylvanian Plain, Romania. Plants 11: 1975. doi:,. doi:10.3390/plants11151975
  29. Garcia L. D., Anoruo A. O., Nelson S. D., Nsofor B. N., Turner B. L., Holland P. W. (2026). Agronomically applied nitrogen has the same fate irrespective of source: a comprehensive review of synthetic and organic soil nitrogen sources. J. Agric. Food Res. 28: 102983. doi: doi:10.1016/j.jafr.2026.102983
  30. García-Rández A., Orden L., Sánchez-Méndez S., Andreu-Rodríguez F. J., Sáez-Tovar J. A., Martínez-Sabater E.. (2025). Comparative evaluation of organic and synthetic fertilizers on lettuce yield and metabolomic profiles. Horticulturae 11: 1421. doi: doi:10.3390/horticulturae11121421
  31. González-Miranda I., Vidal K., Peñaloza P. (2021). Comparing nitrate leaching in lettuce crops cultivated under agroecological, transition, and conventional agricultural management in central Chile. Chil. J. Agric. Res. 81, 210 – 219. doi: doi:10.4067/S0718-58392021000200210
  32. Goswami L., Nath A., Sutradhar S., Bhattacharya S. S., Kalamdhad A., Vellingiri K.. (2017). Application of drum compost and vermicompost to improve soil health, growth, and yield parameters for tomato and cabbage plants. J. Environ. Manag. 200, 243 – 252. doi:,. doi:10.1016/j.jenvman.2017.05.073
  33. Haufiku A. M., Ausiku P. A., Huttunen S. (2025). The role of organic and inorganic soil amendments on soil physicochemical properties and wheat (Triticum aestivum L.) agronomic performance in Semi-arid North-Central Namibia: a review. Discov. Agric. 3: 215. doi: doi:10.1007/s44279-025-00383-5
  34. Hernández T., Chocano C., Moreno J. L., García C. (2016). Use of compost as an alternative to conventional inorganic fertilizers in intensive lettuce (Lactuca sativa L.) crops—effects on soil and plant. Soil Tillage Res. 160, 14 – 22. doi: doi:10.1016/j.still.2016.02.005
  35. Ingall E. D., Feng Y., Longo A. F., Lai B., Shelley R. U., Landing W. M.. (2018). Enhanced iron solubility at low pH in global aerosols. Atmosphere 9: 201. doi: doi:10.3390/atmos9050201
  36. Irigoyen J. J., Einerich D. W., Sánchez-Díaz M. (1992). Water stress induced changes in concentrations of proline and total soluble sugars in nodulated alfalfa (Medicago sativa) plants. Physiol. Plant. 84, 55 – 60. doi: doi:10.1111/j.1399-3054.1992.tb08764.x
  37. ISO (2018). International Standardization Organization—11260. Soil Quality—Determination of Effective Cation Exchange Capacity and Base Saturation Level using Barium Chloride Solution. Geneva: ISO.
  38. ISO (2020). International Standardization Organization—54321. Soil, Treated Biowaste, Sludge and Waste—Digestion of Aqua Regia Soluble Fractions of Elements. Geneva: ISO.
  39. ISO (2021). International Standardization Organization—10390. Soil, Treated Biowaste and Sludge—Determination of pH. Geneva: ISO.
  40. ISO (2025). International Standardization Organization—1265. Environmental Solid Matrices—Determination of the Specific Electrical Conductivity. Geneva: ISO.
  41. IUSS Working Group WRB (2022). World Reference Base for Soil Resources. International Soil Classification System for Naming Soils and Creating Legends for Soil Maps. 4th edition. Vienna: International Union of Soil Sciences (IUSS).
  42. Jatav H. S., Rajput V. D. (2025). Sustainable nutrient management under climate change. Front. Agron. 7: 1625151. doi: doi:10.3389/fagro.2025.1625151
  43. Jesus M., Romaní A., Mata F., Domingues L. (2022). Current options in the valorisation of vine pruning residue for the production of biofuels, biopolymers, antioxidants, and bio-composites following the concept of biorefinery: a review. Polymers 14: 1640. doi:,. doi:10.3390/polym14091640
  44. Kavvadias V., Ioannou Z., Vavoulidou E., Paschalidis C. (2023). Short term effects of chemical fertilizer, compost and zeolite on yield of lettuce, nutrient composition and soil properties. Agriculture 13: 1022. doi: doi:10.3390/agriculture1305102
  45. Kebibeche H., Khelil O., Kacem M., Kaid Harche M. (2019). Addition of wood sawdust during the co-composting of sewage sludge and wheat straw influences seeds germination. Ecotoxicol. Environ. Saf. 168, 423 – 430. doi: doi:10.1016/J.ECOENV.2018.10.075
  46. Khan A. Q., Guo C., Liu Y., Ma H., Ullah R., Li Z.. (2026). Organic fertilization enhances soil quality and stabilizes functional fungal networks in semi-arid Astragalus agroecosystems. Appl. Soil Ecol. 217: 106587. doi: doi:10.1016/j.apsoil.2025.106587
  47. Kjeldahl J. (1883). Neue methode zur bestimmung des stickstoffs in organischen körpern. Z. Anal. Chem. 22, 366 – 382.
  48. Krasilnikov P., Taboada M. A., Amanullah (2022). Fertilizer use, soil health and agricultural sustainability. Agriculture 12: 462. doi: doi:10.3390/agriculture12040462
  49. Lakanen E., Erviö R. A. (1971). Comparison of eight extradants for the determination of plant available micronutrients in soils. Acta Agr. Fenn. 123, 223 – 232.
  50. Lara-Capistrán L., Zulueta-Rodríguez R., Murillo-Amador B., Romero-Bastidas M., Rivas-García T., Hernández-Montiel L. G. (2020). Agronomic response of sweet pepper (Capsicum annuum L.) to application of Bacillus subtilis and vermicompost in greenhouse. Terra Latinoam. 38, 693 – 704. doi: doi:10.28940/terra.v38i3.737
  51. Libutti A., Trotta V., Rivelli A. R. (2020). Biochar, vermicompost, and compost as soil organic amendments: influence on growth parameters, nitrate and chlorophyll content of swiss chard (Beta vulgaris L. var. cycla). Agronomy 10: 346. doi: doi:10.3390/agronomy10030346
  52. Lichtenthaler H. K. (1987). Chlorophylls and carotenoids: pigments of photosynthetic biomembranes. Meth. Enzymol. 148, 350 – 382. doi: doi:10.1016/0076-6879(87)48036-1
  53. Lin W., Lin M., Zhou H., Wu H., Li Z., Lin W. (2019). The effects of chemical and organic fertilizer usage on rhizosphere soil in tea orchards. PloS One 14: e0217018. doi:,. doi:10.1371/journal.pone.0217018
  54. Liu Y., Lan X., Hou H., Ji J., Liu X., Lv Z. (2024). Multifaceted ability of organic fertilizers to improve crop productivity and abiotic stress tolerance: review and perspectives. Agronomy 14: 1141. doi: doi:10.3390/agronomy14061141
  55. Liu C.-W., Sung Y., Chen B.-C., Lai H.-Y. (2014). Effects of nitrogen fertilizers on the growth and nitrate content of lettuce (Lactuca sativa L.). Int. J. Environ. Res. Public Health 11, 4427 – 4440. doi:,. doi:10.3390/ijerph110404427
  56. Ljubej V., Redovnikovic I. R., Salopek-Sondi B., Smolko A., Roje S., Samec D. (2021). Chilling and freezing temperature stress differently influence glucosinolates content in Brassica oleracea var. acephala. Plants 10: 1305. doi:,. doi:10.3390/plants10071305
  57. Lopes H., Gonçalves E., Morais M., Coimbra A., Sousa J., Oliveira P.. (2026). Agronomic valorization of sewage sludge through composting and liming. Appl. Sci. 16: 4805. doi: doi:10.3390/app16104805
  58. Lu W., Zhou Y., Ma X., Gao J., Guo J., Fan X.. (2025). Impacts of organic fertilizer substitution on soil ecosystem functions: synergistic effects of nutrients, enzyme activities, and microbial communities. Agronomy 15: 2798. doi: doi:10.3390/agronomy15122798
  59. Mahdy A. M. (2011). Soil properties and wheat growth and nutrients as affected by compost amendment under saline water irrigation. Pedosphere 21, 773 – 781. doi: doi:10.1016/S1002-0160(11)60181-1
  60. Marti-Jerez K., Català-Forner M., Tomàs N., Murillo G., Ortiz C., Sánchez-Torres M. J.. (2023). Agronomic performance and remote sensing assessment of organic and mineral fertilization in rice fields. Front. Plant Sci. 14: 1230012. doi:,. doi:10.3389/fpls.2023.1230012
  61. Marutani M., Clemente S. (2021). Compost-based growing media improved yield of leafy lettuce in pot culture. Agronomy 11: 1762. doi: doi:10.3390/agronomy11091762
  62. Monteiro S. S., Martins L. P., Araújo R. C., Silva E. A., Monteiro S. S. (2024). Different sources of nutrients in the production and quality of “Veneranda” curly lettuce. Hortic. Bras. 42: e2616. doi: doi:10.1590/s0102-0536-2024-e2616
  63. Mupambwa H. A., Ruben E. N. M., Haneklaus N. H., Handura B., Howoses V. A., Ait Brahim J.. (2026). Vermicomposting of camel (Camelus dromedarius) manure with fly ash and microbial inoculants: effects on nutrients and heavy metals. Agriculture 16: 654. doi: doi:10.3390/agriculture16060654
  64. Muscolo A., Marra F., Canino F., Maffia A., Mallamaci C., Russo M. (2022). Growth, nutritional quality and antioxidant capacity of lettuce grown on two different soils with sulphur-based fertilizer, organic and chemical fertilizers. Sci. Hortic. 305: 111421. doi: doi:10.1016/j.scienta.2022.111421
  65. Ngo P. T., Rumpel C., Thu T. D., Henry-des-Tureaux T., Dang D. K., Jouquet P. (2014). Use of organic substrates for increasing soil organic matter quality and carbon sequestration of tropical degraded soil: a 3-year mesocosms experiment. Carbon Manag. 5, 155 – 168. doi: doi:10.1080/17583004.2014.912868
  66. Nguyen N. T. T., Nguyen B. X., Habibi N., Dabirimirhosseinloo M., Oliveira L. A., Terada N.. (2025). Effect of organic and synthetic fertilizers on nitrate, nitrite, and vitamin C levels in leafy vegetables and herbs. Plants 14: 917. doi:,. doi:10.3390/plants14060917
  67. Olaniyan O. O., Abagale F. K., Adongo T. A. (2026). Effect of organic fertilizer and irrigation regimes on lettuce production in Northern Ghana. Heliyon 12: e45248. doi: doi:10.1016/j.heliyon.2026.e45248
  68. Oliveira A. M. F., Mendonça V., Amorim P. E. C., Freire R. I. S., Silva L. R. B., Silva D. E. G.. (2025). Organic and mineral fertilization on the photosynthetic, nutritional, and productive efficiency of (Ficus carica L.) subjected to conduction systems in a semi-arid region of Brazil. Agriculture 15: 2128. doi: doi:10.3390/agriculture15202128
  69. Pacheco C. A., Oliveira A., Tomaz A. (2023). Effects of mineral and organic fertilization on forage maize yield, soil carbon balance, and NPK budgets, under rainfed conditions in the Azores Islands (Portugal). Int. J. Plant Prod. 17, 463 – 475. doi: doi:10.1007/s42106-023-00250-7
  70. Pu X. Z., Zhang G. J., Zhang P. P., Liu Y. J., Zhang W. F. (2016). Effects of straw management, inorganic fertiliser, and manure amendment on soil microbial properties, nutrient availability, and root growth in a drip-irrigated cotton field. Crop Pasture Sci. 67, 1297 – 1308. doi: doi:10.1071/CP16230
  71. Ramya M., Nideesh P., Binitha N. K. (2026). Ameliorating sandy loam soils: assessing soil nutrient dynamics and crop performance under variable rates of hydrogel, humic acid and biochar. Int. J. Plant Soil Sci. 38, 307 – 329. doi: doi:10.9734/ijpss/2026/v38i66120
  72. Ray R. L., Kularathna K. M., Griffin R. W., Abeysingha N., Woldesenbet S., Elhassan A.. (2025). Enhancing plant and soil health through organic amendments in a humid environment. Rhizosphere 35: 101126. doi: doi:10.1016/j.rhisph.2025.101126
  73. Rehman S., De Castro F., Aprile A., Benedetti M., Fanizzi F. P. (2023). Vermicompost: enhancing plant growth and combating abiotic and biotic stress. Agronomy 13: 1134. doi: doi:10.3390/agronomy13041134
  74. Sanchez E., Zabaleta R., Navas A. L., Torres-Sciancalepore R., Fouga G., Fabani M. P.. (2024). Assessment of pistachio shell-based biochar application in the sustainable amendment of soil and its performance in enhancing bell pepper (Capsicum annuum L.) growth. Sustainability 16: 4429. doi: doi:10.3390/su16114429
  75. Santos F. C., Albuquerque Filho M. R., Soares J. R., Jesmin T., Manirakiza N., Silveira M. C. T.. (2025). Organic matter: a critical soil health indicator in agrosystems within the Cerrado of Bahia, Brazil and South Florida, USA. Front. Soil Sci. 5: 1524550. doi: doi:10.3389/fsoil.2025.1524550
  76. Senesi N. (1989). Composted materials as organic fertilizers. Sci. Total Environ. 81-82, 521 – 542. doi:10.1016/0048-9697(89)90161-7
  77. Serri F., Souri M. K., Rezapanah M. (2021). Growth, biochemical quality and antioxidant capacity of coriander leaves under organic and inorganic fertilization programs. Chem. Biol. Technol. Agric. 8: 33. doi: doi:10.1186/s40538-021-00232-9
  78. Sestak Z., Catsky J., Jarvis P. G. (1971). Plant Photosynthetic Production: Manual of Methods. The Hague: Junk Publishers.
  79. Shaji H., Chandran V., Mathew L. (2021). “ Organic fertilizers as a route to controlled release of nutrients,” in Controlled Release Fertilizers for Sustainable Agriculture, eds. Lewu F. B., Volova T., Thomas S., Rakhimol K. R. (Cambridge: Academic Press), 231 – 245.
  80. Shevela D., Nonomura A. (2026). The essential nutrient elements in photosynthesis. Front. Photobiol. 4: 1817712. doi: doi:10.3389/fphbi.2026.1817712
  81. Singleton V. L., Rossi J. Á. (1965). Colorimetry of total phenolics with phosphomolybdic-phosphotungstic acid reagents. Am. J. Enol. Vitic. 16, 144 – 158. doi: doi:10.5344/ajev.1965.16.3.144
  82. Soares A. S., Miranda C., Teixeira C. A., Coutinho J., Trindade H., Coelho A. C. (2019). Impact of different treatments on Escherichia coli during storage of cattle slurry. J. Environ. Manag. 236, 323 – 327. doi:,. doi:10.1016/j.jenvman.2019.02.005
  83. Song W., Shu A., Liu J., Shi W., Li M., Zhang W.. (2022). Effects of long-term fertilization with different substitution ratios of organic fertilizer on paddy soil. Pedosphere 32, 637 – 648. doi: doi:10.1016/S1002-0160(21)60047-4
  84. Suhani I., de Araujo A. S. F., Kothari R., Vaish B., Singh R. P. (2025). Investigating the effect of compost and vermicompost on wheat plants and soil health under natural salt affected field conditions. Int. J. Environ. Res. 19: 42. doi: doi:10.1007/s41742-024-00710-6
  85. Sun-inthara T., Juntahum S., Senawong K., Katekaew S., Laloon K. (2024). Pelletization of soil amendment: optimizing the production and quality of soil amendment pellets from compost with water and biochar mixtures and their impact on soil properties. Environ. Technol. Innov. 33: 103505. doi: doi:10.1016/j.eti.2023.103505
  86. Suvendran S., Acevedo M. F., Smithers B., Walker S. J., Xu P. (2025). Soil fertility and plant growth enhancement through compost treatments under varied irrigation conditions. Agriculture 15: 734. doi: doi:10.3390/agriculture15070734
  87. Syarifinnur N. Y., Prasetya B., Handayanto E. (2020). Effectiveness of compost and vermicompost from market organic wasteto improve soil chemical properties. IOP Conf. Ser: Mater. Sci. Eng. 980, 012068. doi: doi:10.1088/1757-899X/980/1/01206
  88. Sylvestre T. B., Braos L. B., Filho F. B., Cruz M. C. P., Ferreira M. E. (2019). Mineral nitrogen fertilization effects on lettuce crop yield and nitrogen leaching. Sci. Hortic. 255, 153 – 160. doi: doi:10.1016/j.scienta.2019.05.032
  89. Tan Z. S., Manogaran M. D., Shamsuddin R., Hakimi M., Looi L. W., Woo K. T.. (2025). Comparative study on composting and vermicomposting to improve physicochemical properties of digestate with the addition of kitchen waste. Food Technol. Biotechnol. 63, 149 – 158. doi:,. doi:10.17113/ftb.63.02.25.8904
  90. Thamburaj S., Singh N. (2001). Textbook of Vegetables, Tubercrops and Spices. New Delhi: Indian Council of Agricultural Research.
  91. Theourn S., Pheap S., Lam B., Williams J., Ro S. (2021). Combination of vermicompost and mineral fertilizer on growth and yield of romaine lettuce (Lactuca sativa var. longifolia Lam). Asian J. Agric. Res. Extn. 1, 35 – 40.
  92. Tütüncü Ç. A., Saka A. K., Ay A., Özer M. O., Yılmaz H., Ozer H. (2025). Potential use of different organic fertilizers in lettuce cultivation. Compost. Sci. Util. 32, 94 – 103. doi: doi:10.1080/1065657X.2025.2498328
  93. Wahidurromdloni F., Budiastuti M. T. S., Supriyono S. (2025). Effectiveness of organic fertilizer on root performance and nutrient uptake of soybean in agroforestry system. J. Ecol. Eng. 26, 161 – 170. doi: doi:10.12911/22998993/199821
  94. Wang T., Yu L., Wang Z., Yang C., Dong F., Yang D.. (2025). Effect of simulated acidification on soil properties and plant nutrient uptake of eggplant in greenhouse. Front. Plant Sci. 16: 1558458. doi:,. doi:10.3389/fpls.2025.1558458
  95. Xu Y., Xu X., Li J., Guo X., Gong H., Ouyang Z.. (2023). Excessive synthetic fertilizers elevate greenhouse gas emissions of smallholder-scale staple grain production in China. J. Clean. Prod. 430: 139720. doi: doi:10.1016/j.jclepro.2023.139720
  96. Xu Q., Zhang T., Niu Y., Mukherjee S., Abou-Elwafa S. F., Nguyen N. S. H.. (2024). A comprehensive review on agricultural waste utilization through sustainable conversion techniques, with a focus on the additives effect on the fate of phosphorus and toxic elements during composting process. Sci. Total Environ. 942: 173567. doi:,. doi:10.1016/j.scitotenv.2024.173567
  97. Yang L., Wang M., Yu J., Li S., Hong L. (2025). Organic fertilizers promote accumulation of mineral nutrients in citrus leaves by affecting soil biochemical properties and bacteria. Plants 14: 2826. doi:,. doi:10.3390/plants14182826
  98. Yatoo A. M., Ali M. N., Baba Z. A., Hassan B. (2021). Sustainable management of diseases and pests in crops by vermicompost and vermicompost tea. a review. Agron. Sustain. Dev. 41: 7. doi: doi:10.1007/s13593-020-00657-w
  99. Yatoo A. M., Elrys A. S., Okoth N., Opande T., Meng L., Hamid B.. (2025). “ Compost and vermicompost: Eco-friendly farming practices to promote sustainable agriculture,” in Handbook of Agricultural Technologies, eds. Al-Khayri J. M., Yatoo A. M., Jain S. M., Penna S. (Singapore: Springer), 1 – 15.
  100. Zapałowska A., Jarecki W., Skwiercz A. T., Kunka M. (2025). The impact of using compost, vermicompost and mineral fertilization on soil nematode communities and maize grain quality in a pot experiment. Sustainability 17: 9936. doi: doi:10.3390/su17229936
  101. Zhao Y., Chen Y., Dai H., Cui J., Wang L., Sui P. (2021). Effects of organic amendments on the improvement of soil nutrients and crop yield in sandy soils during a 4-year field experiment in Huang-Huai-Hai Plain, Northern China. Agronomy 11: 157. doi: doi:10.3390/agronomy11010157
  102. Zucconi F., Forte M., Monaco A., Bertoldi M. (1981). Biological evaluation of compost maturity. Biocycle 22, 27 – 29.
  103. Zuzunaga-Rosas J., Calone R., Mircea D. M., Shakya R., Ibáñez-Asensio S., Boscaiu M.. (2024). Mitigation of salt stress in lettuce by a biostimulant that protects the root absorption zone and improves biochemical responses. Front. Plant Sci. 15: 1341714. doi:,. doi:10.3389/fpls.2024.1341714

Citation

Morais, M. C., et al. (2026). Agronomic performance and soil chemical properties following the application of pelletized compost and vermicompost derived from vineyard pruning residues and sewage sludge in lettuce production. Frontiers in Sustainable Food Systems, Volume 10. https://doi.org/
Received
Accepted
Published
Volume
10 - 2026

Copyright

Copyright © 2026 Morais, Nascimento-Gonçalves, Dinis, Pereira, Branco, Lopes, Azevedo, Medeiros, Coimbra, Claro, Marques, Sousa, Oliveira and Roboredo.

License: https://creativecommons.org/licenses/by/4.0/

*Correspondence: Maria C. Morais

Article metrics

Views
0
Downloads
0
Citations
0
Shares
0

Related articles

Original ResearchMaking inequities visible: a call for participatory food system dashboards for SDG monitoringRositsa T. Ilieva, Yvette Ng, Nevin CohenReviewAvocado (Persea americana Mill) seed starch: composition, extraction, and applications—a comprehensive reviewNehal Chavda, Rajdip Khaniya, Margi Gokalani, Ajay SinghBrief Research ReportComparison of food carbon footprints using 20- and 100-year timeframesKatie Osborn, Silas Crocker, Kira Presley, Alexis Shenkiryk, Maggie Spire, Jennifer Molidor, Mansha Kapur, Jennifer A. Jay