Enhancing the growth, yield and physiological response of two lettuce (Lactuca sativa L.) cultivars through NFT system optimization
Metadata
- Cite key: pastorarbuluEnhancingGrowthYield2025
- Item type: Journal Article
- Authors: P. Pastor-Arbulú, A. Rodríguez-Delfín
- Affiliation: Facultad de Ciencias, Centro de Investigación de Hidroponía y Nutrición Mineral, Universidad Nacional Agraria La Molina, Lima, Peru (both authors; second author also listed under the standalone Centro de Investigación de Hidroponía y Nutrición Mineral address)
- Journal: Frontiers in Plant Science 16 (2025) 1639002
- Date: 08/2025
- Date added: 2026-08-10
- DOI: 10.3389/fpls.2025.1639002
- Funding: Universidad Nacional Agraria La Molina (Vicerrectorado de Investigación), covering the Article Processing Charge (APC) only; no research-funding body stated
- URL: https://doi.org/10.3389/fpls.2025.1639002
- PDF:
Pastor-Arbulú and Rodríguez-Delfín - 2025 - Enhancing the growth, yield and physiological response of two lettuce (Lactuca sativa L.) cultivars.pdf
Opinion
This is a hydroponic-only paper with no aquaponic component whatsoever — no fish, no RAS, no fish-derived water anywhere in the methods. It sits in this vault as NFT-design/cultivar-optimization literature rather than as an aquaponics-vs-hydroponics comparison, and it is treated per CLAUDE.md/SCHEMA.md’s “papers missing half the schema” rule (the entire fish/aquaponic block is
NA, notNR). The experimental design itself is solid — a clean, properly randomized 2×3 factorial (cultivar × NFT module) with true replication (n=10/cell) and factorial ANOVA + Tukey’s HSD — and the narrative synthesis in the Discussion is unusually well-referenced against prior NFT/DFT lettuce literature from the same research group and others. The major weakness for data-extraction purposes: almost every biometric and physiological result (root/stem/leaf/head fresh and dry weight, plant height, total chlorophyll, SPAD, nitrate reductase activity) is reported only as a lettered bar chart, with no accompanying table and no numbers in the running text. Only three of the eighteen possible per-treatment result cells (six treatments × yield, plus everything else) carry an actual number in text: yield for Tropicana-Module-II (14.14 kg·m⁻²), Tropicana-Module-III (13.96 kg·m⁻²), and Starfighter-Module-II (13.45 kg·m⁻²). Per this vault’s “never read a value off a figure” rule, everything else isNRin trials.csv/plant.csv even though the paper clearly collected and analyzed it. The paper is worth citing for its qualitative findings (module × cultivar interaction, Tropicana’s shade-avoidance/elongation phenotype, the chlorophyll–nitrate-reductase correlation) but contributes very little to a quantitative synthesis dataset as currently written up.
Abstract
Introduction: In the context of increasing pressure on agricultural resources, hydroponic systems such as the nutrient film technique (NFT) are gaining prominence for their ability to optimize water use and space efficiency, and crop productivity in controlled environments. Lettuce (Lactuca sativa L.), a high-value leafy vegetable, is a key cash crop in controlled-environment agriculture. Light quality and intensity - critical drivers of plant physiology - require constant monitoring in soilless systems to ensure consistent performance. However, the interaction effects of NFT system design and cultivar selection on physiological behavior and yield stability remain underexplored.
Methods: This study evaluated the growth, yield, and physiological responses of two lettuce cultivars, Tropicana and Starfighter, cultivated in three NFT configurations: module I (8-channel) with a horizontal layout; and module II (13-channel) and module III (10-channel), both with pyramidal layouts. Although all the treatments were exposed to similar microenvironmental conditions, the photosynthetic photon flux density (PPFD) was monitored throughout the crop cycle to maintain light uniformity. Agronomic performance was evaluated through biometric parameters in roots, stems, leaves and heads, and the yield was calculated per unit area; while the physiological responses included measurements of relative and total chlorophyll content and nitrate reductase enzymatic activity.
Results and discussion: Tropicana generally outperformed Starfighter, particularly in modules II and III, which also supported higher pigment accumulation and improved nitrogen metabolism across both cultivars. The highest yields were achieved by Tropicana in modules II (14.14 kg·m⁻²) and III (13.96 kg·m⁻²), closely followed by Starfighter in module II (13.45 kg·m⁻²). These findings highlight how strategic integration of system configuration and cultivar selection can increase physiological efficiency, stabilize yields, and promote sustainability in hydroponic lettuce production.
Summary
The authors grew two curly, heat-tolerant lettuce cultivars (Tropicana and Starfighter) in a completely randomized 2×3 factorial design at the Universidad Nacional Agraria La Molina (Lima, Peru, summer 2021), crossing cultivar against three NFT hydroponic module designs: an 8-channel horizontal module (I) and two pyramidal modules with 13 (II) and 10 (III) channels, each replicated with 10 plants per treatment cell (60 plants total, harvested 48 days after germination / 25 days after final transplant into the NFT channels). All modules were fed from one shared 1,100 L nutrient-solution reservoir under a 50% shade mesh, so only module geometry and cultivar were varied as treatment factors. They measured root/stem/leaf/head fresh and dry biomass, plant height, root length, harvested yield per unit area, total and relative (SPAD) chlorophyll content, and nitrate reductase (NR) enzymatic activity, analyzed by factorial ANOVA and Tukey’s HSD. Significant module × cultivar interactions were found for stem biomass and yield; Tropicana generally outperformed Starfighter, especially in modules II and III, and module II produced the highest total chlorophyll and NR activity regardless of cultivar, which were themselves significantly correlated with each other (Pearson r=0.548, p<0.01). The headline numeric results are the yields for the three best-performing treatments — Tropicana-Module-II 14.14 kg/m², Tropicana-Module-III 13.96 kg/m², Starfighter-Module-II 13.45 kg/m² — which the authors argue substantially exceed prior DFT-based yield benchmarks from the same research group and validate NFT module geometry as a lever for productivity independent of nutrient concentration (held constant across all six treatments here). Root growth was unaffected by either factor, and the SPAD chlorophyll index did not differ significantly among treatments, which the authors attribute to SPAD’s lower sensitivity relative to solvent-extraction total chlorophyll assays.
Experiment data
- Location: Centro de Investigación de Hidroponía y Nutrición Mineral, Universidad Nacional Agraria La Molina, Lima, Peru (-12.07982, -76.94774), mesh house with 50% shade, summer 2021
- Design: Completely randomized design, 2×3 factorial (2 lettuce cultivars × 3 NFT module configurations = 6 treatments), 10 replications/treatment (60 plants total); Module I horizontal (8 channels), Module II pyramidal (13 channels), Module III pyramidal (10 channels), each channel 7.5 cm diameter × 3 m length (see Extraction notes for a channel-diameter conflict with a separate generic-description passage)
- Replicates / n: 10 plants per treatment cell
- Duration: 48 days after germination to harvest; 25 days specifically from final (channel) transplant to harvest
- Organisms: Lettuce (Lactuca sativa), cvs. Tropicana and Starfighter (curly type, heat-tolerant, Johnny’s Selected Seeds) — no aquaculture organism, hydroponic-only study
- Statistics: Factorial ANOVA + Tukey’s HSD (p<=0.05); Pearson correlation (total chlorophyll vs. nitrate reductase activity, r=0.548, p<0.01); Minitab 19 or Python
- Yield: Tropicana Module II 14.14 kg/m2 and Module III 13.96 kg/m2 (highest); Starfighter Module II 13.45 kg/m2; remaining three cells (both cultivars Module I, Starfighter Module III) reported only via Figure 2G bar chart, no numeric values in text
- Total chlorophyll content: Significantly higher in Module II regardless of cultivar (p<0.05); no numeric values given (figure only, Figure 4A)
- Nitrate reductase (NR) enzymatic activity: Significant effect of both module and cultivar (p<0.05); highest in Tropicana Module II; no numeric values given (figure only, Figure 4B)
Yield
This paper: Only three of the six treatment cells have a stated numeric yield: Tropicana in Module II (14.14 kg/m²) and Module III (13.96 kg/m²), and Starfighter in Module II (13.45 kg/m²) — all given in the Abstract. The remaining three cells (both cultivars in Module I, and Starfighter in Module III) are shown only in Figure 2G with Tukey letters and no numbers in text, so they are recorded NR per this vault’s never-read-a-figure rule. The Results narrative (3.2.1, p.4) states significant differences in yield “between the interaction of the module and the cultivar (p < 0.05)” and that “Module II and the Tropicana cultivar in module III presented an average yield that was statistically greater than that of the other combinations, especially with respect to the yield of module I.” The Discussion (p.7) separately states the study’s overall “maximums recorded in this study of 11.07 to 14.14 kg·m⁻²” when comparing against Rodríguez-Delfín et al. (2001)‘s DFT benchmark of 2.74–3.38 kg/m²; 14.14 matches the Tropicana-Module-II figure above, but 11.07 is never attributed to any one of the six specific treatment cells, so it could not be entered into any row.
Compared with:
- todo Rodríguez-Delfín et al. 2001 — Peruvian modified DFT system, up to 27 plants/m², yield maximums 2.74–3.38 kg/m², much lower than this paper’s 11.07–14.14 kg/m² range, cited as evidence of NFT’s greater efficiency over DFT for this genus/species combination (p.7)
- todo Rodríguez-Delfín et al. 2022 — modified NFT systems in “pandemic times,” highest average yield recorded in a 10-channel system (comparable to this paper’s Module III) for the ‘Ariana’ variety, partially consistent with this paper’s finding that Module III favors Tropicana; but no significant difference was found there between 8- and 13-channel systems, unlike here (p.7)
- todo Espinoza et al. 2019 — productive behavior of 11 lettuce varieties in a recirculating NFT system (Chachapoyas, Peru), cited for varietal influence on light-use/nutrient-assimilation efficiency in NFT, consistent direction with this paper’s cultivar effect (p.7)
- todo Góis et al. 2024 — lettuce performance in NFT improved significantly under precise EC/pH management, cited as the reason this paper controlled EC/pH uniformly across all modules (p.7)
Physiological responses: chlorophyll and nitrate reductase activity
This paper: Total chlorophyll content differed significantly among treatments (p<0.05), highest in Module II for both cultivars regardless of cultivar identity (Results 3.3, p.5); no numeric values are given anywhere in text, only Figure 4A. Nitrate reductase (NR) enzymatic activity was significantly affected by both module and cultivar (p<0.05), with Tropicana in Module II showing the highest rate of nitrate-to-nitrite reduction, and Starfighter in Module I showing a comparable rate to its own counterpart; again no numeric values are given, only Figure 4B. Total chlorophyll and NR activity were significantly correlated (Pearson r=0.548, p<0.01, Figure 5), which the authors interpret as evidence that Module II’s light/nutrient environment jointly favors pigment accumulation and nitrogen assimilation. In contrast, the SPAD index (a portable, non-destructive proxy for relative chlorophyll) did not differ significantly among treatments (p>0.3, Supplementary Figure S3) — the authors attribute this to SPAD’s comparatively lower sensitivity to subtle photosynthetic changes relative to solvent-extraction total chlorophyll assays, and to their own random (rather than fixed) leaf-sampling protocol relative to some cited comparators.
Compared with:
- todo Gupta 2020 — describes light activation of nitrate reductase (NR) as a key step in the nitrate-to-nitrite reduction pathway, cited as the mechanistic basis for the Module-II light-environment/NR-activity link found here (p.7)
- todo Malca Soto 2013 — nitrate reductase activity and hydroponic growth of lettuce cv. ‘Crufia’ under four nutrient solutions; cited alongside Pinto et al. (2014) for the general finding that higher nitrogen levels raise NR activity, though this paper argues its own module-driven differences are more about light-harvesting than nutrient concentration (held constant here) (p.7)
- todo Pinto et al. 2014 — nitrate reductase, glutamine synthetase and soil N-species content in lettuce; cited alongside Malca Soto 2013 for the nitrogen-NR relationship (p.7)
- todo Taha et al. 2024 — reports a strong correlation between total chlorophyll content and SPAD units in aquaponically grown lettuce using hyperspectral/RGB imaging, a result this paper’s own data does not corroborate (SPAD was ns here); the authors attribute the discrepancy partly to Taha et al.’s use of the exact same sampled leaves versus this paper’s random leaf sampling (p.7-8) — worth checking whether this citation, being aquaponics-specific, is already logged elsewhere in the vault
- todo Coronel et al. 2009 — nitrate reductase activity and chlorophyll content in lettuce grown hydroponically and organically, cited in support of linking high NR activity to lower nitrate-accumulation risk in edible tissue (p.7)
Growth, biomass and plant height (figure-only data)
This paper: Root fresh/dry weight and root length did not differ significantly between treatments (p>0.05, Supplementary Figure S2), indicating root development is independent of both cultivar and NFT module. Stem fresh and dry biomass differed significantly for module, cultivar, and their interaction (p<0.02); Modules II and III favored greater stem biomass, and Tropicana had greater stem development than Starfighter (Figure 2A-B). Leaf fresh weight showed no significant differences (p>0.05, Figure 2C), but leaf dry weight was significantly greater for Tropicana in Module III than Starfighter in Module I (p<0.05, Figure 2D). Head fresh and dry weight followed the same pattern as leaf dry weight — Tropicana-Module-III significantly exceeding Starfighter-Module-I, other combinations statistically similar (p<0.05, Figure 2E-F). Plant height differed significantly among treatments (p<0.05, Figure 3): Tropicana in Module III achieved the greatest elongation, Module II produced similar heights for both cultivars, and Module I produced the smallest plants overall. None of these variables have a single numeric value reported in text or a table anywhere in the paper — all are bar-chart-only with Tukey letters, so all are recorded NR in trials.csv/plant.csv per this vault’s figure-reading rule. The Discussion (p.7) separately claims Tropicana “comparatively increased these parameters by 80%,” framing Tropicana as shade-avoiding (elongating) versus Starfighter as shade-tolerant (more compact); the specific parameter and baseline for the 80% figure are not stated, so it could not be mapped to any cell.
Compared with:
- todo De M. N. Góis et al. 2024 — lettuce growth in different hydroponic systems and nutrient concentrations; cited for the finding that NFT performance improves under precise EC/pH management, and for the specific pattern of Tropicana-Module-III outperformance matching what this paper found (p.7)
- todo Valverde et al. 2009 — effect of light quality on nitrate reductase activity in NFT-grown lettuce; this paper’s own NFT protocol is explicitly configured following Valverde et al.’s method (Methods 2.2), and it is cited again in Discussion for varietal light/nutrient-use efficiency and for the 400-600 µmol·m⁻²·s⁻¹ optimal-PPFD range (p.3, p.7-8)
- todo Chamoli et al. 2024 — comparative analysis of hydroponically and soil-grown lettuce; cited (with Suharjo and Suaib 2022) for the claim that NFT structural design (gutter slope, substrate, module orientation) significantly affects light distribution and root oxygenation, offered as a mechanistic explanation for this paper’s module-driven growth differences (p.7)
- todo Suharjo and Suaib 2022 — growth analysis of NFT-grown lettuce; cited alongside Chamoli et al. 2024 for the same structural-design mechanism (p.7)
- todo Pennisi et al. 2020 — optimal light intensity for lettuce given as 250-300 µmol·m⁻²·s⁻¹, narrower/lower than the 400-600 µmol·m⁻²·s⁻¹ range this paper cites (via Valverde et al. 2009, Kusuma et al. 2021, Zhen et al. 2022) as optimizing photosynthesis without photoinhibition — an unreconciled disagreement in the literature that the Discussion notes but does not resolve (p.8)
Linked claims
- NFT module geometry (channel count, horizontal vs. pyramidal layout) significantly affects lettuce yield and stem biomass independent of nutrient concentration
- Cultivar selection interacts with NFT system design to determine lettuce growth and yield outcomes
- Total chlorophyll content and nitrate reductase activity are positively correlated in lettuce
- SPAD index is a less sensitive proxy for chlorophyll status than solvent-extraction total chlorophyll assays
Citations to chase
- todo Rodríguez-Delfín, A., Chang, M., and Hoyos, M. (2001). Lettuce production in a Peruvian modified DFT system. ISHS Hort. Min. 554, 273-278. doi:10.17660/ActaHortic.2001.554.28 — DFT yield benchmark (2.74-3.38 kg/m²) this paper compares against
- todo Rodríguez-Delfín, A., López, A., Rojas, V., and García, B. (2022). Yield of lettuce (Lactuca sativa) plants grown with modified NFT systems in pandemic times. Curr. Top. Agron. Sci. 2, 1-9 — this paper’s own Methods (module design, plant density citations) are drawn directly from this reference
- todo Espinoza, S.T.L., Peña, A.R., Valqui, N.C.V., and Chávez, J.C.N. (2019). Productive behavior of 11 varieties of lettuce (Lactuca sativa L.) in a recirculating NFT hydroponic system (Chachapoyas - Amazonas). J. Sustain Agroprod. Res. 2, 50
- todo Góis, H.M.d.M.N., De Ade Oliveira, F., Oliveira, R.R.T., Pinto, F.F.B., and Aroucha, E.M.M. et al. (2024). Lettuce growing in different hydroponic systems and nutrient concentrations of the nutrient solution. Rev. Bras. Eng. Agric. Ambient 28(8), e279686
- todo Gupta, K.J. (2020). Nitrogen Metabolism in Plants: Methods and Protocols. Methods in Molecular Biology, vol. 2057. Humana Press
- todo Taha, M.F., Mao, H., Wang, Y., ElManawy, A.I., Elmasry, G., and Wu, L. et al. (2024). High-throughput analysis of leaf chlorophyll content in aquaponically grown lettuce using hyperspectral reflectance and RGB images. Plants 13(3), 392 — aquaponics-specific; check vault for an existing note before adding a new one
- todo Valverde, K., Chang, M., and Rodríguez-Delfín, A. (2009). Effect of the light quality on the nitrate reductase activity in lettuce plants grown in NFT. Acta Hortic. 843, 89-96
- todo Vanacore, L., El-Nakhel, C., Modarelli, G.C., Rouphael, Y., Pannico, A., and Langellotti, A.L. et al. (2024). Growth, ecophysiological responses, and leaf mineral composition of lettuce and curly endive in hydroponic and aquaponic systems. Plants 13, 2852 — cited only in passing (sustainability discussion, p.8), not for specific comparable data, but directly aquaponics-relevant; a
modarelliHydroponicAquaponicFloating2023-adjacent reference already partially covered in this vault
Extraction notes
Hydroponic-only paper, no aquaponic component: This paper reports zero fish, RAS, or fish-derived water anywhere — it is a pure NFT hydroponic mineral-nutrient-solution study comparing module geometry and cultivar. Per SCHEMA.md’s “papers missing half the schema” rule (“a hydroponic-only or fish-only study gets NA across the block that does not apply”), the entire Fish/feed block and all AP-labelled columns (Aq pH, FUE AP, Tissue nitrate AP, AP) are recorded NA for all six trials, following the precedent already established in this vault by moncadaUsePlantGrowthpromoting2021 (also a pure hydroponic factorial study, AP=NA, yield recorded in HYD).
Trial-count judgment call (six rows, not three or two): The paper’s design is a genuine 2 (cultivar) × 3 (NFT module) factorial with n=10 replicate plants per cell and per-cell Tukey-lettered results (not marginal means pooled across either factor) — the Results text explicitly reports significant module × cultivar interaction effects for stem biomass (p<0.02) and yield (p<0.05). Pooling across cultivar (three module rows) or across module (two cultivar rows) would discard exactly the interaction the paper itself found significant, so this note records one trials.csv row per cultivar × module cell (six rows total, -T1 through -T6), each documenting TRIAL DEFINITION per SCHEMA.md. This differs from the marginal-means approach used in moncadaUsePlantGrowthpromoting2021 (which pooled across its second crossed factor); the difference is intentional and stated in each row’s remarks, because that paper’s crossed factor was not reported with a stated significant interaction at the cell level in the same way.
WARN-MATERIAL, channel/pipe diameter (Introduction p.2 vs. Methods 2.3 p.3): The Introduction’s general NFT description states “PVC pipes with a diameter of 110 mm served as growth channels.” Methods 2.3 states, once per module (three times, identical figure each time, for Modules I, II and III), that channels measure “7.5 cm in diameter” (=75 mm). 110 mm and 75 mm are ~1.47x apart, not a rounding difference, and both purport to describe the same physical growth channel. Recorded 7.5 cm/75 mm in each trial’s Media Details column (the module-specific, three-times-repeated figure), with 110 mm preserved as the other candidate. No dedicated trials.csv column exists for a single pipe-diameter value beyond Media Details, so this does not propagate further.
WARN-MINOR, total cultivation duration (Methods 2.2 vs. Results 3.1, p.3-4): Methods 2.2 describes 8 days from sowing to first transplant, then “12 days later” (day 20) transplant into NFT channels, then “For 25 days, the plants were nourished daily via the… NFT system” (implying harvest at day 45). Results 3.1 instead states plants were “sampled 48 days after germination.” 20+25=45, not 48 (a 3-day gap). The “25 days” figure is independently corroborated by Results 3.1’s own restatement (“almost ready for harvesting after 25 days of mineral solution supply and recirculation”), so Days Plant after transplant = 25 was recorded directly (not derived from 48 minus 20); this does not affect any other cell, since no column captures total germination-to-harvest time.
NOT DERIVED, left NR: Plants/m2 — Methods 2.3 (p.3) states “120, 190 and 150 lettuce plants are harvested in modules I, II and III, respectively” over a stated 4.5 m² per module (citing Rodríguez-Delfín et al. 2022), but this reads as the modules’ general production-capacity figures from that citation rather than this specific 60-day/60-plant experiment, and dividing count by area either way would be derivation. Water recycle (L/min) — only pump wattage (372.85 W) is given, not a flow rate; converting one to the other would be derivation.
[not reported] fields, grouped, across all six trials:
- Water/system: Water recycle (L/min), Water classification, Daily Water exchange rate, pHOptimal, FUE HYD, WUE, Dissolved Oxygen, EC, Water temperature, TAN/NH4-N, NO2-N, NO3-N, Air supplement, Iron supplemented, Remineralization, pH Buffers, Artificial Lighting, Climate control (a passive 50% shade mesh is described, but the paper never explicitly states the presence/absence of active heating/cooling/humidity control, so this is recorded
NRwith the shade-mesh detail noted rather than inferred asN) — none of these water-chemistry or infrastructure details are given anywhere in the extracted text; the paper’s water-quality instrumentation/monitoring, if any, is not described. - Plant biometrics: Plant Category, Plants/m2, SPAD (aquaponics), Plant height, Leaf count (not measured at all — not among this paper’s stated agronomic variables, which are root length, plant height, and fresh/dry weight of roots/stems/leaves/heads), Plant fresh weight, Plant dry matter — all figure-only (Figures 2, 3, Supplementary Figures S2-S3) with no numeric values in text or a table.
- Yield:
HYDcells for three of the six trials (both cultivars in Module I, Starfighter in Module III) — figure-only (Figure 2G). - Tissue nitrate AP/HYD: this paper measures nitrate reductase enzymatic activity (an enzyme assay reflecting nitrogen metabolism), not tissue nitrate concentration; these are different measurements, and tissue nitrate itself was never assessed.
plant_measurements.csv scope: Only two analytes fit the four defined categories (biochemistry/mineral/microbiology/proximate) at all: total chlorophyll content and the SPAD index (both biochemistry). Both are reported only as bar charts (Figure 4A; Supplementary Figure S3) with no numeric values anywhere in text or a table, so both are recorded as NR rows (one per trial, 12 rows total) per SCHEMA.md’s explicit instruction that figure-only values get an NR row with the reason in Notes, rather than being omitted. Nitrate reductase (NR) enzymatic activity does not fit any of the four plant_measurements.csv categories (it is an enzyme-activity assay, not a pigment/mineral/microbial/proximate measurement) and has no CSV home under the current schema — flagged here rather than force-fit, per SCHEMA.md’s instruction. No water-quality panel exists in this paper to route anywhere (no water chemistry table is reported at all).
Region/tags judgment call: Tagged Meta/Region/South-America (Peru, matching the spelling already used in alcarrazQualityLettuceLactuca2018, barbosaPerformanceNileTilapia2020, dasilvaProductionTambaquiJuveniles2025, and others). No Meta/Fish/ tag applied — there is no aquaculture organism in this paper at all, not even one mentioned in passing. Meta/Plant/Lettuce reused (existing leaf, not split further for the two named cultivars).
New wikilink targets introduced: P. Pastor-Arbulú, A. Rodríguez-Delfín (no existing author notes found in the vault). Reused Lettuce (Lactuca sativa) exactly as spelled in alcarrazQualityLettuceLactuca2018 and other existing notes.
PDF quality: Clean text layer throughout (11 pages including references and appendix), fully extractable via pdfplumber, no OCR issues. All core quantitative results (Figures 2-5) are genuinely chart-only in the source PDF (not a text-extraction artifact) — the paper simply does not tabulate its own biometric/physiological data anywhere outside the figures.
Source: Pastor-Arbulú and Rodríguez-Delfín - 2025 - Enhancing the growth, yield and physiological response of two lettuce (Lactuca sativa L.) cultivars.pdf
Data Tables
Structured data extracted from this paper into the vault's
trials.csv/plant_measurements.csvdatasets. Fields the paper didn't report are omitted. Download the full datasets (measurements).
Trial Parameters
pastorarbuluEnhancingGrowthYield2025-T1
Water
| Field | Value |
|---|---|
| Water volume in the system | 1,100 L (single shared nutrient-solution reservoir feeding all three NFT modules together via one 372.85 W recirculation pump; not partitioned per module, cultivar, or treatment, Methods 2.2, p.3) |
| Water type | La Molina hydroponic nutrient solution (Valderrama et al., 2020, cited); mineral nutrient solution, not fish-derived (Methods 2.2, p.3) |
Plant
| Field | Value |
|---|---|
| Plant | Lettuce (Lactuca sativa L.), cv. Tropicana |
| Details | Curly-type, heat-tolerant cultivar (Johnny’s Selected Seeds, Winslow, ME, USA); sown in quarry-sand substrate (0.5-1.00 mm) for germination/screening; transplanted to 4 cm pots at day 8; transplanted into NFT Module I channels 12 days later (day 20); harvested 48 days after germination / 25 days after channel transplant (Methods 2.2-2.3, p.3) |
| Days Plant after transplant | 25 |
| Tissue nitrate HYD | NR (this paper measures nitrate REDUCTASE ENZYMATIC ACTIVITY in leaf tissue, not tissue nitrate concentration - a different assay; see plant.csv/note) |
System & Setup
| Field | Value |
|---|---|
| System type | Horizontal-layout NFT system (Module I), 8 channels, 7.5 cm diameter x 3 m length, within a 1.5 m-wide structure (Methods 2.3, p.3) |
| Media Details | No growth media used - NFT roots are submerged directly in a thin (<=3 mm) recirculating nutrient film, no substrate (Introduction, p.2). Channel/pipe diameter stated as 7.5 cm (75 mm) for this module in the module-specific description (Methods 2.3, p.3), but a separate, earlier general-NFT-description passage (Introduction, p.2) states ‘PVC pipes with a diameter of 110 mm served as growth channels’ for the system overall. See Experimental Remarks, WARN-MATERIAL, for the conflict; 7.5 cm/75 mm used here as it is the module-specific, thrice-independently-repeated figure. |
| Nutrient supplemented | Y (All treatments fed via recirculating La Molina hydroponic mineral nutrient solution (Valderrama et al., 2020); solution formulation held constant across modules/cultivars - only NFT module design and cultivar were varied as treatment factors (Methods 2.2, p.3)) |
| Equipment | SPAD 502-Plus portable chlorophyll meter; Quantum Light Meter (PPFD monitoring); 372.85 W electric recirculation pump; temperature-controlled oven (70 degC, 48 h, biomass drying); spectrophotometer for total chlorophyll (Lichtenthaler and Wellburn, 1983; Wellburn, 1994 methods, with modifications); nitrate reductase activity assay per Neyra and Hageman (1974) (Methods 2.5, p.3) |
| Control Parameters | 50% shade mesh; NFT solution film height max 3 mm; single shared 1,100 L reservoir + 372.85 W pump feeding both pyramidal and horizontal modules; channel slope 1-5% (Introduction p.2, Methods 2.1-2.2) |
| Combination | Lettuce (Lactuca sativa L.) cvs. Tropicana and Starfighter grown in a 2x3 factorial (cultivar x NFT module design) completely randomized design; this row = Module I x Tropicana |
Site
| Field | Value |
|---|---|
| Region | South America |
| Country | Peru |
| Lat | -12.07982 |
| Long | -76.94774 |
| Average room Temperature | 25.82 degC day / 20.43 degC night, average; max 31.5 degC, min 15.6 degC during the trial; 66.4% relative humidity; 50% shade mesh used to reduce radiation/heat load (Methods 2.1, p.3, Supplementary Table S1) |
Results & Statistics
| Field | Value |
|---|---|
| Measured Unit | kg.m-2 (yield, only cells with a stated number); g/plant and cm (fresh/dry weight by organ, plant height, root length - all figure-only, no unit-bearing numeric values extracted); SPAD units and total-chlorophyll/NR-activity units not given in text (figure-only); umol.m-2.s-1 (PPFD) |
| Statistic Details | Factorial ANOVA (2 cultivars x 3 NFT modules) + Tukey’s HSD (p<0.05) after verifying normality and homogeneity of variance; Pearson correlation between total chlorophyll and nitrate reductase (NR) activity, r=0.548, p<0.01 (Figure 5); Minitab 19 or Python (Methods 2.7, p.3) |
| Statistically analysed | Y |
| Replicates (n) | 10 |
Experimental Remarks: TRIAL DEFINITION: this row = NFT Module I (Horizontal layout, 8 channels) x cultivar ‘Tropicana’, one cell of the paper’s 2 (cultivar) x 3 (module) completely randomized factorial design (Methods 2.3, p.3), n=10 replicate plants per treatment cell (60 plants total sampled 48 days after germination). No hydroponic control distinct from this design exists - all six cells ARE the trial; there is no separate baseline treatment, so HYD columns carry this cell’s own value and AP columns are NA throughout (no aquaponic arm anywhere in this paper - see Extraction notes in the note file for the trial-count judgment call, six rows one per cultivar x module combination, rather than three module-pooled rows or two cultivar-pooled rows, because the paper reports significant module x cultivar interaction effects, p<0.02-0.05, on stem biomass and yield, so pooling across either factor would discard the interaction the paper itself found significant). Paired ‘Starfighter’ cultivar in the same module is recorded as a separate sibling trial row. | WARN-MATERIAL channel/pipe diameter: Introduction (p.2) states generically ‘PVC pipes with a diameter of 110 mm served as growth channels’ for the NFT system description; Methods 2.3 (p.3) states, once per module (three times total, identical figure each time), that channels measure ‘7.5 cm in diameter’ (Module I, II and III alike). 110 mm and 75 mm are not a rounding difference (~1.47x apart) and describe what reads as the same physical growth channel. Recorded 7.5 cm/75 mm in Media Details (the module-specific, three-times-repeated figure, versus the single generic-description sentence); 110 mm preserved here as the other candidate. Affects: Media Details only; no dedicated schema column exists for a single pipe-diameter value that this would otherwise change. | WARN-MINOR total cultivation duration: Methods 2.2 states seedlings were transplanted into channels ‘12 days later’ than the first (day-8) transplant (day 20), then ‘For 25 days, the plants were nourished daily via the hydroponic nutrient film technique (NFT) system’ (day 20 to day 45); Results 3.1 (p.4) instead states plants were harvested ‘48 days after germination’. 20+25=45, not 48 - a 3-day gap. Both the Methods ‘25 days’ figure and the Results 3.1 restatement (‘almost ready for harvesting after 25 days of mineral solution supply and recirculation’, p.4) agree with each other and directly state the from-transplant duration, so 25 was recorded in Days Plant after transplant (not derived from 48-20); the 48-day germination-to-harvest total does not have its own dedicated column and does not conflict with the transplant-to-harvest figure used here, so no cell is affected beyond this note. | NOT DERIVED, left NR: Plants/m2 (Methods 2.3, p.3, states ‘120, 190 and 150 lettuce plants are harvested in modules I, II and III, respectively’ over a stated 4.5 m2 per module, citing Rodriguez-Delfin et al. 2022 - these totals describe the modules’ general production capacity per that citation, not necessarily this study’s own 60-day/60-plant experimental harvest; dividing count by area for either reading would be derivation, so left NR here with both raw inputs given); Water recycle (L/min not stated, only pump wattage 372.85 W, Methods 2.2, p.3 - converting wattage to a flow rate would be derivation). | Yield for this specific treatment cell: NR. Three of the six treatment cells (Module I both cultivars, Module III Starfighter) have no yield number in text - only Figure 2G bar chart with Tukey letters, no values given in running text or a table - so their AP/HYD yield cells are NR per the never-read-a-figure rule (SCHEMA.md). Discussion (p.7) separately states the study’s overall ‘maximums recorded… of 11.07 to 14.14 kg.m-2’; 14.14 matches the Tropicana-Module-II value above, but 11.07 is not attributed to any specific one of the six cells anywhere in the paper, so it is not entered in any row’s yield cell. | NO COLUMN / figure-only agronomic data (this paper reports almost all of its biometric and physiological data ONLY as Tukey-lettered bar charts, with no accompanying table and only three numeric yield values anywhere in running text - see plant.csv and the note’s Extraction notes for the full inventory): root length and root fresh/dry weight (ns, p>0.05, Supplementary Figure S2); stem fresh/dry weight (significant for module, cultivar and interaction, p<0.02, Figure 2A-B - modules II/III favor greater stem biomass, Tropicana > Starfighter); leaf fresh weight (ns, p>0.05, Figure 2C); leaf dry weight (Tropicana Module III significantly greater than Starfighter Module I, p<0.05, Figure 2D); head fresh/dry weight (Tropicana Module III significantly greater than Starfighter Module I, other combinations similar, p<0.05, Figure 2E-F); plant height (significant among treatments, p<0.05, Figure 3 - Tropicana Module III tallest, Module I smallest); total chlorophyll content (significant, p<0.05, Figure 4A - Module II highest regardless of cultivar); nitrate reductase (NR) enzymatic activity (significant for both factors, p<0.05, Figure 4B - Tropicana Module II highest); SPAD index (ns, p>0.3, Supplementary Figure S3). PPFD/PAR microclimate monitoring data (Appendix A, Supplementary Figure S4: NASA POWER-derived 21.47 MJ.m-2.day-1 global radiation / 9.87 MJ.m-2.day-1 PAR; in-mesh PPFD by module: Module I 558, Module II 580.76, Module III 558.82 umol.m-2.s-1, versus open-air control 943.67 umol.m-2.s-1 at noon). Relative stem-elongation claim (Discussion p.7: ‘Tropicana comparatively increased these parameters by 80%’) - basis/denominator for the 80% figure is not stated (which parameter, relative to which comparator), so not mapped to any cell.
pastorarbuluEnhancingGrowthYield2025-T2
Water
| Field | Value |
|---|---|
| Water volume in the system | 1,100 L (single shared nutrient-solution reservoir feeding all three NFT modules together via one 372.85 W recirculation pump; not partitioned per module, cultivar, or treatment, Methods 2.2, p.3) |
| Water type | La Molina hydroponic nutrient solution (Valderrama et al., 2020, cited); mineral nutrient solution, not fish-derived (Methods 2.2, p.3) |
Plant
| Field | Value |
|---|---|
| Plant | Lettuce (Lactuca sativa L.), cv. Starfighter |
| Details | Curly-type, heat-tolerant cultivar (Johnny’s Selected Seeds, Winslow, ME, USA); sown in quarry-sand substrate (0.5-1.00 mm) for germination/screening; transplanted to 4 cm pots at day 8; transplanted into NFT Module I channels 12 days later (day 20); harvested 48 days after germination / 25 days after channel transplant (Methods 2.2-2.3, p.3) |
| Days Plant after transplant | 25 |
| Tissue nitrate HYD | NR (this paper measures nitrate REDUCTASE ENZYMATIC ACTIVITY in leaf tissue, not tissue nitrate concentration - a different assay; see plant.csv/note) |
System & Setup
| Field | Value |
|---|---|
| System type | Horizontal-layout NFT system (Module I), 8 channels, 7.5 cm diameter x 3 m length, within a 1.5 m-wide structure (Methods 2.3, p.3) |
| Media Details | No growth media used - NFT roots are submerged directly in a thin (<=3 mm) recirculating nutrient film, no substrate (Introduction, p.2). Channel/pipe diameter stated as 7.5 cm (75 mm) for this module in the module-specific description (Methods 2.3, p.3), but a separate, earlier general-NFT-description passage (Introduction, p.2) states ‘PVC pipes with a diameter of 110 mm served as growth channels’ for the system overall. See Experimental Remarks, WARN-MATERIAL, for the conflict; 7.5 cm/75 mm used here as it is the module-specific, thrice-independently-repeated figure. |
| Nutrient supplemented | Y (All treatments fed via recirculating La Molina hydroponic mineral nutrient solution (Valderrama et al., 2020); solution formulation held constant across modules/cultivars - only NFT module design and cultivar were varied as treatment factors (Methods 2.2, p.3)) |
| Equipment | SPAD 502-Plus portable chlorophyll meter; Quantum Light Meter (PPFD monitoring); 372.85 W electric recirculation pump; temperature-controlled oven (70 degC, 48 h, biomass drying); spectrophotometer for total chlorophyll (Lichtenthaler and Wellburn, 1983; Wellburn, 1994 methods, with modifications); nitrate reductase activity assay per Neyra and Hageman (1974) (Methods 2.5, p.3) |
| Control Parameters | 50% shade mesh; NFT solution film height max 3 mm; single shared 1,100 L reservoir + 372.85 W pump feeding both pyramidal and horizontal modules; channel slope 1-5% (Introduction p.2, Methods 2.1-2.2) |
| Combination | Lettuce (Lactuca sativa L.) cvs. Tropicana and Starfighter grown in a 2x3 factorial (cultivar x NFT module design) completely randomized design; this row = Module I x Starfighter |
Site
| Field | Value |
|---|---|
| Region | South America |
| Country | Peru |
| Lat | -12.07982 |
| Long | -76.94774 |
| Average room Temperature | 25.82 degC day / 20.43 degC night, average; max 31.5 degC, min 15.6 degC during the trial; 66.4% relative humidity; 50% shade mesh used to reduce radiation/heat load (Methods 2.1, p.3, Supplementary Table S1) |
Results & Statistics
| Field | Value |
|---|---|
| Measured Unit | kg.m-2 (yield, only cells with a stated number); g/plant and cm (fresh/dry weight by organ, plant height, root length - all figure-only, no unit-bearing numeric values extracted); SPAD units and total-chlorophyll/NR-activity units not given in text (figure-only); umol.m-2.s-1 (PPFD) |
| Statistic Details | Factorial ANOVA (2 cultivars x 3 NFT modules) + Tukey’s HSD (p<0.05) after verifying normality and homogeneity of variance; Pearson correlation between total chlorophyll and nitrate reductase (NR) activity, r=0.548, p<0.01 (Figure 5); Minitab 19 or Python (Methods 2.7, p.3) |
| Statistically analysed | Y |
| Replicates (n) | 10 |
Experimental Remarks: TRIAL DEFINITION: this row = NFT Module I (Horizontal layout, 8 channels) x cultivar ‘Starfighter’, one cell of the paper’s 2 (cultivar) x 3 (module) completely randomized factorial design (Methods 2.3, p.3), n=10 replicate plants per treatment cell (60 plants total sampled 48 days after germination). No hydroponic control distinct from this design exists - all six cells ARE the trial; there is no separate baseline treatment, so HYD columns carry this cell’s own value and AP columns are NA throughout (no aquaponic arm anywhere in this paper - see Extraction notes in the note file for the trial-count judgment call, six rows one per cultivar x module combination, rather than three module-pooled rows or two cultivar-pooled rows, because the paper reports significant module x cultivar interaction effects, p<0.02-0.05, on stem biomass and yield, so pooling across either factor would discard the interaction the paper itself found significant). Paired ‘Tropicana’ cultivar in the same module is recorded as a separate sibling trial row. | WARN-MATERIAL channel/pipe diameter: Introduction (p.2) states generically ‘PVC pipes with a diameter of 110 mm served as growth channels’ for the NFT system description; Methods 2.3 (p.3) states, once per module (three times total, identical figure each time), that channels measure ‘7.5 cm in diameter’ (Module I, II and III alike). 110 mm and 75 mm are not a rounding difference (~1.47x apart) and describe what reads as the same physical growth channel. Recorded 7.5 cm/75 mm in Media Details (the module-specific, three-times-repeated figure, versus the single generic-description sentence); 110 mm preserved here as the other candidate. Affects: Media Details only; no dedicated schema column exists for a single pipe-diameter value that this would otherwise change. | WARN-MINOR total cultivation duration: Methods 2.2 states seedlings were transplanted into channels ‘12 days later’ than the first (day-8) transplant (day 20), then ‘For 25 days, the plants were nourished daily via the hydroponic nutrient film technique (NFT) system’ (day 20 to day 45); Results 3.1 (p.4) instead states plants were harvested ‘48 days after germination’. 20+25=45, not 48 - a 3-day gap. Both the Methods ‘25 days’ figure and the Results 3.1 restatement (‘almost ready for harvesting after 25 days of mineral solution supply and recirculation’, p.4) agree with each other and directly state the from-transplant duration, so 25 was recorded in Days Plant after transplant (not derived from 48-20); the 48-day germination-to-harvest total does not have its own dedicated column and does not conflict with the transplant-to-harvest figure used here, so no cell is affected beyond this note. | NOT DERIVED, left NR: Plants/m2 (Methods 2.3, p.3, states ‘120, 190 and 150 lettuce plants are harvested in modules I, II and III, respectively’ over a stated 4.5 m2 per module, citing Rodriguez-Delfin et al. 2022 - these totals describe the modules’ general production capacity per that citation, not necessarily this study’s own 60-day/60-plant experimental harvest; dividing count by area for either reading would be derivation, so left NR here with both raw inputs given); Water recycle (L/min not stated, only pump wattage 372.85 W, Methods 2.2, p.3 - converting wattage to a flow rate would be derivation). | Yield for this specific treatment cell: NR. Three of the six treatment cells (Module I both cultivars, Module III Starfighter) have no yield number in text - only Figure 2G bar chart with Tukey letters, no values given in running text or a table - so their AP/HYD yield cells are NR per the never-read-a-figure rule (SCHEMA.md). Discussion (p.7) separately states the study’s overall ‘maximums recorded… of 11.07 to 14.14 kg.m-2’; 14.14 matches the Tropicana-Module-II value above, but 11.07 is not attributed to any specific one of the six cells anywhere in the paper, so it is not entered in any row’s yield cell. | NO COLUMN / figure-only agronomic data (this paper reports almost all of its biometric and physiological data ONLY as Tukey-lettered bar charts, with no accompanying table and only three numeric yield values anywhere in running text - see plant.csv and the note’s Extraction notes for the full inventory): root length and root fresh/dry weight (ns, p>0.05, Supplementary Figure S2); stem fresh/dry weight (significant for module, cultivar and interaction, p<0.02, Figure 2A-B - modules II/III favor greater stem biomass, Tropicana > Starfighter); leaf fresh weight (ns, p>0.05, Figure 2C); leaf dry weight (Tropicana Module III significantly greater than Starfighter Module I, p<0.05, Figure 2D); head fresh/dry weight (Tropicana Module III significantly greater than Starfighter Module I, other combinations similar, p<0.05, Figure 2E-F); plant height (significant among treatments, p<0.05, Figure 3 - Tropicana Module III tallest, Module I smallest); total chlorophyll content (significant, p<0.05, Figure 4A - Module II highest regardless of cultivar); nitrate reductase (NR) enzymatic activity (significant for both factors, p<0.05, Figure 4B - Tropicana Module II highest); SPAD index (ns, p>0.3, Supplementary Figure S3). PPFD/PAR microclimate monitoring data (Appendix A, Supplementary Figure S4: NASA POWER-derived 21.47 MJ.m-2.day-1 global radiation / 9.87 MJ.m-2.day-1 PAR; in-mesh PPFD by module: Module I 558, Module II 580.76, Module III 558.82 umol.m-2.s-1, versus open-air control 943.67 umol.m-2.s-1 at noon). Relative stem-elongation claim (Discussion p.7: ‘Tropicana comparatively increased these parameters by 80%’) - basis/denominator for the 80% figure is not stated (which parameter, relative to which comparator), so not mapped to any cell.
pastorarbuluEnhancingGrowthYield2025-T3
Water
| Field | Value |
|---|---|
| Water volume in the system | 1,100 L (single shared nutrient-solution reservoir feeding all three NFT modules together via one 372.85 W recirculation pump; not partitioned per module, cultivar, or treatment, Methods 2.2, p.3) |
| Water type | La Molina hydroponic nutrient solution (Valderrama et al., 2020, cited); mineral nutrient solution, not fish-derived (Methods 2.2, p.3) |
Plant
| Field | Value |
|---|---|
| Plant | Lettuce (Lactuca sativa L.), cv. Tropicana |
| Details | Curly-type, heat-tolerant cultivar (Johnny’s Selected Seeds, Winslow, ME, USA); sown in quarry-sand substrate (0.5-1.00 mm) for germination/screening; transplanted to 4 cm pots at day 8; transplanted into NFT Module II channels 12 days later (day 20); harvested 48 days after germination / 25 days after channel transplant (Methods 2.2-2.3, p.3) |
| Days Plant after transplant | 25 |
| Tissue nitrate HYD | NR (this paper measures nitrate REDUCTASE ENZYMATIC ACTIVITY in leaf tissue, not tissue nitrate concentration - a different assay; see plant.csv/note) |
System & Setup
| Field | Value |
|---|---|
| System type | Pyramidal-layout NFT system (Module II), 13 channels, 7.5 cm diameter x 3 m length, within a 1.5 m-wide framework (Methods 2.3, p.3) |
| Media Details | No growth media used - NFT roots are submerged directly in a thin (<=3 mm) recirculating nutrient film, no substrate (Introduction, p.2). Channel/pipe diameter stated as 7.5 cm (75 mm) for this module in the module-specific description (Methods 2.3, p.3), but a separate, earlier general-NFT-description passage (Introduction, p.2) states ‘PVC pipes with a diameter of 110 mm served as growth channels’ for the system overall. See Experimental Remarks, WARN-MATERIAL, for the conflict; 7.5 cm/75 mm used here as it is the module-specific, thrice-independently-repeated figure. |
| Nutrient supplemented | Y (All treatments fed via recirculating La Molina hydroponic mineral nutrient solution (Valderrama et al., 2020); solution formulation held constant across modules/cultivars - only NFT module design and cultivar were varied as treatment factors (Methods 2.2, p.3)) |
| Equipment | SPAD 502-Plus portable chlorophyll meter; Quantum Light Meter (PPFD monitoring); 372.85 W electric recirculation pump; temperature-controlled oven (70 degC, 48 h, biomass drying); spectrophotometer for total chlorophyll (Lichtenthaler and Wellburn, 1983; Wellburn, 1994 methods, with modifications); nitrate reductase activity assay per Neyra and Hageman (1974) (Methods 2.5, p.3) |
| Control Parameters | 50% shade mesh; NFT solution film height max 3 mm; single shared 1,100 L reservoir + 372.85 W pump feeding both pyramidal and horizontal modules; channel slope 1-5% (Introduction p.2, Methods 2.1-2.2) |
| Combination | Lettuce (Lactuca sativa L.) cvs. Tropicana and Starfighter grown in a 2x3 factorial (cultivar x NFT module design) completely randomized design; this row = Module II x Tropicana |
Site
| Field | Value |
|---|---|
| Region | South America |
| Country | Peru |
| Lat | -12.07982 |
| Long | -76.94774 |
| Average room Temperature | 25.82 degC day / 20.43 degC night, average; max 31.5 degC, min 15.6 degC during the trial; 66.4% relative humidity; 50% shade mesh used to reduce radiation/heat load (Methods 2.1, p.3, Supplementary Table S1) |
Results & Statistics
| Field | Value |
|---|---|
| Measured Unit | kg.m-2 (yield, only cells with a stated number); g/plant and cm (fresh/dry weight by organ, plant height, root length - all figure-only, no unit-bearing numeric values extracted); SPAD units and total-chlorophyll/NR-activity units not given in text (figure-only); umol.m-2.s-1 (PPFD) |
| Statistic Details | Factorial ANOVA (2 cultivars x 3 NFT modules) + Tukey’s HSD (p<0.05) after verifying normality and homogeneity of variance; Pearson correlation between total chlorophyll and nitrate reductase (NR) activity, r=0.548, p<0.01 (Figure 5); Minitab 19 or Python (Methods 2.7, p.3) |
| Statistically analysed | Y |
| Replicates (n) | 10 |
| HYD | 14.14 kg/m2 |
Experimental Remarks: TRIAL DEFINITION: this row = NFT Module II (Pyramidal layout, 13 channels) x cultivar ‘Tropicana’, one cell of the paper’s 2 (cultivar) x 3 (module) completely randomized factorial design (Methods 2.3, p.3), n=10 replicate plants per treatment cell (60 plants total sampled 48 days after germination). No hydroponic control distinct from this design exists - all six cells ARE the trial; there is no separate baseline treatment, so HYD columns carry this cell’s own value and AP columns are NA throughout (no aquaponic arm anywhere in this paper - see Extraction notes in the note file for the trial-count judgment call, six rows one per cultivar x module combination, rather than three module-pooled rows or two cultivar-pooled rows, because the paper reports significant module x cultivar interaction effects, p<0.02-0.05, on stem biomass and yield, so pooling across either factor would discard the interaction the paper itself found significant). Paired ‘Starfighter’ cultivar in the same module is recorded as a separate sibling trial row. | WARN-MATERIAL channel/pipe diameter: Introduction (p.2) states generically ‘PVC pipes with a diameter of 110 mm served as growth channels’ for the NFT system description; Methods 2.3 (p.3) states, once per module (three times total, identical figure each time), that channels measure ‘7.5 cm in diameter’ (Module I, II and III alike). 110 mm and 75 mm are not a rounding difference (~1.47x apart) and describe what reads as the same physical growth channel. Recorded 7.5 cm/75 mm in Media Details (the module-specific, three-times-repeated figure, versus the single generic-description sentence); 110 mm preserved here as the other candidate. Affects: Media Details only; no dedicated schema column exists for a single pipe-diameter value that this would otherwise change. | WARN-MINOR total cultivation duration: Methods 2.2 states seedlings were transplanted into channels ‘12 days later’ than the first (day-8) transplant (day 20), then ‘For 25 days, the plants were nourished daily via the hydroponic nutrient film technique (NFT) system’ (day 20 to day 45); Results 3.1 (p.4) instead states plants were harvested ‘48 days after germination’. 20+25=45, not 48 - a 3-day gap. Both the Methods ‘25 days’ figure and the Results 3.1 restatement (‘almost ready for harvesting after 25 days of mineral solution supply and recirculation’, p.4) agree with each other and directly state the from-transplant duration, so 25 was recorded in Days Plant after transplant (not derived from 48-20); the 48-day germination-to-harvest total does not have its own dedicated column and does not conflict with the transplant-to-harvest figure used here, so no cell is affected beyond this note. | NOT DERIVED, left NR: Plants/m2 (Methods 2.3, p.3, states ‘120, 190 and 150 lettuce plants are harvested in modules I, II and III, respectively’ over a stated 4.5 m2 per module, citing Rodriguez-Delfin et al. 2022 - these totals describe the modules’ general production capacity per that citation, not necessarily this study’s own 60-day/60-plant experimental harvest; dividing count by area for either reading would be derivation, so left NR here with both raw inputs given); Water recycle (L/min not stated, only pump wattage 372.85 W, Methods 2.2, p.3 - converting wattage to a flow rate would be derivation). | Yield for this specific treatment cell: 14.14 kg/m2 (Abstract; Discussion p.7 gives the same figure as the upper end of the study’s overall yield range, ‘maximums recorded in this study of 11.07 to 14.14 kg.m-2’). Three of the six treatment cells (Module I both cultivars, Module III Starfighter) have no yield number in text - only Figure 2G bar chart with Tukey letters, no values given in running text or a table - so their AP/HYD yield cells are NR per the never-read-a-figure rule (SCHEMA.md). Discussion (p.7) separately states the study’s overall ‘maximums recorded… of 11.07 to 14.14 kg.m-2’; 14.14 matches the Tropicana-Module-II value above, but 11.07 is not attributed to any specific one of the six cells anywhere in the paper, so it is not entered in any row’s yield cell. | NO COLUMN / figure-only agronomic data (this paper reports almost all of its biometric and physiological data ONLY as Tukey-lettered bar charts, with no accompanying table and only three numeric yield values anywhere in running text - see plant.csv and the note’s Extraction notes for the full inventory): root length and root fresh/dry weight (ns, p>0.05, Supplementary Figure S2); stem fresh/dry weight (significant for module, cultivar and interaction, p<0.02, Figure 2A-B - modules II/III favor greater stem biomass, Tropicana > Starfighter); leaf fresh weight (ns, p>0.05, Figure 2C); leaf dry weight (Tropicana Module III significantly greater than Starfighter Module I, p<0.05, Figure 2D); head fresh/dry weight (Tropicana Module III significantly greater than Starfighter Module I, other combinations similar, p<0.05, Figure 2E-F); plant height (significant among treatments, p<0.05, Figure 3 - Tropicana Module III tallest, Module I smallest); total chlorophyll content (significant, p<0.05, Figure 4A - Module II highest regardless of cultivar); nitrate reductase (NR) enzymatic activity (significant for both factors, p<0.05, Figure 4B - Tropicana Module II highest); SPAD index (ns, p>0.3, Supplementary Figure S3). PPFD/PAR microclimate monitoring data (Appendix A, Supplementary Figure S4: NASA POWER-derived 21.47 MJ.m-2.day-1 global radiation / 9.87 MJ.m-2.day-1 PAR; in-mesh PPFD by module: Module I 558, Module II 580.76, Module III 558.82 umol.m-2.s-1, versus open-air control 943.67 umol.m-2.s-1 at noon). Relative stem-elongation claim (Discussion p.7: ‘Tropicana comparatively increased these parameters by 80%’) - basis/denominator for the 80% figure is not stated (which parameter, relative to which comparator), so not mapped to any cell.
pastorarbuluEnhancingGrowthYield2025-T4
Water
| Field | Value |
|---|---|
| Water volume in the system | 1,100 L (single shared nutrient-solution reservoir feeding all three NFT modules together via one 372.85 W recirculation pump; not partitioned per module, cultivar, or treatment, Methods 2.2, p.3) |
| Water type | La Molina hydroponic nutrient solution (Valderrama et al., 2020, cited); mineral nutrient solution, not fish-derived (Methods 2.2, p.3) |
Plant
| Field | Value |
|---|---|
| Plant | Lettuce (Lactuca sativa L.), cv. Starfighter |
| Details | Curly-type, heat-tolerant cultivar (Johnny’s Selected Seeds, Winslow, ME, USA); sown in quarry-sand substrate (0.5-1.00 mm) for germination/screening; transplanted to 4 cm pots at day 8; transplanted into NFT Module II channels 12 days later (day 20); harvested 48 days after germination / 25 days after channel transplant (Methods 2.2-2.3, p.3) |
| Days Plant after transplant | 25 |
| Tissue nitrate HYD | NR (this paper measures nitrate REDUCTASE ENZYMATIC ACTIVITY in leaf tissue, not tissue nitrate concentration - a different assay; see plant.csv/note) |
System & Setup
| Field | Value |
|---|---|
| System type | Pyramidal-layout NFT system (Module II), 13 channels, 7.5 cm diameter x 3 m length, within a 1.5 m-wide framework (Methods 2.3, p.3) |
| Media Details | No growth media used - NFT roots are submerged directly in a thin (<=3 mm) recirculating nutrient film, no substrate (Introduction, p.2). Channel/pipe diameter stated as 7.5 cm (75 mm) for this module in the module-specific description (Methods 2.3, p.3), but a separate, earlier general-NFT-description passage (Introduction, p.2) states ‘PVC pipes with a diameter of 110 mm served as growth channels’ for the system overall. See Experimental Remarks, WARN-MATERIAL, for the conflict; 7.5 cm/75 mm used here as it is the module-specific, thrice-independently-repeated figure. |
| Nutrient supplemented | Y (All treatments fed via recirculating La Molina hydroponic mineral nutrient solution (Valderrama et al., 2020); solution formulation held constant across modules/cultivars - only NFT module design and cultivar were varied as treatment factors (Methods 2.2, p.3)) |
| Equipment | SPAD 502-Plus portable chlorophyll meter; Quantum Light Meter (PPFD monitoring); 372.85 W electric recirculation pump; temperature-controlled oven (70 degC, 48 h, biomass drying); spectrophotometer for total chlorophyll (Lichtenthaler and Wellburn, 1983; Wellburn, 1994 methods, with modifications); nitrate reductase activity assay per Neyra and Hageman (1974) (Methods 2.5, p.3) |
| Control Parameters | 50% shade mesh; NFT solution film height max 3 mm; single shared 1,100 L reservoir + 372.85 W pump feeding both pyramidal and horizontal modules; channel slope 1-5% (Introduction p.2, Methods 2.1-2.2) |
| Combination | Lettuce (Lactuca sativa L.) cvs. Tropicana and Starfighter grown in a 2x3 factorial (cultivar x NFT module design) completely randomized design; this row = Module II x Starfighter |
Site
| Field | Value |
|---|---|
| Region | South America |
| Country | Peru |
| Lat | -12.07982 |
| Long | -76.94774 |
| Average room Temperature | 25.82 degC day / 20.43 degC night, average; max 31.5 degC, min 15.6 degC during the trial; 66.4% relative humidity; 50% shade mesh used to reduce radiation/heat load (Methods 2.1, p.3, Supplementary Table S1) |
Results & Statistics
| Field | Value |
|---|---|
| Measured Unit | kg.m-2 (yield, only cells with a stated number); g/plant and cm (fresh/dry weight by organ, plant height, root length - all figure-only, no unit-bearing numeric values extracted); SPAD units and total-chlorophyll/NR-activity units not given in text (figure-only); umol.m-2.s-1 (PPFD) |
| Statistic Details | Factorial ANOVA (2 cultivars x 3 NFT modules) + Tukey’s HSD (p<0.05) after verifying normality and homogeneity of variance; Pearson correlation between total chlorophyll and nitrate reductase (NR) activity, r=0.548, p<0.01 (Figure 5); Minitab 19 or Python (Methods 2.7, p.3) |
| Statistically analysed | Y |
| Replicates (n) | 10 |
| HYD | 13.45 kg/m2 |
Experimental Remarks: TRIAL DEFINITION: this row = NFT Module II (Pyramidal layout, 13 channels) x cultivar ‘Starfighter’, one cell of the paper’s 2 (cultivar) x 3 (module) completely randomized factorial design (Methods 2.3, p.3), n=10 replicate plants per treatment cell (60 plants total sampled 48 days after germination). No hydroponic control distinct from this design exists - all six cells ARE the trial; there is no separate baseline treatment, so HYD columns carry this cell’s own value and AP columns are NA throughout (no aquaponic arm anywhere in this paper - see Extraction notes in the note file for the trial-count judgment call, six rows one per cultivar x module combination, rather than three module-pooled rows or two cultivar-pooled rows, because the paper reports significant module x cultivar interaction effects, p<0.02-0.05, on stem biomass and yield, so pooling across either factor would discard the interaction the paper itself found significant). Paired ‘Tropicana’ cultivar in the same module is recorded as a separate sibling trial row. | WARN-MATERIAL channel/pipe diameter: Introduction (p.2) states generically ‘PVC pipes with a diameter of 110 mm served as growth channels’ for the NFT system description; Methods 2.3 (p.3) states, once per module (three times total, identical figure each time), that channels measure ‘7.5 cm in diameter’ (Module I, II and III alike). 110 mm and 75 mm are not a rounding difference (~1.47x apart) and describe what reads as the same physical growth channel. Recorded 7.5 cm/75 mm in Media Details (the module-specific, three-times-repeated figure, versus the single generic-description sentence); 110 mm preserved here as the other candidate. Affects: Media Details only; no dedicated schema column exists for a single pipe-diameter value that this would otherwise change. | WARN-MINOR total cultivation duration: Methods 2.2 states seedlings were transplanted into channels ‘12 days later’ than the first (day-8) transplant (day 20), then ‘For 25 days, the plants were nourished daily via the hydroponic nutrient film technique (NFT) system’ (day 20 to day 45); Results 3.1 (p.4) instead states plants were harvested ‘48 days after germination’. 20+25=45, not 48 - a 3-day gap. Both the Methods ‘25 days’ figure and the Results 3.1 restatement (‘almost ready for harvesting after 25 days of mineral solution supply and recirculation’, p.4) agree with each other and directly state the from-transplant duration, so 25 was recorded in Days Plant after transplant (not derived from 48-20); the 48-day germination-to-harvest total does not have its own dedicated column and does not conflict with the transplant-to-harvest figure used here, so no cell is affected beyond this note. | NOT DERIVED, left NR: Plants/m2 (Methods 2.3, p.3, states ‘120, 190 and 150 lettuce plants are harvested in modules I, II and III, respectively’ over a stated 4.5 m2 per module, citing Rodriguez-Delfin et al. 2022 - these totals describe the modules’ general production capacity per that citation, not necessarily this study’s own 60-day/60-plant experimental harvest; dividing count by area for either reading would be derivation, so left NR here with both raw inputs given); Water recycle (L/min not stated, only pump wattage 372.85 W, Methods 2.2, p.3 - converting wattage to a flow rate would be derivation). | Yield for this specific treatment cell: 13.45 kg/m2 (Abstract: ‘closely followed by Starfighter in module II’). Three of the six treatment cells (Module I both cultivars, Module III Starfighter) have no yield number in text - only Figure 2G bar chart with Tukey letters, no values given in running text or a table - so their AP/HYD yield cells are NR per the never-read-a-figure rule (SCHEMA.md). Discussion (p.7) separately states the study’s overall ‘maximums recorded… of 11.07 to 14.14 kg.m-2’; 14.14 matches the Tropicana-Module-II value above, but 11.07 is not attributed to any specific one of the six cells anywhere in the paper, so it is not entered in any row’s yield cell. | NO COLUMN / figure-only agronomic data (this paper reports almost all of its biometric and physiological data ONLY as Tukey-lettered bar charts, with no accompanying table and only three numeric yield values anywhere in running text - see plant.csv and the note’s Extraction notes for the full inventory): root length and root fresh/dry weight (ns, p>0.05, Supplementary Figure S2); stem fresh/dry weight (significant for module, cultivar and interaction, p<0.02, Figure 2A-B - modules II/III favor greater stem biomass, Tropicana > Starfighter); leaf fresh weight (ns, p>0.05, Figure 2C); leaf dry weight (Tropicana Module III significantly greater than Starfighter Module I, p<0.05, Figure 2D); head fresh/dry weight (Tropicana Module III significantly greater than Starfighter Module I, other combinations similar, p<0.05, Figure 2E-F); plant height (significant among treatments, p<0.05, Figure 3 - Tropicana Module III tallest, Module I smallest); total chlorophyll content (significant, p<0.05, Figure 4A - Module II highest regardless of cultivar); nitrate reductase (NR) enzymatic activity (significant for both factors, p<0.05, Figure 4B - Tropicana Module II highest); SPAD index (ns, p>0.3, Supplementary Figure S3). PPFD/PAR microclimate monitoring data (Appendix A, Supplementary Figure S4: NASA POWER-derived 21.47 MJ.m-2.day-1 global radiation / 9.87 MJ.m-2.day-1 PAR; in-mesh PPFD by module: Module I 558, Module II 580.76, Module III 558.82 umol.m-2.s-1, versus open-air control 943.67 umol.m-2.s-1 at noon). Relative stem-elongation claim (Discussion p.7: ‘Tropicana comparatively increased these parameters by 80%’) - basis/denominator for the 80% figure is not stated (which parameter, relative to which comparator), so not mapped to any cell.
pastorarbuluEnhancingGrowthYield2025-T5
Water
| Field | Value |
|---|---|
| Water volume in the system | 1,100 L (single shared nutrient-solution reservoir feeding all three NFT modules together via one 372.85 W recirculation pump; not partitioned per module, cultivar, or treatment, Methods 2.2, p.3) |
| Water type | La Molina hydroponic nutrient solution (Valderrama et al., 2020, cited); mineral nutrient solution, not fish-derived (Methods 2.2, p.3) |
Plant
| Field | Value |
|---|---|
| Plant | Lettuce (Lactuca sativa L.), cv. Tropicana |
| Details | Curly-type, heat-tolerant cultivar (Johnny’s Selected Seeds, Winslow, ME, USA); sown in quarry-sand substrate (0.5-1.00 mm) for germination/screening; transplanted to 4 cm pots at day 8; transplanted into NFT Module III channels 12 days later (day 20); harvested 48 days after germination / 25 days after channel transplant (Methods 2.2-2.3, p.3) |
| Days Plant after transplant | 25 |
| Tissue nitrate HYD | NR (this paper measures nitrate REDUCTASE ENZYMATIC ACTIVITY in leaf tissue, not tissue nitrate concentration - a different assay; see plant.csv/note) |
System & Setup
| Field | Value |
|---|---|
| System type | Pyramidal-layout NFT system (Module III), 10 channels, 7.5 cm diameter x 3 m length, within a 1.5 m-wide framework (Methods 2.3, p.3) |
| Media Details | No growth media used - NFT roots are submerged directly in a thin (<=3 mm) recirculating nutrient film, no substrate (Introduction, p.2). Channel/pipe diameter stated as 7.5 cm (75 mm) for this module in the module-specific description (Methods 2.3, p.3), but a separate, earlier general-NFT-description passage (Introduction, p.2) states ‘PVC pipes with a diameter of 110 mm served as growth channels’ for the system overall. See Experimental Remarks, WARN-MATERIAL, for the conflict; 7.5 cm/75 mm used here as it is the module-specific, thrice-independently-repeated figure. |
| Nutrient supplemented | Y (All treatments fed via recirculating La Molina hydroponic mineral nutrient solution (Valderrama et al., 2020); solution formulation held constant across modules/cultivars - only NFT module design and cultivar were varied as treatment factors (Methods 2.2, p.3)) |
| Equipment | SPAD 502-Plus portable chlorophyll meter; Quantum Light Meter (PPFD monitoring); 372.85 W electric recirculation pump; temperature-controlled oven (70 degC, 48 h, biomass drying); spectrophotometer for total chlorophyll (Lichtenthaler and Wellburn, 1983; Wellburn, 1994 methods, with modifications); nitrate reductase activity assay per Neyra and Hageman (1974) (Methods 2.5, p.3) |
| Control Parameters | 50% shade mesh; NFT solution film height max 3 mm; single shared 1,100 L reservoir + 372.85 W pump feeding both pyramidal and horizontal modules; channel slope 1-5% (Introduction p.2, Methods 2.1-2.2) |
| Combination | Lettuce (Lactuca sativa L.) cvs. Tropicana and Starfighter grown in a 2x3 factorial (cultivar x NFT module design) completely randomized design; this row = Module III x Tropicana |
Site
| Field | Value |
|---|---|
| Region | South America |
| Country | Peru |
| Lat | -12.07982 |
| Long | -76.94774 |
| Average room Temperature | 25.82 degC day / 20.43 degC night, average; max 31.5 degC, min 15.6 degC during the trial; 66.4% relative humidity; 50% shade mesh used to reduce radiation/heat load (Methods 2.1, p.3, Supplementary Table S1) |
Results & Statistics
| Field | Value |
|---|---|
| Measured Unit | kg.m-2 (yield, only cells with a stated number); g/plant and cm (fresh/dry weight by organ, plant height, root length - all figure-only, no unit-bearing numeric values extracted); SPAD units and total-chlorophyll/NR-activity units not given in text (figure-only); umol.m-2.s-1 (PPFD) |
| Statistic Details | Factorial ANOVA (2 cultivars x 3 NFT modules) + Tukey’s HSD (p<0.05) after verifying normality and homogeneity of variance; Pearson correlation between total chlorophyll and nitrate reductase (NR) activity, r=0.548, p<0.01 (Figure 5); Minitab 19 or Python (Methods 2.7, p.3) |
| Statistically analysed | Y |
| Replicates (n) | 10 |
| HYD | 13.96 kg/m2 |
Experimental Remarks: TRIAL DEFINITION: this row = NFT Module III (Pyramidal layout, 10 channels) x cultivar ‘Tropicana’, one cell of the paper’s 2 (cultivar) x 3 (module) completely randomized factorial design (Methods 2.3, p.3), n=10 replicate plants per treatment cell (60 plants total sampled 48 days after germination). No hydroponic control distinct from this design exists - all six cells ARE the trial; there is no separate baseline treatment, so HYD columns carry this cell’s own value and AP columns are NA throughout (no aquaponic arm anywhere in this paper - see Extraction notes in the note file for the trial-count judgment call, six rows one per cultivar x module combination, rather than three module-pooled rows or two cultivar-pooled rows, because the paper reports significant module x cultivar interaction effects, p<0.02-0.05, on stem biomass and yield, so pooling across either factor would discard the interaction the paper itself found significant). Paired ‘Starfighter’ cultivar in the same module is recorded as a separate sibling trial row. | WARN-MATERIAL channel/pipe diameter: Introduction (p.2) states generically ‘PVC pipes with a diameter of 110 mm served as growth channels’ for the NFT system description; Methods 2.3 (p.3) states, once per module (three times total, identical figure each time), that channels measure ‘7.5 cm in diameter’ (Module I, II and III alike). 110 mm and 75 mm are not a rounding difference (~1.47x apart) and describe what reads as the same physical growth channel. Recorded 7.5 cm/75 mm in Media Details (the module-specific, three-times-repeated figure, versus the single generic-description sentence); 110 mm preserved here as the other candidate. Affects: Media Details only; no dedicated schema column exists for a single pipe-diameter value that this would otherwise change. | WARN-MINOR total cultivation duration: Methods 2.2 states seedlings were transplanted into channels ‘12 days later’ than the first (day-8) transplant (day 20), then ‘For 25 days, the plants were nourished daily via the hydroponic nutrient film technique (NFT) system’ (day 20 to day 45); Results 3.1 (p.4) instead states plants were harvested ‘48 days after germination’. 20+25=45, not 48 - a 3-day gap. Both the Methods ‘25 days’ figure and the Results 3.1 restatement (‘almost ready for harvesting after 25 days of mineral solution supply and recirculation’, p.4) agree with each other and directly state the from-transplant duration, so 25 was recorded in Days Plant after transplant (not derived from 48-20); the 48-day germination-to-harvest total does not have its own dedicated column and does not conflict with the transplant-to-harvest figure used here, so no cell is affected beyond this note. | NOT DERIVED, left NR: Plants/m2 (Methods 2.3, p.3, states ‘120, 190 and 150 lettuce plants are harvested in modules I, II and III, respectively’ over a stated 4.5 m2 per module, citing Rodriguez-Delfin et al. 2022 - these totals describe the modules’ general production capacity per that citation, not necessarily this study’s own 60-day/60-plant experimental harvest; dividing count by area for either reading would be derivation, so left NR here with both raw inputs given); Water recycle (L/min not stated, only pump wattage 372.85 W, Methods 2.2, p.3 - converting wattage to a flow rate would be derivation). | Yield for this specific treatment cell: 13.96 kg/m2 (Abstract). Three of the six treatment cells (Module I both cultivars, Module III Starfighter) have no yield number in text - only Figure 2G bar chart with Tukey letters, no values given in running text or a table - so their AP/HYD yield cells are NR per the never-read-a-figure rule (SCHEMA.md). Discussion (p.7) separately states the study’s overall ‘maximums recorded… of 11.07 to 14.14 kg.m-2’; 14.14 matches the Tropicana-Module-II value above, but 11.07 is not attributed to any specific one of the six cells anywhere in the paper, so it is not entered in any row’s yield cell. | NO COLUMN / figure-only agronomic data (this paper reports almost all of its biometric and physiological data ONLY as Tukey-lettered bar charts, with no accompanying table and only three numeric yield values anywhere in running text - see plant.csv and the note’s Extraction notes for the full inventory): root length and root fresh/dry weight (ns, p>0.05, Supplementary Figure S2); stem fresh/dry weight (significant for module, cultivar and interaction, p<0.02, Figure 2A-B - modules II/III favor greater stem biomass, Tropicana > Starfighter); leaf fresh weight (ns, p>0.05, Figure 2C); leaf dry weight (Tropicana Module III significantly greater than Starfighter Module I, p<0.05, Figure 2D); head fresh/dry weight (Tropicana Module III significantly greater than Starfighter Module I, other combinations similar, p<0.05, Figure 2E-F); plant height (significant among treatments, p<0.05, Figure 3 - Tropicana Module III tallest, Module I smallest); total chlorophyll content (significant, p<0.05, Figure 4A - Module II highest regardless of cultivar); nitrate reductase (NR) enzymatic activity (significant for both factors, p<0.05, Figure 4B - Tropicana Module II highest); SPAD index (ns, p>0.3, Supplementary Figure S3). PPFD/PAR microclimate monitoring data (Appendix A, Supplementary Figure S4: NASA POWER-derived 21.47 MJ.m-2.day-1 global radiation / 9.87 MJ.m-2.day-1 PAR; in-mesh PPFD by module: Module I 558, Module II 580.76, Module III 558.82 umol.m-2.s-1, versus open-air control 943.67 umol.m-2.s-1 at noon). Relative stem-elongation claim (Discussion p.7: ‘Tropicana comparatively increased these parameters by 80%’) - basis/denominator for the 80% figure is not stated (which parameter, relative to which comparator), so not mapped to any cell.
pastorarbuluEnhancingGrowthYield2025-T6
Water
| Field | Value |
|---|---|
| Water volume in the system | 1,100 L (single shared nutrient-solution reservoir feeding all three NFT modules together via one 372.85 W recirculation pump; not partitioned per module, cultivar, or treatment, Methods 2.2, p.3) |
| Water type | La Molina hydroponic nutrient solution (Valderrama et al., 2020, cited); mineral nutrient solution, not fish-derived (Methods 2.2, p.3) |
Plant
| Field | Value |
|---|---|
| Plant | Lettuce (Lactuca sativa L.), cv. Starfighter |
| Details | Curly-type, heat-tolerant cultivar (Johnny’s Selected Seeds, Winslow, ME, USA); sown in quarry-sand substrate (0.5-1.00 mm) for germination/screening; transplanted to 4 cm pots at day 8; transplanted into NFT Module III channels 12 days later (day 20); harvested 48 days after germination / 25 days after channel transplant (Methods 2.2-2.3, p.3) |
| Days Plant after transplant | 25 |
| Tissue nitrate HYD | NR (this paper measures nitrate REDUCTASE ENZYMATIC ACTIVITY in leaf tissue, not tissue nitrate concentration - a different assay; see plant.csv/note) |
System & Setup
| Field | Value |
|---|---|
| System type | Pyramidal-layout NFT system (Module III), 10 channels, 7.5 cm diameter x 3 m length, within a 1.5 m-wide framework (Methods 2.3, p.3) |
| Media Details | No growth media used - NFT roots are submerged directly in a thin (<=3 mm) recirculating nutrient film, no substrate (Introduction, p.2). Channel/pipe diameter stated as 7.5 cm (75 mm) for this module in the module-specific description (Methods 2.3, p.3), but a separate, earlier general-NFT-description passage (Introduction, p.2) states ‘PVC pipes with a diameter of 110 mm served as growth channels’ for the system overall. See Experimental Remarks, WARN-MATERIAL, for the conflict; 7.5 cm/75 mm used here as it is the module-specific, thrice-independently-repeated figure. |
| Nutrient supplemented | Y (All treatments fed via recirculating La Molina hydroponic mineral nutrient solution (Valderrama et al., 2020); solution formulation held constant across modules/cultivars - only NFT module design and cultivar were varied as treatment factors (Methods 2.2, p.3)) |
| Equipment | SPAD 502-Plus portable chlorophyll meter; Quantum Light Meter (PPFD monitoring); 372.85 W electric recirculation pump; temperature-controlled oven (70 degC, 48 h, biomass drying); spectrophotometer for total chlorophyll (Lichtenthaler and Wellburn, 1983; Wellburn, 1994 methods, with modifications); nitrate reductase activity assay per Neyra and Hageman (1974) (Methods 2.5, p.3) |
| Control Parameters | 50% shade mesh; NFT solution film height max 3 mm; single shared 1,100 L reservoir + 372.85 W pump feeding both pyramidal and horizontal modules; channel slope 1-5% (Introduction p.2, Methods 2.1-2.2) |
| Combination | Lettuce (Lactuca sativa L.) cvs. Tropicana and Starfighter grown in a 2x3 factorial (cultivar x NFT module design) completely randomized design; this row = Module III x Starfighter |
Site
| Field | Value |
|---|---|
| Region | South America |
| Country | Peru |
| Lat | -12.07982 |
| Long | -76.94774 |
| Average room Temperature | 25.82 degC day / 20.43 degC night, average; max 31.5 degC, min 15.6 degC during the trial; 66.4% relative humidity; 50% shade mesh used to reduce radiation/heat load (Methods 2.1, p.3, Supplementary Table S1) |
Results & Statistics
| Field | Value |
|---|---|
| Measured Unit | kg.m-2 (yield, only cells with a stated number); g/plant and cm (fresh/dry weight by organ, plant height, root length - all figure-only, no unit-bearing numeric values extracted); SPAD units and total-chlorophyll/NR-activity units not given in text (figure-only); umol.m-2.s-1 (PPFD) |
| Statistic Details | Factorial ANOVA (2 cultivars x 3 NFT modules) + Tukey’s HSD (p<0.05) after verifying normality and homogeneity of variance; Pearson correlation between total chlorophyll and nitrate reductase (NR) activity, r=0.548, p<0.01 (Figure 5); Minitab 19 or Python (Methods 2.7, p.3) |
| Statistically analysed | Y |
| Replicates (n) | 10 |
Experimental Remarks: TRIAL DEFINITION: this row = NFT Module III (Pyramidal layout, 10 channels) x cultivar ‘Starfighter’, one cell of the paper’s 2 (cultivar) x 3 (module) completely randomized factorial design (Methods 2.3, p.3), n=10 replicate plants per treatment cell (60 plants total sampled 48 days after germination). No hydroponic control distinct from this design exists - all six cells ARE the trial; there is no separate baseline treatment, so HYD columns carry this cell’s own value and AP columns are NA throughout (no aquaponic arm anywhere in this paper - see Extraction notes in the note file for the trial-count judgment call, six rows one per cultivar x module combination, rather than three module-pooled rows or two cultivar-pooled rows, because the paper reports significant module x cultivar interaction effects, p<0.02-0.05, on stem biomass and yield, so pooling across either factor would discard the interaction the paper itself found significant). Paired ‘Tropicana’ cultivar in the same module is recorded as a separate sibling trial row. | WARN-MATERIAL channel/pipe diameter: Introduction (p.2) states generically ‘PVC pipes with a diameter of 110 mm served as growth channels’ for the NFT system description; Methods 2.3 (p.3) states, once per module (three times total, identical figure each time), that channels measure ‘7.5 cm in diameter’ (Module I, II and III alike). 110 mm and 75 mm are not a rounding difference (~1.47x apart) and describe what reads as the same physical growth channel. Recorded 7.5 cm/75 mm in Media Details (the module-specific, three-times-repeated figure, versus the single generic-description sentence); 110 mm preserved here as the other candidate. Affects: Media Details only; no dedicated schema column exists for a single pipe-diameter value that this would otherwise change. | WARN-MINOR total cultivation duration: Methods 2.2 states seedlings were transplanted into channels ‘12 days later’ than the first (day-8) transplant (day 20), then ‘For 25 days, the plants were nourished daily via the hydroponic nutrient film technique (NFT) system’ (day 20 to day 45); Results 3.1 (p.4) instead states plants were harvested ‘48 days after germination’. 20+25=45, not 48 - a 3-day gap. Both the Methods ‘25 days’ figure and the Results 3.1 restatement (‘almost ready for harvesting after 25 days of mineral solution supply and recirculation’, p.4) agree with each other and directly state the from-transplant duration, so 25 was recorded in Days Plant after transplant (not derived from 48-20); the 48-day germination-to-harvest total does not have its own dedicated column and does not conflict with the transplant-to-harvest figure used here, so no cell is affected beyond this note. | NOT DERIVED, left NR: Plants/m2 (Methods 2.3, p.3, states ‘120, 190 and 150 lettuce plants are harvested in modules I, II and III, respectively’ over a stated 4.5 m2 per module, citing Rodriguez-Delfin et al. 2022 - these totals describe the modules’ general production capacity per that citation, not necessarily this study’s own 60-day/60-plant experimental harvest; dividing count by area for either reading would be derivation, so left NR here with both raw inputs given); Water recycle (L/min not stated, only pump wattage 372.85 W, Methods 2.2, p.3 - converting wattage to a flow rate would be derivation). | Yield for this specific treatment cell: NR. Three of the six treatment cells (Module I both cultivars, Module III Starfighter) have no yield number in text - only Figure 2G bar chart with Tukey letters, no values given in running text or a table - so their AP/HYD yield cells are NR per the never-read-a-figure rule (SCHEMA.md). Discussion (p.7) separately states the study’s overall ‘maximums recorded… of 11.07 to 14.14 kg.m-2’; 14.14 matches the Tropicana-Module-II value above, but 11.07 is not attributed to any specific one of the six cells anywhere in the paper, so it is not entered in any row’s yield cell. | NO COLUMN / figure-only agronomic data (this paper reports almost all of its biometric and physiological data ONLY as Tukey-lettered bar charts, with no accompanying table and only three numeric yield values anywhere in running text - see plant.csv and the note’s Extraction notes for the full inventory): root length and root fresh/dry weight (ns, p>0.05, Supplementary Figure S2); stem fresh/dry weight (significant for module, cultivar and interaction, p<0.02, Figure 2A-B - modules II/III favor greater stem biomass, Tropicana > Starfighter); leaf fresh weight (ns, p>0.05, Figure 2C); leaf dry weight (Tropicana Module III significantly greater than Starfighter Module I, p<0.05, Figure 2D); head fresh/dry weight (Tropicana Module III significantly greater than Starfighter Module I, other combinations similar, p<0.05, Figure 2E-F); plant height (significant among treatments, p<0.05, Figure 3 - Tropicana Module III tallest, Module I smallest); total chlorophyll content (significant, p<0.05, Figure 4A - Module II highest regardless of cultivar); nitrate reductase (NR) enzymatic activity (significant for both factors, p<0.05, Figure 4B - Tropicana Module II highest); SPAD index (ns, p>0.3, Supplementary Figure S3). PPFD/PAR microclimate monitoring data (Appendix A, Supplementary Figure S4: NASA POWER-derived 21.47 MJ.m-2.day-1 global radiation / 9.87 MJ.m-2.day-1 PAR; in-mesh PPFD by module: Module I 558, Module II 580.76, Module III 558.82 umol.m-2.s-1, versus open-air control 943.67 umol.m-2.s-1 at noon). Relative stem-elongation claim (Discussion p.7: ‘Tropicana comparatively increased these parameters by 80%’) - basis/denominator for the 80% figure is not stated (which parameter, relative to which comparator), so not mapped to any cell.
Plant Measurements
| Trial | System | Category | Analyte | Value | Unit | Sig. | Location |
|---|---|---|---|---|---|---|---|
| pastorarbuluEnhancingGrowthYield2025-T1 | Module I - Tropicana | biochemistry | Total chlorophyll content | NR | NR | p<0.05 (overall ANOVA, significant among treatments); module II highest regardless of cultivar (Results 3.3, p.5) | Figure 4A, p.6 |
| pastorarbuluEnhancingGrowthYield2025-T1 | Module I - Tropicana | biochemistry | SPAD index (relative chlorophyll) | NR | NR | ns, p>0.3 (Results 3.3, p.5) | Supplementary Figure S3 |
| pastorarbuluEnhancingGrowthYield2025-T2 | Module I - Starfighter | biochemistry | Total chlorophyll content | NR | NR | p<0.05 (overall ANOVA, significant among treatments); module II highest regardless of cultivar (Results 3.3, p.5) | Figure 4A, p.6 |
| pastorarbuluEnhancingGrowthYield2025-T2 | Module I - Starfighter | biochemistry | SPAD index (relative chlorophyll) | NR | NR | ns, p>0.3 (Results 3.3, p.5) | Supplementary Figure S3 |
| pastorarbuluEnhancingGrowthYield2025-T3 | Module II - Tropicana | biochemistry | Total chlorophyll content | NR | NR | p<0.05 (overall ANOVA, significant among treatments); module II highest regardless of cultivar (Results 3.3, p.5) | Figure 4A, p.6 |
| pastorarbuluEnhancingGrowthYield2025-T3 | Module II - Tropicana | biochemistry | SPAD index (relative chlorophyll) | NR | NR | ns, p>0.3 (Results 3.3, p.5) | Supplementary Figure S3 |
| pastorarbuluEnhancingGrowthYield2025-T4 | Module II - Starfighter | biochemistry | Total chlorophyll content | NR | NR | p<0.05 (overall ANOVA, significant among treatments); module II highest regardless of cultivar (Results 3.3, p.5) | Figure 4A, p.6 |
| pastorarbuluEnhancingGrowthYield2025-T4 | Module II - Starfighter | biochemistry | SPAD index (relative chlorophyll) | NR | NR | ns, p>0.3 (Results 3.3, p.5) | Supplementary Figure S3 |
| pastorarbuluEnhancingGrowthYield2025-T5 | Module III - Tropicana | biochemistry | Total chlorophyll content | NR | NR | p<0.05 (overall ANOVA, significant among treatments); module II highest regardless of cultivar (Results 3.3, p.5) | Figure 4A, p.6 |
| pastorarbuluEnhancingGrowthYield2025-T5 | Module III - Tropicana | biochemistry | SPAD index (relative chlorophyll) | NR | NR | ns, p>0.3 (Results 3.3, p.5) | Supplementary Figure S3 |
| pastorarbuluEnhancingGrowthYield2025-T6 | Module III - Starfighter | biochemistry | Total chlorophyll content | NR | NR | p<0.05 (overall ANOVA, significant among treatments); module II highest regardless of cultivar (Results 3.3, p.5) | Figure 4A, p.6 |
| pastorarbuluEnhancingGrowthYield2025-T6 | Module III - Starfighter | biochemistry | SPAD index (relative chlorophyll) | NR | NR | ns, p>0.3 (Results 3.3, p.5) | Supplementary Figure S3 |