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Article

Root Pruning Enhances Leaf Oxidative Stress and Anthocyanin Accumulation in Hydroponically Grown Red Leaf Lettuce

by
Masaru Sakamoto
* and
Takahiro Suzuki
Faculty of Biology-Oriented Science and Technology, Kindai University, Wakayama 649-6493, Japan
*
Author to whom correspondence should be addressed.
Oxygen 2025, 5(4), 24; https://doi.org/10.3390/oxygen5040024 (registering DOI)
Submission received: 4 September 2025 / Revised: 31 October 2025 / Accepted: 20 November 2025 / Published: 22 November 2025
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Abstract

Root pruning has been proposed as a practical method to regulate growth and metabolite accumulation in horticultural crops, yet its physiological and metabolic consequences in hydroponically grown lettuce remain poorly understood. In this study, we examined the effects of root pruning, applied two days before harvest, on biomass production, oxidative stress responses, and metabolite accumulation in red leaf lettuce. Root pruning suppressed root growth and reduced root water content in a severity-dependent manner. Shoot fresh weight also declined, whereas shoot dry weight was significantly reduced only under severe pruning. Young leaves of pruned plants exhibited transient reddish coloration, which was most pronounced under severe pruning. Quantitative analyses revealed that anthocyanin content increased up to 4.5-fold compared with the control, while total phenolic content also rose significantly. These metabolic changes were accompanied by pronounced oxidative stress, as indicated by elevated hydrogen peroxide accumulation and enhanced lipid peroxidation. In addition, leaf nitrate concentration decreased significantly in both moderate and severe pruning treatments. Collectively, these findings demonstrate that root pruning acts as a controllable stressor that triggers oxidative stress signaling, enhances antioxidant metabolite accumulation, and reduces nitrate content, highlighting its potential as a pre-harvest strategy for improving the nutritional and functional quality of hydroponic lettuce.

1. Introduction

Plant roots are fundamental organs responsible for water and nutrient uptake, thereby sustaining plant growth, development, and the accumulation of bioactive compounds. However, plant performance is frequently constrained by fluctuations in the root-zone environment. Factors such as salinity, temperature stress, hypoxia, and drought are well known to limit growth [1,2,3,4]. Among these, drought stress is particularly critical. When roots perceive drought, abscisic acid (ABA) biosynthesis is induced, leading to stomatal closure in shoots and reduced water loss through transpiration [5]. Drought stress also enhances oxidative stress in both roots and leaves, thereby stimulating the accumulation of antioxidant compounds such as phenolics [6,7]. Anthocyanins, which are major phenolic compounds, are frequently induced under drought conditions and contribute to the mitigation of oxidative damage by scavenging reactive oxygen species (ROS) through their hydroxyl groups, thereby protecting plant cells from oxidative injury [8,9,10].
In lettuce, the predominant phenolic compounds include caffeic acid derivatives such as chicoric and chlorogenic acids, as well as flavonoids such as quercetin and luteolin glycosides, which are recognized for their strong antioxidant properties [11]. In red leaf lettuce, cyanidin-3-O-(6″-malonylglucoside) and cyanidin-3-O-glucoside are the predominant anthocyanins responsible for red pigmentation, greatly contributing to both the nutritional value and visual appeal of the crop [12]. The accumulation of these anthocyanins is strongly influenced by nitrate availability in the growth medium: high nitrate supply tends to suppress anthocyanin biosynthesis, whereas nitrate limitation triggers a stress-related activation of anthocyanin accumulation [13,14]. This relationship provides a useful framework for optimizing cultivation strategies aimed at improving both the nutritional quality and aesthetic characteristics of red leaf lettuce.
Hydroponic cultivation provides a powerful platform for examining such responses because the root-zone environment can be precisely controlled compared to soil-based systems. Root-zone manipulation in hydroponics has been widely applied to regulate shoot growth and alter metabolite accumulation. For example, reducing root-zone temperature induces oxidative stress and stimulates anthocyanin accumulation in leaves [15,16]. Similarly, exposing carrot storage roots to blue light increased anthocyanin levels [17]. Iron deficiencies in nutrient solutions have also been shown to promote anthocyanin biosynthesis in leaves [18]. These studies highlight the utility of hydroponic systems for targeted regulation of secondary metabolism through precise control of root conditions.
In addition to environmental regulation, direct manipulation of root systems has gained attention as a horticultural practice. Root pruning and root restriction, in particular, have been investigated as strategies to optimize growth performance and enhance metabolite production [19,20]. Root pruning is also widely used in fruit and vegetable crops such as citrus, apple, and strawberry to regulate vegetative growth, improve fruit quality, and enhance nutrient use efficiency [21,22,23]. This practice has potential as a sustainable method to improve crop quality while reducing excessive vegetative growth, making it valuable for modern horticultural production [24]. Adjusting the root-to-shoot ratio has been shown to increase phenolic content and essential oil accumulation in basil grown under aeroponic systems [25]. Root restriction affects multiple physiological processes, including biomass accumulation, leaf gas exchange, water and nutrient uptake, chlorophyll content, root respiration, flowering, and yield [19,26]. Interestingly, while root restriction often reduces vegetative growth, it can simultaneously stimulate metabolite accumulation. For example, in hydroponically grown pepper and tomato, root restriction increased soluble sugars, starch, fructose, sucrose, and glucose despite reduced overall growth [27,28]. Similarly, in Agastache rugosa, root pruning increased shoot concentrations of rosmarinic acid and tilianin [29]. These findings suggest that root pruning may induce drought-like stress responses, partly through ABA production, thereby enhancing secondary metabolism.
Previous studies in hydroponic lettuce have shown that root pruning suppresses root and shoot growth shortly after treatment, followed by shoot growth recovery as root regeneration occurs [30]. Severe root pruning after harvest, however, has been reported to accelerate weight loss and reduce freshness in lettuce [31]. Despite these insights, little is known about how root pruning during cultivation affects the accumulation of bioactive compounds in hydroponically grown lettuce. Therefore, the present study aimed to investigate the effects of different intensities of root pruning, applied two days before harvest, on biomass production and the accumulation of bioactive compounds such as anthocyanins in red leaf lettuce cultivated under hydroponic conditions.

2. Materials and Methods

2.1. Experimental Conditions

Seeds of red leaf lettuce (Lactuca sativa L. cv. Red Wave; Sakata Seed Co., Yokohama, Japan) were sown in sponge cubes (2 × 2 × 2 cm) at 20 °C under a photosynthetic photon flux density (PPFD) of 200 μmol·m−2·s−1 provided by fluorescent lamps (FL40SBR-A; NEC Co., Tokyo, Japan). A 16 h light/8 h dark photoperiod was applied throughout germination. During this period, seedlings were irrigated with half-strength Otsuka House A-recipe nutrient solution (OAT Agrio Co., Ltd., Tokyo, Japan) following the protocol described by Sakamoto et al. [32]. Fourteen days after sowing, seedlings were transplanted into a deep flow technique (DFT) hydroponic system with continuous aeration. After transplanting, plants were grown at 22 ± 2 °C with continuous aeration. Environmental conditions were maintained at a PPFD of 250 μmol·m−2·s−1 and a 16 h light cycle.
Root pruning treatments were applied on day 19 after sowing. Three intensities of pruning were examined. In the light pruning treatment, roots were trimmed at 3 cm from the base. In the moderate pruning treatment, roots were cut at 2 cm from the base, which corresponded to the length of the sponge cube; thus, only roots extending beyond the cube were removed. In the severe pruning treatment, roots were shortened to 1 cm from the base by removing the lower half of the sponge cube. Control plants remained intact without root removal. To ensure stable positioning of both pruned and control plants within the hydroponic system, an additional urethane support was placed around the sponge cubes.

2.2. Measurement of Leaf Redness

Leaf redness was quantified using a colorimeter (NR10QC, Guangdong Threenh Technology Co., Ltd., Shenzhen, China), following the method of Sakamoto et al. [17]. The CIE a* value was used as an index of red coloration.

2.3. Histochemical Detection of Hydrogen Peroxide

Hydrogen peroxide accumulation was visualized with a modified protocol from Sakamoto et al. [33]. Leaf disks (7 mm diameter) were excised from the fourth true leaves one day after root pruning using a hole punch. Disks were incubated in 1 mg·mL−1 3,3′-diaminobenzidine (DAB) solution (pH 3.8) for 3 h. Disks were boiled in 90% ethanol at 95 °C for 3 min to remove the chlorophyll. After cooling, stained tissues were observed under a stereomicroscope.

2.4. Determination of Anthocyanin Content

Anthocyanin concentration was quantified spectrophotometrically [17]. Fourth true leaves (50 mg) were homogenized in 1 mL of 90% methanol containing 1% hydrochloric acid and centrifuged at 10,000× g for 5 min. Absorbance of the supernatant was measured at 533 nm. Total anthocyanin content was calculated using a cyanidin-3-glucoside standard curve.

2.5. Determination of Total Phenolic Content

Total phenolic content was determined using a modified Folin–Ciocalteu assay [34]. Fourth true leaves (50 mg) were homogenized in 500 µL of 90% methanol and centrifuged at 10,000× g for 5 min. The supernatant (20 µL) was mixed with 680 µL distilled water, 50 µL Folin–Ciocalteu reagent, and 300 µL of 5% sodium carbonate. After incubation in the dark at 25 °C for 30 min, absorbance was measured at 765 nm. Gallic acid was used to construct the standard calibration curve.

2.6. Determination of Hydrogen Peroxide

Hydrogen peroxide content was determined spectrophotometrically using a modified version of the method described by [34]. Fourth true leaves (100 mg) were homogenized in 600 μL of 1% trichloroacetic acid (TCA) solution. After centrifugation, 250 μL of the supernatant was combined with 250 μL of 10 mM potassium phosphate buffer (pH 7.0) and 500 μL of 1 M potassium iodide (KI) solution. The absorbance of each reaction mixture was measured at 390 nm using a spectrophotometer.

2.7. Determination of Lipid Peroxidation

Lipid peroxidation was evaluated by measuring malondialdehyde (MDA) content using the thiobarbituric acid reactive substances (TBARS) assay [34]. Fourth true leaves (100 mg) were homogenized in 0.5 mL of 0.1% trichloroacetic acid (TCA) and centrifuged at 10,000× g for 5 min. An aliquot of the supernatant (0.2 mL) was mixed with 0.8 mL of 0.5% thiobarbituric acid (TBA) in 20% TCA. The reaction mixture was incubated at 95 °C for 30 min, rapidly cooled on ice, and centrifuged again at 10,000× g for 5 min. Absorbance of the supernatant was measured at 532 nm, with nonspecific absorbance at 600 nm subtracted.

2.8. Determination of Nitrate Content

Nitrate concentration was determined following the method of Sakamoto et al. [34]. The fourth true leaves or roots samples (50 mg) were homogenized in 1 mL of deionized water, and the homogenate was filtered through filter paper. Nitrate content was measured using a reflectometer (RQflex plus) and commercial nitrate test strips (Merck, Darmstadt, Germany).

2.9. Data Analysis

Each treatment consisted of six biological replicates (n = 6), and each replicate corresponded to an individual plant. For measurements of leaf redness, the second, third, and fourth leaves were analyzed using twelve biological replicates (n = 12). For the time-course analysis of leaf redness, four biological replicates (n = 4) were used. The raw data used for all measurements are provided in the Supplementary Tables S1–S19. All statistical analyses were conducted using R version 4.2.0 (R Core Team, Vienna, Austria). One-way analysis of variance (ANOVA) was applied to assess differences among treatments, followed by Tukey’s honestly significant difference (HSD) test for multiple comparisons. Statistical significance was considered at p < 0.05.

3. Results

3.1. Root Morphological and Physiological Changes

Root morphology was examined two days after root pruning. In root-pruned plants, overall root length was shorter than in the control (Figure 1). Under moderate pruning, in which all roots protruding from the urethane block were removed, new roots emerged from the outer surface of the block. In contrast, very few new roots extended beyond the urethane under severe pruning (Figure 1).
Measurements of root biomass revealed that both fresh weight and dry weight decreased in a pruning-intensity–dependent manner (Figure 2A,B). Root water content was significantly reduced under severe pruning (Figure 2C).

3.2. Shoot Morphological Response and Leaf Coloration

Root pruning induced visible changes in shoot morphology two days after root pruning. Young leaves of pruned plants exhibited distinct reddish coloration compared to the control (Figure 3). The intensity of this coloration increased proportionally with the severity of root pruning. Colorimetric analysis supported these visual observations. The redness (a* value) of the fourth true leaf increased progressively with pruning severity (Figure 4A). Although the third true leaf exhibited lower a* values than the fourth, it also responded to pruning in a severity-dependent manner (Figure 4B). In the second true leaf, redness was further reduced overall, but still showed a detectable response to root pruning (Figure 4C). A time-course analysis of the fourth true leaf revealed that redness increased in a pruning-intensity–dependent manner at 1 and 2 days after treatment. However, these differences diminished by day 3, and by day 7, pigmentation levels across all treatments were comparable to the control (Figure 4D).

3.3. Shoot Biomass and Water Status

Shoot fresh weight showed a tendency to decrease under moderate pruning and was significantly reduced under severe pruning (Figure 5A). Dry weight significantly decreased only in the severe pruning treatment (Figure 5B). Shoot water content followed a similar trend to fresh weight, with significant reductions under moderate pruning and further decreases under severe pruning (Figure 5C).

3.4. Shoot Anthocyanin Accumulation and Total Phenolic Content

Because red pigmentation in red leaf lettuce is primarily attributable to anthocyanins [15], anthocyanin content in the fourth leaf was quantified two days after pruning. Anthocyanin accumulation increased in moderate and severe pruning, reaching approximately 3.0-fold higher than the control under moderate pruning and 4.5-fold higher under severe pruning (Figure 6A). Total phenolic content also tended to increase under moderate pruning and was significantly higher under severe pruning (Figure 6B).

3.5. Shoot Oxidative Stress

Since phenolic compounds are known to accumulate under oxidative stress conditions [8,9,10], we next examined ROS in lettuce leaves. Histochemical staining with DAB revealed increased hydrogen peroxide accumulation in the fourth leaf one day after severe pruning (Figure 7A). To confirm this observation, hydrogen peroxide content was quantified two days after treatment (Figure 7B). The results showed that severe pruning significantly increased hydrogen peroxide levels compared with the control. Consistent with this, lipid peroxidation, measured as MDA, was also significantly elevated under severe pruning (Figure 7C).

3.6. Shoot Nitrate Content

Because root pruning is known to affect nutrient uptake, particularly nitrogen and phosphorus [20], leaf nitrate content was analyzed. Nitrate concentration decreased significantly in both moderate and severe pruning treatments compared with the control (Figure 8).

4. Discussion

4.1. Root Pruning and Drought-like Stress

Root pruning has been reported to induce drought-like stress in several perennial fruit trees, such as apple, grape, peach, and pear [35,36]. Drought stress is typically associated with reduced tissue water content and the activation of ABA signaling pathways, which regulate various physiological responses including stomatal closure and gene expression related to stress tolerance [5,37,38]. Notably, ABA accumulation has also been observed in response to root pruning [36,39,40]. In our study, both moderate and severe pruning significantly lowered root and leaf water content, indicating that hydroponically grown lettuce also experienced drought-like stress after root removal. Water deficit is closely linked to oxidative stress, as reduced water availability often enhances the generation of ROS in leaves [41,42]. Histochemical staining using DAB has shown hydrogen peroxide accumulation in leaves of various species under drought stress [43,44,45,46]. Consistently, our results revealed hydrogen peroxide accumulation and increased lipid peroxidation under severe pruning, providing strong evidence that oxidative stress was induced. Similar findings were reported in hydroponic lettuce exposed to low-temperature stress, where hydrogen peroxide accumulation was strongly induced in leaves [15]. These results suggest that disturbances in root function are quickly translated into shoot stress signals, which then trigger biochemical and physiological adjustments.

4.2. Root Pruning and Plant Growth

The influence of root pruning on plant growth varies depending on pruning intensity and crop species [29,47,48,49,50]. For instance, in hydroponically grown Agastache rugosa, shoot biomass decreased after >70% pruning but was unaffected at ≤50% pruning [29]. Similarly, our earlier research on carrot demonstrated that taproot pruning reduced belowground biomass while having little effect on shoot growth [50]. This is likely because many fine roots, which are essential for water uptake, remain functional after partial pruning, thus sustaining shoot growth even when storage organs are reduced. Consistent with these observations, light pruning in our lettuce experiment did not significantly alter shoot biomass. Hydroponic lettuce has been shown to allocate greater biomass to roots [51], which may, in turn, buffer against the impacts of root loss in light pruning treatment in this study. In contrast, moderate pruning reduced shoot fresh weight but not dry weight, suggesting that water uptake was temporarily impaired but photosynthetic carbon assimilation remained stable. Severe pruning, however, reduced both fresh and dry weight, indicating suppression of photosynthesis. These results demonstrate that severe root pruning can mimic drought stress, restricting both water availability and carbon assimilation, whereas moderate pruning exerts only partial stress. Therefore, adjusting the intensity of root pruning offers a means of inducing controlled stress in shoots without necessarily compromising photosynthesis.

4.3. Root Pruning and Leaf Metabolites

One of the most notable outcomes of root pruning was the alteration of leaf secondary metabolites, especially anthocyanins. Accumulation was most prominent in young leaves, which are generally more responsive to environmental cues. This observation is consistent with earlier findings that young leaves exhibit greater sensitivity to oxidative stress and stronger activation of anthocyanin biosynthesis pathways [52,53,54]. In lettuce, young leaves have been reported to respond more strongly to light-induced anthocyanin accumulation than older leaves [54]. Conversely, old leaves often show higher sensitivity to root-related oxidative stress [55,56]. Considering that ROS are known to trigger anthocyanin biosynthesis [57], our findings suggest that root pruning induced oxidative stress in leaves, which promoted anthocyanin accumulation particularly in young tissues. This interpretation is further supported by the observed increases in hydrogen peroxide and malondialdehyde. Anthocyanin accumulation was transient: levels increased at one and two days after pruning but returned to control levels by day seven. This decline likely reflected root recovery, as new root emergence was observed after moderate pruning. Restoration of root function would reduce stress signaling, thereby diminishing the induction of anthocyanin biosynthesis. Such transient responses align with recent reports that stress-induced anthocyanin accumulation is often temporary if the stress is alleviated [58]. Root pruning also significantly influenced nutrient composition. Both moderate and severe treatments reduced nitrate concentrations in leaves, consistent with reports that nitrate uptake is highly sensitive to root impairment [20,59,60,61]. Interestingly, nitrate levels declined similarly under both treatments, but shoot biomass was more strongly reduced under severe pruning. This suggests that severe pruning not only restricted nutrient uptake but also impaired carbon assimilation, thereby compounding growth suppression.

4.4. Pre-Harvest Strategies for Component Regulation

Applying short-term environmental stresses before harvest is a promising strategy for enhancing crop quality while minimizing yield loss [62,63,64]. Previous studies have shown that ultraviolet-A irradiation or temporary nutrient deficiencies can increase antioxidant compounds and reduce nitrate content without severely affecting biomass [65,66]. Our findings suggest that root pruning can function as a complementary pre-harvest strategy. Moderate pruning two days before harvesting enhanced anthocyanin accumulation and reduced nitrate levels, while having little effect on shoot dry weight. Importantly, these results demonstrate that root pruning can be tuned to induce temporary oxidative stress and metabolite accumulation without fully inhibiting photosynthesis. Moderate pruning, in particular, appears to strike a balance between inducing beneficial stress responses and maintaining shoot growth, making it a potentially valuable tool for horticultural crop management. Hydroponic systems provide an ideal platform for such interventions, as root-zone conditions can be manipulated precisely and uniformly across production units [67]. This controllability enhances the practicality of root pruning for quality regulation compared with soil-based systems. Future research should focus on refining the timing and intensity of pruning relative to harvest and exploring its integration with other pre-harvest treatments such as light manipulation or nutrient adjustments.

5. Conclusions

In summary, root pruning in hydroponically grown red leaf lettuce not only modifies growth but also functions as a pre-harvest strategy for quality improvement. Moderate pruning induced temporary oxidative stress, enhanced anthocyanin accumulation, and reduced nitrate concentration without major growth penalties. These findings highlight root pruning as a practical and controllable approach to optimizing both the nutritional and functional traits of leafy vegetables, contributing to sustainable and high-value horticultural production.

Supplementary Materials

The following supporting information can be downloaded at: https://www.mdpi.com/article/10.3390/oxygen5040024/s1, Table S1: Raw data of root fresh weight (mg); Table S2: Raw data of root dry weight (mg); Table S3: Raw data of root water content (%); Table S4: Raw data of a value (fourth leaf); Table S5: Raw data of a value (third leaf); Table S6: Raw data of a value (second leaf); Table S7: Raw data of a value (day 1); Table S8: Raw data of a value (day 2); Table S9: Raw data of a value (day 3); Table S10: Raw data of a value (day 5); Table S11: Raw data of a value (day 7); Table S12: Raw data of shoot fresh weight (g); Table S13: Raw data of shoot dry weight (mg); Table S14: Raw data of shoot water content (%); Table S15: Raw data of anthocyanin content (μg/gFW); Table S16: Raw data of total phenol content (μg/gFW); Table S17: Raw data of hydrogen peroxide (μgmol/gFW); Table S18: Raw data of MDA content (μg/gFW); Table S19: Raw data of nitrate content (μg/gFW).

Author Contributions

Conceptualization, M.S. and T.S.; formal analysis, M.S.; investigation, M.S.; writing—original draft preparation, M.S.; writing—review and editing, M.S. and T.S. All authors have read and agreed to the published version of the manuscript.

Funding

This research received no external funding.

Data Availability Statement

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

Conflicts of Interest

The authors declare no conflicts of interest.

References

  1. Anjum, S.A.; Ashraf, U.; Zohaib, A.; Tanveer, M.; Naeem, M.; Ali, I.; Tabassum, T.; Nazir, U. Growth and Developmental Responses of Crop Plants under Drought Stress: A Review. Zemdirb. Agric. 2017, 104, 267–276. [Google Scholar] [CrossRef]
  2. Balasubramaniam, T.; Shen, G.; Esmaeili, N.; Zhang, H. Plants’ Response Mechanisms to Salinity Stress. Plants 2023, 12, 2253. [Google Scholar] [CrossRef]
  3. Zhang, H.; Sun, X.; Song, W. Physiological and Growth Characteristics of Tomato Seedlings in Response to Low Root-Zone Temperature. HortScience 2023, 58, 442–448. [Google Scholar] [CrossRef]
  4. Daniel, K.; Hartman, S. How Plant Roots Respond to Waterlogging. J. Exp. Bot. 2024, 75, 511–525. [Google Scholar] [CrossRef] [PubMed]
  5. Muhammad Aslam, M.; Waseem, M.; Jakada, B.H.; Okal, E.J.; Lei, Z.; Saqib, H.S.A.; Yuan, W.; Xu, W.; Zhang, Q. Mechanisms of Abscisic Acid-Mediated Drought Stress Responses in Plants. Int. J. Mol. Sci. 2022, 23, 1084. [Google Scholar] [CrossRef] [PubMed]
  6. Gharibi, S.; Tabatabaei, B.E.S.; Saeidi, G.; Goli, S.A.H. Effect of Drought Stress on Total Phenolic, Lipid Peroxidation, and Antioxidant Activity of Achillea Species. Appl. Biochem. Biotechnol. 2016, 178, 796–809. [Google Scholar] [CrossRef]
  7. Rahimi, M.; Kordrostami, M.; Mohamadhasani, F.; Chaeikar, S.S. Antioxidant Gene Expression Analysis and Evaluation of Total Phenol Content and Oxygen-Scavenging System in Tea Accessions under Normal and Drought Stress Conditions. BMC Plant Biol. 2021, 21, 494. [Google Scholar] [CrossRef]
  8. Sperdouli, I.; Moustakas, M. Interaction of Proline, Sugars, and Anthocyanins during Photosynthetic Acclimation of Arabidopsis thaliana to Drought Stress. J. Plant Physiol. 2012, 169, 577–585. [Google Scholar] [CrossRef]
  9. Jan, R.; Asif, S.; Asaf, S.; Lubna; Khan, Z.; Kim, K.-M. Unveiling the Protective Role of Anthocyanin in Rice: Insights into Drought-Induced Oxidative Stress and Metabolic Regulation. Front. Plant Sci. 2024, 15, 1397817. [Google Scholar] [CrossRef]
  10. Medina-Lozano, I.; Bertolín, J.R.; Díaz, A. Impact of Drought Stress on Vitamin C and Anthocyanin Content in Cultivated Lettuces (Lactuca sativa L.) and Wild Relatives (Lactuca spp.). Front. Plant Sci. 2024, 15, 1369658. [Google Scholar] [CrossRef]
  11. Llorach, R.; Martínez-Sánchez, A.; Tomás-Barberán, F.A.; Gil, M.I.; Ferreres, F. Characterisation of Polyphenols and Antioxidant Properties of Five Lettuce Varieties and Escarole. Food Chem. 2008, 108, 1028–1038. [Google Scholar] [CrossRef] [PubMed]
  12. Kim, D.-E.; Shang, X.; Assefa, A.D.; Keum, Y.-S.; Saini, R.K. Metabolite Profiling of Green, Green/Red, and Red Lettuce Cultivars: Variation in Health Beneficial Compounds and Antioxidant Potential. Food Res. Int. 2018, 105, 361–370. [Google Scholar] [CrossRef] [PubMed]
  13. Liu, C.; Yu, H.; Liu, Y.; Zhang, L.; Li, D.; Zhao, X.; Zhang, J.; Sui, Y. Promoting Anthocyanin Biosynthesis in Purple Lettuce through Sucrose Supplementation under Nitrogen Limitation. Horticulturae 2024, 10, 838. [Google Scholar] [CrossRef]
  14. Liang, Y.; Dong, Y.; Yang, Q.; Urano, D.; Wang, Z. Interactive Effects of Light Quality and Nitrate Supply on Growth and Metabolic Processes in Two Lettuce Cultivars (Lactuca sativa L.). Environ. Exp. Bot. 2023, 213, 105443. [Google Scholar] [CrossRef]
  15. Sakamoto, M.; Suzuki, T. Effect of Root-Zone Temperature on Growth and Quality of Hydroponically Grown Red Leaf Lettuce (Lactuca sativa L. cv. Red Wave). Am. J. Plant Sci. 2015, 06, 2350. [Google Scholar] [CrossRef]
  16. Wittayathanarattana, T.; Wanichananan, P.; Supaibulwatana, K.; Goto, E. A Short-Term Cooling of Root-Zone Temperature Increases Bioactive Compounds in Baby Leaf Amaranthus tricolor L. Front. Plant Sci. 2022, 13, 944716. [Google Scholar] [CrossRef]
  17. Sakamoto, M.; Funaki, A.; Sakagami, F.; Kaida, T.; Suzuki, T. Unveiling the Impact of LED Light on Growing Carrot Taproots: A Novel Hydroponic Cultivation System. Eng 2025, 6, 87. [Google Scholar] [CrossRef]
  18. Caramanico, L.; Rustioni, L.; De Lorenzis, G. Iron Deficiency Stimulates Anthocyanin Accumulation in Grapevine Apical Leaves. Plant Physiol. Biochem. 2017, 119, 286–293. [Google Scholar] [CrossRef]
  19. Shi, K.; Ding, X.-T.; Dong, D.-K.; Zhou, Y.-H.; Yu, J.-Q. Root Restriction-Induced Limitation to Photosynthesis in Tomato (Lycopersicon esculentum Mill.) Leaves. Sci. Hortic. 2008, 117, 197–202. [Google Scholar] [CrossRef]
  20. Jing, D.; Du, Z.; Wang, M.; Wang, Q.; Ma, H.; Liu, F.; Ma, B.; Dong, Y. Regulatory Effects of Root Pruning on Leaf Nutrients, Photosynthesis, and Growth of Trees in a Closed-Canopy Poplar Plantation. PLoS ONE 2018, 13, e0197515. [Google Scholar] [CrossRef]
  21. Budiarto, R.; Poerwanto, R.; Santosa, E.; Efendi, D. A Review of Root Pruning to Regulate Citrus Growth. J. Trop. Crop Sci. 2019, 6, 1–7. [Google Scholar] [CrossRef]
  22. Fang, C.; Zhou, K.; Zhang, Y.; Li, B.; Han, M. Effect of Root Pruning and Nitrogen Fertilization on Growth of Young ‘Fuji’ Apple (Malus domestica Borkh.) Trees. J. Plant Nutr. 2017, 40, 1538–1546. [Google Scholar] [CrossRef]
  23. Kwon, J.K.; Kang, S.W.; Paek, Y.; Moon, J.P.; Jang, J.K.; Oh, S.S. Effects of Local Cooling and Root Pruning on Budding and Local Heating on Heating Energy Consumption in Forcing Cultivation of Strawberry. J. Bio-Environ. Control 2019, 28, 46–54. [Google Scholar] [CrossRef]
  24. Mathiyazhagan, K.; Subash, M.; Bose, C. Root Pruning—A Growth Regulation Practice in Fruit Crops. CABI Rev. 2021, 16, 1–12. [Google Scholar] [CrossRef]
  25. Salachas, G.; Savvas, D.; Argyropoulou, K.; Tarantillis, P.; Kapotis, G. Yield and Nutritional Quality of Aeroponically Cultivated Basil as Affected by the Available Root-Zone Volume. Emir. J. Food Agric. 2015, 27, 911. [Google Scholar] [CrossRef]
  26. Kharkina, T.G.; Ottosen, C.-O.; Rosenqvist, E. Effects of Root Restriction on the Growth and Physiology of Cucumber Plants. Physiol. Plant. 1999, 105, 434–441. [Google Scholar] [CrossRef]
  27. Nishizawa, T.; Saito, K. Effects of Rooting Volume Restriction on the Growth and Carbohydrate Concentration in Tomato Plants. J. Am. Soc. Hortic. Sci. 1998, 123, 581–585. [Google Scholar] [CrossRef]
  28. Al-Debei, H.; Mugnai, S. Starch Accumulation in the Leaves of Root-Restricted Pepper Affects Plant Growth by a Feedback-Inhibition of the Photosynthesis. Adv. Hortic. Sci. 2011, 25, 253–259. [Google Scholar] [CrossRef]
  29. Lam, V.P.; Kim, S.J.; Lee, H.J.; Park, J.S. Root Pruning Increased Bioactive Compounds of Hydroponically-Grown Agastache rugosa in a Greenhouse. Hortic. Environ. Biotechnol. 2019, 60, 647–657. [Google Scholar] [CrossRef]
  30. Biddington, N.L.; Dearman, A.S. Shoot and Root Growth of Lettuce Seedlings Following Root Pruning. Ann. Bot. 1984, 53, 663–668. [Google Scholar] [CrossRef]
  31. Suo, R.; Wang, W.; Ma, Y.; Fu, L.; Cui, Y. Effect of Different Root Lengths for Retaining Freshness of Hydroponic Lettuce. J. Agric. Food Res. 2021, 4, 100151. [Google Scholar] [CrossRef]
  32. Sakamoto, M.; Suzuki, T. Effect of Nutrient Solution Concentration on the Growth of Hydroponic Sweetpotato. Agronomy 2020, 10, 1708. [Google Scholar] [CrossRef]
  33. Sakamoto, M.; Suzuki, T. Methyl Jasmonate and Salinity Increase Anthocyanin Accumulation in Radish Sprouts. Horticulturae 2019, 5, 62. [Google Scholar] [CrossRef]
  34. Sakamoto, M.; Suzuki, T. N-Acetylcysteine Mitigates Oxidative Stress Induced by Transplanting Lettuce Seedlings into a DFT Hydroponic System. Agronomy 2024, 14, 2112. [Google Scholar] [CrossRef]
  35. Poni, S.; Tagliavini, M.; Neri, D.; Scudellari, D.; Toselli, M. Influence of Root Pruning and Water Stress on Growth and Physiological Factors of Potted Apple, Grape, Peach and Pear Trees. Sci. Hortic. 1992, 52, 223–236. [Google Scholar] [CrossRef]
  36. Wang, Y.; Bertelsen, M.G.; Petersen, K.K.; Andersen, M.N.; Liu, F. Effect of Root Pruning and Irrigation Regimes on Leaf Water Relations and Xylem ABA and Ionic Concentrations in Pear Trees. Agric. Water Manag. 2014, 135, 84–89. [Google Scholar] [CrossRef]
  37. Patanè, C.; Cosentino, S.L.; Romano, D.; Toscano, S. Relative Water Content, Proline, and Antioxidant Enzymes in Leaves of Long Shelf-Life Tomatoes under Drought Stress and Rewatering. Plants 2022, 11, 3045. [Google Scholar] [CrossRef]
  38. Yan, S.; Weng, B.; Jing, L.; Bi, W. Effects of Drought Stress on Water Content and Biomass Distribution in Summer Maize (Zea mays L.). Front. Plant Sci. 2023, 14, 1118131. [Google Scholar] [CrossRef]
  39. Yan, M.; Zhang, C.; Li, H.; Zhang, L.; Ren, Y.; Chen, Y.; Cai, H.; Zhang, S. Root Pruning Improves Maize Water-Use Efficiency by Root Water Absorption. Front. Plant Sci. 2023, 13, 1023088. [Google Scholar] [CrossRef]
  40. Smith, P.G.; Dale, J.E. The Effects of Root Cooling and Excision Treatments on the Growth of Primary Leaves of Phaseolus vulgar is L. New Phytol. 1988, 110, 293–300. [Google Scholar] [CrossRef]
  41. Ahluwalia, O.; Singh, P.C.; Bhatia, R. A Review on Drought Stress in Plants: Implications, Mitigation and the Role of Plant Growth Promoting Rhizobacteria. Resour. Environ. Sustain. 2021, 5, 100032. [Google Scholar] [CrossRef]
  42. Haghpanah, M.; Hashemipetroudi, S.; Arzani, A.; Araniti, F. Drought Tolerance in Plants: Physiological and Molecular Responses. Plants 2024, 13, 2962. [Google Scholar] [CrossRef] [PubMed]
  43. Huseynova, I.M.; Aliyeva, D.R.; Mammadov, A.C.; Aliyev, J.A. Hydrogen Peroxide Generation and Antioxidant Enzyme Activities in the Leaves and Roots of Wheat Cultivars Subjected to Long-Term Soil Drought Stress. Photosynth. Res. 2015, 125, 279–289. [Google Scholar] [CrossRef]
  44. Xia, L.; Yang, L.; Sun, N.; Li, J.; Fang, Y.; Wang, Y. Physiological and Antioxidant Enzyme Gene Expression Analysis Reveals the Improved Tolerance to Drought Stress of the Somatic Hybrid Offspring of Brassica napus and Sinapis alba at Vegetative Stage. Acta Physiol. Plant 2016, 38, 88. [Google Scholar] [CrossRef]
  45. Sezgin, A.; Altuntaş, C.; Sağlam, A.; Terzi, R.; Demiralay, M.; Kadıoğlu, A. Abscisic Acid Cross-Talking with Hydrogen Peroxide and Osmolyte Compounds May Regulate the Leaf Rolling Mechanism under Drought. Acta Physiol. Plant 2018, 40, 141. [Google Scholar] [CrossRef]
  46. Yan, Y.; Wang, P.; Lu, Y.; Bai, Y.; Wei, Y.; Liu, G.; Shi, H. MeRAV5 Promotes Drought Stress Resistance in Cassava by Modulating Hydrogen Peroxide and Lignin Accumulation. Plant J. 2021, 107, 847–860. [Google Scholar] [CrossRef]
  47. Jing, D.-W.; Liu, F.-C.; Wang, M.-Y.; Ma, H.-L.; Du, Z.-Y.; Ma, B.-Y.; Dong, Y.-F. Effects of Root Pruning on the Physicochemical Properties and Microbial Activities of Poplar Rhizosphere Soil. PLoS ONE 2017, 12, e0187685. [Google Scholar] [CrossRef]
  48. Yang, S.; Xing, S.; Liu, C.; Du, Z.; Wang, H.; Xu, Y. Effects of Root Pruning on the Vegetative Growth and Fruit Quality of Zhanhuadongzao Trees. Hortic. Sci. 2010, 37, 14–21. [Google Scholar] [CrossRef]
  49. Yang, S.; Zhang, Y.; Deng, J.; Li, R.; Fan, X.; Dao, J.; Quan, Y.; Bukhari, S.A.H. Effect of Cutting Depth during Sugarcane (Saccharum spp. Hybrid) Harvest on Root Characteristics and Yield. PLoS ONE 2021, 16, e0238085. [Google Scholar] [CrossRef]
  50. Sakamoto, M.; Wada, M.; Suzuki, T. Effect of Partial Excision of Early Taproots on Growth and Components of Hydroponic Carrots. Horticulturae 2020, 6, 5. [Google Scholar] [CrossRef]
  51. Lei, C.; Engeseth, N.J. Comparison of Growth Characteristics, Functional Qualities, and Texture of Hydroponically Grown and Soil-Grown Lettuce. LWT 2021, 150, 111931. [Google Scholar] [CrossRef]
  52. Zhou, Q.; Chen, Z.; Lee, J.; Li, X.; Sun, W. Proteomic Analysis of Tea Plants (Camellia sinensis) with Purple Young Shoots during Leaf Development. PLoS ONE 2017, 12, e0177816. [Google Scholar] [CrossRef]
  53. Lee, J.-H.; Goto, E. Ozone Control as a Novel Method to Improve Health-Promoting Bioactive Compounds in Red Leaf Lettuce (Lactuca sativa L.). Front. Plant Sci. 2022, 13, 1045239. [Google Scholar] [CrossRef] [PubMed]
  54. Nagano, S.; Mori, N.; Tomari, Y.; Mitsugi, N.; Deguchi, A.; Kashima, M.; Tezuka, A.; Nagano, A.J.; Usami, H.; Tanabata, T.; et al. Effect of Differences in Light Source Environment on Transcriptome of Leaf Lettuce (Lactuca sativa L.) to Optimize Cultivation Conditions. PLoS ONE 2022, 17, e0265994. [Google Scholar] [CrossRef] [PubMed]
  55. AbdElgawad, H.; Zinta, G.; Hegab, M.M.; Pandey, R.; Asard, H.; Abuelsoud, W. High Salinity Induces Different Oxidative Stress and Antioxidant Responses in Maize Seedlings Organs. Front. Plant Sci. 2016, 7, 276. [Google Scholar] [CrossRef] [PubMed]
  56. AbdElgawad, H.; Zinta, G.; Hamed, B.A.; Selim, S.; Beemster, G.; Hozzein, W.N.; Wadaan, M.A.M.; Asard, H.; Abuelsoud, W. Maize Roots and Shoots Show Distinct Profiles of Oxidative Stress and Antioxidant Defense under Heavy Metal Toxicity. Environ. Pollut. 2020, 258, 113705. [Google Scholar] [CrossRef]
  57. Xu, Z.; Mahmood, K.; Rothstein, S.J. ROS Induces Anthocyanin Production Via Late Biosynthetic Genes and Anthocyanin Deficiency Confers the Hypersensitivity to ROS-Generating Stresses in Arabidopsis. Plant Cell Physiol. 2017, 58, 1364–1377. [Google Scholar] [CrossRef]
  58. Bykova, A.V.; Meleshin, A.A.; Shchennikova, A.V.; Kochieva, E.Z. Effect of Cold Stress on Anthocyanin Content and Anthocyanin Biosynthesis Pathway Gene Expression in Potato Solanum tuberosum L. Leaves. Russ. J. Genet. 2025, 61, 809–819. [Google Scholar] [CrossRef]
  59. Schäfer, E.D.; Owen, M.R.; Band, L.R.; Farcot, E.; Bennett, M.J.; Lynch, J.P. Modeling Root Loss Reveals Impacts on Nutrient Uptake and Crop Development. Plant Physiol. 2022, 190, 2260–2278. [Google Scholar] [CrossRef]
  60. Yu, X.; Wang, B.; Zhang, C.; Xu, W.; He, J.; Zhu, L.; Wang, S. Effect of Root Restriction on Nitrogen Levels and Glutamine Synthetase Activity in ‘Kyoho’ Grapevines. Sci. Hortic. 2012, 137, 156–163. [Google Scholar] [CrossRef]
  61. Yu, X.; Li, J.; Zhu, L.; Wang, B.; Wang, L.; Bai, Y.; Zhang, C.; Xu, W.; Wang, S. Effects of Root Restriction on Nitrogen and Gene Expression Levels in Nitrogen Metabolism in Jumeigui Grapevines (Vitis vinifera L. × Vitis labrusca L.). J. Integr. Agric. 2015, 14, 67–79. [Google Scholar] [CrossRef]
  62. Toscano, S.; Trivellini, A.; Cocetta, G.; Bulgari, R.; Francini, A.; Romano, D.; Ferrante, A. Effect of Preharvest Abiotic Stresses on the Accumulation of Bioactive Compounds in Horticultural Produce. Front. Plant Sci. 2019, 10, 1212. [Google Scholar] [CrossRef]
  63. Shao, C.; Zhang, C.; Lv, Z.; Shen, C. Pre- and Post-Harvest Exposure to Stress Influence Quality-Related Metabolites in Fresh Tea Leaves (Camellia sinensis). Sci. Hortic. 2021, 281, 109984. [Google Scholar] [CrossRef]
  64. Zhao, X.; Peng, J.; Zhang, L.; Yang, X.; Qiu, Y.; Cai, C.; Hu, J.; Huang, T.; Liang, Y.; Li, Z.; et al. Optimizing the Quality of Horticultural Crop: Insights into Pre-Harvest Practices in Controlled Environment Agriculture. Front. Plant Sci. 2024, 15, 1427471. [Google Scholar] [CrossRef]
  65. Sonjaroon, W.; Tepkaew, T.; Kupia, M.; Tongkok, P.; Boonkorkaew, P.; Thussagunpanit, J. Pre-Harvest UV-A Supplementation in Plant Factory with Artificial Lighting Improves Growth, Photosynthesis, and Phytonutrients in Kale. Horticulturae 2024, 10, 701. [Google Scholar] [CrossRef]
  66. Sakamoto, M.; Komatsu, Y.; Suzuki, T. Nutrient Deficiency Affects the Growth and Nitrate Concentration of Hydroponic Radish. Horticulturae 2021, 7, 525. [Google Scholar] [CrossRef]
  67. Balliu, A.; Zheng, Y.; Sallaku, G.; Fernández, J.A.; Gruda, N.S.; Tuzel, Y. Environmental and Cultivation Factors Affect the Morphology, Architecture and Performance of Root Systems in Soilless Grown Plants. Horticulturae 2021, 7, 243. [Google Scholar] [CrossRef]
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Figure 1. Representative root morphology of red leaf lettuce 2 days after root pruning. Scale bars represent 2 cm.
Figure 1. Representative root morphology of red leaf lettuce 2 days after root pruning. Scale bars represent 2 cm.
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Figure 2. Effects of root pruning on root biomass and water status of red leaf lettuce after 2 days of treatment. (A) Root fresh weight, (B) root dry weight, and (C) root water content. Values represent means ± SE (n = 6). Different letters indicate significant differences among treatments according to Tukey–Kramer test (p < 0.05).
Figure 2. Effects of root pruning on root biomass and water status of red leaf lettuce after 2 days of treatment. (A) Root fresh weight, (B) root dry weight, and (C) root water content. Values represent means ± SE (n = 6). Different letters indicate significant differences among treatments according to Tukey–Kramer test (p < 0.05).
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Figure 3. Representative shoot morphology of red leaf lettuce 2 days after root pruning. Scale bars represent 2 cm.
Figure 3. Representative shoot morphology of red leaf lettuce 2 days after root pruning. Scale bars represent 2 cm.
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Figure 4. Effects of root pruning on leaf redness of red leaf lettuce. (A) a* values of the fourth true leaf, (B) the third true leaf, and (C) the second true leaf measured 2 days after treatment. (D) Time-course of a* values in the fourth true leaf from 1 to 7 days after treatment. Values represent means ± SE (n = 12 for (A–C); n = 4 for (D)). Different letters indicate significant differences among treatments according to Tukey–Kramer test (p < 0.05).
Figure 4. Effects of root pruning on leaf redness of red leaf lettuce. (A) a* values of the fourth true leaf, (B) the third true leaf, and (C) the second true leaf measured 2 days after treatment. (D) Time-course of a* values in the fourth true leaf from 1 to 7 days after treatment. Values represent means ± SE (n = 12 for (A–C); n = 4 for (D)). Different letters indicate significant differences among treatments according to Tukey–Kramer test (p < 0.05).
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Figure 5. Effects of root pruning on shoot biomass and water status of red leaf lettuce after 2 days of treatment. (A) Shoot fresh weight, (B) shoot dry weight, and (C) shoot water content. Values represent means ± SE (n = 6). Different letters indicate significant differences among treatments according to Tukey–Kramer test (p < 0.05).
Figure 5. Effects of root pruning on shoot biomass and water status of red leaf lettuce after 2 days of treatment. (A) Shoot fresh weight, (B) shoot dry weight, and (C) shoot water content. Values represent means ± SE (n = 6). Different letters indicate significant differences among treatments according to Tukey–Kramer test (p < 0.05).
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Figure 6. Effects of root pruning on (A) anthocyanin content and (B) total phenolic content in leaves of red leaf lettuce after 2 days of treatment. Values represent means ± SE (n = 6). Different letters indicate significant differences among treatments according to Tukey–Kramer test (p < 0.05).
Figure 6. Effects of root pruning on (A) anthocyanin content and (B) total phenolic content in leaves of red leaf lettuce after 2 days of treatment. Values represent means ± SE (n = 6). Different letters indicate significant differences among treatments according to Tukey–Kramer test (p < 0.05).
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Figure 7. Oxidative stress responses in leaves of red leaf lettuce subjected to root pruning. (A) Histochemical detection of hydrogen peroxide in leaves 1 day after treatment using DAB staining. Scale bars represent 1 mm. Contents of (B) hydrogen peroxide and (C) Malondialdehyde (MDA) in leaves 2 days after treatment. Values represent means ± SE (n = 6). Different letters indicate significant differences among treatments according to Tukey–Kramer test (p < 0.05).
Figure 7. Oxidative stress responses in leaves of red leaf lettuce subjected to root pruning. (A) Histochemical detection of hydrogen peroxide in leaves 1 day after treatment using DAB staining. Scale bars represent 1 mm. Contents of (B) hydrogen peroxide and (C) Malondialdehyde (MDA) in leaves 2 days after treatment. Values represent means ± SE (n = 6). Different letters indicate significant differences among treatments according to Tukey–Kramer test (p < 0.05).
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Figure 8. Effects of root pruning on nitrate concentration in leaves of red leaf lettuce after 2 days of treatment. Values represent means ± SE (n = 6). Different letters indicate significant differences among treatments according to Tukey–Kramer test (p < 0.05).
Figure 8. Effects of root pruning on nitrate concentration in leaves of red leaf lettuce after 2 days of treatment. Values represent means ± SE (n = 6). Different letters indicate significant differences among treatments according to Tukey–Kramer test (p < 0.05).
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Sakamoto, M.; Suzuki, T. Root Pruning Enhances Leaf Oxidative Stress and Anthocyanin Accumulation in Hydroponically Grown Red Leaf Lettuce. Oxygen 2025, 5, 24. https://doi.org/10.3390/oxygen5040024

AMA Style

Sakamoto M, Suzuki T. Root Pruning Enhances Leaf Oxidative Stress and Anthocyanin Accumulation in Hydroponically Grown Red Leaf Lettuce. Oxygen. 2025; 5(4):24. https://doi.org/10.3390/oxygen5040024

Chicago/Turabian Style

Sakamoto, Masaru, and Takahiro Suzuki. 2025. "Root Pruning Enhances Leaf Oxidative Stress and Anthocyanin Accumulation in Hydroponically Grown Red Leaf Lettuce" Oxygen 5, no. 4: 24. https://doi.org/10.3390/oxygen5040024

APA Style

Sakamoto, M., & Suzuki, T. (2025). Root Pruning Enhances Leaf Oxidative Stress and Anthocyanin Accumulation in Hydroponically Grown Red Leaf Lettuce. Oxygen, 5(4), 24. https://doi.org/10.3390/oxygen5040024

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