Cho et al. (2025) Enhancing production efficiency of tomatoes through soil moisture–dependent multifaceted responses in three-layered soil

Identification

• Journal: Plant Physiology and Biochemistry
• Year: 2025
• Date: 2025-09-13
• Authors: Jwa Yeong Cho, Da Hye Ryu, Dae-Hyun Jung, Muhammad Hamayun, Taek Sung Lee, Soo Hyun Park, Hye Min Kim, Ho‐Youn Kim
• DOI: 10.1016/j.plaphy.2025.110443

Research Groups

• Smart Farm Research Center, Korea Institute of Science and Technology (KIST), Gangneung, Gangwon, Republic of Korea
• Department of Plant Pathology and Environmental Microbiology, The Pennsylvania State University, University Park, PA, USA
• Department of Smart Farm Science, Kyung Hee University, Yongin, Republic of Korea
• Department of Botany, Garden Campus, Abdul Wali Khan University Mardan, Mardan, Pakistan
• Natural Product Applied Science, KIST School, University of Science and Technology (UST), Gangneung, Gangwon, Republic of Korea

Short Summary

This study identified an optimal irrigation range for enhancing water use efficiency in tomato cultivation within a three-layered soil system by integrating real-time soil moisture monitoring with morpho-physiological and biochemical analyses, demonstrating that maintaining volumetric water content between 15% and 25% significantly improved irrigation water use efficiency without negatively affecting plant growth.

Objective

• To identify the optimal irrigation region for enhancing water use efficiency (WUE) in tomato cultivation by employing a multilateral experimental approach, integrating real-time soil moisture monitoring with morpho-physiological and biochemical analyses of plant responses to varying soil moisture levels in three-layered soil (TLS) systems.

Study Configuration

• Spatial Scale: Pot experiments (pots: 26.5 cm outer diameter, 24.5 cm inner diameter, 25 cm height; soil layers: 4 cm siliceous sand mulch, 4 cm manure, 13 cm clay). Field validation (planting density: 2.0 plants per square meter; three-layered soil: 4–6 cm siliceous sand mulch, 4–6 cm manure, >15 cm clay).
• Temporal Scale: Pot experiment (September 21, 2020 to October 21, 2020). Field validation (weekly measurements from October 15, 2021 to February 25, 2022).

Methodology and Data

• Models used: Linear regression model (for sensor calibration), Principal Component Analysis (PCA), Partial Least Squares-Discriminant Analysis (PLS-DA), One-way ANOVA (Duncan’s method), Student’s t-test, Irrigation Water Use Efficiency (IWUE) calculation (Y/I), irrigation scheduling based on accumulated solar radiation and accumulated evapotranspiration.
• Data sources:
  • Sensors: 5 TE capacitance sensors (for volumetric water content, VWC), VT-300 sensor module (for temperature, relative humidity, CO2), Vantage Pro2 DS6450 weather station (for solar radiation).
  • Plant measurements: LCi-SD portable photosynthesis system (for photosynthesis rate, transpiration, stomatal conductance), visual observation (morphological changes).
  • Biochemical analysis: Gas Chromatography coupled to Time-of-Flight Mass Spectrometer (GC-ToF-MS) for primary metabolites (amino acids, organic acids, carbohydrates, fatty acids) and volatile organic compounds (VOCs).
  • Data acquisition: Arduino and Raspberry Pi 3 boards, WELGROW cloud server (SQLite and MySQL databases).
  • Calibration: Gravimetric method (oven drying at 95 °C for 24 hours).
  • Field measurements: Weekly monitoring of flower cluster position, stem thickness, flowering degree, yield per plant, yield per fruit, cumulative yield.

Main Results

• The optimal 5 TE sensor placement for monitoring root-zone soil moisture in three-layered soil was determined to be at a 7.5 cm depth (manure layer).
• Tomato plants exhibited visible wilting when soil VWC dropped to 7.5%, with confirmed wilting at 5%.
• Physiological responses (transpiration rate, stomatal conductance) significantly declined when VWC decreased to 25%, while photosynthesis rate remained stable until 15% VWC.
• Volatile organic compounds (VOCs), specifically caryophyllene and β-phellandrene, doubled in emission as VWC decreased from 25% to 15%, serving as early stress signals.
• Primary metabolites (e.g., proline, GABA, malic acid, citric acid, fructose, glucose) accumulated significantly when VWC dropped to 7.5%.
• Maintaining VWC between 15% and 25% was identified as the optimal water-saving range, enhancing efficient tomato cultivation without negative effects on plant growth or visible stress symptoms.
• Field validation confirmed that this strategy resulted in high irrigation water use efficiency (IWUE) (>60 kg/m³), more than double previous reports (30 kg/m³), under two different irrigation management methods (based on accumulated solar radiation and accumulated evapotranspiration).

Contributions

• Uniquely combines real-time soil moisture monitoring with comprehensive morpho-physiological and biochemical analyses to optimize irrigation in three-layered soil systems.
• Identifies specific VWC thresholds at which distinct plant stress responses (physiological changes, VOC emissions, primary metabolite accumulation, visible wilting) are initiated.
• Establishes an optimal VWC range (15%–25%) for tomato cultivation in three-layered soil that significantly enhances irrigation water use efficiency (IWUE) while maintaining plant health and yield.
• Provides immediate practical strategies for addressing agricultural challenges under water-deficit conditions, particularly for sustainable crop productivity improvement.

Funding

• Intramural Grant (2Z07261) from the Korea Institute of Science and Technology (KIST).

Citation

@article{Cho2025Enhancing,
  author = {Cho, Jwa Yeong and Ryu, Da Hye and Jung, Dae-Hyun and Hamayun, Muhammad and Lee, Taek Sung and Park, Soo Hyun and Kim, Hye Min and Kim, Ho‐Youn and Kim, Ho-Youn and Kim, Ho-Youn},
  title = {Enhancing production efficiency of tomatoes through soil moisture–dependent multifaceted responses in three-layered soil},
  journal = {Plant Physiology and Biochemistry},
  year = {2025},
  doi = {10.1016/j.plaphy.2025.110443},
  url = {https://doi.org/10.1016/j.plaphy.2025.110443}
}