Visible and Near-Infrared Spectroscopy for Investigation of Water and Nitrogen Stress in Tomato Plants
Abstract
:1. Introduction
- Investigate changes in the water structure of control and stressed plants using an aquaphotomic approach;
- Test different vegetative indices for detecting water and nitrogen stress in tomato plants;
- Create models for the classification of control and stressed tomato plants based on their near-infrared spectra.
2. Materials and Methods
2.1. Tomato Experiment
2.2. Spectral Measurement
2.3. Vegetative Indices
2.4. Data Analysis, Classification Models, and Aquagrams
3. Results and Discussion
3.1. Tomato Plants Spectra
3.2. Vegetative Indices Analysis
3.3. Models for Classification of Plants According to Stress Factors
4. Conclusions
Author Contributions
Funding
Data Availability Statement
Conflicts of Interest
References
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Index | Definition | Reference |
---|---|---|
CARI Chlorophyll Absorption in Reflectance Index | [22] | |
Cl green Green chlorophyll index | [23] | |
Cl red edge Chlorophyll Index at red edge | [23] | |
CLSI Cercospora leaf spot index | [24] | |
CRI Carotenoids Reflectance index | [25] | |
fD Index of disease | [26] | |
G Greenness index | [27] | |
HI Healthy index | [24] | |
MCARI Modified chlorophyll absorption in reflectance index | [28] | |
mNDVI Modified Normalized Difference Vegetation Index | [29] | |
NDVI (1) Normalized Difference Vegetation Index | [29] | |
NDVI (2) Normalized Difference Vegetation Index | [30] | |
NDVI (3) Normalized Difference Vegetation Index | [31] | |
PI Pigment index | [32] | |
PMI Powdery mildew index | [24] | |
PRI Photochemical reflectance index | [33] | |
PSRI Plant Senescence Reflectance Index | [34] | |
REI 1 Red Edge Index | [35] | |
REI 2 Red Edge Index | [35] | |
REI 3 Red Edge Index | [35] | |
SBRI Sugar beet rust index | [24] | |
SR Simple ratio | [36] | |
TVI Triangular vegetation index | [37] | |
WBI Water band index | [38] |
Vegetation Indices | Control (n = 66) | With Reduced Fertilization (n = 69) | With Reduced Watering (n = 66) | Sig. |
---|---|---|---|---|
CARI | 0.065 ± 0.009 a | 0.070 ± 0.010 ab | 0.062 ± 0.013 b | 0.001 |
Cl green | 4.363 ± 0.497 a | 4.027 ± 0.623 ab | 4.489 ± 0.522 b | 0.001 |
Cl red edge | 1.252 ± 0.108 a | 1.1787 ± 0.129 ab | 1.350 ± 0.217 ab | 0.001 |
CLSI | −0.471 ± 0.040 | −0.478 ± 0.059 | −0.489 ± 0.051 | 0.138 |
CRI | 11.705 ± 8.89 | 11.679 ± 9.77 | 12.386 ± 8.34 | 0.877 |
fD | 0.332 ± 0.148 | 0.333 ± 0.170 | 0.305 ± 0.140 | 0.477 |
G | 2.399 ± 0.285 | 2.460 ± 0.251 | 2.335 ± 0.286 | 0.033 |
HI | −0.023 ± 0.041 | −0.019 ± 0.057 | −0.018 ± 0.062 | 0.841 |
MCARI | 0.166 ± 0.047 | 0.180 ± 0.052 b | 0.153 ± 0.0636 b | 0.014 |
mNDVI | 0.567 ± 0.021 a | 0.550 ± 0.029 ab | 0.578 ± 0.040 ab | 0.001 |
NDVI (1) | 0.860 ± 0.023 | 0.856 ± 0.023 | 0.860 ± 0.020 | 0.336 |
NDVI (2) | 0.851 ± 0.022 | 0.845 ± 0.022 | 0.851 ± 0.019 | 0.176 |
NDVI (3) | 0.859 ± 0.022 | 0.854 ± 0.022 | 0.858 ± 0.020 | 0.364 |
PI | 0.423 ± 0.050 | 0.410 ± 0.039 b | 0.435 ± 0.052 b | 0.014 |
PMI | −0.373 ± 0.060 a | −0.373 ± 0.069 b | −0.401 ± 0.058 ab | 0.013 |
PRI | 0.047 ± 0.025 a | 0.051 ± 0.031 ab | 0.036 ± 0.020 b | 0.002 |
PSRI | −0.009 ± 0.049 | −0.017 ± 0.063 | 0.005 ± 0.047 | 0.051 |
REI1 | 1.558 ± 0.043 a | 1.531 ± 0.049 ab | 1.588 ± 0.076 ab | 0.001 |
REI2 | 1.115 ± 0.073 a | 1.079 ± 0.076 ab | 1.144 ± 0.104 b | 0.001 |
REI3 | 0.525 ± 0.028 a | 0.510 ± 0.030 ab | 0.537 ± 0.042 ab | 0.001 |
SBRI | 0.022 ± 0.058 | 0.019 ± 0.065 | 0.029 ± 0.055 | 0.634 |
SR | 8.114 ± 0.687 a | 7.694 ± 0.837 ab | 8.352 ± 0.937 b | 0.001 |
TVI | 34.046 ± 1.378 | 34.156 ± 2.041 | 34.377 ± 1.432 | 0.503 |
WBI | 1.224 ± 0.065 a | 1.223 ± 0.088 b | 1.180 ± 0.131 ab | 0.012 |
Vegetation Indices | Control (n = 66) | With Reduced Fertilization (n = 69) | With Reduced Watering (n = 66) | Sig. |
---|---|---|---|---|
CARI | 0.050 ± 0.009 a | 0.064 ± 0.011 a | 0.061 ± 0.010 a | 0.001 |
Clgreen | 4.704 ± 0.665 a | 4.328 ± 0.871 a | 4.482 ± 0.617 | 0.010 |
Clred edge | 1.410 ± 0.168 | 1.384 ± 0.182 | 1.376 ± 0.175 | 0.507 |
CLSI | −0.445 ± 0.033 a | −0.562 ± 0.131 ab | −0.523 ± 0.106 ab | 0.001 |
CRI | 11.705 ± 8.89 | 11.679 ± 9.77 | 12.386 ± 8.34 | 0.877 |
fD | 0.380 ± 0.118 | 0.385 ± 0.184 | 0.365 ± 0.156 | 0.754 |
G | 2.030 ± 0.233 a | 2.276 ± 0.278 a | 2.239 ± 0.296 a | 0.001 |
HI | −0.011 ± 0.035 a | 0.011 ± 0.056 ab | −0.008 ± 0.048 b | 0.015 |
MCARI | 0.107 ± 0.033 a | 0.141 ± 0.040 a | 0.140 ± 0.045 a | 0.001 |
mNDVI | 0.593 ± 0.030 | 0.586 ± 0.031 | 0.585 ± 0.02 | 0.245 |
NDVI (1) | 0.847 ± 0.024 | 0.852 ± 0.028 | 0.855 ± 0.025 | 0.162 |
NDVI (2) | 0.837 ± 0.023 | 0.841 ± 0.028 | 0.844 ± 0.024 | 0.276 |
NDVI (3) | 0.845 ± 0.024 | 0.849 ± 0.029 | 0.852 ± 0.025 | 0.290 |
PI | 0.499 ± 0.054 a | 0.446 ± 0.054 a | 0.454 ± 0.057 a | 0.001 |
PMI | −0.335 ± 0.056 a | −0.387 ± 0.038 a | −0.388 ± 0.037 a | 0.001 |
PRI | 0.046 ± 0.016 | 0.055 ± 0.030 | 0.048 ± 0.022 | 0.064 |
PSRI | −0.010 ± 0.041 a | −0.044 ± 0.083 ab | −0.020 ± 0.060 b | 0.006 |
REI1 | 1.621 ± 0.066 | 1.601 ± 0.068 | 1.599 ± 0.065 | 0.103 |
REI2 | 1.212 ± 0.114 a | 1.161 ± 0.104 a | 1.164 ± 0.111 a | 0.010 |
REI3 | 0.561 ± 0.043 a | 0.542 ± 0.040 a | 0.543 ± 0.042 a | 0.009 |
SBRI | 0.009 ± 0.051 | −0.009 ± 0.089 | 0.005 ± 0.071 | 0.326 |
SR | 8.287 ± 0.937 | 8.319 ± 0.970 | 8.328 ± 0.763 | 0.962 |
TVI | 31.556 ± 1.326 a | 38.187 ± 5.839 ab | 36.520 ± 4.834 ab | 0.001 |
WBI | 1.218 ± 0.040 a | 1.085 ± 0.188 a | 1.116 ± 0.156 a | 0.001 |
Manusa Variety—Statistically Significant Differences | Red Bounty Variety—Statistically Significant Differences | ||||||
---|---|---|---|---|---|---|---|
Vegetative Indices | Used Wavelengths | Control-Reduced N Fertilization | Control-Reduced Watering | Reduced N Fertilization—Reduced Watering | Control-Reduced N Fertilization | Control-Reduced Watering | Reduced N Fertilization—Reduced Watering |
CARI | 550, 670, 700 | v | v | o | o | ||
Clgreen | 550, 760 | v | v | o | |||
Clred edge | 714, 760 | v | v | v | |||
CLSI | 570, 698, 734 | o | o | o | |||
G | 554, 677 | o | o | ||||
HI | 534, 698, 704 | o | o | ||||
MCARI | 550, 670, 700 | v | o | o | |||
mNDVI | 705, 750 | v | v | v | |||
PI | 554, 677 | v | o | o | |||
PMI | 520, 584, 724 | v | v | o | o | ||
PRI | 531, 570 | v | v | ||||
PSRI | 500, 680, 750 | o | o | ||||
REI 1 | 720, 740 | v | v | v | |||
REI 2 | 715, 720, 734, 747 | v | v | o | o | ||
REI 3 | 715, 726, 734, 747 | v | v | v | o | o | |
SR | 695, 760 | v | v | ||||
TVI | 550, 670, 750 | o | o | o | |||
WBI | 900, 970 | v | v | o | o |
Determined as Control Plants | Determined as Plants with Reduced Nitrogen Fertilization | Determined as Plants with Reduced Watering | No Match | Sensitivity, % | F1 Score, % | |
---|---|---|---|---|---|---|
Control plants | 96 | 2 | 4 | 0 | 94.12 | 96.48 |
Plants grown with reduced nitrogen fertilization | 0 | 86 | 0 | 0 | 100.00 | 98.85 |
Plants grown with reduced watering | 1 | 0 | 84 | 2 | 96.55 | 95.95 |
Precision, % | 98.97 | 97.72 | 95.45 |
Determined as Control Plants | Determined as Plants with Reduced Nitrogen Fertilization | Determined as Plants with Reduced Watering | No Match | Sensitivity, % | F1 Score, % | |
---|---|---|---|---|---|---|
Control plants | 77 | 5 | 4 | 0 | 89.53 | 87.50 |
Plants grown with reduced nitrogen fertilization | 8 | 75 | 6 | 0 | 84.27 | 85.23 |
Plants grown with reduced watering | 5 | 7 | 80 | 0 | 86.95 | 87.91 |
Precision, % | 85.55 | 88.23 | 88.88 |
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Atanassova, S.; Petrova, A.; Yorgov, D.; Mineva, R.; Veleva, P. Visible and Near-Infrared Spectroscopy for Investigation of Water and Nitrogen Stress in Tomato Plants. AgriEngineering 2025, 7, 155. https://doi.org/10.3390/agriengineering7050155
Atanassova S, Petrova A, Yorgov D, Mineva R, Veleva P. Visible and Near-Infrared Spectroscopy for Investigation of Water and Nitrogen Stress in Tomato Plants. AgriEngineering. 2025; 7(5):155. https://doi.org/10.3390/agriengineering7050155
Chicago/Turabian StyleAtanassova, Stefka, Antoniya Petrova, Dimitar Yorgov, Roksana Mineva, and Petya Veleva. 2025. "Visible and Near-Infrared Spectroscopy for Investigation of Water and Nitrogen Stress in Tomato Plants" AgriEngineering 7, no. 5: 155. https://doi.org/10.3390/agriengineering7050155
APA StyleAtanassova, S., Petrova, A., Yorgov, D., Mineva, R., & Veleva, P. (2025). Visible and Near-Infrared Spectroscopy for Investigation of Water and Nitrogen Stress in Tomato Plants. AgriEngineering, 7(5), 155. https://doi.org/10.3390/agriengineering7050155