Organic Fertilization and Biostimulant Application to Improve Yield and Quality of Eggplant While Reducing the Environmental Impact
Abstract
1. Introduction
2. Results
2.1. Plant Growth and Fruit Production
2.2. Eggplant Fruit Quality
2.2.1. Color Parameters
2.2.2. Antioxidant Activity and Main Nutraceutical Compounds
3. Discussion
4. Materials and Methods
4.1. Plant Material, Growth Condition, and Experimental Treatments
4.2. Biometric Measurements, Leaf Greenness, and Fruit Yield
4.3. Qualitative Traits
4.3.1. Color Parameters and Firmness
4.3.2. Nitrogen and Carotenoid Content
4.3.3. Ascorbic Acid and Total Phenol Content, and Antioxidant Activity
4.4. Statistical Analysis
5. Conclusions
Author Contributions
Funding
Data Availability Statement
Acknowledgments
Conflicts of Interest
References
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Treatments | Early Marketable Yield | Total Marketable Fruits | DM | Firmness | N-Kjeldahl | ||
---|---|---|---|---|---|---|---|
n° m−2 | g fruit−1 | n° m−2 | g fruit−1 | % | kg cm−2 | % | |
Fertilization | |||||||
COM | 7.8 ± 0.7 b | 199.5 ± 3.9 b | 25.5 ± 1.3 b | 186.2 ± 4.7 b | 6.53 ± 0.1 b | 1.89 ± 0.02 | 1.92 ± 0.04 b |
DIG | 9.5 ± 0.7 a | 213.5 ± 3.8 a | 25.9 ± 1.2 b | 193.4 ± 2.3 ab | 6.87 ± 0.1 ab | 1.89 ± 0.02 | 2.08 ± 0.02 a |
MIN | 5.3 ± 0.3 c | 213.5 ± 6.8 a | 27.4 ± 1.1 a | 198.7 ± 2.6 a | 7.14 ± 0.1 a | 1.90 ± 0.02 | 1.98 ± 0.07 ab |
Biostimulant | |||||||
CTR | 6.0 ± 0.6 b | 200.3 ± 4.8 b | 22.2 ± 0.7 b | 189.3 ± 1.9 | 6.73 ± 0.15 | 1.84 ± 0.01 b | 1.95 ± 0.05 |
BIO | 8.1 ± 0.6 a | 208.9 ± 5.9 ab | 27.7 ± 0.6 a | 193.3 ± 2.6 | 6.91 ± 0.12 | 1.90 ± 0.01 ab | 2.01 ± 0.04 |
MIC | 8.5 ± 0.9 a | 217.3 ± 4.1 a | 28.8 ± 0.8 a | 195.7 ± 2.5 | 6.91 ± 0.11 | 1.94 ± 0.02 a | 2.02 ± 0.05 |
Significance | |||||||
Fertilization (F) | ** | * | ** | * | ** | ns | * |
Biostimulant (B) | ** | * | ** | ns | ns | ** | ns |
F × B | ns | ns | ns | ns | ns | ns | ns |
Treatments | L* | a* | b* |
---|---|---|---|
Fertilization | |||
COM | 25.7 ± 0.31 | 7.21 ± 0.58 | 0.96 ± 0.17 ab |
DIG | 26.3 ± 0.44 | 7.38 ± 0.40 | 1.07 ± 0.32 a |
MIN | 25.7 ± 0.18 | 7.22 ± 0.45 | 0.60 ± 0.09 b |
Biostimulant | |||
CTR | 26.5 ± 0.46 | 8.26 ± 0.36 a | 1.40 ± 0.28 a |
BIO | 25.5 ± 0.22 | 6.31 ± 0.23 b | 0.51 ± 0.10 b |
MIC | 25.7 ± 0.17 | 7.24 ± 0.53 ab | 0.71 ± 0.10 b |
Significance | |||
Fertilization (F) | ns | ns | * |
Biostimulant (B) | ns | * | ** |
F × B | ns | ns | ns |
Treatments | Carotenoids | AsA | Phenols | HAA | ABTS |
---|---|---|---|---|---|
µg g−1 fw | mg g−1 fw | mg Gallic Acid g−1 dw | mmol AA 100 g−1 dw | mmol Trolox 100 g−1 dw | |
Fertilization | |||||
COM | 0.017 ± 0.001 | 45.42 ± 5.45 a | 2.80 ± 0.09 | 5.26 ± 0.35 ab | 12.87 ± 0.51 |
DIG | 0.019 ± 0.001 | 32.82 ± 5.06 ab | 2.44 ± 0.16 | 5.71 ± 0.28 a | 13.11 ± 0.65 |
MIN | 0.020 ± 0.002 | 29.15 ± 3.61 b | 2.73 ± 0.17 | 4.88 ± 0.14 b | 12.47 ± 0.80 |
Biostimulant | |||||
CTR | 0.016 ± 0.001 b | 36.87 ± 4.77 | 2.62 ± 0.08 ab | 5.38 ± 0.32 | 12.81 ± 0.69 ab |
BIO | 0.018 ± 0.001 ab | 37.44 ± 5.46 | 2.46 ± 0.17 b | 5.25 ± 0.26 | 12.11 ± 0.58 b |
MIC | 0.022 ± 0.002 a | 33.08 ± 5.72 | 2.89 ± 0.16 a | 5.22 ± 0.30 | 13.53 ± 0.65 a |
Significance | |||||
Fertilization (F) | ns | * | ns | * | ns |
Biostimulant (B) | * | ns | * | ns | * |
F × B | ns | ns | ns | ns | ns |
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Duri, L.G.; Paradiso, R.; Di Mola, I.; Cozzolino, E.; Ottaiano, L.; Marra, R.; Mori, M. Organic Fertilization and Biostimulant Application to Improve Yield and Quality of Eggplant While Reducing the Environmental Impact. Plants 2025, 14, 962. https://doi.org/10.3390/plants14060962
Duri LG, Paradiso R, Di Mola I, Cozzolino E, Ottaiano L, Marra R, Mori M. Organic Fertilization and Biostimulant Application to Improve Yield and Quality of Eggplant While Reducing the Environmental Impact. Plants. 2025; 14(6):962. https://doi.org/10.3390/plants14060962
Chicago/Turabian StyleDuri, Luigi Giuseppe, Roberta Paradiso, Ida Di Mola, Eugenio Cozzolino, Lucia Ottaiano, Roberta Marra, and Mauro Mori. 2025. "Organic Fertilization and Biostimulant Application to Improve Yield and Quality of Eggplant While Reducing the Environmental Impact" Plants 14, no. 6: 962. https://doi.org/10.3390/plants14060962
APA StyleDuri, L. G., Paradiso, R., Di Mola, I., Cozzolino, E., Ottaiano, L., Marra, R., & Mori, M. (2025). Organic Fertilization and Biostimulant Application to Improve Yield and Quality of Eggplant While Reducing the Environmental Impact. Plants, 14(6), 962. https://doi.org/10.3390/plants14060962