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Plant Science Today (PST)

Research Articles

Vol. 12 No. 4 (2025)

Effect of zinc and potassium humate spraying on growth and yield of tomato (Solanum lycopersicum L.)

DOI
https://doi.org/10.14719/pst.11104
Submitted
4 August 2025
Published
08-10-2025 — Updated on 20-10-2025
Versions

Abstract

This study was carried out in a greenhouse associated to the College of Technical Agriculture in Al-Musayyab (32°36′59″ N, 44°22′25″ E) during the 2024-2025 growing season. The objective was to assess how commercial potassium humate fertilizer (PowHumus WSG 85) at five levels (0, 10, 15, 20 and 25 mL L-1) and zinc spray at three levels (0, 10 and 20 g L-1) interacted to enhance S. lycopersicum L. plant growth and productivity. The experiment was laid out in a randomized complete block design (RCBD) with three repetitions, using a drip irrigation system. Seedlings (40 days old) were transplanted at 40 cm spacing. Two foliar spraying were applied: the first 20 days after transplanting and the second, 20 days later. Measurements included: plant height, total number of leaves, number of flower cluster, number of flowers, number of fruits, fruit weight and total yield per plant. The best results were obtained by the combination with the maximum concentration of potassium humate (25 mL L-1) and zinc (20 g L-1), which produced notable changes. The following values were attained: 36.3 leaves, 8.03 panicles, 67.2 flowers, 23.8 fruits, 83.4 g of fruit weight, 84.2 cm of plant height and 1984.9 gm plant-1 for total yield. Based on these results, it is possible to enhance the vegetative growth, flowering and production of tomatoes cultivated in protected environments by utilizing the combination of zinc and potassium humate. Future studies across varieties and environments are recommended to validate these results and assess economic feasibility before large-scale adoption in sustainable fertilization programs.

References

  1. 1. Nelson DL, Lehninger AL, Cox MM. Lehninger Principles of Biochemistry. 8th ed. New York: W. H. Freeman and Company. 2021.
  2. 2. Salih AHSRH, Hussain MH, Hassoon AS. Antibacterial activity of Italic leaves aqueous extract against two pathogenic bacteria. Ann Trop Med Public Health. 2020;23:171–5. https://doi.org/10.36295/ASRO.2020.23123
  3. 3. Hamid MQ. Mycorrhiza and Trichoderma fungi role in improving soil physical properties planted with maize (Zea mays L.). SABRAO J Breed Genet. 2025;57(1):260–9. https://doi.org/10.54910/sabrao2025.57.1.25
  4. 4. Arshad I, Ali W. Effect of foliar application of zinc on growth and yield of guava (Psidium guajava L.). Adv Sci Technol Eng Syst J. 2016;1(1):19–22. https://doi.org/10.25046/aj010103
  5. 5. Al Hasnawi RA, AlJanaby ZAA, Jaafer AA, Mohammed RJ. Effect of nitrogen fertilization and irrigation water quality on some soil characteristics, growth and yield of sunflower. Plant Arch. 2020;20(1):2703–5.
  6. 6. Hamid MQ. Response of physical properties of sandy soil treated with different levels of natural soil conditioners zeolite and perlite. Sarhad J Agric. 2025;41(2):591–9. https://doi.org/10.17582/journal.sja/2025/41.2.591.599
  7. 7. Mohammed RJ, Abdulkadhim KA, Hassan DF, Kadhim TF. Effect of wheat straw as organic matter and different water quality on some chemical soil properties and growth of pepper (Capsicum annuum). IOP Conf Ser Earth Environ Sci. 2019;344(1):012034. https://doi.org/10.1088/1755-1315/344/1/012034
  8. 8. Hassan DF, Ati AS, Neima AS. Effect of irrigation uniformity and efficiency on water consumption, yield of maize using different irrigation and cultivation methods. Int J Agric Stat Sci. 2021;17(1):1441–50.
  9. 9. Abdullah AA, Al-Saadi MMK. Effect of different levels of potassium humate and agricultural sulfur on some growth indicators and yield of hybrid tomato “Hatouf” in desert areas of southern Iraq. Kufa J Agric Sci. 2016;8(1):48–66.
  10. 10. Hassoon AS, Ussain MH, Harby HH. Effect of spraying of humic acid on sepals extract content from some antioxidants for three varieties of rosella (Hibiscus sabdariffa L.). Plant Arch. 2018;18(1):1129–33.
  11. 11. Akol AM, Hassan DF, Mohammed RJ, Al Janaby ZAA, Kadium Abed MA, Hussain S, et al. Optimizing wheat yield and water use efficiency using AquaCrop model calibration and validation in various irrigation and tillage systems under climate change. Soil Sci Annu. 2024;75(3). https://doi.org/10.37501/soilsa/195823
  12. 12. Hussain MH, Al Myali AAH, Hassoon AS. Effect of cyanobacteria as a biofertilizer on qualitative and quantitative characteristics of tomato varieties. Biochem Cell Arch. 2019;19(2):4083–6.
  13. 13. Hussain MH, Hassoon AS. Direct measurement of fatty acid composition of sunflower and variation of the fatty acids distribution with different treatments of fertilizer using HPLC technique. Res Crops. 2018;19(3):414–8. https://doi.org/10.31830/2348-7542.2018.0001.9
  14. 14. Hundi HK, Hamid MQ, Noori AAM. Role of Ochrobactrum bacteria and organic matter in pant growth and the content of N, P and K under soil salinity stress. J Environ Earth Sci. 2025;7(5):130–9. https://doi.org/10.30564/jees.v7i5.8777
  15. 15. Drebee HA, Razak NAA, Shaybth RT. Understanding the causes of the decline in the Iraqi agricultural sector’s contribution to the GDP. IOP Conf Ser Earth Environ Sci. 2022;1060(1):012146. https://doi.org/10.1088/1755-1315/1060/1/012146
  16. 16. Al-Muhammadi FMH. Protected agriculture. Baghdad: University of Baghdad, Ministry of Higher Education and Scientific Research. 1992.
  17. 17. Page AL, editor. Methods of soil analysis. Part 2: Chemical and microbial properties. Madison (WI): American Society of Agronomy, Soil Science Society of America. 1982. https://doi.org/10.2134/agronmonogr9.2.2ed
  18. 18. Lindsay WL, Norvell WA. Development of a DTPA soil test for zinc, iron, manganese and copper. Soil Sci Soc Am J. 1978;42:421–8. https://doi.org/10.2136/sssaj1978.03615995004200030009x
  19. 19. Al-Rawi KM, Khalaf Allah AM. Design and analysis of agricultural experiments. Mosul: Dar Al-Kutub, University of Mosul. 2000.
  20. 20. Esfandiari E, Abdoli M, Mousavi S. Impact of foliar zinc application on agronomic traits and grain quality parameters of wheat grown in zinc deficient soil. Indian J Plant Physiol. 2016;21(3):263–70. https://doi.org/10.1007/s40502-016-0225-4
  21. 21. Hamid MQ, Abd EH, Al-Salihi ZK, Muhammed RJ, Hassan DF. Effect of organic conditioners on the physical properties of sandy soil under drip irrigation conditions. Sarhad J Agric. 2025;41(3):1133–42. https://doi.org/10.17582/journal.sja/2025/41.3.1133.1142
  22. 22. Drebee HA, Abdul Razak NA, Mohsen AA. Maize production forecasting in Iraq: A Box-Jenkins approach for the period of 2022–2026. IOP Conf Ser Earth Environ Sci. 2023;1259(1):012128. https://doi.org/10.1088/1755-1315/1259/1/012128
  23. 23. Mengel K, Kirkby EA. Principles of plant nutrition. 4th ed. Bern, Switzerland: International Potash Institute. 1987.
  24. 24. Al-Saadi MMK. Effect of potassium humate foliar application on growth and yield of tomato (Lycopersicon esculentum Mill.). Kufa J Agric Sci. 2012;4(2):41–50.
  25. 25. Hamza MM, Salman HA, Obeid OH. Effect of spraying frequency and level of humus soil fertilizer on the growth and yield of cucumber (Cucumis sativus) grown in a glasshouse. Al-Furat J Agric Sci. 2009;2(1):87–98.

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