Physiological Effects of the Brown Seaweed (Ascophyllum nodosum) and Humic Substances on Plant Growth, Enzyme Activities of Certain Pepper Plants Grown under Salt Stress


This study was aimed to examine the effects of seaweed extract (SW) and humic acid on the fruit yield, dry weight (DW%), protein, proline, lipid peroxidation (LPO) and antioxidative enzyme activity of pepper plants (Capsicum annuum L.) grown under saline conditions (100 mM). The obtained results indicated that salinity stress affected deleteriously plant growth and all other parameters. Besides, the treatment of seaweed (SW) and humic acid (HA) improved vegetative growth in the plant at all concentration levels applied under salinity conditions. Leaf fresh and dry weight was increased by all SW and HA applications in salinity stressed plant compared to those of control. Furthermore, there was a significant improvement in antioxidant enzyme activity, such as superoxide dismutase (SOD), peroxidase (POD), catalase (CAT) activities in the plant under salt stress and treated with SW and HA compounds. It suggests that seaweed and humic acid can enhance salt stress tolerance and leads to conservation of pepper plant against oxidative stress.


  1. 1.

    Arthur, G. D., Stirk, W. A., Van Staden, J. (2003) Effect of a seaweed concentrate on the growth and yield of three varieties of Capsicum annuum. S. Afr. J. Chem. 69, 207–211.

    Google Scholar 

  2. 2.

    Ashraf, M., Harris, P. J. C. (2004) Potential biochemical indicators of salinity tolerance in plants. Plant Sci. 166, 3–16.

    CAS  Google Scholar 

  3. 3.

    Ashraf, M., Foolad, M. R. (2007) Roles of glycine betaine and proline in improving plant abiotic stress resistance. Environ. Exper. Bot. 59, 206–216.

    CAS  Google Scholar 

  4. 4.

    Ashrafuzzaman, M., Khan, M. A. H., Shahidullah, S. M. (2003) Response of vegetative growth of maize (Zea mays) to a range of salinity. J. Biol. Sci. 3, 253–258.

    Google Scholar 

  5. 5.

    Aymen, E. M., Salma, L., Halima, C., Cherif, H., Mimoun. E. (2014) Effect of seaweed extract of Sargassum vulgare on germination behavior of two tomatoes cultivars (Solanum Lycopersıcum L.) under salt stress. Oct. Jour. Env. Res. 2, 203–210.

    Google Scholar 

  6. 6.

    Bates, L. S., Waldren, R. P., Teare, I. D. (1973) Rapid determination of free proline for water stress studies. Plant Soil 39, 205–207.

    CAS  Google Scholar 

  7. 7.

    Battacharyya, D., Babgohari, M. Z., Rathor, P., Prithiviraj, B. (2015) Seaweed extracts as biostimulants in horticulture. Sci. Hortic. 196, 39–48.

    CAS  Google Scholar 

  8. 8.

    Bergmeyer, N. (1970) Methoden Der Enzymatischen Analyse. Berlin: Akademie Verlag, 1: pp. 636–647.

    Google Scholar 

  9. 9.

    Bradford, M. M. (1976) A rapid and sensitive method for the quantitation of micrograms quantities of protein utilizing the principle of Protein-Dye Binding. Anal. Biochem. 72, 248–254.

    CAS  Google Scholar 

  10. 10.

    Cakmak, I., Horst, W. J. (1991) Effect of aluminum on lipid peroxidation, superoxide dismutase, catalase, and peroxidase activities in root tips of soybean (Glycine max). Physiol. Plant. 83, 463–468.

    CAS  Google Scholar 

  11. 11.

    Cakmak, I., Strbac, D., Marschner, H. (1993) Activities of hydrogen peroxide-scavenging enzymes in germinating wheat seeds. J. Exp. Bot. 44, 127–132.

    CAS  Google Scholar 

  12. 12.

    Canellas, L. P., Olivares, F. L., Aguiar, N. O., Jones, D. L., Nebbioso, A., Mazzei, P., Piccolo, A. (2015) Humic and fulvic acids as biostimulants in horticulture. Sci. Hortic. 196, 15–27.

    CAS  Google Scholar 

  13. 13.

    Chbania, A., Majed, S., Mawlawi, H., Kammoun, M. (2015) The use of seaweed as a bio-fertilizer: Does it influence proline and chlorophyll concentration in plants treated? AJMAP 1, 67–77.

    Google Scholar 

  14. 14.

    Chen, Y., Aviad, T. (1990) Effects of humic substances on plant growth. In: MacCarthy, P., Clapp, C. E., Malcolm, R. L., Bloom, P. R. (eds), Humic Substances in Soil and Crop Sciences: Selected Readings. SSSA, Madison, pp. 161–186.

    Google Scholar 

  15. 15.

    Clapp, C. E., Liu, R., Cline, V. W., Chen, Y., Hayes, M. H. B. (1998) Humic substances for enhancing turfgrass growth. In: Davies, G., Gabbour, E. A. (eds) Humic substances: Structures, properties, and uses. Royal Society of Chemistry Publ. Cambridge, U.K. pp. 227–234.

    Google Scholar 

  16. 16.

    Esringü, A., Kaynar, D., Turan, M., Ercişli, S. (2016) Ameliorative effect of humic acid and plant growth-promoting rhizobacteria (PGPR) on Hungarian vetch plants under salinity stress. Commun. Soil Sci. Plant Anal. 47, 602–618.

    Google Scholar 

  17. 17.

    Fan, D., Hodges, D. M., Critchley, A. T., Prithiviraj, B. (2013) A commercial extract of brown macroalga (Ascophyllum nodosum) affects yield and the nutritional quality of spinach in vitro. Commun. Soil Sci. Plant Anal. 44, 1873–1884.

    CAS  Google Scholar 

  18. 18.

    Farahat, M. M., Mazhar, A. A., Mona, H., Mahgoub, M. H. (2012) Response of Khaya senegalensis seedlings to irrigation intervals and foliar application of humic acid. JHSOP 4, 292–298.

    CAS  Google Scholar 

  19. 19.

    Fornes, F., Sánchez-Perales, M., Guadiola, J. L. (2002) Effect of a seaweed extract on the productivity of ‘de Nules’ Clementine mandarin and navelina orange. Bot. Mar. 45, 486–489.

    Google Scholar 

  20. 20.

    Gharib, F. A. E. L., Zeid, İ. M., Salem, O. M. A. E. H., Ahmed, E. Z. (2014) Effects of Sargassum latifolium extract on growth, oil content and enzymatic activities of rosemary plants under salinity stress. Life Sci. 11, 933–945.

    Google Scholar 

  21. 21.

    Giannopolitis, C. N., Ries, S. K. (1977) Superoxide dismutases occurrence in higher plants. Plant Physiol. 59, 309–314.

    CAS  PubMed  PubMed Central  Google Scholar 

  22. 22.

    Haddadi, B. S., Hassanpour, H., Niknam, V. (2016) Effect of salinity and waterlogging on growth, anatomical and antioxidative responses in Mentha aquatica L. Acta Physiol. Plant 38, 119.

    Google Scholar 

  23. 23.

    Hayat, S., Hayat, Q., Alyemeni, M. N., Wani, A. S., Pichtel, J., Ahmad, A. (2012) Role of proline under changing environments: a review. Plant Signal. Behav. 7, 1456–1466.

    CAS  PubMed  PubMed Central  Google Scholar 

  24. 24.

    Henderson, J. (2004) The Roman book of gardening. Routledge, London.

    Google Scholar 

  25. 25.

    Herzog V., Fahimi, H. (1973) Determination of the activity of peroxidase. Anal. Biochem. 55, 554–562.

    CAS  PubMed  Google Scholar 

  26. 26.

    Karthikeyan, K., Shanmugam, M. (2014) Enhanced yield and quality in some banana varieties applied with commercially manufactured biostimulant Aquasap from sea plant Kappaphycus alvarezii. J. Agr. Sci. Tech. B 4, 621–631.

    Google Scholar 

  27. 27.

    Khan, W., Rayirath, U. P., Subramanian, S., Jithesh, M. N., Rayorath, P., Hodges, D. M., Critchley, A. T., Craigie, J. S., Norrie, J., Prithiviraj, B. (2009) Seaweed extracts as biostimulants of plant growth and development. J. Plant Growth Regul. 28, 386–399.

    CAS  Google Scholar 

  28. 28.

    Latique, S., Chernane, H., Mansori, M., El Kaoua, M. (2016) Biochemical modification and changes in antioxidant enzymes in Triticum durum L. by seaweed liquid extract of Ulva rigida macroalgae under salt stress condition. Adv. Environ. Res. 50, 35–54.

    Google Scholar 

  29. 29.

    Li, W., Liu, X., Khan, M. A., Yamagnchi, S. (2005) The effect of plant growth regulators, nitric oxide, nitrate, nitrite and light on the germination of dimorphic seeds of Suaeda salsa under saline conditions. J. Plant Res. 118, 207–214.

    CAS  PubMed  Google Scholar 

  30. 30.

    Liang, Z., Sun, X., Wang, F., Wang, W., Liu, F. (2013) Impact of environmental factors on the photosynthesis and respiration of young seedlings of Sargassum thunbergii (Sargassaceae, Phaeophyta). Am. J. Plant Sci. 4, 27–33.

    Google Scholar 

  31. 31.

    Manaf, H. H. (2016) Beneficial effects of exogenous selenium, glycine betaine and seaweed extract on salt stressed cowpea plant. Ann. Agric. Sci. 61, 41–48.

    Google Scholar 

  32. 32.

    Nakano, Y., Asada, Y. (1987) Purification of ascorbate peroxidase from spinach chloroplasts: Its inactivation in ascorbate depleted medium and reactivation by monodehydroascorbate radical. Plant Cell Physiol. 28, 131–140.

    CAS  Google Scholar 

  33. 33.

    Osman, A. S., Rady, M. M. (2012) Ameliorative effects of sulfur and humic acid on the growth, antioxidant levels, and yields of pea (Pisum sativum L.) plants grown in reclaimed saline soil. J. Hortic. Sci. Biotechnol. 87, 626–632.

    CAS  Google Scholar 

  34. 34.

    Popescu, G. C., Popescu, M. (2014) Effect of the brown alga Ascophyllum nodosum as biofertilizer on vegetative growth in grapevine (Vitis vinifera L.). CTNS 3, 61–67.

    Google Scholar 

  35. 35.

    Rathore, S. S., Chaudhary, D. R., Boricha, G. N., Ghosh, A., Bhatt, B. P., Zodape, S. T., Patolia, J. S. (2009) Effect of seaweed extract on the growth, yield and nutrient uptake of soybean (Glycine max) under rainfed conditions. S. Afr. J. Bot. 75, 351–355.

    CAS  Google Scholar 

  36. 36.

    Shah, M. T., Zodape, S. T., Chaudhary, D. R., Eswaran, K., Chikara, J. (2013) Seaweed sap as an alternative liquid fertilizer for yield and quality improvement of wheat. J. Plant Nutr. 36, 192–200.

    CAS  Google Scholar 

  37. 37.

    Sylvia, S., Baluswami, M., Parthasarathy, V. M. D., Krishnamurthy, V. (2005) Effect of liquid seaweed fertilizers extracted from Gracilaria edulis (Gmel.) Silva, Sargassum wightii greville and Ulva lactuca Linn. on the growth and yield of Abelmoschus esculentus (L.) Moench. Indian Hydrobiol. 7, 69–88.

    Google Scholar 

  38. 38.

    Temple, W. D., Bomke, A. A. (1989) Effects of kelp (Macrocystis integrifolia and Ecklonia maxima) foliar application on bean crop growth. Plant Soil 117, 85–92.

    Google Scholar 

  39. 39.

    Wang, Y., Xiang, L., Wang, S., Wang, X., Chen, X., Mao, Z. (2017) Effects of seaweed fertilizer on the Malus hupehensis Rehd. seedlings growth and soil microbial numbers under continuous cropping. Acta Ecol. Sin. 37, 180–186.

    Google Scholar 

  40. 40.

    Weisany, W., Sohrabi, Y., Heidari, G., Siosemardeh, A., Golezani, K. G. (2012) Changes in antioxidant enzymes activity and plant performance by salinity stress and zinc application in soybean (Glycine max L.). Plant Omics. 5, 60–67.

    CAS  Google Scholar 

  41. 41.

    Xu, C., Leskovar, D. I. (2015) Effects of Ascophyllum nodosum seaweed extracts on spinach growth, physiology and nutrition value under drought stress. Sci. Hort. 183, 39–47.

    Google Scholar 

  42. 42.

    Yıldıztekin, M., Kaya, C., Tuna, A. L., Ashraf, M. (2015) Oxidative stress and antioxidative mechanisms in tomato (Solanum lycopersicum L.) plants sprayed with different pesticides. Pak. J. Bot. 47, 717–721.

    Google Scholar 

  43. 43.

    Yildiz, M., Terzi, H. (2013) Effect of NaCl stress on chlorophyll biosynthesis, proline, lipid peroxidation and antioxidative enzymes in leaves of salt-tolerant and salt-sensitive barley cultivars. JAS 19, 79–88.

    Google Scholar 

  44. 44.

    Zodape, S. T., Mukhopadhyay, S., Eswaran, K., Reddy, M. P., Chikara, J. (2010) Enhanced yield, and nutritional quality in green gram (Phaseolus radiata L) treated with seaweed (Kappaphycus alvarezii) extract. JSIR 69, 468–471.

    CAS  Google Scholar 

  45. 45.

    Zou, X. X., Xing, S. S., Su, X., Zhu, J., Huang, H. Q., Bao, S. X. (2017) The effects of temperature, salinity, and irradiance upon the growth of Sargassum polycystum C. Agardh (Phaeophyceae). J. Appl. Phycol. 29, 1–9.

    Google Scholar 

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Correspondence to Mahmut Yildiztekin.

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Yildiztekin, M., Tuna, A.L. & Kaya, C. Physiological Effects of the Brown Seaweed (Ascophyllum nodosum) and Humic Substances on Plant Growth, Enzyme Activities of Certain Pepper Plants Grown under Salt Stress. BIOLOGIA FUTURA 69, 325–335 (2018).

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Key words

  • Capsicum annuum L.
  • salt stress
  • antioxidative enzymes
  • seaweed
  • humic acid