The Effect of Humic Acid on Plant Growth, Phytoremediation and Oxidative Stress in Rapeseed (Brassica napus L.) Grown Under Heavy Metal Stress


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Boysan Canal S., Bozkurt M. A. , Yılmaz H.

Yüzüncü Yıl Üniversitesi Ziraat Fakültesi Tarım Bilimleri Dergisi, vol.32, no.2, pp.237-248, 2022 (Peer-Reviewed Journal)

  • Publication Type: Article / Article
  • Volume: 32 Issue: 2
  • Publication Date: 2022
  • Journal Name: Yüzüncü Yıl Üniversitesi Ziraat Fakültesi Tarım Bilimleri Dergisi
  • Journal Indexes: TR DİZİN (ULAKBİM)
  • Page Numbers: pp.237-248

Abstract

The aim of this study was to investigate the effects of humic acid (HA) applications on rapeseed (Brassica napus L.) growth, heavy metal uptake, bioconcentration factor (BCF), translocation factor (TF), tolerance index (TI), catalase (CAT), ascorbate peroxidase (APX) enzyme activities and hydrogen peroxide (H2O2) content in polluted soil with lead (Pb) 100 mg kg-1, chromium (Cr) 100 mg kg-1, cadmium (Cd) 100 mg kg-1, and zinc (Zn) 250 mg kg-1. Three doses of HA (HA1:500 mg kg-1, HA2:1000 mg kg-1, HA3:2000 mg kg-1) were applied in heavy metal-treated pots. HA1, HA2 and HA3 applications increased plant growth compared to soil polluted with heavy metals. In comparison to the control, increased amounts of Pb, Cr, Cd, and Zn contents were detected in the roots and shoots of the rapeseed plant in polluted soil. HA applications in polluted soil importantly decreased the heavy metal content in the roots and shoots of the plant. BCF in both roots and shoots of the plants were greater than 1 for Pb, Cr, Cd, and Zn in polluted soils. However, specifically HA2 application decreased the shoot and root BCF values in polluted soil. TF was smaller than 1 in Pb, Cr, Cd, and Zn in polluted soil. On the other hand, HA applications in Cd polluted soil increased TF values. Shoot TI decreased by 17.37 % and root TI decreased by 9.09% in polluted soil. CAT and APX enzyme activities and H2O2 increased significantly in the heavy metal polluted soil. However, HA applications decreased CAT and APX enzyme activities and H2O2 content in rapeseed. It is concluded that HA application in Pb, Cr, Cd and Zn contaminated soil has a remedial effect on the development of rapeseed through reducing heavy metal content and oxidative stress.