Mercury toxicity affects oxidative metabolism and induces stress responsive mechanisms in wheat (Triticum aestivum L.).

İşkil R., Surgun Acar Y., Çatav Ş. S., Zemheri F., Erden Y.

PHYSIOLOGY AND MOLECULAR BIOLOGY OF PLANTS, vol.1, pp.1-10, 2022 (SCI-Expanded)

  • Publication Type: Article / Article
  • Volume: 1
  • Publication Date: 2022
  • Doi Number: 10.1007/s12298-022-01171-x
  • Journal Name: PHYSIOLOGY AND MOLECULAR BIOLOGY OF PLANTS
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Agricultural & Environmental Science Database, Aquatic Science & Fisheries Abstracts (ASFA), BIOSIS, Biotechnology Research Abstracts, CAB Abstracts, Veterinary Science Database
  • Page Numbers: pp.1-10
  • Çanakkale Onsekiz Mart University Affiliated: Yes

Abstract

Mercury (Hg) toxicity is an increasing problem worldwide, with a negative impact on the environment and living organisms including both animals and plants. In this study, we analyzed molecular and biochemical changes related to Hg toxicity in wheat (Triticum aestivum L.) seedlings. Seven-day-old seedlings were exposed to various concentrations (5, 10, and 20 lM) of HgCl2 for 24 and 48 h. Our results showed that HgCl2 treatments led to an increase in the Hg content of wheat leaves in a time- and concentration-dependent manner. Furthermore, significant increases were observed in hydrogen peroxide, malondialdehyde, and proline contents in response to Hg toxicity. While all HgCl2 treatments decreased the level of superoxide dismutase (SOD), the level of catalase (CAT) was reduced only in seedlings exposed to 5 lM of HgCl2. Mercury stress caused a decline in the expression of Cu/ZnSOD, Fe-SOD, TaWRKY19, and TaDREB1 genes at both exposure times. On the other hand, 10 and 20 lM HgCl2 treatments caused significant induction (1.9 to 6.1-fold) in the expression of the CAT gene in wheat leaves. The mRNA level of the Mn-SOD and TaWRKY2 genes showed different patterns depending on the concentration and exposure period of HgCl2. In conclusion, the findings of this work demonstrate that Hg toxicity causes oxidative damage in wheat seedlings and changes the expression of some genes encoding WRKY and DREB transcription factor families, which have important functions in abiotic stress response.