Abstract
In this study, we evaluated the leaf antioxidative responses of three wheat varieties (Srpanjka, Divana, and Simonida) treated with two different forms of zinc (Zn), Zn-sulfate and Zn-EDTA, in concentrations commonly used in agronomic biofortification. Zn concentration was significantly higher in the flag leaves of all three wheat varieties treated with Zn-EDTA compared to control and leaves treated with Zn-sulfate. Both forms of Zn increased malondialdehyde level and total phenolics content in varieties Srpanjka and Divana. Total glutathione content was not affected after the Zn treatment. Zn-sulfate increased the activities of glutathione reductase (GR) and guaiacol peroxidase (GPOD) in both Srpanjka and Divana, while glutathione S-transferase (GST) was only induced in var. Srpanjka. Chelate form of Zn increased the activities of GST and GPOD in both Simonida and Divana. Catalase activity was shown to be less sensitive to Zn treatment and was only induced in var. Srpanjka treated with Zn-EDTA where GPOD activity was not induced. Concentrations of Zn used for agronomic biofortification can induce oxidative stress in wheat leaves. The antioxidative status of wheat leaves could be a good indicator of Zn tolerance, whereas wheat genotype and chemical form of Zn are the most critical factors influencing Zn toxicity.
Highlights
Zinc (Zn) is an essential metal for plants, and adequate availability of this micronutrient is vital at all stages of plant development
In response to heavy metal (HM) treatment, plant antioxidative enzymes can show induction of activity correlated with increased concentration of HMs, biphasic response, or inhibition of activity at high concentrations of HMs where plant species, genotype, and growth-stage are the most important factors influencing the HM toxicity [12]
Differential tolerance mechanisms of plant genotypes to Zn toxicity are a promising tool to complement our understanding of Zn tolerance in plants [13]
Summary
Zinc (Zn) is an essential metal for plants, and adequate availability of this micronutrient is vital at all stages of plant development. This micronutrient acts as an enzyme cofactor and plays an important role in regulating metabolic processes like the synthesis of nucleic acids and proteins, pollen formation, carbohydrate metabolism, and auxin synthesis [1,2]. Excess of Zn, not being able to generate reactive oxygen species (ROS) directly through Haber–Weiss reactions, can indirectly induce oxidative stress in plants by different mechanisms such as activation of calcium-dependent systems, reduction of the glutathione (GSH) pool, and interruption of iron-mediated processes [9,10]. Differential tolerance mechanisms of plant genotypes to Zn toxicity are a promising tool to complement our understanding of Zn tolerance in plants [13]
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
