Research Article

The Role of Zinc in Plant Growth and Human Nutrition Amid Climate Change

İbrahim Ortaş

Department of Soil Science and Plant Nutrition, Çukurova University, 01330, Adana-Türkiye. 

*Corresponding author e-mail: iortas@cu.edu.tr, ibrahimortas@gmail.com

(Received: 25/08/2025; Revised: 10/10/2025; Accepted: 19/10/2025; Published: 20/12/2025)

ABSTRACT

Since zinc (Zn) has significant effects on wheat (a major food source for human health) growth, plant production is related to grain Zn concentration and is indirectly related to biofortification and climate change mitigation. Turkish soils have a severe Zn deficiency, which directly affects human nutrition through wheat plants. Genotypic variation in tolerance to Zn deficiency is well understood and may be related to differences in root growth and morphology, as well as mycorrhizal dependency and atmospheric carbon fixation. Two greenhouse experiments were conducted to determine the effects of Zn addition on wheat genotypes and plant growth and carbon dioxide fixation on Zn-deficient soil from the Central Anatolia Region, using forty bread and fifteen durum wheat genotypes in the first (Sultanönü soil) and second (Çomaklı soil) experiments, respectively. Plants were grown with (+Zn: 10 mg Zn/kg soil) or without (-Zn) Zn application in a randomised design. Plant growth, particularly in durum wheat, was significantly depressed in the control plant (−Zn) grown in Sultanönü soil. Zinc application more than doubled shoot biomass on average. Bread wheats generally out-yielded durum under −Zn. Resistant bread types included Kırkpınar, Bezostaja, and Aslım (rye), whereas sensitive durum included Kızıltan, Ç.1252, and Kunduru. Similar genotype rankings were reproduced in Çomaklı soil, with varieties, Zn, and their interaction being highly significant. Durum wheat genotypes were more susceptible to Zn deficiency than bread wheat genotypes, and this was related to less root production in durum wheat compared to bread wheat. Arbuscular mycorrhizal (AM) infection levels were low and irregular across genotypes and Zn treatments in both soils. Across genotypes, +Zn consistently elevated levels of tissue C and levels of estimated plant fixed CO₂ relative to −Zn. In Sultanönü, −Zn Kunduru fixed ~8.84 g CO₂ kg⁻¹ soil, whereas +Zn Kunduru fixed ~14.44 g CO₂ kg ¹ soil. Ranges spanned ~16.6 to 36.0 g CO₂ kg⁻¹ soil across genotypes, with Aslım (rye) among the highest. In Çomaklı, +Zn increased CO₂ fixation from ~1.4 to 4.4 and ~5.5 to 11.2 g CO₂ kg⁻¹ soil depending on genotype. These patterns underscore a link between adequate Zn nutrition for human nutrition, biomass accrual, and carbon capture potential, which is essential for combating climate change.  

Keywords: Mycorrhizae, wheat genotypes, rhizosphere, root length, shoot-root ratio