MSc student (Adv. Irene Lichtscheidl)
Core Facility Cell Imaging and Ultrastructure Research
University of Vienna

Abstract  

70% of all heavy metals (HMs) and their compounds found in the human body come from food. HMs are natural trace elements with a density greater than 5 g cm-3 and could either be essential or non-essential. For example, zink (Zn), and nickel (Ni), are essential for the growth of plants in low concentrations, but their excessive amounts in the soil above threshold values result in toxicity. Due to an exponential increase in the use of HMs in several industrial, agricultural, domestic and technological applications, human exposure to HMs has increased. Thus, the importance of improving agricultural yield and remediating the environment cannot be overemphasized. Finding ways to enable agricultural plants to grow in suboptimal environmental conditions which will not only increase food production but remediate the environment is a hot topic of our time. In this study, we investigated the involvement of phytohormones on the growth performance and stress tolerance of wheat. Triticum aestivum most widely cultivated wheat was used as an agricultural plant to investigate firstly, the effects of different concentrations of Zn and Ni on the plant's metabolic system. Zn and Ni are HMs that are currently widely used in many technical fields and agriculture. Secondly, to investigate the possible involvement of phytohormones Methyl jasmonate (JA) and Strigolactone (SL) on the growth performance of wheat, and thirdly, to investigate the possible involvement of phytohormones JA and SL on the ability of wheat plants to withstand heavy metal-induced stress. This study was carried out in a two-phased experimental design, in which the effects of HMs and the possible involvement of two phytohormones on the growth performance and stress tolerance of wheat plants was investigated. The results showed that, upon treatment of wheat plants with HMs, the negative effects on the plant's parameters studied increased with an increased concentration of the respective HMs applied to the soil. For the possible involvement of the phytohormones on the growth performance and stress tolerance of wheat, both phytohormones inconsistently influenced all plant parameters studied. Firstly, JA in all concentrations applied variably affected all parameters studied but generally speaking, JA 10-6 M and 10-8 M were the concentrations that frequently showed significant influences on the various parameters studied. Secondly, all concentrations of SL applied inconsistently affected all plant parameters studied. But generally speaking, the concentration 10-5 M, 10-7 M and 10-9 M most frequently showed significant effects on the shoot length in nickel treated soils.