Phytohormones regulate plant responses to variable environmental conditions, in addition to growth and development. Our group focuses on elucidating the role of phytohormones, including their complex cross-talk, mainly under abiotic stress conditions.
Aims of our research
- Understanding of mechanisms of stress responses
- Elucidation of the mode of action of acclimation
- Promotion of plant stress tolerance by growth regulators
Our approach
Stress responses have temporal and spatial dynamics, which make them challenging to study.
- We investigate the phytohormonal role in water deficit, salinity, temperature stresses, nutrient deficiency, or different light intensity and quality.
- We evaluate the organ specificity of stress responses using detailed analyses of leaves, roots, and meristematic tissues.
- We have uncovered specific hormonal regulations associated with meristem protection and the critical role of roots in effective plant stress responses.
- We developed special thermoregulatory vessels to study shoot-root communication under temperature stress.
Based on our research and optimisation experiments, we obtained a deep knowledge of phytohormone changes under a wide range of abiotic stresses: drought, salinity, phosphate and nitrogen deficiency, ZnO nanoparticles, heat stress, cold stress, freezing stress, high/low light intensity, and exposure to different parts of light spectrum. Due to national and international collaborations, we also studied responses to biotic stresses: fungal infections, viruses, insects, nematodes, or wounding. Even though the main research in our group is carried out using the model plants Arabidopsis and rice, we have experience with other species as well (e.g., wheat, barley, and rapeseed).
Fig. 1. An example of the hormonal cross-talk under cold stress conditions in leaves, crowns, and roots of rice seedlings revealed by organ-targeted cold stress treatments (from Jarošová et al., 2024). Up-regulated levels are shown in red, down-regulated levels are shown in blue, and levels similar to the control are shown in green. Thin arrows indicate suppressed transport between leaves and roots. ABA – abscisic acid; DZ – dihydrozeatin; JA – jasmonic acid; tZ – trans-zeatin.
Fig. 2. Exogenously applied cytokinin meta-topolin-9-(tetrahydropyran-2-yl)purine (mT9THP) enhanced the thermotolerance of rice seedlings exposed to heat stress by stimulation of protective mechanisms before heat stress onset. The effect was more significant with previous acclimation by mildly elevated temperature (Prerostova et al., 2023).
Using our knowledge of hormonal changes during stress responses, we can modulate plant stress tolerance. We tend to find effective strategies for improving plant fitness using growth regulators. In the long term, we are testing cytokinins as promising stimulators of stress tolerance, which may have effects similar to acclimation by moderate stress.
We highly appreciate the existing collaboration with other scientific institutions such as:
- University of North Carolina, USA – Prof. Joe Kieber
- Departments of Genetics and Plant Physiology, Agricultural Research Institute, Martonvásár, Hungary – Prof. Gábor Galiba, Dr. Tibor Janda, and Dr. Gabriela Szalai
- Texas Tech University, Texas, USA – Prof. Lam-Son Tran
- Research Centre Julich, Germany – Dr. Fabio Fiorani and Prof. Ulrich Schurr
- Timiryazev Institute of Plant Physiology, Moscow, Russia – Prof. Vladimir V. Kusnetsov
and with numerous colleagues in the Czech Republic as well as abroad.