Works as a professor of Molecular Plant Biology since 2016. Hannes is interested to understand the immediate molecular switches by which plants sense changes in the surrounding environment. He studies stomatal regulation in response to elevated CO2, drought, air pollutant ozone and ways how to apply this knowledge for modulating crops water management. Jointly with collaborators from Finland and US, he unraveled guard cell anion channel SLAC1 and has been defining mechanisms by which SLAC1 activity is controlled by different environmental factors such as CO2 and ozone. He is also interested in developing technological solutions for plant diagnostics. Such as multi-cuvette gas exchange systems that allow parallel but independent measurement of several plants whole plant stomatal responses to various stimuli. More recently also portative instruments applicable for researching gas exchange of large number of cereal leaves in natural settings. These instruments are now also offered to the community via spin-off company PlantInvent.