How do we know when the plants are unhappy about their surroundings? How can we tell when they get stressed and try to acclimate to the new conditions? How successful will this acclimation be?

Inside the plant cells, environmental stress activates many kinds of stress signalling pathways. Together these pathways make a complicated network that controls expression of genes, physiology and development of the plant.

A very special role in this network is played by the energy organelles, the mitochondria and the chloroplasts. These organelles work together to produce biochemical energy for the plant. But during stress they also become the key elements of the signalling network that literally make life and death decisions for the plant.

I am curious how the plant energy organelles play this dual role of "power factories" and "the ministry of defense" at the same time. In the University of Helsinki and at the Natural Resources Institute of Finland (Luke) I study how photosynthesis and respiration perceive the changing environment, how they are modified during stress and what are the molecular mechanisms that link energy metabolism with the stress signalling network.

At Luke and at the University of Helsinki we develop new ways to measure and image photosynthesis and respiration in vivo, for example, by looking at flash-induced chlorophyll fluorescence. Since the energy organelles are so intimately linked to stress reactions, this means that we are at the same time building new technologies to detect plant stress.