It is likely that stomata arose early in the evolution of land plants. During the development of land plants stomata have attained various functions, but the main tasks of these pores in the leaf surface is the uptake of carbon dioxide (CO2) into leaves. Open stomata provide a pathway for CO2 uptake that supports photosynthesis. However, stomata also cause loss of water through transpiration and therefore they are closed by plants to protect them against drought. In this project we are studying how stomata have obtained their specific properties in diverse plants species, during evolution.
We were able to show that the biophysical properties of stomata differ between ferns and seed plants. In both groups of plants stomatal movements are enforced by two neighboring guard cells that surround the central pore. However, guard cells of seed plants function autonomously, while their counterparts in ferns are in connected by cell-to-cell contacts (Voss et al., 2018). This observation indicates that ferns control their stomatal movement in a different manner as seed plants, which was conformed with molecular biological data (Sussmilch et al., 2021). We now focus on transport processes in fern guard cells, which are fundamental for stomatal movements, using biophysical techniques. The goal ist to understand how stomata have changed in evolution and obtained the control mechanisms that regulate CO2-upatke and transpiration in modern crop plants.