Stomata are pores located on the surfaces of leaves that allow gaseous exchange with the atmosphere. When a whole plant is exposed to light, the stomata open wide to maximize uptake of CO2 for photosynthesis. In the dark, on the other hand, all stomata remain closed to prevent excessive loss of water.
Scientists Laura Serna and Jorge Casal at University of Castilla-La Mancha, Toledo, Spain, have recently discovered that stomata in Arabidopsis thaliana open individually and independently from each other. Those stomata subjected to light will open while the shaded neighbour stomata remain closed. This helps plants to optimize the water balance and CO2 acquisition. The opening responses is triggered by the release of a light receptor called Phototropin1 from the cell membrane to the cell interior. The mechanism appears to be basic to the functioning of stomata in other plants. “Alphagalileo” Dr. Laura Serna, E-mail: laura.serna@uclm.es, www.plosone.org |
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