Physiological and molecular controls of plant transpiration efficiency: investigating the role of the ERECTA gene

We have identified a gene, ERECTA, in the model species Arabidopsis that influences transpiration efficiency, the ratio of photosynthetic carbon gain to loss of water via stomata. We will examine the way this gene works to coordinate the amount of photosynthetic machinery in the leaf with the leaf s stomatal conductance to diffusion of gases. We will determine the role of ERECTA in modifying leaf meristems, the regions where cells divide, and stomata, as affected by drought. We will also assess the connection of this role to that of ion content homeostasis. The study relates directly to improving water-use efficiency in agriculture, the major user of water in Australia and the world, and is central to the first National Research Priority.