Optimizing Crop Plant Stomatal Density to Mitigate and Adapt to Climate Change.

Plants take up carbon dioxide, and lose water, through pores on their leaf surfaces called stomata. We have a good understanding of the biochemical signals that control the production of stomata, and over the past decade, these have been manipulated to produce crops with fewer stomata. Crops with abnormally low stomatal densities require less water to produce the same yield and have enhanced drought tolerance. These "water-saver" crops also have improved salinity tolerance and are expected to have increased resistance to some diseases. We calculate that the widespread adoption of water-saver crops could lead to reductions in greenhouse gas emissions equivalent to a maximum of 0.5 GtCO₂/yr and thus could help to mitigate the impacts of climate change on agriculture and food security through protecting yields in stressful environments and requiring fewer inputs.