According to predictions, in a few years the plants will have to face severe periods of drought as a result of climate change. However, the increase in carbon dioxide (CO 2 ) that will also be produced in the atmosphere could help some species to combat this lack of water.
A study published in Environmental and Experimental Botany has analyzed the response of barley ( Hordeum vulgare ) to the combination of two of the main consequences of climate change: drought and increased CO 2 . The results show how, in an atmosphere enriched in gas, plants are not so affected by drought, they grow more and photosynthesis rates are maintained for a longer time. The mechanism that makes this possible was already known to scientists: plants exchange water and air with the outside through stomata, which are holes located in the leaves and whose opening can be regulated depending on external conditions. . Some plants, when subjected to high CO 2 , partially close their stomata so that not as much water is lost and a more efficient use of it is allowed.
The researchers have highlighted that these results cannot be extrapolated to other types of crops. Each species presents its own strategies to face the limitations of the environment and not all plants have to respond in the same way to high concentrations of CO 2 and drought.
