Higher CO₂ Level Means Higher Tolerance of Barley to Salinity

Barley is one of the most important crops in the world. But what does climate change do to barley in the future? A research by Usue Pérez-López of the University of the Basque Country (UPV/EHU) found that climate change will bring with it increased in tolerance to salinity in barley. It is predicted that aside from increased CO₂ levels, there will be an increase in salinity in the soil in the future, because of greater rate of evaporation. As a result of this increase in salinity the hydric state of barley plants will deteriorate and imbalances in their nutrition will occur due to excess sodium and chlorine (components of salt) and due to lack of potassium, calcium and nitrogen. In essence, the plant will produce less carbohydrates and proteins, which means a reduction in its growth.

Pérez-López found out that high concentrations of CO₂ attenuate the loss of water through the plant leaves, due to the fact that the stomas are kept closed and the plant tissues are dehydrated to a lesser degree. High levels of CO₂ considerably enhances the hydric state of barley. It also has a positive influence on the photosynthesis of the plant because, despite the fact that the plant keeps its stomas shut, the diffusion of CO₂ between the exterior and the interior of the leaf is greater. The oxidative stress level of barley (the oxidation suffered by a plant due to high salinity) was also determined. Pérez-López found that high concentrations of CO₂ alleviate this stress. The study concluded that the increase in CO₂ enables greater growth of barley plants subject to saline conditions, thanks to the improvement in their hydric state and turgescence, but, above all, to the increase in photosynthesis.

Read the complete article at http://www.basqueresearch.com/berria_irakurri.asp?Berri_Kod=1819&hizk=I.