Growing global population will inevitably effect food consumption as well as water resources. This means that we have to find innovative ways to produce more food using the least amount of resources possible. Now a new research at the Technical University of Munich found a way to develop such plants that would conserve water without limiting their ability to absorb carbon dioxide.
This is a great challenge, because the bigger the plant – the better for our food needs. However, big leaves also lose a lot of water, but are needed for photosynthesis. Now scientists developed an approach which should help activate inherent water-conservation mode, which is normally used when water is scarce. This is extremely important, because currently agriculture is responsible for a major portion of water consumption and the rise of sea levels – water is taken from the ground returns to the oceans.
Plants ability to regulate gas exchange is crucial for water consumption. Stomata, pores in the leaves of the plants, are the path for CO2 and water vapour exchange. It is possible to close stomata, but then plant cannot absorb carbon dioxide. When water is scarce plants reduce internal CO2 concentrations, which makes CO2 absorption more effective, which means that not all open stomata are needed. Activating this mode permanently is the path scientists chose to go.
This new study showed that a plant hormone called abscisic acid turns on this water-saving mode. Scientists found that there are 14 receptors responsible for perceiving this plant-specific hormone signal and increasing production of some of these receptors causes plants to switch to the water-saving mode even when water is not scarce. This allows saving up to 40% of water without affecting growth of the plant, but receptors have to be selected very carefully.
Erwin Grill, co-author of the study, said: “It remains to be seen if crop plants such as wheat, corn, and rice can produce more biomass with the same amount of water using this mechanism. We are optimistic. Since the mechanisms involved are present in all plants, it should be possible to transfer these results from the model plant Arabidopsis to crop plants”. Field experiments is the next important step and we will have to wait and see if these results can be equally well reproduced in real life conditions as they were in laboratory.