Global demand for food and farmland is rapidly growing due to increasing world population and urbanisation. As a result current estimates indicate that food production will have to increase by up to 70% by 2050 to keep pace with projected demands. Suitable resources for future agricultural expansion are however limited due to competing land and water uses for human consumption and non-food crops production. Thus, looking forward, we currently face one of the greatest challenges of the 21st century: to meet the world’s future food security and sustainability needs, food production must grow substantially despite a substantial decline in the availability of productive resources (soil and water). It is now clear that this conundrum cannot simply be solved with currently available soil and water resources and that the brackish/saline ones, nowadays unproductive, have to be included in the equation. Despite this, there is a growing recognition in the scientific and research and development communities of the limitations of current food production technologies. This perhaps is a reflection of the fact that crop selection process has been developed without considering the constraints occurring in more marginal and extreme environments. As a result, this selection for higher yields under optimal conditions during the green revolution of late 20th century has dramatically reduced the tolerance of elite crops to abiotic stresses. Fortunately, 450 million years of land plant evolution has generated biological complexity, which has allowed the so-called “extremophiles” to adapt to extreme environments, ranging from high salinity environments to extreme temperature changes and drought conditions in desert environments. Amongst these extremophiles, halophytes are an exciting group of plants that shows an elevate tolerance to salinity, thriving in salt concentrations damaging for most other angiosperms.
The main objective of the HALO project is to elucidate the complementary morphological, physiological and anatomical characteristics that enable dicotyledonous halophyte to be successful on saline soils, including their unique ability to sequester cytotoxic Na and Cl ions in specialised external structures called salt bladders. This will reveal the fine print of one of the most interesting mechanisms evolved by plants over the course of evolution not only to deal with NaCl toxicity but also use it to thrive in these otherwise hostile NaCl-rich environments, opening up novel and previously unexplored breeding targets to improve salt tolerance in crops.
