59 M. Ozturk et al. (eds.), Sabkha Ecosystems, Tasks for Vegetation Science 46, DOI 10.1007/978-90-481-9673-9_8, © Springer Science+Business Media B.V. 2011 Abstract Increasing salinisation has significant and detrimental impacts on land, water and vegetation qual- ity, wildlife environments, agronomy and ecosystem functioning. This is particularly true for arid and semi- arid areas where high evapo-transpiration rates expose plants to further adaptive pressure. Unlike conventional crops, halophytes are plants that survive and are able to reproduce in environments (coasts, wetlands, and inland deserts) with higher salinity levels. These spe- cies, which represent about 1% of the world’s flora, have evolved complex mechanisms at different levels (whole plant, cellular, and molecular) enabling them to successfully cope with these hostile conditions. There are about a billion ha of salt-affected land world wide, which are unsuitable for agriculture and may therefore provide unique opportunities for “halo-biotechnologies”. Taking into account the increasing pressure on fresh water resources and considerable diversity of poten- tially useful halophytes, such an approach may help in the mid- and long-term to rehabilitate these mar- ginal zones and create sustainable production systems. Agriculture on saline soils is an alternative agriculture under a range of salinity levels in groundwater, and/or soils. A precondition for its use is the economic value added. Yet, fundamental prerequisites have to be con- sidered to ensure that this promising approach would be cost-effective and environmentally safe. It must yield economically viable crops at yields high enough to be accepted by the farmers. This should be concomi- tant with the development of agronomic techniques relevant for growing saline, water-irrigated crops in a sustainable manner. Most importantly, these practices should be sustainable, ecologically well-tolerated and not lead to further damage of natural environments. If applied successfully, such an approach may lead to domestication of wild, salt-tolerant plants to be used as food, forage, oilseed crops, as well as pharmaceutical or ornamental plants. Soil desalination represents also important tasks for the so called cash crop halophytes. The successful rehabilitation of saline marginal zones by introduction of halophytes largely depends on col- lecting reliable data on salt-tolerance limits during life cycle of the respective candidate species. In this con- tribution, we present an overview of new data gained under saline conditions during the last years with respect to halophytes of interest and discuss their likely implications at applied level. 1 Introduction Growth of the human population by 50%, from 6.1 bil- lion in mid-2001 to 9.3 billion by 2050 (http://www. unfpa.org/swp/2001/), requires a significant and con- comitant increase of crop production to ensure food security, especially in the developing countries. Recent estimations of the Food and Agriculture Organization of the United Nations (FAO) indicate that more than 850 million people are suffering from chronic malnu- trition. Additionally, this problem becomes enhanced Current Challenges and Future Opportunities for a Sustainable Utilization of Halophytes Ahmed Debez, Bernhard Huchzermeyer, Chedly Abdelly, and Hans-Werner Koyro A. Debez ( ) and B. Huchzermeyer Institut für Botanik, Leibniz Universität Hannover, Herrenhäuser Str. 2, 30419 Hannover, Germany e-mail: ahmed_debez@yahoo.com C. Abdelly and A. Debez Laboratoire des Plantes Extrêmophiles, Centre de Biotechnologie de Borj-Cedria (CBBC), BP 901, Hammam-lif, 2050, Tunisia H.-W. Koyro Institut für Pflanzenökologie, Justus-Liebig Universität, Giessen, Heinrich-Buff-Ring 26-32, D-35392 Giessen, Germany