KARACHI – A workshop titled ‘Advances in ecophysiology of salt tolerance’ will commence at the University of Karachi today (Monday). A university official said on Sunday that the three-day workshop is being held under the auspices of the Institute of Sustainable Halophyte Utilisation, University of Karachi. Federal Urdu University of Arts, Science and Technology Vice-Chancellor Prof Dr. Muhammad Qaiser will be the chief guest at the inaugural session. The event will focus on recent advances in the research on halophytes -highly salt tolerant plants growing in saline lands that have gained considerable attention as non-conventional crops. The aim of the workshop is to discuss various aspects of salt tolerance mechanisms of halophyte which have enormous economic potential all over the world. The speakers at the workshop include the experts in the plant physiology, ecology and molecular biology both from Pakistan and abroad. Halophytes are plants which tolerate or even demand sodium chloride concentrations in the soil water they absorb. Depending on the habitat conditions they have developed different strategies to survive in sometimes very high salt content in the soil water. Depending on their tolerance and demands for sodium salts one distinguishes obligate and facultative halophytes. Obligatory means that they need some salt, facultative means they can live also under freshwater conditions. Further divisions are hydro-halophytes and xero-halophytes. Hydro-halophytes grow in aquatic conditions or on wet soil. Most mangroves and salt-marsh species along coastlines are hydro-halophytes. Xero-halophytes may grow in habitats where the soil is always saline but where the soil may dry out so much as to cause problems with water availability for the plant. Most species in desert areas are xero-halophytes. Many of them are succulent. Still another division is morphologically based. One distinguishes succulent halophytes, halophytes with salt bladders on the leaf surface, and those which excrete the salt with evaporation water, where the salt crystals remain visible on the leaf surface. Under lower salinity levels some plants are able to exclude the salt otherwise taken up by the roots.
