RESPONSE OF PHRAGMITES-AUSTRALIS TO WATER-STRESS FROM FLOODING TO DROUGHT

Leaf samples of Phragmites australis collected from five locations var ying from totally flooded to dry regime showed a sharp decrease in the fresh leaf water content of the plant from flooding to dry locations accompanied by an incomparable decrease in OP. This incremental osmoti c regulation occurred due to the accumulation of soluble sugars, amino acids, proteins, proline and the nutrient elements K, Na. Ca, Mg and Fe.Low OP under flooding was attributed to the condensation of sugars and amino acids into polysaccharides and protein. Both drought and flo oding conditions resulted in the accumlation of polysaccharides. prote in and proline.