ABSTRACT
Plants face frequent periods of environmental stress that impairs their growth and reproductive capacity.Restrictionofplantgrowthcannotbeattributedtoonesingleprocess,becauseplantgrowth istheresultofmanyintegratedandregulatedphysiologicalandbiochemicalprocesses.Tosurvive andmaintainminimalgrowthpotential,plantsmustconformtoextremeenvironmentalconditionsentailingadaptivechangesinmetabolismandcellcomposition.Ofthevariousmechanisms enabling plants to cope with water stress, the most common is the accumulation of intracellular solutes,suchassugarsandfreeaminoacids.Themostfrequentnitrogen-containingcompoundsthat accumulateinplantssubjectedtodroughtandsalinityareamides,aminoacids,andpolyamines. Theaccumulationofprolineondehydrationduetowaterdecitorincreasingosmoticpressure isthemostrecentinformationconcerningtheosmoregulatoryroleofprolineinenvironmentally stressed plants.
