METHOD: Chemical Assay CONDITIONS: Growth Chamber - 14h light at 18-22C or 2-4C METHOD NARR: Five-week-old plants were subjected to 10 days of cold acclimation. Cold hardiness was measured by an electrical conductivity test. Th that caused a 50% loss of total leachate was designated as the killing temperature. Abscisic Acid (ABA) was extracted and purified and immunoassay was performed. A commercial EIA kit was purchased and the suppliers protoco Elevated ABA level does not have to exist at time of full hardiness development. Under salt stress there is one large transitory increase of ABA in contrast to the one or two small increases seen under cold stress. AUTHOR EXt show any interrelationship in the levels of free and conjugated ABA during potato cold acclimation, suggesting that conjugated ABA is not a source of the transitory increases of free ABA. Conjugated ABA is also not a major catabolitato during cold acclimation.