delaying of postharvest senescence of lisianthus cut flowers by salicylic acid treatment

Salicylic acid (sa) is considered to be plant signal molecule thatplays a key role in plant growth, development, and defense responses. thephysiological mechanism of exogenous sa to affect the senescence of cutlisianthus flowers during vase life was investigated. fresh cut lisianthusflowers were treated with distilled water (control), 0.5, 1 and 2 mm sa andthen held at 25 ?c up to 12 days. exogenous sa supply at 1 mm extendedvase life, which was associated with reduced electrolyte leakage and mdacontent. sa treatment also reduced activity of lipoxygenase (lox), whichis responsible for membrane lipid peroxidation. sa treatment also enhancedactivities of catalase (cat) and ascorbate peroxidase (apx) and decreasedh2o2 accumulation during vase life. thus, exogenous sa supply couldmaintain membrane integrity by increasing antioxidant system activity,thereby retarding the senescence of cut lisianthus flower during vase life.