Inthisstudy,weinvestigatedtheeffectsof6-benzylaminopurine(6-BA)–calciumchloride(CaCl2)–salicylicacid(SA)treatmentontheyellowingandreactiveoxygenmetabolismofharvestedbroccoliheads.Wedippedfreshbroccoliheadsinacompoundsolution(0.6mmol/L6-BA+40mmol/LCaCl2+3mmol/LSA)for5minandthenstoredthemat23°Cfor4days.Theresultsshowedthatthe6-BA–CaCl2–SApostharvesttreatmenteffectivelyretardedtheincreaseincolorvalues(e.g.,variationsfromblacktowhite,fromgreentored,andfrombluetoyellow)andthedeclineinchlorophyllcontentofthebroccoliheads.Comparedwiththecontrolbroccoli,therateofsuperoxideanionradical(O2·?)productionandthehydrogenperoxide(H2O2)contentwereloweredbythetreatment.Wealsofoundsignificantdifferencesintheactivitiesofsuperoxidedismutase(SOD),catalase(CAT)andperoxidase(POD)inthetreatedbroccoli.Basedontheseresults,weconsider6-BA–CaCl2–SAtoinhibittheaccumulationofreactiveoxygen,delaythedegradationofchlorophyll,andprolongtheshelflifeofbroccoliheadsat23°C.
