Polyamines On Postharvest Storage Physiology

studies on the Innuence of PAs on Postharvest Physiology ofbananaAn Guangiie(Department of Food Science and Engineering, South China University of TropicalAgriculture, Danzhou, Hainan, 57l737)AbstractThe category, quantity and distribution of PAs in banana fruit were investigated.Both the relation between postharvest and PAs varieties and Put influence onbanana'S physiology in room temperature(28C) and chilling temperature(5OC) werealso researched.The results show that there are mainly three kinds PAs in the banana fruit and thesequence 'of their concentration as following f Spm> Put> Spd. Their contentsvarieties as followings: Spd varies little while Put content accumulate in alltreatments during storage and Spm content becomes larger in initial stage thendecline, except its increasing in chilling fruit flesh.In room temperature Spm and Spd content increasing can lower banana ffoitsmaturing and Put's accumulation is due to the fruits' maturation. The experimentthat aPplication of Put shows that Put can inhibit chlorophyll discomposing andlower POD activity; Lower concentration (about 5mmol/L) can decrease respirationrate; ethylene's synthesis result in prolonging the storage time; Higher concentration(about l0,20mmol/L) Put can activate the respiration in some degree anddisadvantage to storage.In chilling temperature the relation between PAs and banana's chilling physiologyas following: In the peel, Pro's synthesis is competed with polyamine's synthesisand higher polyamine concentration can stabilize cell membrane better, in whichhigher Put content can inhibit chlorophyll's degrading. The experiment that treatedbanana with Put indicates f Put can activate Pro's synthesizing and decrease-4 1 -respiration rate, POD and PPO抯 activities, but has little influence on cell membrane抯 penetration. Then the conclusion is that endogenous PAs?increasing can reduce the chilling injure and application Put have no influence on chilling injury.Results of this research show that PAs as kinds of botany hormone have significant influence on postharvest banana抯 physiology.