Effect Of Salicylic Acid Treatment On Disease Resistance And Softening Of Postharvest Apricot Fruits

Xinjiang apricot fruits (Saimaiti) were used to investigate the effects of0.002g/L、0.01g/L or0.05g/L salicylic acid treatment combined with controlled vacuum-infiltration on the disease resistance, softening, physiological characteristics, storage quality and25℃shelf-life quality of postharvest apricot fruits. By determining disease incidence, disease index, hydrogen peroxide (H2O2) and total phenols content, superoxide anion(O"2.) production rate, catalase (CAT), superoxide dismutase (SOD), peroxidase(POD), polyphenol oxidase(PPO), peroxidase(PAL), chitinase(CHT) and β-1,3glucanase(GLU) activity of apricot fruits in the storage, study the effect of SA treatment on disease resistance of apricot fruits; By determining firmness, original pectin, soluble pectin, cellulose and malondialdehyde (MDA) content, membrane permeability, polygalacturonase(PG), cellulase and lipoxygenase (LOX) activity, study the effect of SA treatment on softening of apricot fruits in ripening. By determining respiratory rate, ethylene production,1-amino-cyclopropane-l-carboxylic acid (ACC) content, ACC oxidase(ACO) and ACC reductase(ACS) activity, study the effect of SA treatment on physiological characteristics of apricot fruits in the storage. By determining weight loss, firmness, chlorophyll, vitamin C(Vc), total souble solids(SSC) and titratable acidity(TA) content, disease incidence and disease index, study the efeect of SA treatment on quality of apricot fruits in the storage.(1) O.Olg/L SA can effectively inhibit CAT activity in the early incidence of apricot fruits, and promote H2O2content risen, increase SOD, POD, PPO, PAL, CHT and GLU activity, control O-2. and total phenolic content increased, induce disease resistance enhanced and reduce the desease incidence of apricot fruits during storage.(2)0.01g/L SA can effectively inhibit the firmness and pectin content increased, control membrane permeability, soluble pectin, cellulose and MDA content increased, delay the peak of PG and LOX activity emergenced and reduce the peak to keep the rise of cellulase activity of apricot fruits, impacting the softening of apricot fruits during storage. (3)0.01g/L SA can significantly slow down the respiratory rate, ethylene production, ACC content, ACO and ACS activity in the peak and reduce the peak of the apricot fruits during storage, impacting the physiological characteristics of apricot fruits during storage.(4) O.Olg/L SA can effectively inhibit the rate of weight loss increased, decline of firmness, slow chlorophyll and Vc content declined, reduce SSC and TA lost, and reduce disease incidence of apricot fruits during storage, affecting the storage quality of apricot fruits during cold storage. O.Olg/L SA can delay disease incidence and disease index reducd, slow firmness and Vc content, reduce SSC and TA content declined of apricot fruits, affect the quality of apricot fruits during shelf life.