Infection Of Alternaria Alternata On Quality And Physiology Of Mango Fruits During Storage

Disease infection and postharvest decay has become the most important factor which restricts the sustainable development of mango industry in China. In this research, effect of Alternaria alternata on quality, storage condition including storage time, temperature, illumination, and changes of MDA contents, the activities of POD, APX, PPO in mango was studied. A method for determination of Tenuazonic acid (TeA) in mango fruits was established based on Ultra performance liquid chromatography-mass spectrometry(UPLC-MS). The main results were shown as follows:Effect of storage condition was studied in this paper, including storage time、 temperature、illumination. The results showed that, Infection level of Alternaria alternata against mango was different under different storage conditions:the mango decay index increased gradually with the extension of storage period and the rise of storage temperature, mango decay index was lowest under 12h light+12h intermittent illumination.Effect of Alternaria alternata on quality against mango was studied in this paper. Quality of Fruit healthy tissue were determined when the fruit disease spot diameter extended to 2cm. The results showed that:Quality of four varieties mango were changed after the infection of Alternaria alternata cake, content of reducing sugar, titratable acid, Vc decline, the pH value shows an increasing trend except xiangya mango; Soluble solids content of all treated mango all marked difference with CK.Effect of Alternaria alternata on changes of Malondialdehyde (MDA) contents, peroxidase dismutase(POD), ascorbate peroxidase(APX) and polyphenol oxidase(PPO) in mango was studied in this paper. The results showed that:Compared with that in control, MDA content shows an increasing trend after 120h, and activity of APX shows an increasing trend at 96h and 120h, activity of PPO was higher than Ck during 96h, activity of POD shows an increasing trend at 72h, marked difference with Ck.A method for the determination of Tenuazonic acid (TeA) in mango fruit was estimated based on Ultra performance liquid chromatography-mass spectrometry(UPLC-MS).The recoveries ranged from 82.60%～90.45% with relative standard deviations less than 6.67% of the alternaria toxins.