Abstract: The effects of pretharvest methyl jasmonate（MeJA）spraying on disease resistance and postharvest quality of mango（Mangifera indica L.‘Tainong 1’）fruits as well as the related mechanism were investigated. The results indicated that，compared with the control fruits，50 μmol · L^-1 MeJA treatment significantly reduced the disease incidence of mango fruits at harvest，the disease index of non-inoculated mango fruits and the lesion diameter of mango fruits inoculated with C. gloeosporioides during storage. Moreover，preharvest MeJA treatment was effective in maintaining fruit qualities，as it increased vitamin C content，delayed the increase of soluble sugar and decrease of titrable acidity in mango fruit pulp during storage. Meanwhile，preharvest application of MeJA enhanced the activities of defense enzymes phenylalanine ammonia-lyase（PAL），peroxidase（POD），polyphenol oxidase（PPO）and β-1,3-glucanase（GLU）in the fruits during storage. In addition，the level of hydrogen peroxide（H₂O₂）was activated by the MeJA treatment during the early stage of storage. However，the contents of H₂O₂ and malondialdehyde（MDA）in the fruit were inhibited during the late stage of storage. These results indicated that the effects of pretharvest MeJA treatment on inducing disease-resistance and maintaining postharvest quality of mango fruits may involve the activation of the disease-related defense system and reduced membrane-lipid peroxidation.

Key words: mango, methyl jasmonate, postharvest, quality, defense enzymes, anthracnose, disease resistance