The role of methyl jasmonate in mango ripening and biosynthesis of aroma volatile compounds

To study the role of methyl jasmonate in mango fruit ripening and biosynthesis of aroma volatiles, one lot of green mature preclimacteric 'Kensington Pride' mangoes was ripened under ambient conditions (21 +/- 1degreesC). The changes in endogenous levels of methyl jasmonate in the pulp during ripening were investigated. Another lot of green mature preclimacteric fruit was treated with methyl jasmonate vapour at different concentrations (0, 10(-3)M, 10(-4) M and 10(-5)M) for 12 h to study the role of methyl jasmonate on biosynthesis of aroma volatile compounds in the fruit. Following methyl jasmonate treatments, the fruit were then allowed to ripen under ambient conditions (21 +/- 1degreesC). Only trans-methyl jasmonate was identified from the pulp of 'Kensington Pride' mango. Concentration of trans-methyl jasmonate in the pulp was higher at harvest day (123.67 ng g(-1)) and decreased as the ripening progressed at the ripe stage (0.14 ng g(-1)). Methyl jasmonate treatments increased ethylene production at the climacteric stage and was more pronounced at a higher concentration (10(-3)M) of applied methyl jasmonate. Skin colour of ripe fruit was significantly improved with exogenous application of methyl jasmonate (10(-3)M). Methyl jasmonate treatments also increased the concentration of fatty acids as well as total aroma volatiles, monoterpenes, sesquiterpenes, aromatics, norisoprenoid, alcohols and esters in the pulp of fruit. However, exogenous application of methyl jasmonate tended to reduce production of n-tetradecane, especially on day 5 and 7 of ripening. In general, exogenous application of methyl jasmonate (10(-3)M) significantly promoted biosynthesis of ethylene, fatty acids and ripening and aroma volatile compounds during fruit ripening. Our experimental results suggest that methyl jasmonte is involved in early steps in the modulation of mango fruit ripening.