The role of ethylene in mango fruit aroma volatiles biosynthesis

Abstract

SummaryUniformly green mature ‘Kensington Pride’ mangoes (Mangifera indica L.) treated with ethephon (500, 1000 and 2000 a.i. mg l–1), AVG (100, 500 and 1000 a.i. mg l–1) and 1-MCP (1, 10 and 25 μll–1 for 6 h exposure at 21 ± 1°C) and untreated fruit were used to investigate the role of ethylene in the biosynthesis of aroma volatile compounds in the fruit. The rate of respiration and ethylene production of the fruit were recorded during the ripening period at 21 ± 1°C. The ripe fruit were assessed for fatty acids and the production of aroma volatile compounds. The aroma volatile compounds were extracted by headspace solid phase micro-extraction and analysed using a gas chromatograph (GC) fitted with a flame ionization detector (FID) and GC-mass spectrophotometer. Exogenous application of ethephon increased the respiration rate, ethylene production and fatty acids content of the fruit during ripening whilst AVG and 1-MCP treatments suppressed them. Similarly, the exogenous application of ethephon increased the production of total aroma volatiles, monoterpenes, sesquiterpenes, aldehydes, total esters, alcohols and tetradecane, whilst AVG and 1-MCP treatments suppressed their biosynthesis. An increased concentration of ethephon from 500 to 2000 mg l–1 increased the concentration of fatty acids as well as aroma volatile compounds in the pulp of ripe fruit. The results suggest that biosynthesis of monoterpenes, esters and aldehydes in the mango fruit is strongly dependent on ethylene production and action.