RESUMO
Mangoes (Mangifera indica L.) 'Manila' were subjected to the USDA-approved hot water treatment and then exposed to synthetic air mixtures containing 0.5, 0.75 or 1 ml l(-1) of ethylene for 6, 12 or 18 h at 25 degrees C, to induce accelerated ripening. After treatment the mangoes were allowed to ripen in air at 24-25 degrees C. The content of 1-aminocyclopropane-1-carboxylic acid (ACC) and ACC oxidase (ACO) activity increased in fruit treated with 0.5 and 0.75 ml l(-1) of ethylene for 6 or 12 h. Ethylene production was reduced in fruit treated with 1 ml l(-1) of ethylene. This was due to the decreased of ACC synthesis rather than to lower ACC oxidase activity. Treatment with 0.5 ml l(-1) of ethylene for 12 h was found best for accelerate ripening; fruits were fully ripened and edible 3 days after treatment, compared to 6-7 days for untreated mangoes.