HIGH-TEMPERATURE CONDITIONING REDUCES HOT-WATER TREATMENT INJURY OF KENSINGTON PRIDE MANGO FRUIT

Mango (Mangifera indica L.) fruit can be injured by heat disinfestatio n protocols imposed to kill insects. We determined if mango fruit have the capacity to acclimate, thereby becoming more tolerant of heat dis infestation treatments. Conditioned 'Kensington Pride' mango fruit (7- hour heating-up period to a 37C core temperature maintained for less-t han-or-equal-to 12 hours) showed less pulp injury on ripening followin g hot water treatment (1.5 hours for previously conditioned fruit to 2 hours for fruit not previously conditioned) than fruit not conditione d before hot water treatment. During treatment, the core reached 47C a nd was maintained for 25 minutes. Extending the conditioning period by less-than-or-equal-to A2 hours beyond the 7-hour heating-up period (t otal of 19 hours) gave no additional benefit. Conditioning did not con sistently reduce peel injury that was hot water treatment-induced as i ndicated by irreversible loss of chlorophyll variable fluorescence.