Fruit were inoculated with Colletotrichum gloeosporioides by immersion in a spore suspension
and then were divided into two groups: one received a HT treatment (48 C, 20 min) combined with Ca
(1% w/v, 20 min) and the other was used as control. Afterwards, fruit were stored during 20 days at 12 C
to allow the development of the fungal infection. Anthracnose incidence and severity were estimated
visually while the development of the disease was analyzed by light and electron microscopy. HT-Ca
reduced anthracnose incidence and severity compared with the control. Microscopy analysis showed
that HT-Ca melted the epicuticular wax, which covered most of the stomata; this resulted in a lower
mycelial growth in HT-Ca fruit with respect to the control samples. HT-Ca also induced the formation of
round shaped vesicles, which corresponded with the greater accumulation of total phenolics observed in
treated fruit. HT-Ca was effective to delay the symptoms of anthracnose up to 10 days during storage of
papaya at 12 C