Postharvest Infiltration of BTH Reduces Infection of Mango Fruits (Mangifera indica L. cv. Tainong) by Colletotrichum gloeosporioides and Enhances Resistance Inducing Compounds

Mango fruits (Mangifera indica L.) were treated by vacuum infiltration of 1.0 mm benzo-(1,2,3)-thiadiazole- 7-carbothioic acid s-methyl ester (BTH) after harvest. Seventy-two hours after the treatment with BTH, the fruit were inoculated with 15 ll of conidial suspension of Colletotrichum gloeosporioides (1 · 105 conidia ⁄ ml) and incubated at 13 C, 85–90% RH for disease development. Disease incidence and lesion diameter in mango fruit after the inoculation were significantly (P < 0.05) reduced by the BTH treatment during the incubation. Peroxidase, polyphenoloxidase, phenylalanine ammonia-lyase, chitinase and b-1,3-glucanase activities and total phenolic compounds content in the fruits were all enhanced by the BTH treatment during the incubation. The catalase activity in the fruit was inhibited, whereas the level of hydrogen peroxide was increased by the BTH treatment during the infection. These responses may be involved in the induced resistance against the pathogen infection in mango fruit by BTH treatment. Application of BTH in fruit possesses promising results in the control of postharvest diseases as an alternative to traditional methods.