Mango anthracnose: New sources of resistance and effect of temperature on disease severity in <i>Mangifera</i> spp.

Anthracnose caused by Colletotrichum spp. is a major postharvest disease that can rot mangoes within eight days, affecting overseas shipment. In this study, eight Mangifera species (M. casturi, M. indica, M. lalijiwa, M. laurina, M. odorata, M. zeylanica, M. sylvatica, and M. rubropetala) and seven M. indica varieties (‘Totapuri’, ‘Nam Doc Mai’, ‘Maha Chanok’, ‘Kensington Pride’, ‘Keitt’, ‘Sunny’, and ‘Irwin’) were inoculated with C. asianum and evaluated for 25 days for anthracnose severity at two different temperatures, 11°C and 25°C. Anthracnose severity was significantly lower at 11°C than at 25°C. Significant differences were observed in disease severity among the eight species tested. Mangifera casturi exhibited the lowest anthracnose severity (6.1%). Among M. indica varieties, Sunny exhibited the lowest anthracnose severity (21.6%), followed by Keitt (21.9%). Cold treatment for 15 days helped to reduce anthracnose severity between 25% to 70% for M. lalijiwa, M. laurina, M. sylvatica and M. zeylanica and M. indica varieties ('Sunny', 'Irwin', 'Maha Chanok', 'Totapuri' and 'Nam Doc Mai'). On the other hand, anthracnose severity increased after cold treatment for 15 days for M. casturi, M. odorata, M. rubropetala, 'Keitt' and 'Kensington Pride' by 62-fold. Overall, tolerance to mango anthracnose in the wild species M. casturi and in the variety 'Sunny' is reported for the first time, indicating their potential as new sources of resistance. While cold temperatures reduced anthracnose severity in some Mangifera spp. and M. indica varieties, transporting temperatures must be optimized to reduce disease severity in cold-sensitive genotypes.