The level of quiescent infection of Alternaria alternata in mango fruits at harvest determines the postharvest treatment applied for the control of rots during storage.
Prusky D., Shalom Y., Kobiler I., Akerman M., Fuchs Y.
Author Affiliation: Department of Postharvest Science of Fresh Produce, The Volcani Center, Bet Dagan 50250, Israel.
Postharvest Biology and Technology 25 : 339-347
Abstract : The effectiveness of different postharvest treatments to control different levels of quiescent infections of A. alternata causing Alternaria rot in mango (cultivars Tommy Atkins and Keith) fruits during storage was compared. A combined hot water spray and fruit brushing (hot water brushing-HWB) treatment for 15-20 s with 225 µg ml-1 prochloraz was the most effective treatment to control Alternaria rot in fruits with a high relative quiescent infected surface (RQIS) rating of 36 at harvest. Comparable control was obtained with the commercial treatment of 900 µg ml-1 prochloraz spray. However, Alternaria rot in mango fruits with an intermediate level of RQIS rating of 25 was controlled by HWB treatment alone or HWB with chlorine (300 µg ml-1 Troclosene Na). HWB alone was effective enough to control postharvest decay in fruit with an RQIS of five. Present results have indicated that effectiveness of postharvest HWB and prochloraz applications are dependent on the quiescent infected area of the fruit by A. alternata at harvest. An RQIS rating, before harvest, has resulted in the use of effective, mild, fungicides as a single postharvest treatment thus avoiding wide use of less friendly synthetic fungicides.