Symptoms and the Associated Fungi of Postharvest Diseases on Non-Chemical Bananas Imported from the Philippines

Abstract

Recently, the preference of Japanese consumers for healthy agricultural products has led to the increase in importation of banana grown without chemicals (hereafter referred to as “non-chemical bananas”) mainly from the Philippines. Due to postharvest diseases, however, the marketability of the non-chemical bananas is affected, causing significant losses to importers and farmers. Hence, disease symptoms and the associated fungi of the non-chemical bananas from the Philippines were investigated, identified, and quantified in Japan from December 1997 to July 1998. The objective of the study was to provide benchmark information for further research to improve the quality of non-chemical bananas from the Philippines. Disease symptoms included crown rot, anthracnose, freckle, finger stalk rot, finger rot and finger end rot with an incidence of 86, 83, 71, 56, 11 and 3%, respectively. Twenty-five fungal genera were associated with these disease symptoms. The dominant fungi were Fusarium 49%, followed by Colletotrichum and Penicillium (8%), Verticillium (7%), Cylindrocarpon (5%), Cladosporium and Glomerella (4%), Thielaviopsis, Pestalotiopsis, Lasiodiplodia, Phoma (3%), Phomopsis and Aspergillus (1%) . The frequency of occurrence of other genera was less than 1%. Colletotrichum and Glomerella were also isolated from anthracnose while Phyllosticta was observed in freckle. Dominance and population of fungi of the nonchemical bananas were almost the same during the period from December 1997 to July 1998.