Red tamarillos (Cyphomandra betacea) : post-harvest control of fungal decay with hot water and imazalil dips

Abstract

Abstract A hot water dip at 50°C for 8 min effectively controlled quiescent infections in red tamarillos (Cyphomandra betacea (Cav.) Sendt.) caused by Colletotrichum gloeosporioides (Penz.) Arx and C. acutatum Simmonds. This dip reduced the percentage of fruit with body lesions without significantly increasing peduncle necrosis. Fungi colonising damaged peduncle tissue were controlled using an imazalil dip (1 min at 15–20°C) at 250 mg active ingredient/litre. The method of imazalil application (in hot water, as a separate cold water dip, or in wax) did not affect its efficacy. Imazalil residues in skin, pulp, and whole fruit were lowest when the fungicide was applied as a separate cold water dip. Storage disorders were significantly reduced using the hot water/imazalil dip, allowing 7 days shelf-life at 20°C after 8 weeks cool storage at 3.5°C.