THE EFFECTS OF FRUIT MATURITY AT HARVEST ON DISEASE DEVELOPMENT IN LYCHEE DURING STORAGE

Abstract

At harvest, lychee fruit of three maturity levels: M3 (31-60% surface red), M4 (61-90% surface red) and M5 (91-100% surface red), were either treated with hot benomyl (500 ppm at 52 °C for 2 min) and air dried, or left untreated prior to PVC wrapping in punnets, and storage at 5 °C. The fruits were assessed weekly between 2 and 5 weeks after harvest. nog Browning of the pericarp and disease development were absent from fruit of M4 and M5 maturity levels 2 weeks after harvest, while > 50% skin browning had developed on the M3 fruits. Browning had appeared on all fruits by 3 weeks after harvest. Similar levels and spectra of fungi were recorded from fruits of the three maturity levels, and were more prevalent in fruits that were not dipped in hot benomyl. Cladosporium sp. and Fusarium sp. were the most commonly detected fungi. Treatment in hot benomyl appeared to give greater control of side lesions than stem end lesions.