Pg. 16-23 Effect of fungicides and disinfectants in the prevention of litchi pericarp browning and control of postharvest diseases

Pericarp browning, desiccation and decay are the most important postharvest problems affecting litchi fruit exported from South Africa. The standard approach for preserving the quality of litchi fruit involves the use of sulphur dioxide SO₂-fumigation. This study compared the efficacy of 18 disinfectants and 9 fungicides with SO₂-fumication and an untreated control in preserving the marketability of stored litchi fruit. All nine fungicides and 18 of the disinfectants improved, to various de{lrees, the marketability of litchi fruit compared to the untreated control. The disinfectant, OA5 DP, and fungicide, prochloraz, demonstrated superior efficacy to SO₂-fumigation in preserving overall fruit marketability, whereas the disinfectant Frigate®, and fungicide benomyl, were equally effective as SO₂-fumication. Five quaternary ammonium containing disinfectants, OA5 DP, Terminator®, Formula 10®. Sporekill®, and Desogerm® two chlorine-based products. Harvest Wash®, and HTH®, and the fatty amine ethoxylate, Frigate® reduced the incidence of fruit infection, comparable with SO₂ fumigation. Similar results were obtained from benomyl, copper oxychloride, guazatine, iprodione and prochloraz.