Pg. 6-9 Preliminary evaluation of SO₂ sheets to prevent postharvest diseases of South African export litchi fruit

A study was conducted to establish the efficacy of SO₂ sheets and liners in terms of postharvest diseases and browning of HLH Mauritius litchi fruU. The study consisted of 3 trials. The first trial was aimed at establishing whether SO₂ sheets have the potential to replace conventional sulphur fumigation. The second and third trials were designed to determine whether the sheets can play a supplementary role when used in combination with sulphur fumigation. The results
showed that it was not possible to obtain uniform bleaching when using the sheets on their own. However, the sheets were found to significantly reduce the incidence of fungal infections when placed in the bottom of boxes containing commercially SO₂ fumigated fruit. Residue analysis indicated the sheets not to increase SO₂ residues in the arif of the fruit. At this stage it is recommended that the sheets be used without liners after regular fumigation.