- M H Schoeman. D Lemmer and FJ Kruger
- ARC-Institute for Tropical and Subtropical Crops, Private Bag X 11208, Nelspruit 1200
- 2003
A study was conducted to evaluate the use of a fogger and chlorine dioxide sachets to control postharvest diseases of litchi fruit. The study consisted of two trials. The aim of the first trial was to establish the efficacy of fogging, using the disinfectant PIO, and chlorine dioxide sachets under packhouse simulation conditions. The aim of the second trial was to establish whether fogging during the containerization and overseas storage period would reduce the fungal infection rate. In both trials commercial SO2 treated fruit was used. The results showed that fogging during the shipping and marketing periods significantly reduced the early onset of fungal growth. Fogging at the packhouse stage appears to have little benefit, but adds to the general cleanliness of the packhouse. The more important periods are the shipping and marketing periods where some form of sanitation would help reduce fungal growth and new infections.
Summary:
- The study evaluated the use of a disinfectant fogger (F10) and chlorine dioxide sachets to control postharvest fungal diseases in commercially SO2-treated litchi fruit during storage and shipment conditions.
- Two trials were conducted: Trial A assessed efficacy under packhouse coldroom simulation conditions; Trial B tested fogging effects during containerization and overseas storage simulation.
- In Trial A, fruit were fogged daily with F10 for 1.5 minutes for 5 days or exposed to chlorine dioxide sachets; results showed minimal fungal infection immediately post-cold storage but increased rapidly during shelf life, with no significant difference among treatments.
- Trial B involved fogging treatments during shipment and storage abroad; fogging during shipment and storage significantly reduced fungal infection on days 5 post-cold storage compared to packhouse fogging alone.
- By day 7 of shelf life, no statistical differences were noted in fungal infection rates between the different fogging treatments.
- Fogging at the packhouse stage has limited benefit for reducing fungal infections but contributes to general packhouse sanitation.
- Fogging during shipping and marketing phases offers a transient reduction in fungal growth and secondary infections.
- The results highlight that sanitation during critical postharvest periods, especially shipping and marketing, is important to control fungal spoilage in litchis.
- Current practice of SO2 fumigation combined with cold storage remains essential, with fogging providing supplementary benefits.