Advances in control of postharvest diseases in tropical fresh produce.
Korsten L.
Author Affiliation: Department of Microbiology and Plant Pathology, University of Pretoria, Pretoria 0002, South Africa.
Proceedings of the International Conference on Postharvest Technology and Quality Management in Arid Tropics, Sultanate of Oman, 31 January-2 February, 2005 : 163-170
Abstract : With increased global trade, fresh produce is increasingly being moved over vast distances to foreign markets. This requires effective cold chain - and product management practices to ensure premium quality fresh produce with increased shelf life. Product safety has now also become an additional minimum requirement for market entry. Producers should therefore take cognizance of the impact postharvest treatments and - practices have on product quality and safety in a more holistic approach. Traditionally, exporters relied heavily on agricultural chemicals to provide effective crop protection. However, with global chemophobia producers have to be more resilient in terms of alternative postharvest treatments. This paper will deal with examples of new advances in control of postharvest diseases of tropical produce. Understanding microbial dynamics of the fructoplane form the basis of developing alternative disease control products that can ensure quality and safety. The impact fruit handling or - treatment have on the climax microbial community provides insight into the likelihood of foodborne - and postharvest pathogens to establish themselves and survive on the fructoplane as the product moves through the export chain. Ensuring product safety and quality starts in the orchard. Various preharvest factors such as stress, presence of endophytes such as Botryospheria spp. in mango trees, prevailing orchard temperature and - humidity conditions, worker hygiene, harvesting practices, transport to the packhouse and duration before removal of field heat provides some variables that can impact on ultimate quality and safety at the retail end. Packhouse hygiene, careful packing and sustaining the cold chain un-interrupted can similarly impact on fruit quality and safety in the postharvest environment. Improving handling, hygiene and cold chain management conditions in both the pre- and postharvest environments have shown in our studies to ensure improved litchi fruit quality and safety. Various alternative treatments could effectively reduce postharvest decay, extend shelf life and prevent introduction, attachment and survival of foodborne pathogens. Some treatments evaluated in our studies included biological-, physical- and integrated control and proved effective against a range of postharvest pathogens of citrus and subtropical crops. Combinations with natural plant extracts, soft chemicals, disinfectants and combinations with modified atmosphere packaging could provide effective control of Penicillium infection on litchi.