Poster Presentation Science Protecting Plant Health 2017

Investigations into alternative post-harvest treatments for crown end rot of banana. (#346)

Peter R Trevorrow 1 , Kathy R Grice 1 , Kaylene L Bransgrove 1
  1. Department of Agriculture and Fisheries, Mareeba, QUEENSLAND, Australia

Crown end rot (CER) of banana affects the cushion or crown portion of complete hands or clusters of banana during the ripening process or at the point of sale. Symptoms can range from superficial fungal growth on the cut crown surface, to minor discolouration of the crown tissue, through to complete breakdown of the crown and pedicel tissue with necrosis extending down into the fingers. A range of fungi are known to cause these symptoms world-wide and in north Queensland, the organisms in order of prevalence include: Musicillium theobromae and Fusarium equiseti-incarnatum complex, Thielaviopsis musarum and Colletotrichum musae. Management of CER is centred on the use of post-harvest fungicides and two products are currently registered for use, Sportak® which contains the active prochloraz and Tecto® that contains thiabendazole, however both products have issues or limitations. Prochloraz has workplace health and safety concerns when applied under certain packing shed situations and laboratory studies have shown a reduction in sensitivity to some of the CER organisms to both products, but more so to thiabendazole. Because of the above concerns, a laboratory assay has been developed to screen a range of products that may have efficacy across the broad spectrum of causal fungi and that could be used by organic growers. The products include: fungicides, biologicals, quaternary ammonium solutions and household products (eg. vinegar and bicarb soda). Early screening results have indicated that some products have efficacy (although limited) across the range of crown rot organisms, whereas efficacy of other products was quite selective or specific to a fungus. Products that show some promise will be further evaluated to prove efficacy of on banana clusters and to ensure that the products do not have any phytotoxic effects on banana fruit.