Consolidating the Asian vegetable industry, building on past achievements and action for the future

Background: This is a national project run from Central Queensland University and involving researchers from several organisations including Queensland DPI, NTDPIF, NSW Ag, Ag Victoria, TIAR, Agriculture WA and several private companies.

Objectives: The objective of the project is to aid in the development of new or existing production of Asian vegetables in Australia. In Tasmania, the project is concentrated on reducing fungal storage rots of Japanese squash (Kabocba). Approximately 1000 t of Kabocha is exported to Japan from Tasmania each year.

Work undertaken to date: Several treatments have been investigated over the last three seasons in an attempt to reduce fungal storage rots. Acetic acid (AA) fumigation has been trialed to reduce fungal storage rots of Kabocha. AA has been shown by overseas researchers to be effective experimentally at reducing fungal rots on a range of fruit and furthermore is a relatively benign chemical, being used widely in the food industry. In some experiments where Kabocha were artificially wounded, AA fumigation was effective at reducing storage rots. However in unwounded fruit, fumigation was unable to reduce storage rots. One of the main storage rotting fungi, Trials have shown one of the main storage rotting fungi Fusarium cu/morum to be inactivated by acetic acid only at concentrations much higher than those published for other storage pathogens and at concentrations phytotoxic to Kabocba. In addition Fusarium often develops from the stalk or button end of the fruit after some time in storage, suggesting it may reside internally within the fruit tissue, where it is unable to be killed by the fumigant.