Effect of sulphur dioxide and cold on survival of insects during the storage of table grapes (TG15003)
Status: Completed project
What was it all about? With Australian table grape exports increasing rapidly in recent years, this project sought to strengthen the relationship with the Chinese market specifically. It looked at six potential insect pests of concern, producing data to demonstrate that, should they make their way into consignments, they will not survive current cold and sulphur dioxide (SO2) treatments – giving growers, exporters and importers added peace of mind.
The insects included:
- Long-tailed mealybug (Pseudococcus longispinus)
- Ladybird beetle (Chilocorus sp.)
- European earwig (Forficula auricularia)
- Argentine ant (Linepithema humile)
- Carpophilus beetle (Carpophilus hemipterus)
- Two-spotted spider mite (Tetranychus urticae).
Their survival was tested in conditions similar to those experienced during export shipping to China and other Asian countries (transit temperatures for table grapes are generally around 1°C, with SO2-generating sheets used primarily to control fruit rot, and transit times of two to four weeks or more).
Key findings were that:
- After approximately two weeks of cold storage, all mealybugs, ladybird beetles and Carpophilus beetles died, with or without SO2 sheets – though the presence of SO2 did substantially increase mortality within the first week of storage.
- It took eight weeks for absolutely every two-spotted spider mite to die with or without SO2, though 95 per cent of the mites were eliminated after four weeks.
- European earwigs were the hardiest insect tested – cold alone did not kill the majority of the bugs, with 70 per cent still alive after eight weeks in cold storage. But the addition of SO2 saw a substantial increase in mortality, with about 92 per cent of the bugs dead after four weeks.
The research also revealed that during shipment, SO2 levels will be substantially higher at the tops of table grape cartons, where the sheets are generally placed. The researchers note that this new finding could explain anecdotal reports of rots always seeming to occur in the bottom of cartons – not because of moisture pooling as thought, but because of the distribution of SO2. More research will be required to look into this, and possible solutions.
Full details of this research can be found in the project’s final report, which is available to order at www.horticulture.com.au/about/resources-publications-final-reports (final reports are free to Australian horticulture levy payers, registered Hort Innovation members and industry representative bodies).
Evaluation of dried and table grape varieties (MT15026)
Status: New project
What’s it all about? Recently commenced, this project will deliver new grape varieties for both the table grape and dried grape industries. For table grapes, new distinctive varieties adapted to local conditions will enable Australia to differentiate its products in international markets, enhance export opportunities and increase domestic consumption.
What’s the latest update? For table grapes, the project has so far undertaken evaluation of seedless material established by the CSIRO in previous varietal work at Irymple, Victoria.
A new table grape planting, including 15 promising selections, has also been planted as grafted vines in Alice Springs, Northern Territory.
So far, evaluation of varieties has seen 54 table grape selections removed from multiplied plots for not meeting key criteria.
Australian table grape industry communications project (TG15008)
Status: New project, following on from Communicating with the Australian table grape industry (TG11000)
What’s it all about? This project will continue to maintain and improve communication to Australian table grape growers and other industry stakeholders. By keeping the industry up-to-date on R&D and marketing activities, news, events and other critical information, its ultimate goal is to help the industry tackle issues and to support decision-making and the uptake of new research and technologies.
What’s the latest update? A number of regular communication channels will continue to be produced and maintained by this project, including but not limited to:
- Quarterly magazine The Vine, distributed to industry stakeholders and also available online at www.australiangrapes.com.au/the-vine-magazine
- The Australian Table Grape Association (ATGA) website, www.australiangrapes.com.au
- ATGA social media channels including Facebook, Twitter (@ATGAHortnetwork) and YouTube
- Regular e-newsletters
- Industry forums and events.
A recent issue of The Vine
Export market access, maintenance, biosecurity and developing export markets for the Australian table grape industry (TG14000)
Status: Ongoing project
What’s it all about? This project aims to improve and maintain market access for Australian table grapes in overseas markets. A key focus is direct engagement with growers and exporters to develop export readiness and industry knowledge, and engagement with existing, new and potential markets and importers.
What’s the latest update? No new milestone report was due in the period since the last edition of Hortlink (Winter 2016). At the time of last reporting:
- There had been a number of initiatives on the grower side, including the publication of international statistics and general marketing intelligence in the table grape industry’s national magazine, The Vine, and continued work on resources including an online export manual.
- The Australian Table Grape Association (ATGA) had hosted a number of importer tours, with representatives from Japan, China, Thailand, Indonesia, Vietnam and the Philippines learning about the Australian table grape industry, observing the quality of the fruit, and building business-to-business relationships with leading growers, packers and exporters.
- Meetings with new and potential importers from the Middle East had been held, and trade shows attended in Dubai as well as South Korea and Japan. At the time of last reporting in Hortlink, trade development efforts with Japan had resulted in an increase of containers from 165 the previous year to over 500 this export season.
- The project had also seen coordination of activities including an on-shore cold verification audit from Thailand, hosting of a Korean inspector, and attendance at a variety of international workshops, trade fairs and meetings.
Other R&D projects of note…
» Cold disinfestation verification trials for table grape access to Japan (TG11013), which is due for completion in 2017.