This is a final research report from Hort Innovation’s historical archives. Please note that as these reports may date back as far as the 1990s, the content and recommendations within them may be superseded by more recent research.

What was it all about?

The Australian custard apple industry was a well-led, organised industry. It was distributed from the Atherton Tableland in the north to the Alstonville Plateau in the south, and there were also custard apple growers in the Northern Territory and Western Australia.

The industry was breeding new varieties of custard apple at the time for different environments, and these varieties were being tested in seven geographically separated areas. Some of these varieties had already been commercialised and were available to commercial custard apple growers. In addition, new rootstocks onto which the varieties were grafted were being sourced from Taiwan and Brazil, and were also being developed through the breeding program.

The breeding program was located at the Maroochy Research Station in southeast Queensland. Approximately 13 000 new lines were bred and planted into the field. A small proportion of these crosses were assessed for fruiting performance, disease resistance and eating quality. The remainder would be tested as the plants mature.

New soft chemicals were developed for pest and disease control. The fungicides were developed from naturally occurring fungi, and successful insecticides for scale and mealybug control were developed from mineral oils. In addition, predatory ladybirds could be purchased off the shelf for control of some serious pests of custard apple, such as scale and mealybug.

There was considerable potential to expand sales of custard apple into domestic, as well as, export markets. Asian cultures in particular liked custard apple, and there were significant markets in southeast Asia for custard apple. Exports of custard apple to Hong Kong and Singapore were a regular occurrence, and the large fruit produced by Australian custard apple growers commanded a premium price in these counties.

While there were some biosecurity barriers in place, the industry was working on developing new ways of fruit access into other Asian countries.