Evaluation of the sugar flotation method for testing cherries for Queensland fruit fly (CY14009)

What was it all about?

Queensland fruit fly and Mediterranean fruit fly can cause considerable damage to cherry fruit and potentially restrict access to some export markets. A fast but robust test is needed to find any fruit fly infestation along the supply chain of the host commodity before it reaches its target market.

Various flotation methods have been used to separate fruit flies from their host fruit. Flotation methods use density differences between insects and solutions of various salts and sugars to dislodge and float insects away from fruit. The brown sugar flotation procedure has been recommended for use on farm or for interstate and international trade in the USA, Canada and Mexico. 

This project set out to investigate if flotation methods can help to detect the presence of the main fruit fly species affecting Australian cherries.

The research found the brown sugar flotation test was effective for finding fruit flies, particularly when used with the machine fruit crushing system, rather than hand crushing of fruit. This approach was then further investigated through other Hort Innovation Cherry Fund work.