Strawberry fields forever? Not if the tiny Asian fly invading the UK succeeds at wiping out all the soft fruit
- A 2mm Asian fly could devastate the UK fruit industry, experts have warned
- The fly has caused 80 per cent loss of crop yields in some parts of the U.S.
- Scientists are appealing to the public to help map its outbreak in Britain
A tiny fly from Asia could wipe out British strawberries and other soft fruit, scientists have warned.
At just 2mm long, Drosophila suzukii uses powerful saw like jaws to break through the skins of ripe fruit and deposit its young inside.
The maggots then hatch, and eat through strawberries, raspberries, blueberries and other soft fruit, causing it to rot.
Scientists are trying to establish how widespread it is in Britain amidst fears it could devastate the local market and drive prices skyhigh.
Britain's fruit industry is on red alert after the pest was spotted in Kent last year. It has proved impossible to eradicate elsewhere in the world
The new pest has already spread rapidly through the USA and Italy since 2008, and was first spotted in the UK last year. The state of California alone lost $300 million worth of strawberry crops the year the insect was detected.
Dr Ezio Rosato, of the University of Leicester, said: 'Drosophila suzukii are different from the common fruit flies found in the UK. They are able to use their enormous ovipositor to break into fresh fruit and lay their eggs.
'This creates trouble. If you are a fruit grower and have little maggots growing in your fruit, it won’t be marketable. The animal has already had a huge effect on the soft fruit market in the USA and Italy.
'We want to limit the impact the animal will have in the UK. We want to develop a genetic system to control the spread of the animal - rather than relying on pesticides or introducing new predators.'
Slightly larger than common fruit flies which only lay eggs in rotten fruit, the males are easy to spot thanks to the dark dots on each wing. Also known as the spotted wing Drosophila, it originated in south east Asia.
The tiny Asian fruit fly - the spotted wing vinegar fly known as drosophila suzukii - devastates soft fruit crops
Dr Rosato and colleagues are appealing to the public to help map out its invasion after some areas in the USA experienced 80 per cent loss of crop yields.
They are hoping to find a biological solution to prevent the same happening in the UK.
THE ASIAN FRUIT FLY
The fly, known as drosophila suzukii,
originated in south-east Asia but reached the US in 2008, Italy in 2009
and Canada, Russia, France and Spain in 2010.
Adult flies are brownish-yellow with black bands on the abdomen, up to 3mm long with bright red eyes.
Females can lay up to 60 eggs per day and 13 generations of the insect can hatch in a single year.
The plan is to genetically modify male fruit flies in order to ‘switch off’ genes essential for the development of the embryo into a maggot.
The switch does not involve toxic substances or foreign genes. Instead, it exploits a natural process of gene regulation.
When the modified flies are released into the wild and mate with females offspring will not develop into larvae, preventing the species from reproducing further.
The approach removes the need to use pesticides or introduce new predators to kill the insects, both of which can have unintended consequences for other species and the environment.
They are asking for the help of budding ‘citizen scientists’ to set traps for the flies around the country, so the scientists can see where the flies have already made themselves at home.
Anyone can take a recycled plastic bottle, cut small holes in the sides and put a small amount of cider vinegar in before hanging it from a tree or the fence in their garden.
Fruit flies and other insects in the area will be attracted by the vinegar, and will enter by the small holes but will drown in the liquid at the bottom.
People can then send the liquid back to the scientists who can check to see if any Drosophila suzukii made their way into the bottle. This will help build up a map of where the insects are appearing around the country.
More than 50 people have already signed up to take part with traps set in Leicestershire, Derbyshire and Yorkshire.
Dr Rosato added: 'Having the public involved in this project is really useful as it will help us have an idea of where the animal already is in the country. It is also a really good way of involving people in science, and I think people really appreciate having the chance to take part.'