Bees have always been busy. But who knew 'detect plant viruses' was on their to-do list? Our new study has confirmed this extra benefit to their foraging and pollen collection.
A hive of activity
Our scientist Dr John Roberts[Link will open in a new window] has worked on bee health and biosecurity[Link will open in a new window] for more than a decade. When checking hives for bee viruses, he noticed his DNA testing was also picking up plant viruses.
"The concept of using bees for plant pest surveillance came about when we realised just how much crop information we could tell from the pollen they collected in their honey-making and pollination tasks,” John says.
"Pollen is often a record of what pathogens are affecting the plants. By looking at pollen DNA, we can identify plant pathogens in that particular crop or orchard."
It's all in the DNA
Advances in high throughput DNA sequencing, which decodes DNA faster by analysing multiple smaller pieces of DNA at the same time, have improved virus detection capability.
John says bees are the perfect plant samplers. They go from flower to flower collecting pollen. In the process, they make a representative sample from a large number of plants across a large area.
“A typical orchard would have literally tens of thousands of bees at work up in the canopy," he says.
“Their foraging and sampling behaviour, combined with high throughput testing of pollen in hives, makes it possible to test a large number of samples representing a wide area for multiple viral plant pathogens."
Detecting plant viruses
We conducted a study into this opportunity in collaboration with The University of Queensland[Link will open in a new window] and South Africa’s Agricultural Research Council[Link will open in a new window], and supported by Hort Innovation[Link will open in a new window]. It showed we can use bees to detect and monitor plant viruses, specifically avocado sunblotch viroid in orchards.
This honey bee surveillance method is also capable of providing earlier detection of plant viruses than conventional monitoring methods. Early detection of plant viruses is critical for effective plant biosecurity as it enables growers to respond quickly and limit their spread.
It’s particularly important in this case. We need to demonstrate to our export trading partners that our avocado orchards are free from avocado sublotch vidoid.
To infinity and bee-yond
"Now that we’ve proven this concept, we hope to use bees for annual monitoring of our avocado orchards during flowering and pollination," John says.
"It’s also a powerful cross industry biosecurity monitoring tool of the future. It can provide surveillance for multiple plant pathogens simultaneously, including pathogens affecting honey bees themselves."
You could say it's the ultimate sweet spot of honey bee sampling, advanced DNA analysis, crop pollination and a delicious harvest!
The research[Link will open in a new window] was funded by Hort Innovation and supported by the Queensland Department of Agriculture and Fisheries[Link will open in a new window].