Xylella: understanding more about a potential threat

Spittle on cleavers Galium aparine
Image: Alan Stewart, Univ. Sussex

There have been reports in the media recently about Xylella fastidiosa, a plant pathogen which has been described by the European Commission as “one of the most dangerous plant bacteria worldwide, causing a variety of diseases, with huge economic impact for agriculture, public gardens and the environment.”

Xylella is not present in the UK and for many years the bacterium was restricted to the Americas where it caused serious disease outbreaks in crops such as citrus, coffee, grapevine and peach. 

However in 2013, Xylella was identified in diseased olive trees in the south of Italy and has gone on to kill millions of trees. 

Spittle on lavender
Image: Alan Stewart, Univ. Sussex

The disease is transmitted by insects such as leaf-hoppers and frog-hoppers/ spittlebugs - which do occur in the UK - so if Xylella-infected plants were imported into this country, it could be spread by these insects with very serious consequences. That's why our colleagues at the John Innes Centre are leading on research into Xylella, with a project called BRIGIT - you can find out more about the project here. 

Chris Pollard of Forest Research said "“Botanists submitting records of spittle seen whilst out recording plants would be fantastic to help us better understand how these insect vectors behave.”

Here are the sites to use for recording the spittle and potential Xylella infections:

To record spittle or froghoppers on plants: https://www.brc.ac.uk/irecord/xylem-feeding-insects

General info on plants that might be affected by Xylella, including pictures of symptoms: https://www.rhs.org.uk/advice/profile?pid=1037

To submit a record that could be Xylella: https://treealert.forestresearch.gov.uk/index.php/report?line=general

Submitting records of spittle is quick and easy to do and will help researchers develop a better understanding of the factors that contribute to the likelihood of Xylella being introduced and spread in the UK.