As part of the educational 'Discovery Zone', CABI's display will include invasive alien weeds - plants that have been moved from their native habitat to a new one, with no natural enemies like diseases and insects to keep them in check, enabling them to spread and cause problems.
Invasive non-native species are estimated to cost the British economy £1.7 billion a year. Plants are particularly troublesome and, once out of control, they can damage delicate ecosystems and even property. The exhibit demonstrates the plants' impact on the environment and infrastructure, including Japanese knotweed on property prices, buddleia on the railway and Himalayan balsam on riversides.
Alongside the invasive weeds, CABI will demonstrate biological control in action - a sustainable alternative method for controlling invasive species. This approach uses natural enemies from the native range of the invasive species, which are rigorously tested to ensure they pose no threat to the new ecosystem and represent a long-term and effective management option.
Live displays will feature sap-sucking psyllids feeding on Japanese knotweed and weevils eating the invasive alien water weed, Azolla (Azolla filiculoides). Visitors will also be able to use a microscope with live screen displays to learn more about CABI's research.
CABI invasives coordinator Dick Shaw said: "The Chelsea Flower Show is a fantastic opportunity to show the public how we can apply science to control some of the most damaging invasive weeds."
Since 2003, CABI has been researching a sustainable long-term biocontrol option for this Japanese knotweed. A sap-sucking psyllid, Aphalara itadori - an aphid-like insect about 2mm long - was identified as a possible solution.
Lab testing showed it poses no risk to native species, crops or wildlife, and approval was given for CABI to release the insect at selected sites. CABI is now focussing on getting it established and spreading in the field. There is evidence that a new approach has improved the insect's ability to overwinter.
CABI is also investigating a biocontrol solution to target buddleia infestations along railway lines - the application of wood-rotting fungus such as Chondrostereum purpureum to a freshly cut stump of the plant. The approach should provide a more effective and environmentally friendly alternative to chemical herbicides, and is already a well-established practice in the United States.
In 2006, CABI was asked by Defra, the Environment Agency and the Scottish Government to help control Himalayan balsam by finding a natural enemy. CABI identified the rust fungus Puccinia komarovii var. glanduliferae as the most promising biocontrol agent, and carried out research to ensure it was reliable, effective and safe. In 2014, permission was granted to release it at selected sites. In 2016-17, there was evidence of spores successfully overwintering. CABI plans to make further releases this year across the UK.