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Aphalara itadori - Tiny insect takes on Japanese knotweed

Aphalara itadori - Tiny Insect Takes on Japanese Knotweed

Scientists at CABI have made a significant discovery in the battle against Japanese Knotweed, a notorious invasive plant species.

They have found a tiny insect called Aphalara itadori, belonging to the psyllid family, which has shown promise in weakening the plant's ability to spread. For those in the know this is relatively old news but the topic has recently resurfaced and there's a little more science and fact behind the discovery of these jumping, munching nats ‘taking on Japanese Knotweed’.

According to reports, Aphalara itadori is particularly effective against the most aggressive type of Japanese Knotweed found in Britain. This discovery offers a natural and potentially sustainable solution to control the spread of this problematic weed.

Controlling Japanese Knotweed has been a considerable challenge, with estimated nationwide efforts in the UK costing over £1.56 billion, mainly relying on chemical and mechanical methods. However, the introduction of psyllids presents a promising alternative.

Psyllids were first introduced into the wild in Britain in 2011, but initially struggled to survive British winters. To address this issue, researchers identified a new psyllid variant from Japan, which proved to be more resilient to British weather conditions.

Trials conducted since 2019 have shown promising results, with the psyllids effectively damaging Bohemian knotweed, a more aggressive type of the plant commonly found in Europe. Despite initial challenges, scientists remain optimistic about the potential of this biological control method.

Dr. Dick Shaw, an entomologist and senior regional director at CABI, expressed determination in continuing the research efforts, stating that they are exploring strategies such as selective breeding to enhance the effectiveness of the psyllids.

Japanese Knotweed, introduced to Britain during the Victorian era for ornamental and soil stabilisation purposes, has since become a significant environmental concern due to its rapid spread and destructive impact on native ecosystems.


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