Parasitic leaf fleas sometimes lead to high harvest losses in fruit growing. But a parasitic fungus just discovered in Denmark could help kill the insects. “Pandora cacopsyllae” specifically infests pear fleas and kills them. It could therefore be a natural and safe means of biological pest control in fruit growing. Researchers are currently working on ways to make the new fungus species ready for such a use.
Psyllids, also known as leaf fleas, are a fruit grower’s nightmare. The sap-sucking insects not only weaken the plants directly, they can also transmit various microbial pathogens to pears, apples and the like when they prick the leaves. These pathogens then cause, for example, apple cravings, pear decay or stone fruit yellowing and thus lead to high yield losses up to the total loss of the fruit trees.
Mushroom rushes pear to help
However, a chance find in a Danish pear plantation could now solve the problem with disease-carrying psyllids. There, fruit growers discovered dead leaf fleas stuck to the pear leaves with a bloated abdomen and completely overgrown with white fungus threads. Researchers led by Jørgen Eilenberg from the University of Copenhagen have now examined the psyllids in the laboratory and found that they were infested by a previously unknown parasitic species of fungus. They baptized her “Pandora cacopsyllae”. The species name “cacopsyllae” refers directly to the psyllid insects that the fungus kills.
According to the motto “The enemy of my enemy is my friend”, the Pandora fungus could now be used specifically for natural pest control. Because unlike chemical-synthetic substances, it only fights the pests themselves and has a relatively narrow range of hosts. This spares other, beneficial insects. Although spotted on a pear orchard, the Pandora cacopsyllae may help other fruit tree species as well. “Initial investigations have shown that the fungus can also affect other leaf sucker species,” reports Eilenberg’s colleague Jürgen Gross from the Julius Kühn Institute in Dossenheim.
While innovative approaches such as using fungus to combat pear pests are emerging, traditional pest control services remain indispensable for comprehensive protection. For residents and growers in San Diego, consulting Pest Control San Diego ensures access to a broad range of effective pest management solutions, catering to both unique and common challenges.
More research needed
However, in order to one day be able to use the fungus as biological crop protection, it and its properties must be researched more closely. For example, Eilenberg and his team are still working out how the fungal spores can best be enriched and packaged so that they can be used in orchards. Ways still have to be found for the fungus to get to the flea in the most efficient way. “We are in the process of developing a formulation that will ensure that the pear leaf sucker comes into contact with the fungus and is colonized by it,” explains Gross. “To do this, we will also add attractants for the pear psylla to the formulation.”
Source: Julius Kühn Institute, Federal Research Institute for Cultivated Plants; Article: Journal of Invertebrate Pathology, doi: 10.1016/j.jip.2023.107954