Biological control with insecticidal fungi

New applications of entomopathogenic fungi against soil pests such as crane fly larvae and grubs

Combating grubs

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Grubs are larvae of the cockchafer. In addition to the roots of grass and many herbs, they feed off the roots of ligneous plants. This causes major damage in grasslands and tree nurseries and on golf courses.

Combating crane fly larvae

Crane fly larvae pull young plants (and especially grass) into the soil to eat them.

In large numbers they can cause major damage to meadows and sometimes even potted plants.

(Photo: Koppert Biological Systems)

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Entomopathogenic fungi

Entomopathogenic fungi can kill insects and are therefore deployed in biological control in agriculture and horticulture.

Right: a grub affected by

entomopathogenic fungi.

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Collecting fungi

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To find entomopathogenic fungi we collected plants with root ball from extensively managed meadows in Switzerland. These meadows offer a wide variety of plant species. It was shown that 76% of the collected plants contained entomopathogenic fungi. The fungi were collected from the root environment of the plants.

Collecting fungi

Each plant variety was dug out with the root ball and transported in individual bags for research into the presence of entomopathogenic fungi.

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Isolated entomopathogenic fungi

Various entomopathogenic fungi were isolated from the root ball of the herbs in Switzerland (see images above). Five fungi isolates were shown to effectively combat grubs and crane fly larvae.

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Yorkshire fog (Holcus lanatus)

 

Meadow sage (Salvia pratensis)

 

Upright brome (Bromus erectus)

 

Brown knapweed (Cntaurea jacea)

 

Common dandelion (Taraxacum officinale)

 

English plantain (Plantago lanceolata)

 

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Results of combating grubs

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Result of combating crane fly larvae

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Combating cabbage fly in radish

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The most effective isolates were also tested against the cabbage fly. The image above shows a test setup with radish plants infected with cabbage fly eggs and treated with various entomopathogenic fungus isolates.

Combating cabbage fly in radishThe plant on the left has been entirely devoured by the cabbage fly. The left jar shows adult cabbage flies.

The plant on the right remained healthy due to protection from one of the tested fungus isolates.

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Combating cabbage fly in radish

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