Fight against flea beetles
What are flea beetles?
Flea beetles are small beetles belonging to the genus Phyllotreta, psylliodes. They pierce the cotyledons and foliage with numerous round holes, partially destroying them. This slows plant growth and devalues the products. Very small, they measure between 1.5 and 5 mm long and are black, blue, or green with metallic reflections. Some have yellow bands. They have highly developed hind legs that allow them to jump when disturbed. This characteristic is the origin of their nickname, "earth fleas."
The adults feed on the leaves while the larvae, which are discreet, prefer the roots, but these do not seem to affect the growth of the plant.
What conditions favor the arrival of flea beetles?
Periods of heat and drought are favorable for flea beetles. They are particularly active from May to August.
Flea beetles hibernate under leaves, debris, or in the soil and emerge from their hibernation period in May. Initially attracted to wild plants, they soon move towards vegetable garden crops. Once the host plant has been located, the adults feed on the leaves of the host plant for several weeks before the females lay about a hundred eggs at the base of the plant. The larvae appear about 2 weeks later and feed on the roots for 15 days before reaching the pupal stage and finally emerging as an adult about twelve days later.
Which plants are mainly attacked by flea beetles?
They mainly attack plants belonging to the Brassicaceae family such as turnips, radishes, arugula, cabbages, rhubarb, horseradish, etc. and some other vegetable plants such as beets and leeks, potatoes, corn, strawberries, etc. Seedlings and young shoots are particularly sensitive.
How to fight flea beetles?
Water the foliage regularly and keep the soil moist.
Regular hoeing at the base of the plants will disturb the eggs.
Sprinkle fresh pieces of repellent plants such as rosemary over the crop to be protected.
Place an insect net as soon as you emerge or transplant.
Finally, plant pyrethrum is a solution for curative treatment if crops have been invaded.
