The most significant pest that appears on eggplant during the growing season is the Colorado potato beetle.
Colorado Potato Beetle
(lat. Leptinotarsa decemlineata)
Both the adult form (imago) and larvae feed on the leaves, which they can defoliate in a short time. Regular inspections are necessary, as the imago lays eggs on the underside of the leaf. The beetle has two generations per year, and typically the first generation’s attack is more severe and significant. The adult form overwinters in the soil. It is important to determine the correct timing for control. It is ineffective to apply insecticides when adult insects are emerging from the soil, except in cases of heavy infestation. The beetle is best controlled at the larval stage, which is the most sensitive to insecticides. When using insecticides, it is important to consider the pre-harvest interval if treatment is necessary during the fruiting period.
Insecticides that can be used are listed in the table.
| Insecticide Group | Active Ingredient |
|---|---|
| Organophosphates | These active ingredients are no longer used for controlling the Colorado potato beetle due to the beetle’s complete resistance to this group of insecticides caused by frequent use. |
| Pyrethroids | Resistance in the Colorado potato beetle |
| Carbamates | Resistance in the Colorado potato beetle |
| Neonicotinoids | Imidacloprid, acetamiprid |
| Nereistoxin derivatives | Resistance in the Colorado potato beetle |
| Development regulators | Teflubenzuron, lufenuron |
| Microbiological insecticides | Bacillus thuringiensis |
| Naturalytes | Spinosad |
For biological control against the Colorado potato beetle, elderberry leaf decoction is used. The scent of elderberry camouflages the smell of potatoes, making it difficult for the beetles searching for food to detect them. Mechanical control methods include hand-picking, which is suitable for smaller areas, while on larger areas, smaller or larger aspirators like DeVac are used.
When using chemical control against the Colorado potato beetle, it is important to note that the beetle has developed resistance to many insecticides. Uncontrolled use (or preparation of higher doses) increases resistance, thus reducing the spectrum of effective insecticides. Therefore, it is advisable to consult with a specialist when choosing insecticides and to strictly adhere to prescribed doses or concentrations, without increasing them.
Cutworms, wireworms, and mole crickets are soil pests that can cause damage by eating roots.
