Pest Type: Cabbage Pest
Row: Lepidoptera – Lepidoptera
Family: Sickroot Moth – Plutellidae
It is found everywhere. The zone of high severity covers forest-steppe and steppe areas. It damages cabbage, radish, radish, turnip, canola, turnip, mustard, swede, horseradish and other plants of the cabbage family.
The butterfly has a wingspan of 12-17 mm, the front wings are narrow, gray-brown, along the rear edge there is a white or yellowish stripe, which, when composing the wings, forms a diamond-shaped pattern; hind wings silver-gray with a long fringe; antennae with 35–37 segments, at rest elongated forward. The egg is 0.4-0.5 mm in size, oval, somewhat flattened, pale green. The caterpillar is 8-11 mm, green, with small black spots and rare black setae, its body is somewhat spindle-shaped. The pupa is 6–9 mm, pale green, later darkens. Cocoon size 8 mm, spindle-shaped, silver-white.
Pupa overwinter; in the south, partially butterfly on weeds and plant debris. The flight of adults occurs in April-early May. Butterflies with fully developed genitals come out and immediately begin to mate.
The female lays eggs, one at a time or in small groups (2-4), on the underside of leaves or cuttings. Fertility is 70-165 eggs. Caterpillars hatch after 3-7 days, bite into the parenchyma of the leaves and make short passages in them. After 3-4 days, the caterpillars leave the mines and are located mainly on the underside of the leaf, forming thin spider web nests in which the first molt occurs. Subsequently, the caterpillars gnaw out small sections of leaf tissue without affecting the upper cuticle. Such damage has the form of “windows”. Caterpillars are very mobile, they spin quickly and fall from the leaf, hanging on a spider web.
The lower temperature threshold for the development of eggs is 8 ° C, of caterpillars -5.4 ° C, of pupae-9 ° C. The sum of the effective temperatures for the full cycle of development of one generation is 380-416 ° C.
Caterpillars develop 9-15 days and pupate in a white translucent spider web cocoon. After 7-14 days, butterflies of the second generation come out. Cabbage moth butterflies live on average 17-30 days. Fly at dusk, eat on the flowers of cabbage plants. In the north cabbage moth has 2-3 generations, in the south – 4-5. Generation is not clearly delineated, therefore, the pest is found on plants at different stages of development at the same time. The full cycle of development of cabbage moth lasts 25-35 days. In cabbage, damage in the phase of ring formation (“hearts”) is dangerous.
102 entomophagous cabbage moths are known. Trichogramma everesceus Week parasitizes in eggs, the main parasites of caterpillars are Apanteles patella Kurd et al. Caterpillars and pupae are affected by fungal and bacterial diseases.
Protective measures. Destruction of plant debris on which cabbage moth hibernates. Deep autumnal plowing. Weed control from the cabbage family. When 10% of the plants are populated and the number exceeds 4-5 caterpillars per plant, it is advisable to spray with biological products or insecticides.