Pest Type: Cabbage Pest
Row: Equine – Homoptera
Family: Aphids – Aphididae
It is found everywhere. Damages cabbage, radish, swede, turnips, and other cabbage plants.
A wingless parthenogenetic female 1.8–2.0 mm in size, ovoid, pale green, covered with white-gray pollen; the chairman is light brown, with brown transverse stripes on the abdomen from above, black eyes, brown legs, antennae 5-6 segments; the tubes are cylindrical, shorter than the conical tail. The winged female is 1.5-2.2 mm in size, the body is covered with gray pollen, the abdomen is yellow-green with brown transverse stripes, the head, antennae, chest, and legs are brown. Amphigone female, 1.7-2.0 mm in size, light, without wax pollen; tubules, tail, the sixth segment of antennae and legs light brown.
Male winged, 1.4-1.8 mm long, similar to winged female; black antennae, brownish tubes, yellowtail. The egg is 0.5 mm, elongated-oval, light black.
The view is non-migratory. Eggs hibernate on the ears of cabbage, testes, and weeds from the cabbage family. Females can winter in the south. In April, at an average daily air temperature of 11-13 ° C, larvae hatch, which after 10-16 days, after four molts, turn into adult wingless females that, without fertilization, give birth to 40-50 larvae.
During the first half of summer, cabbage aphid develops on the same plants on which the eggs hibernated. At the end of May-June, winged females appear that fly over to cabbage and other cabbage plants, where larvae are born without fertilization. During the growing season, aphids give from 8-10 to 16 generations. In the fall, females appear that give birth to larvae turn into wingless females and winged males of the amphibole generation. Fertilized females lay 2-4 eggs, which remain until spring.
Adults and aphid larvae inject saliva enzymes into the plant and suck out the juice. The plant decreases the amount of chlorophyll, sugars, and vitamins. Damaged leaves turn yellow, curl and dry. The development of the head of cabbage stops. On the testes, flowering shoots, and the stems of the apices become black-purple, dry out and do not form seeds. Aphids are especially numerous and harmful in the second half of summer. In the south of Russia in case of mass reproduction of the pest, the yield loss of late cabbage varieties reaches 65-90%.
Stormy aphids and cold weather negatively affect the development of aphids. The number of pests is reduced by predators, parasites and diseases. About 100 species of parasites and aphid predators have been identified. The main predators are representatives of families and others. There is a death of the pest from entomophile fungi.
Protective measures. Destruction of post-harvest residues (double disking) and weeds from the cabbage family. Deep autumnal plowing of fields with the goal of plowing plant debris. Placing nectarous cabbage (dill, carrots, phacelia, etc.) near sites for entomophagous lures. In the case of the identification of the first foci of the pest and the number of 150 individuals per 10 plants, it is advisable to use insecticides. However, before conducting chemical treatments, species should be counted in pest colonies. With a pest: entomophagy ratio of 20: 1, insecticides are not used.