Pest Type: Pest Vegetable Indoor Crop
Class: Arachnids – Arachnida
Subclass: Ticks – Acari
Row: Acariformi Mites – Acariformes
Family: spider mites – Tetranychidae
Dangerous pest of vegetables in greenhouses and greenhouses. Most often, it damages cucumbers, melon, watermelons, eggplant, peppers, beans, much less often – tomatoes.
The adult female tick has a wide oval body shape, about 0.4 mm long. Color depends on the condition of the feed plant and the period of the year. Females of the summer generations are gray or yellow-green with dark spots on the sides. Males are much smaller than females in size, with elongated and narrowed to the posterior end of the body.
The egg is spherical, transparent, with a greenish tint.
The larva has the shape of a hemisphere, with three pairs of legs. Nymphs are similar to adult ticks but somewhat smaller in size.
Under optimal conditions (air humidity 35-55%, temperature – 29-30 ° C), the female lays about 150 eggs. The period of embryonic development of the pest is 3-5 days. Larvae after three links, passing through the phases of prompt and deuterymphus, turn into adult ticks. The development of one generation of the pest, depending on hydrothermal conditions, takes from 7 to 25 days. A spider mite can produce up to 20 generations per year.
Ticks feed on the sap of plants under the cobwebs on the underside of the leaves. The first symptom of damage to plants by a tick is the appearance of individual bright spots on the leaves. In the case of intense damage, the leaves acquire light colors. Damaged leaves turn yellow, dry and fall; plants are inhibited, lagging behind in growth, which leads to a decrease in yield. Cucumber crop losses from spider mite damage can reach 40-60%.
Diapause: female pests are kept for a long time under plant debris, in the cracks of greenhouses, beehives, etc. Unlike the active forms, they are characterized by bright orange color, do not require food and do not breed, and are resistant to adverse environmental conditions. A significant part of such females can withstand temperatures up to -27 ° C for a long time, while active ticks die at -1 … -3 ° C. The main factor causing the appearance of diapause in females is the length of daylight, a certain influence is also exerted by the temperature and condition of the feed plant. At high air temperatures (above 25 ° C), the pest continues to develop regardless of the length of daylight hours.
After staying in the conditions of positive low temperatures (3-6 ° С) and with its further increase to 16-20 ° С, the females become active, feed and lay eggs. In the closed ground, the pest is distributed mainly with clothing of maintenance personnel, as well as with inventory and packaging.
In addition to the spider mite, the red-green mite causes significant damage to vegetables in greenhouses.
Protective measures. Maintaining the hydrothermal regimen optimal for cucumber plants. The use of a predatory tick of phytoseyulyus or biological preparations – phytoerm, Bicol, bitoxibacillin.