Feltiella acarisuga

Feltiella acarisuga is a predatory midge. The midge is one of the most effective and widely spread natural enemies of spider mites. Feltiella acarisuga is applied in the complex defense programs of crops in glass-covered ground against different biotypes of spider mites. The best results of predator application are achieved on the cucumber, the tomato, the eggplant, and also on the rose and the gerbera.

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The body of an adult individual is small, fragile, pink-brown. The life span of the adult predators is 4–5 days. The adult feeds mainly on the sugary excretions of pests. The female lays eggs in the colonies of spider mites on the underside of a leaf. The female lays on an average 30 eggs. The larva is orange-brown. During growth its length changes from 0.2 to 2 mm and its diameter does from 0.2 to 0.4 mm. The duration of larvae stage is 5–10 days dependently on hydrothermal conditions and food availability. It pierces the body of a prey and eats away the contents of a mite. In the feeding process of the acariphage its larva is able to kill 15 adult individuals, 30 larvae of different stages and 80 eggs of the pest per day.

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The optimum hydrothermal conditions are a temperature of about 20°C and a relative humidity of 70–80%. It is not recommended to use Feltiella acarisuga for prophylactic because the deficit of food may cause the death of the predator. In the conditions of short daylight period the predator is not very effective because it may enter diapause. Invasions are realized by means of inundation releasing every week 250–500 individuals of acariphage per ha. If necessary the rate of invasion is increased.

Advantages

  • application on many of crops including tomatoes;
  • excellent search abilities;
  • the elimination of all the stages of the pest;
  • the easy discovering of larvae under monitoring.