Elaeagnus angustifolia

TriozamagnisetosaLog. Homoptera, Psyllidae.

Host Elaeagnus angustifolia, jujube.

Damage characteristics: adult and nymph prick and suck the sap of buds, twigs and leaves, buds often die when damaged, damaged leaves often curl on the back, serious branches die, weaken tree vigor, a large number of flowers and fruits drop.

Morphological characteristics Adult body length 2.5~3.4 mm, dark green to yellow. Compound eyes large, prominent, auburn. Antennas filiform 10-node, tip 2-node black, tip 2-hairy. Prothorax plate "bow" shape, before, after dark brown, there are 2 brown longitudinal band. There are 5 brown longitudinal stripes in scutellum. The wings are colorless and transparent, and the front wings have three longitudinal veins each divided into 2 forks. The posterior margin of each abdominal segment is dark brown. The egg is about 0.3 mm long, slightly spindle-shaped, with a short appendage, pale yellow. The nymph is 2.3 - 3.3 mm long, yellow-white to gray-green, flat oval, and covered with white spongy matter.

Life History and Habits: One generation per year, overwintering as adults in deciduous leaves, weeds, bark crevices and withered leaves on trunk. The following March, when the temperature reaches 6℃, the activity begins. From early April to early June, mating and laying eggs are mostly in the morning and evening. In the germination stage, eggs are laid on buds, several grains are together, and most of them are laid on the back of leaves after unfolding. One end of eggs is inserted into mesophyll. Incubation begins in early May and reaches its peak in late May. The nymph stage is 45~50 days, and the 5th instar nymph is the most harmful. When the population density is high, the nectar discharged makes the branches and leaves shine. From mid-June to July. The adults live for about one year. They gather on the back of leaves during the day and overwinter when the temperature reaches below 0℃ in late October. Natural enemies are flower bugs, ladybugs, lacewings, thrips and so on.

Control methods (1) after autumn to remove orchard leaves, weeds, centralized treatment. (2) Chemical control, refer to Chinese pear psyllid. The suitable period for prevention and control is at the end of overwintering.