Privet is an evergreen tree of the genus Privet, dense foliage, neat tree shape, good drought tolerance, water and moisture tolerance, warm and humid climate, deep-rooted tree species, with well-developed roots, fast growth, strong germination, pruning resistance, but not barrenness. It is one of the commonly used tree species in landscaping.
Ash borer is one of the most common pests in Privets and belongs to the order Homoptera, Wax Bug family. Widely distributed in China. It is harmful to longleaf privets, privets, Japanese privets, parsley ash, white ash, water wax, cedar, citrus, camellia and grapefruit. Adults and nymphs suck on the host branches as a pest, resulting in weak trees, slow growth, and even dead branches.
Morphological characteristics
Female adults are wingless, 1.5 mm long, and can grow to 15 mm during the spawning period; the back is raised before fertilization, mussel shell-like, and after fertilization, the worm body expands into a hemispherical shape, and the shell is relatively hard, about 10 mm long and about 7 mm high. Yellowish brown, light red to reddish brown, scattered light black spots, yellow-green abdomen. There are 6 antennae, of which section 3 is the longest. The male adult is about 2 mm long, yellowish brown, with a wingspan of 5 mm, transparent wings with an iridescent luster, and a tail with 2" > white wax filaments. The eggs are mostly oblong-oval, about 0.4 mm long, 0.25 mm wide, the female eggs are reddish-brown, and the male eggs are light yellow. Nymphs are yellowish brown and ovoid. The average body length is 0.70mm wide.
Habits of life
The insect occurs in 1 generation a year, with fertilized female adults overwintering on the branches. In March of the following year, the female adult worms expand their eggs and begin to lay eggs in early April, with an egg period of about 7 days. The nymph stage of the ash borer in Shanghai coincides with the flowering stage of Privet leaflet. The hatching nymphs parasitize on the leaves near the mother, and after 2 instars, they are transferred to the branches for pests, and the male nymphs secrete a large amount of white wax after fixation, covering the worm body and branches, and in severe cases, the entire branches are white rod-shaped. In early October, the male adults feathered and died after mating. The adult fertilized female grows up and overwinters as the temperature drops. According to reports, the Dalian area is the peak of nymph hatching in late June, there is no wintering phenomenon in Kunming area, and the nymphs begin to hatch in mid-March. Continuous high temperatures and droughts or continuous rains can cause a large number of nymph deaths.
integrated control
1. Strengthen conservation management: strengthen the investigation of insect conditions, timely prune the insect branches and over-dense branches that are seriously damaged, and when there are more occurrences, the insect body can be removed with a brush.
2. Protect and utilize natural enemies: such as flower-winged jumping wasps, aphid-eating wasps, ladybugs and predatory mites.
3, pharmaceutical control: winter or early spring trees before germination can be used 5 baumedo stone sulfur compound liquid spray control; before the male insects form wax in the growing season, you can choose to kill the insect emulsion 1000-15000 times liquid or 40% rapid oyster gram emulsion 1000 ~ 1500 times liquid, 10% imidacloprid wettable powder 1000 times liquid and other spray control. The berserk insect has a special effect on the mesmeria, which is infused with a highly effective penetration agent that can be killed even if the mesosome has formed.
