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Morphological Characteristics and Damage of the Jujube Turtle Wax Scale

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The jujube turtle wax scale belongs to the order Homoptera, family Coccidae, and is also known as the Japanese turtle wax scale or jujube louse. The adult is pale red, with a body length of 0.9 mm, black compound eyes and whip-like antennae. The wings are white and transparent, with two main veins. The female is oval, resembling a turtle shell; the egg is oval, pale yellow at first and purplish red later; the nymph is oval and pale red, and in its early stage spreads by wind before soon settling on leaves to cause damage; the pupa, only the male pupates beneath the scale cover. The pupa is oval. The insect, as nymphs and female adults, fixes itself on branches, leaves and fruit to suck sap, and its excretions induce

The jujube turtle wax scale belongs to the order Homoptera, family Coccidae, and is also known as the Japanese turtle wax scale or jujube louse. The adult is pale red, with a body length of 0.9 mm, black compound eyes and whip-like antennae. The wings are white and transparent, with two main veins. The female is oval, resembling a turtle shell; the egg is oval, pale yellow at first and purplish red later; the nymph is oval and pale red, and in its early stage spreads by wind before soon settling on leaves to cause damage; the pupa, only the male pupates beneath the scale cover. The pupa is oval.

The insect, as nymphs and female adults, fixes itself on branches, leaves and fruit to suck sap, and its excretions induce the spread of sooty mould, covering branches, leaves and fruit with black mould that directly affects photosynthesis, causing heavy fruit drop and decline of tree vigour, resulting not only in reduced yield in the current year but also affecting tree vigour for several years. Therefore, this insect is one of the main pests of jujube trees.

Life Habits and Control Methods of the Jujube Turtle Wax Scale

The insect has one generation a year and overwinters as mated female adults on 1-2 year old branches. In April of the following year, when the tree begins to grow, it starts piercing and sucking sap, enlarging its body. It begins laying eggs in mid-May, and a single female can lay up to 3,900 eggs. Early July is the peak period of egg hatching. Males begin to pupate in mid-August. After emergence, the male adult crawls out of the wax cover and flies about during the day, searching for females to mate. Male adults are phototactic. After mating, the female adult moves from the leaves to the branches, and especially likes to settle on new jujube shoots to cause damage.

Control methods:

(1) In winter, in conjunction with pruning, cut off infested branches and burn them in a centralized manner.

(2) Protect natural enemies, such as the ectoparasitic insect Scutellista cyanea, the endoparasitic insect Tetrastichus, and also ladybirds and predatory insects.

(3) Chemical control, for example, spraying 50% wettable carbaryl at 500 times dilution, or 25% quinalphos emulsifiable concentrate at 1000-2000 times dilution, at the peak of nymph hatching.

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