Identification and control of the large-leaf boxwood spotted moth

Large-leaved boxwood (including varieties of phnom penh boxwood, silver edge boxwood, golden heart boxwood, etc.) is a very good hedge plant and background growing medium. It can usually be planted in a single plant in the flower mirror, or it can be planted in pieces, so it is widely used in landscaping. However, in recent years, the occurrence of the large-leaf boxwood moth has become more and more frequent, which seriously affects and its normal growth and ornamental value, so the prevention and control of large-leaf boxwood should arouse people's attention.

The large-leaf boxwood spotted moth belongs to the order Lepidoptera, family Zebraidae. It is found in Shanghai, Nanjing, Wuxi, Suzhou, Hangzhou, Wuhan, Lianyungang and Hefei.

harm

Large-leaved boxwood, silver-edged boxwood, golden-hearted holly spear, large flower spear, fufang vine and silk cotton wood. The larvae feed on the host leaves, and when severe occurs, the leaves are eaten up, affecting the normal growth of plants.

Identify features

imago:

Adults are 7 to 12 cm long, with antennae, cephalothorax and ventral end black, and most of the mid-thorax and abdomen are yellow. The forewings are pale grey , slightly transparent , 1/3 of the base light yellow. The hindwings are slightly paler in size than the forewings.

ovum:

oval.

larvae:

When mature, the body is about 15 mm long, the abdomen is yellow-green, and there are ∧ black markings on the dorsal plate of the front chest. There are 7 longitudinal bands on the back of the body, and there are hairs and short hairs on the surface of the body.

chrysalis:

Yellowish brown with 7 inconspicuous longitudinal stripes on the surface and 2 gluteal spines.

Habits of life

In eastern China, a generation occurs once a year, with eggs overwintering on annual branches. From the end of March to the beginning of April of the following year, the eggs hatch, and the young larvae cluster in the branches to feed on the new leaves, and then disperse the hazards with the growth of the insect age, and the amount of food increases sharply, and the leaves can be twisted and wrapped. The larvae sag when shaken slightly. From the end of April to the beginning of May, the larvae mature and pupate in a cocoon in shallow soil to pupate through the summer. In early November, the adults feather and lay eggs after mating, where they lay on the branches and overwinter with their eggs.

Prevention and control methods

Manual Removal:

Combine winter and spring pruning to shear the eggs. During the growth period, artificially pinch insect buds, remove insect leaves, concentrate on destruction, and catch adult insects; easy larvae to overwinter, they can be booby-trapped in dry base bundle grass before the larvae overwinter; in addition, because the overwintering eggs are mostly attached to the top of the fresh branches of the year, the green belt can be combined with pruning before winter every year to prevent, cut off the branches with eggs, and eliminate the eggs.

Pharmaceutical control:

Because the host of the large-leaf boxwood moth is mostly a green plant, the use of highly toxic pesticides should be prohibited. In recent years, we have carried out control experiments with high-efficiency and low-toxicity permethrin pesticides, and the results show that in the early stage of larval occurrence, that is, from the end of March to the beginning of April every year, 5% enemy killing emulsion or 5% kung fu emulsion 3000 times dilution is applied, and the prevention and control effect is about 98% in the center of the occurrence and the surrounding branches; Other permethrin pesticides such as 20% exterminated emulsion, 20% rapid exciter butyl emulsion, etc., can also achieve a good control effect.