Identification and Control Methods of the Impatiens Hawk Moth

The scientific name of the impatiens hawk moth is Deilephila elpenor lewisil Butler. It is a major pest of impatiens and is distributed in Northeast, North, East and Northwest China. Besides impatiens, its host plants also include autumn orchids, herbaceous flowers and others.

Damage characteristics: this insect feeds on leaves in the larval stage, affecting the growth and development of the plant, and is a major pest of impatiens.

Morphological characteristics

The adult body length is 33-40 mm, and the wingspan is 55-70 mm. The wings and body are red with a yellow-green sheen. There are 2 longitudinal red bands on both sides of the head and on the back, and the dorsal line and both sides of the abdomen are red. The forewings are pea green, the half of the hindwings near the base is dark brown, and the half near the outer margin is red.

The larva is 75-80 mm long. The head and prothorax are relatively small, the metathorax is swollen, and the body is densely covered with a reticulate pattern. The thorax is light brown and scale-like. The thoracic legs are yellow-brown. There is 1 pair of dark brown eye-like markings on the dorsum of the first to second abdominal segments. In the middle of the markings there is a crescent-shaped, light brown spot. The spot is surrounded by white. Each segment has a light-colored transverse line on the dorsum, and the sides of the body have light-colored diagonal lines. The ventral surface of the abdomen is dark brown, and the anal proleg is about 5 mm.

The pupa is spindle-shaped, 42-45 mm long, grayish brown, with dark brown spots.

Occurrence pattern: this insect has 2-3 generations per year and overwinters as a pupa. In April-May of the following year, it emerges as an adult and begins to activity and cause damage. The adult has phototaxis. Generally, eggs are laid singly on the tender shoots and leaf tips of the host. The second-generation adults appear in July, and the larvae feed on leaves from June to October. After the larvae mature, they spin silk to bind soil and make a cocoon, and pupate in the shallow soil layer.

Chemical control

(1) Plow the soil in winter to eliminate overwintering pupae. During the larval damage period, manual capture and killing can be carried out.

(2) Protect and utilize natural enemies.

(3) Because of its phototaxis, blacklight lamp trapping and killing can be carried out.

(4) Chemical control: during the larval occurrence period, spray 1000x trichlorfon solution or 4000x 2.5% deltamethrin solution.

Commonly used pesticides: trichlorfon, deltamethrin.