Control Methods of Common Pests on Flowers and Plants--Silkworm Moth

The silkworm moth Philosamia cynthia Walker et Felder belongs to the family Lepidoptera. The main hosts are walnut, pomegranate, citrus, castor, pepper, Toona sinensis, tallow, ginkgo, Ma Gui Mu, Camptotheca acuminata, white orchid, Robinia pseudoacacia, willow and so on.

Damage characteristics

Larvae feed on leaves and buds, light ones eat leaves into notches or holes, and when serious, eat up the leaves.

Morphological characteristics

The adult has a body length of 25-30mm and a wingspan of 110-130mm. The body is bluish brown. All around the head, the front of the neck plate, the posterior edge of the forechest, the back of the abdomen, the lateral line and the end are all white. There are 6 pairs of white markings on the back of the abdomen, among which there are intermittent white vertical lines. The forewing is brown, the trailing edge of the apical horn of the forewing is obtusely hooked, the apical angle is round and prominent, pink-purple, with black eye-shaped spots, the upper edge of the spot is white arc. There is a large crescent-shaped spot in the center of the front and rear wing, the upper edge of the crescent-shaped spot is dark brown, the middle is translucent, and the lower edge is yellow; the outside has a wide band that runs through the whole wing, which is pink in the middle, white on the outside, dark brown on the inside and brown at the base angle. there's a white twist on the edge. Egg grayish white or yellowish white, with a few dark spots, flat oval, about 1.5mm. The larvae are yellowish and have black spots. After middle age, all are covered with white powder and turquoise. The body length of mature larvae is 55-75mm. The body is thick, the head, forechest, middle chest symmetrical blue-green spinous process, this process tilts slightly backward. The one on the topline is larger than the other two rows, with black dots between the protuberances. The valve screen is yellowish and the surrounding valve is black. The chest foot is yellow, the abdominal foot is turquoise, and the end is yellow. The cocoon is pocket-shaped or olive-shaped, about 50mm, with an opening at the upper end, small at both ends and thick in the middle, decorated with silk leaves, yellowish or grayish white. The stalk of the cocoon is about 40-130mm long, and half of the cocoon is often wrapped in a host leaf. The pupa is brown, 26-30mm long and 14mm wide. Oval, with many horizontal wrinkles on the body.

Occurrence regularity

There are 1-2 generations in the north and 3 generations in the south, overwintering as pupae. The overwintering pupae in Sichuan began to emerge into adults in late April. The adults have phototaxis and have the ability to fly over a long distance, which can reach more than 3000m. Eclosion adults mate immediately. The sexual attraction of the female moth is very strong, the unmated female moth is placed in the indoor cage to attract the male moth continuously, the female moth can promote mating after cutting off its wings, but the moth raised in the room is not easy to mate. The life span of adults is 5ml for 10 days. Eggs are laid on the back and surface of the host leaves, accumulating in piles or lumps, about 300 eggs per female, and the egg duration is 10 mi 15 days. The newly hatched larvae had the habit of clustering, and the damage was gradually dispersed after the 4th instar. From the bottom to the top of the branches and leaves, they feed day and night and can be migrated. The first generation larvae were damaged in May, and the larval duration was about 30 days. After molting, the larvae often eat up or leave only a little of the molted skin. When the larvae mature, they will cocoon the leaves on the tree. when there are no leaves on the tree, the lower tree will pupate with brown cocoons on the ground cover. The cocoon period of the second generation is about 50 days, and the Eclosion and spawning time of the first generation adults is at the end of July and the beginning of August. The second generation larvae are harmful from September to November, and then the second generation overwintering cocoons are produced one after another. The second generation overwintering cocoons last for 6 months, and the pupae are hidden in thick cocoons. The overwintering generation often forms cocoons on the twigs of dense shrubs such as citrus and pomegranate, and on a pomegranate or citrus tree, 30-40 overwintering cocoons are often found in serious cases.

Prevention and cure method

(1) manual capture. After adults lay eggs or larvae form cocoons, they can be removed by manpower or killed directly. The cocoons can be used for nest silk and oil extraction.

(2) Light trapping. Adults have phototaxis, and a good control effect can be obtained by mastering the emergence period of each generation of adults and trapping them with black light at the right time.

(3) Pesticide control. At the initial stage of larval damage, 90% trichlorfon is sprayed with 1500ml 2000 times liquid; 20% dichlorvos heavy fuming agent can also be used, per 667m20.5-0.7kg, the effect of controlling young larvae is very good. Pyrethrum or ivy essence can also be used for prevention and control.

(4) Biological control. It has been found that the natural enemies of Bombyx mori larvae are cocoon wasp, Himalayan tumor wasp, rice hydatid black tumor wasp, Bombyx mori black spot tumor wasp and so on. These natural enemies should be well protected and utilized.

Control methods of silkworm moth, a pest of landscaping

Philosamia cynthia Walker et Felder belongs to Lepidoptera, Bombyx mori family. It is distributed in many areas. The larvae are harmful to Toona sinensis, Sapium sebiferum, holly, paulownia, Magnolia, Michelia, Robinia pseudoacacia, camphor, salt, cherry, cherry, pear, hibiscus, ginkgo and willow.

The adult is about 28 mm long, the wingspan is about 128 mm, and the body is bluish brown. The front wing is yellowish brown, the top angle is round and prominent, there is a >-shaped white band at the base, there are crescent-shaped white lines in the center, the exterior lines are all white, there are tan fine edges, and the wing surface has pink-purple markings. The egg is oblate-oval, gray-white, with brown spots. The mature larvae are about 70 mm long, thick and turquoise. The insect body is covered with white powder, each body segment has 6 spines, and there are dark brown spots between the protuberances. Pupa brown, lotus seed-shaped. Cocoon silk, olive-shaped, the upper end of the hole, cocoon handle long, often with 1 leaf wrapped half of the cocoon.

[comprehensive management]

The main results are as follows: (1) to protect and utilize natural enemies such as cocoon wasp and silkworm black-spot wasp.

(2) trapping and killing adults by using black light or sex attractants.

(3) when the chemical control is serious, spray 1500fold solution of high efficiency Bt powder or 600fold solution of Bacillus borer killer powder.

Control methods of silkworm moth in ornamental trees

Philosamia Cynthia Walker et Felder is also known as Sapium sebiferum. It belongs to Lepidoptera, Bombyx mori family. It is widely distributed in China. The larvae are harmful to Toona sinensis, Sapium sebiferum, Magnolia mandshurica, citrus, holly, paulownia, Magnolia, Michelia, Robinia pseudoacacia, camphor, salt wood, cherry, cherry, hibiscus and ginkgo.

The adult body is about 30 mm long, the wingspan is about 128 mm, and the body is bluish brown. The forewings are yellowish brown, the top corners are round and protruding, and there is a black spot. There is a ">"-shaped white belt at the base, crescent-shaped white lines in the center, white exterior lines, brown fine edges, and pink-purple markings on the wing surface. The egg is oblate-oval, gray-white, with brown spots. When mature, the larvae are about 70 mm long, thick and turquoise. The insect body is covered with white powder, each body segment has 6 spines, and there are dark brown spots between the protuberances. The pupa is brown. Cocoon silk, olive-shaped, the upper end of the hole, cocoon handle long, often with 1 leaf wrapped half of the cocoon.

Integrated prevention and cure

The main results are as follows: (1) to protect and utilize natural enemies such as cocoon wasp and silkworm black-spot wasp.

(2) trapping and killing adults by using black light or silkworm moth sex attractant.

(3) when the biological control is serious, spray 1500-fold solution of high-efficiency Bt powder or Bacillus borer-killing powder.