What does the field pest armyworm look like? What is the best medicine to use? What are the prevention and control techniques?

Armyworm is a kind of insect, also known as millet night larvae, shaving insects. Commonly known as colorful insects, wheat silkworms, etc., the hosts are cereal crops such as wheat, rice, millet, corn and more than 104 species of plants belonging to 16 families, such as cotton, beans and vegetables. What does the armyworm look like? What is the best medicine to use? What are the prevention and control techniques?

What does the armyworm look like?

1. Eggs: about 0.5mm, hemispherical, white, gradually yellow, shiny. The eggs are arranged in a single layer in rows and clumps.

Larvae: the body length of mature larvae is 38mm. The head is reddish brown, the head cover is reticulated, the forehead is flat, there are thick brown longitudinal lines on both sides, slightly eight-shaped, and brown reticulate on the outside. The body color varies greatly from light green to thick black (often due to different food and environment); in large occurrence, the back is often black, the ventral side is light dirty, the back midline is white, and there is a slight bluish between the subback line and the upper valve line. Pink to grayish white between the valve line and the lower valve line. There is a wide black-brown longitudinal band on the outside of the ventral foot and a half-ring black-brown toe hook at the apex of the foot.

2. Pupae: about 19mm, reddish brown, with a row of dentate punctures on the dorsal front of the abdominal 5-7 segments, 4 spines on the gluteal spine, 2 thick in the center, and slightly curved thin short spines on both sides.

3. Adult: body length 15~17mm, wingspan 36~40mm. The head and chest are grayish brown and the abdomen is dark brown. The front wing is grayish brown, yellow or orange, which varies a lot; the inner horizontal line often shows only a few black spots, the ring and the kidney grain brown yellow, the boundary is not significant, there is a white dot at the back end of the kidney grain, and there is a black spot on each side of the kidney grain; the outer horizontal line is a row of black spots; the submarginal line is a row of black spots from the top angle to the marginal line of Mz;. The hind wings are dark brown and gradually fade to the base.

What is the best medicine for armyworm? What are the prevention and control techniques?

1. Control the larvae, reduce the harm and reduce the base. According to the principle of "focusing on the young instar with contact insecticides and protecting the elder instar with stomach poison agents", the larvae were sprayed in time at the initial stage of the occurrence of the second generation larvae, and the larvae were eliminated before the third instar as far as possible.

(1) reach the standard of prevention and control. When the population density of rice field is 150.20 heads per square meter and that of corn field is more than 10 heads per 100 plants, 50% phoxim EC, 80% dichlorvos EC, 40% chlorpyrifos EC, 75g 100g water 50kg or 20% cypermethrin 20ml 30ml or 4.5% cypermethrin 50ml plus water 30kg uniform spray per mu can be used. Or spray control with 5% fenpropathrin EC, 5% fenvalerate EC, 2.5% cyhalothrin EC, 2.5% deltamethrin EC 1000 times 1500 times, 40% omethoate 1500 times, 10% imidacloprid 2000 times.

(2) early prevention and treatment. The larvae of young larvae can be sprayed with 4000-fold solution of 5% carbazuron EC, urea-1, urea-2 or urea-3, which is effective in controlling armyworm larvae and does not kill natural enemies.

2. Scientific operation and safe use of drugs. The spraying time should be before 9: 00 a.m. or after 5: 00 p.m., if it is rainy, it should be sprayed in time, the spray should be uniform and thoughtful, the field should be sprayed, and the weeds on the roadside should be sprayed. When the age of the insect is older, the dosage should be increased appropriately. For fields with a large number of insects, you can first beat the plant to shake the armyworm off the ground, and then spray to the ground, which can achieve good results. The spraying machine can use self-propelled tall stalk crop sprayer, air-fed sprayer or smoke sprayer. Wear protective clothing and mask when spraying.

3. Build a blockade to prevent transfer. When the armyworm larvae are harmed by migration, they can dig deep ditches on the road where they are transferred, concentrate on the armyworm falling into the ditch to prevent its continued migration, or spread a 15 cm wide medicine belt to block it, or sprinkle phoxim poisonous soil in wheat or corn fields to establish an isolation zone.

4. Control adults and reduce oviposition. Based on the oviposition habit, phototaxis and chemotaxis of armyworm adults, cereal straw handle, sugar and vinegar solution, sex trap and insecticidal lamp were used to reduce the number of eggs laid by the second generation adults and the population density in the field. reduce the occurrence base and control pressure of the third generation armyworm.

(1) the method of grain and straw handle. Generally tie the grass handle with a diameter of 5 cm, insert 60 to 100 per mu, change the grass handle once every 5 days, and burn the withered grass to destroy the armyworm eggs.

(2) Sugar and vinegar method. Take 350 grams of brown sugar, 150 grams of wine, 500 grams of vinegar, 250 grams of water, and 15 grams of 90% crystal trichlorfon to make sweet and sour lure, which is placed at a height of 1 meter in the field to trap and kill adults of armyworm.

(3) sexual inducement. With a dry trap equipped with armyworm sex trap, one plug per mu was hung in the corn field to trap and kill spawning adults.

(4) Insecticidal lamp method. During the adult mating and spawning period, insecticidal lamps were placed in the field with a distance of 100 meters, and the lights were turned on from 8: 00 p.m. to 5: 00 a.m., to trap and kill adults.