Who is the great god, please tell me what bug is in the middle? Which part of the plant is harmful? How to prevent it?

Dendrolimus punctatus is the general name of the genus Dendrolimus in Lepidoptera. Also known as caterpillar and fire caterpillar, it was called pine silkworm in ancient times. Harm Pinaceae and Cupressaceae. The earliest record of China can be found in 1530 in Longchuan County, Guangdong Province: "In the ninth year of Jiajing in the Ming Dynasty, there was a severe drought year after year, and the pine leaves were dried up, making cocoons and pine branches, and it was completely melted at the end of winter." Up to now, Dendrolimus punctatus is still the main forest pest with large occurrence and wide harm.

Biological control measures

1, Beauveria bassiana control

Beauveria bassiana can be used in all types of areas. Beauveria bassiana can be used to control Dendrolimus punctatus in the middle and late winter generation (1 1) or February-April of the following year, but Beauveria bassiana is generally not suitable for other generations (or time). The amount of bacteria applied is per mu 1.5-5.0 trillion spores. The application of Beauveria bassiana to control Dendrolimus punctatus or Dendrolimus punctatus in northern China requires 24? In rainy days or dew conditions above C, the amount of bacteria applied should be increased by 3-4 times.

Usage: use plane or ground powder spraying, low-volume spraying and ultra-low-volume spraying; Ground manual powder gun. Preventive measures can also be taken by manually tapping the powder bag to release live insects with bacteria.

2. Control of Bacillus thuringiensis

Bacillus thuringiensis is used to control Dendrolimus punctatus, generally controlling 3~4 instar larvae. The suitable temperature for stent application is 20~32? C. The amount of bacteria applied per mu is 400,000-800,000 international units (IU). Use with caution in rainy season.

Usage: powder spraying, ground routine or small amount spraying, and aircraft small amount spraying. A certain dose of washing powder or other synergist can be added to the spray.

3. Control cytoplasmic polyhedrosis virus (CPV)

Collecting dead insects, extracting polyhedrosis virus, collecting insects through fences or cages, collecting eggs and proliferating viruses, artificially raising proliferating viruses, proliferating viruses in vitro, or infecting and proliferating high insect population in forests, etc., and making into oil emulsion, virus liquid or powder. When used, 0.06% copper sulfate or 0. 1 100 million spores /ml Beauveria bassiana can be added to the virus solution as an inducer to improve the insecticidal rate. The dosage per mu is 5-20 billion virus crystals.

Usage: low-volume spraying, ultra-low-volume spraying or powder spraying on aircraft or ground.

Step 4 attract beneficial birds

Artificial nests can be set up in old forests with low insect population density to attract beneficial birds. The nesting time, number and nest box type depend on the birds attracted.

Step 5 release Trichogramma

At the early stage of laying eggs, Dendrolimus punctatus released good bee species in the forest by stages in sunny and windless weather, with 365,438+10,000 bees per mu. It can also make Trichogramma carry virus at the same time, and improve the control effect. [ 1]

Physical prevention and control

The population density of the next generation of Dendrolimus punctatus can be reduced by manually removing egg pieces or luring integrated worms with black light.

Prevention and control in botanical insecticide

Using 1.2% tobacco alkaloid to control larvae, the ratio of tobacco alkaloid to diesel oil is 1: 20, and the dosage per mu is 0.4 liter.

Bionic chemical control

When necessary, use clofenuron (30g/mu) and clofenuron (5g/mu).

pine caterpillar

Carry out low-volume and ultra-low-volume spraying by aircraft and low-volume and ultra-low-volume spraying by ground backpacks, focusing on the prevention and control of larvae. The ground dosage is 50%- 100% higher than that of aircraft spraying. In the forest land where pine trees are seriously damaged and have weak growth potential, clofenurea and a small amount of urea (about 50 grams per mu) can be sprayed together.

Chemical control

In principle, chemical pesticide spraying, powder spraying and smoke spraying are not used for the control of Dendrolimus punctatus. If necessary, then

Prevention and treatment

Insecticides should be selected to prevent and control small areas of insect sources in the early stage of the outbreak and reduce the insect population quickly. In northern China, Dendrolimus punctatus overwintering under a tree can kill overwintering and overwintering larvae by using poison pens, poison papers and poison ropes made of pyrethroids coated on the trunk before climbing the tree in spring and autumn.

Natural prevention and control law

Although the population density is high and the damage rate of pine leaves is above 70%, the parasitism rate of Dendrolimus punctatus is high, and no drug control is carried out when the insect situation shows a downward trend. When Dendrolimus punctatus occurs in a safe area and in a small area in an occasional disaster area, it is allowed to rise and fall naturally without drug control.