Fluorouracil, a benzoylurea insecticide, is a chemically stable chemical that is soluble in acetone and dichloromethane. It is a chitin synthesis inhibitor with high insecticidal and ovicidal activity, and is highly effective, especially in controlling cotton bollworms. Mainly used for controlling various insects of Coleoptera, Diptera, and Homoptera in cotton, potatoes, and fruit trees. For example, controlling various pests such as the golden stripe moth, peach leaf miner, leaf roller moth, prickly moth, peach moth, etc. in jujube trees, apples, pears and other fruit trees, and controlling the citrus leaf miner.
Chemical formula: C₁₆H₈Cl₂F₆N₂O₃

Molecular weight: 461.15

CAS login number: 86479-06-3

Melting point (º C): 197-199

Water solubility: soluble in acetone and dichloromethane. Chemical stability.

Density: 1.68 (water=1)

Appearance: White crystals

UN Dangerous Goods Number: UN 3077 9/PG 3

Molecular formula: C16H8Cl2F6N2O3

Toxicity: Low toxicity, acute oral LDso>5000mg/k9 in rats, acute dermal LD50>5000mg in rats

Chemical name: N - [3,5-dichloro-4-one (1,1,2,2-tetrafluoroethoxy) phenyl] -3- (2,6-fluorobenzoyl) urea.

Physical and chemical properties

Colorless solid, melting point 202 ℃~205 ℃. Solubility: Water 0.027mg/L (18 ℃), methanol 11 3g/L (20 ℃), xylene 5.2g/L (20 ℃). 60% hydrolysis occurs within 35 days (pH 9).

Physical and Chemical Properties

【 Melting point (℃) 】: 202~205

【 Vapor pressure (Pa) 】 0.059MPa (25 ℃)

【 Appearance 】Colorless (or white) solid.

【 Solubility 】 Solubility (20 ℃): 0.027 mg/L in water (18 ℃), 11.9 mg/L in methanol, and 5.2 g/L in xylene.

Toxicological data

Acute oral LD50 in mice>5000mg/kg, LD50 in mice>2000mg/kg; Acute transdermal LD50 in rats>2000mg/kg (>5000mg/kg); Acute inhalation LC50>2.5mg/L (4h) in rats. The non effective dose for rats fed for 2 years is 75mg/kg per day, and for dogs fed for 1 year, the non effective dose is 0.5mg/kg per day. Skin sensitization test negative. No teratogenic or mutagenic effects were observed in animal experiments. Rainbow trout LC50>32 × 10-9 (96h). The oral LD50 of bees is 0.1mg/individual; Highly toxic to silkworms and fish.

The problem of drug harm caused by fluorouracil

1. Drug damage causes white spots and whitening spots, which cannot be restored. However, after a period of time (about half a month), the drug damage will become less obvious, mainly manifested in cruciferous vegetables. cruciferous vegetables are already very sensitive, especially during the seedling stage, and the recommended dosage is small.

2. Fluorouracil is relatively safe on cotton and has no problem on rice. The dosage on cotton is controlled at 15 milliliters per bucket of water. Pay attention to the dosage during high temperatures. It is also easy to cause phytotoxicity on cotton, especially in June and July when the temperature is high and the sunlight is strong. Try to use it sparingly or not, and dilute it less than 1000 times (5%). Using it too much on cotton can also cause phytotoxicity, especially when mixed with phoxim.

3. This type of drug damage is mainly determined by the performance of the drug itself, but it is also related to the type of dosage form and dilution ratio. Good dosage form varieties can alleviate the occurrence of drug damage to a certain extent. The medicine is good, but there are too many uncontrollable factors, which may be the main reason why this medicine has not been widely recognized and promoted.

Main purpose and application

Main purpose

It is a new type of acylurea insecticide, which has a wide spectrum of insecticides in addition to other acylurea insecticides. It is particularly effective against pests of the cotton bollworm genus, and has good effects on armyworms such as moths, sky caterpillars, fir moths, sweet armyworms, and valley armyworms. It is ineffective against mites. Strong knockdown ability, faster insecticidal effect than other acylureas, high contact egg killing activity, can be used alone or mixed. The application period is not strictly required, but it can prevent and control pests that have developed resistance to organophosphates and pyrethroids. It is a benzoylurea insect growth regulator that kills pests by inhibiting chitin synthesis in insects. It has the characteristics of high insecticidal activity, wide insecticidal spectrum, strong knockdown power, and quick effect. Its mechanism of action is to inhibit the formation of chitosan, hinder the normal molting and metamorphosis of pests, and also inhibit the feeding speed of pests. It can prevent and control pests of Coleoptera, Diptera, Lepidoptera, and Homoptera on cotton and fruit trees, and has egg killing activity. Especially effective against pests such as cotton bollworms, but ineffective against mites. It is used to control cotton bollworm and pink bollworm. During the peak incubation period, before the larvae enter the buds and bolls, it is spray with 1500~2000 times of 5% emulsifiable concentrates.

Applicable crops

Fluorouracil moths are used to control Lepidoptera pests such as cabbage caterpillars, diamondback moths, beet armyworms, cabbage moths, tobacco bollworms, cotton bollworms, golden striped moths, leaf boring moths, leaf rollers, bridge building moths, E-borers, prickly moths, caterpillars, etc.

Prevention and control targets

Multiple plants such as cotton, tomatoes, peppers, cruciferous vegetables, apples, peaches, and citrus can be used.

Usage

1. To prevent and control various pests of fruit trees such as jujube, apple, pear, etc., such as golden stripe moth, peach latent moth, leaf roller moth, prickly moth, peach moth, etc., 1000-2000 times 5% emulsion can be sprayed during the peak hatching period or young larval stage, and the efficacy can be maintained for more than 20 days.

2. To control citrus leaf miner, 1000 times 5% emulsifiable concentrates can be sprayed spray at the peak of egg hatching.

Precautions

① Insects that feed on leaves should be treated with pesticides during the early larval stage. Dribbling pests should be treated with pesticides during the peak egg laying and hatching periods. This medication has no internal absorption or permeability, and should be sprayed evenly and thoroughly.

② Cannot be mixed with alkaline pesticides. But it can be mixed with other insecticides for better control effects.

③ Be particularly careful as it is highly toxic to fish and silkworms.