Contraindications of using pyrazosulfuron methyl

Pyrazosulfuron-methyl has a long-lasting effect and can control various weeds during the rice growth period with a one-time application. It has good control effects on broad-leaved weeds, sedge weeds, barnyard grass, etc. Let’s talk about the contraindications of using pyrazosulfuron-methyl.

1. Characteristics of pyrazosulfuron-methyl

1. Unique mechanism of action

Pyrazosulfuron-methyl is a sulfonylurea herbicide that can be used before and after weeds emerge. The agent is mainly absorbed by the young shoots, roots, stems and leaves of weeds and quickly transmitted in the body. By inhibiting acetolactate synthase, it inhibits the biosynthesis of amino acids in the plant, causing the shoots and roots of the weeds to die quickly.

2. Mode of action

Pyrazosulfuron-methyl has excellent systemic conductivity and selectivity.

3. Weed control spectrum

Pyrazosulfuron-methyl has a good control effect on sedge weeds in rice fields, such as sedge, silver rush, water sedge, sedge, and sedge, as well as broad-leaved weeds such as duckweed, pondweed, water horsetooth, wolf grass, Alisma orientalis, Channa intestine , raindrops, water celery, knotweed, and wild arrowhead. It can also control duckweed and is effective against young barnyard grass, but is ineffective against Leptochloa chinensis.

4. Security

The active ingredient of pyrazosulfuron-methyl is rapidly metabolized into harmless inert components after entering the rice body, and is relatively safe for rice.

However, different varieties of rice have significant differences in their resistance to pyrazosulfuron-methyl, and safety tests are required for first-time use.

5. Common compounding

Pyrazosulfuron-methyl can be used to produce complexes with other drugs. Common complexes on the market include: pyrazosulfuron-methyl·pretilachlor, pyrazosulfuron·dimethoprim-methyl, pyrazosulfuron·dichloroquine, pyrazosulfuron·benzothiazide, pyrazosulfuron·butachlor, pyrazosulfuron·pentachlor, pyrazosulfuron·propachlor, pyrazosulfuron·metachlor, pyrazosulfuron·pretilachlor, etc. When choosing a complex, be sure to refer to the instructions for use of the drug.

2. Pyrazosulfuron-methyl usage technology

1. Use period

Pyrazosulfuron-methyl can be used in direct-seeding rice fields and transplanting fields, and can be applied by spraying or soil application.

For direct-seeded rice fields, the pesticide can be applied 5-20 days after direct-seeding the rice, when the weeds are in the 2-5 leaf stage. Before applying the pesticide, drain the field, keep the soil moist, and spray the stems and leaves. 2 days after applying the pesticide, irrigate the fields and maintain a 3-5 cm water layer. The water layer should not submerge the heart leaves of the rice to avoid pesticide damage. Keep water for 5-7 days.

For rice transplanting fields, apply the pesticide 3-8 days after transplanting. Before application, the water depth in the field should be 3-5cm without exposing mud. After application, retain water for 5-7 days. If the water layer is insufficient, water can be added slowly, but the water cannot be drained. The time of application of the medicine should not be too late, after the barnyard grass has 1.5 leaves, otherwise the prevention effect will be affected.

Cannot be used during late rice sprout stage.

2. When to use

When using pyrazosulfuron-methyl, avoid high temperature periods. When the temperature is high, transplanting should be done before 9 am or after 4 pm. It is not advisable to apply pesticides in the morning when the dew on the rice leaves has not dried yet.

3. Dosage

The drug has high activity and low dosage, and the dosage should be applied accurately.

Do not overdose during use and apply the medicine evenly and carefully.

4. Sensitive crops

Pyrazosulfuron-methyl is quite sensitive to Umbelliferae crops such as carrots , celery, and coriander, so be careful to avoid them when applying the pesticide. Do not drain water from the fields where pesticides are applied into straw fields, lotus fields, water chestnut fields, etc. to avoid pesticide damage.

5. Interval period after next crop

After using this product, there should be a minimum interval of 80 days before planting the next crop.

3. Contraindications of using pyrazosulfuron-methyl

1. Pyrazosulfuron-methyl should not be mixed with copper preparations or alkaline agents, otherwise the efficacy will be reduced!

2. It is prohibited to use near aquaculture areas, rivers, ponds and other water bodies. It is prohibited to raise fish, shrimp and crabs in rice fields, and the pesticide solution must not be discharged into the water. It is prohibited to clean pesticide application equipment in water bodies such as rivers and ponds.

3. Pay attention to alternating medications.

4. When preparing medicine, be sure to use the double dilution method and prepare it before use. The prepared medicine cannot be kept overnight.

5. If you have no experience in use, be sure to conduct a safety test first.

6. Pyrazosulfuron-methyl is irritating to the eyes, skin and mucous membranes, so take precautions when using the medication.

That’s it