Tribenuron methyl

It is white solid. m.p. 141℃ , vapor pressure 0.036×10-3Pa(25℃ ). The solubility in water is 28mg/L, 50mg/L and 280mg/L at pH4, pH5 and pH6 respectively; the solubility in organic solvents are: acetone 43.8mg/L, acetonitrile 54.2mg/L, carbon tetrachloride 3.12mg/L, ethyl acetate 17.5mg/L, hexane 0.028mg/L. The distribution coefficient (n-octanol/water ) 0.36 (pH=7). Stable in storage at room temperature, stable to light, hydrolyzed at 45° C, stable at pH 8-10, but rapidly hydrolyzed at pH <7 or >12. Half-life in soil 1 to 7d.

As a herbicide in wheat field, it can eff ectively control the annual broad-leaved weeds such as Zoysia japonica, shepherd's purse, wheat bottle grass, calamus, shepherd's purse, quinoa, amaranth, etc

Tribenuron Methyl is a selective, systemic herbicide belonging to the sulfonylurea class. It is widely used for post-emergent control of broadleaf weeds in cereal crops. Known for its low application rates and high efficacy, tribenuron methyl is a preferred choice in modern agricultural practices.

Key Features

1. Selective Action: Targets broadleaf weeds without affecting cereal crops.

2. Systemic Herbicide: Absorbed through foliage and roots, translocating throughout the plant.

3. Low Dose Requirement: Effective at very low application rates, reducing environmental load.

4. Crop Compatibility: Safe for wheat, barley, and other cereal crops when used as directed.

Applications

Crops Treated

• Wheat

• Barley

• Oats

• Rye

Weeds Controlled

• Wild Mustard (Sinapis arvensis)

• Shepherd's Purse (Capsella bursa-pastoris)

• Chickweed (Stellaria media)

• Pigweed (Amaranthus spp.)

• Thistle (Cirsium spp.)

Mechanism of Action

Tribenuron methyl inhibits the enzyme acetolactate synthase (ALS), which is essential for the synthesis of branched-chain amino acids. This disruption halts protein synthesis, leading to stunted growth and eventual death of the weed.

Advantages

1. Effective on Young Weeds: Best results are achieved when weeds are actively growing.

2. Low Residual Activity: Minimal carryover effects, allowing flexibility in crop rotation.

3. User-Friendly: Easy to apply with conventional spray equipment.

4. Resistance Management: Can be rotated with herbicides of different modes of action.

Safety and Environmental Considerations

Handling and Storage

• Use appropriate personal protective equipment (PPE) during handling and application.

• Store in a dry, well-ventilated area away from food and water sources.

Environmental Impact

• Low Toxicity: Minimal impact on non-target organisms when used as directed.

• Soil Binding: Binds to soil particles, reducing leaching potential.

• Aquatic Safety: Avoid application near water bodies to prevent contamination.

Regulatory Compliance

• Adhere to local regulations and label instructions for safe and effective use.

Limitations

• Limited Weed Spectrum: Primarily effective against broadleaf weeds; not effective on grasses.

• Resistance Development: Overuse may lead to the development of resistant weed populations.

• Application Timing: Requires precise timing for optimal efficacy.

Conclusion

Tribenuron methyl is a highly effective herbicide for controlling broadleaf weeds in cereal crops. Its systemic action, low application rates, and compatibility with integrated weed management programs make it a valuable tool for farmers. To ensure sustainable use, it is essential to follow recommended application practices and rotate with herbicides of different action modes.