Carfentrazone-ethyl 10% WP – Advanced Protoporphyrinogen Oxidase (PPO) Inhibitor Herbicide

Carfentrazone-ethyl 10% WP: A fast-acting, low-toxicity wettable powder herbicide targeting broadleaf weeds in cereals, rice, and corn. Known commercially as (Kuaimieling), it delivers rapid desiccation of resistant weeds within hours and is globally registered for integrated weed management systems

Technical Specifications

Parameter	Specification
Active Ingredient	Carfentrazone-ethyl 10% (w/w)
Chemical Class	PPO inhibitor (IRAC Group 14)
Formulation	Wettable Powder (WP)
Molecular Formula	C₁₅H₁₄Cl₂F₃N₃O₃
Toxicity	Low mammalian toxicity (Rat acute oral LD₅₀: >5,000 mg/kg; WHO Class U)
Target Weeds	Stellaria media (chickweed), Amaranthus retroflexus (pigweed), Portulaca oleracea (purslane), Galium aparine (cleavers)
Rainfastness	1 hour
Shelf Life	2 years (stored at 10–30°C in dry conditions)

Mode of Action & Key Features

Mechanism: Inhibits protoporphyrinogen oxidase (PPO), causing cellular membrane disruption and rapid desiccation
Speed: Visible weed wilting within 1–4 hours; complete kill in 24–48 hours
Resistance Management: Highly effective against sulfonylurea-resistant weeds (e.g., Capsella bursa-pastoris)
Crop Safety: Safe for wheat, corn, rice, and barley; no phytotoxicity at recommended doses

Application Guidelines

Registered Crops & Dosage:

Crop	Target Weeds	Dosage (g/ha)	Timing	PHI (Days)
Winter Wheat	Chickweed, pigweed	27–30	Post-emergence (weeds 2–4 leaf)	21
Corn	Purslane, nightshade	24–30	3–5 leaf stage	45
Rice (Paddy)	Broadleaf weeds	30–54	Early tillering	66

Field Efficacy Data (Winter Wheat, Shanxi, China):

15 DAT: >70% control of Descurainia sophia and Capsella bursa-pastoris
30 DAT: Near 100% efficacy; yield increase of 3.9–9.1%

Safety & Environmental Profile

Ecotoxicity:
- Fish: LC₅₀ (96h) = 1.6–4.3 mg/L (moderately toxic)
- Bees: Low risk (LD₅₀ >100 μg/bee)
Precautions:
⚠️ Buffer Zones: 50m from aquatic habitats
⚠️ Re-entry Interval: 24 hours.
⚠️ Avoid application during cereal flowering to protect pollinators.

Global Regulatory Status

Region	MRLs (ppm)	Key Crops
Canada	0.10 (tree nuts) 8	Barley, oats, wheat
USA	2.0–15.0 (animal feed) 9	Non-grass animal feed (Group 18 crops)
Brazil	0.1 (cotton); 0.05 (corn) 7	Soybean, sugarcane, coffee

Advantages & Limitations

Advantages:
✅ Rapid symptomology: Visible weed necrosis within hours
✅ Low use rate: 24–54 g/ha minimizes environmental load
✅ Rainfast after 1 hour: No re-spray needed if rain occurs post-window

Limitations:
⚠️ Ineffective on grasses: Combine with grass-specific herbicides (e.g., fenoxaprop)
⚠️ Reduced efficacy in low light: Avoid cloudy days