Common name: bromoxynil

U.S. trade name: BUCTRIL

Bromoxynil [post-emergent (POST)] on redroot pigweed (Amaranthus retroflexus). Note the mottling and numerous necrotic spotting	Bromoxynil (POST) on soybean
Bromoxynil (POST) on common lambsquarters (Chenopodium album)	Bromoxynil (POST) on broadleaf weeds
Bromoxymil (POST) on broadleaf and grass crops and weeds

3,5-dibromo-4-hydroxybenzonitrile.

Nitriles (or Benzonitriles).


6.

Field corn, wheat, oats, barley, rye, triticale, seedling alfalfa, flax, turfgrasses for sod or seed, garlic.

Many annual BLW (broadleaf weeds): wild buckwheat, smartweed, lamb's-quarters, wild mustard kochia, cocklebur, velvetleaf, nightshades (but most effective before 5-leaf stage) Application method: POST.

Absorbed by foliage and moves very little within the plant.

Inhibition of photosynthesis and ATP formation by blocking electron transport.

Inhibition of photosynthesis by binding to the QB-binding niche on the D1 protein of the photosystem II complex in chloroplast thylakoid membranes, thus blocking electron transport from QA to QB;this stops CO2 fixation and production of ATP and NADPH2 which are required for plant growth; however, plant death often results from other factors (e.g. lipid peroxidation).

Differential spray retention, uptake and degradation in tolerant species.

Basically a foliar contact herbicide; causes blistered (mottling) or necrotic spots within 24 hours and extensive destruction of leaf tissue later (4-7 days); chlorosis may appear afterwards around the necrotic areas of leaves; susceptible seedlings become extremely brittle and eventually disintegrate.

Essentially none; short (< 1month).

Oral LD₅₀ = 440 mg/kg - very toxic (BUCTRIL = 779 mg/kg - moderately toxic).

Formulation includes a wetting agent to improve the spread of droplets on leaf; although bromoxynil is not an effective soil-applied herbicide, crops such as turnips, peas and beans should not be seeded for 1-week following application; crop injury (leaf scorch) may develop if plant is under stress (high temperatures or high humidity) within 2 or 3 days before or after application; in corn, problems arise if application followed by a period of cool, wet weather, however, yields are generally not affected.