Eptam / EPTC
Chemical Name: S-ethyl dipropyl carbamothioate
Chemical Family: Thiocarbamate
EPTC effects
EPTC (PPI) on winter wheat
Note abnormal growth of leaves from coleoptiles
EPTC effects
EPTC (PPI) on grasses
EPTC effects
EPTC (PPI) on soybean
EPTC effects
EPTC (PPI) on broadleaf and grass crops and weeds
WSSA Resistance Group: 8
Crop/non-crop registration: Alfalfa, clover, bird'sfoot trefoil, beans, potatoes, sunflowers
Sensitive weeds: Mostly annual grasses; yellow nutsedge; pigweed, lambsquarters, and nightshade if conditions are favorable for germination/growth.
Application method: PPI - incorporate to 10 cm (4"); should be incorporated shortly after application to avoid volatilization and photodegradation losses, especially on moist soils.
Absorption & Translocation: Readily absorbed by underground plant parts (roots, hypocotyl and seed);upward translocation to growing tips; however, translocation is likely unimportant in herbicidal action because EPTC is absorbed very near its site of action; susceptible weeds are controlled as they germinate; established weeds are not controlled.
Mode of Action: Not well understood.
Metabolic pathway inhibited: May include inhibition of fatty acid and lipid biosynthesis; as well as gibberellin synthesis.
Basis of Selectivity: Metabolized by tolerant species at the seed germination stage by enzymatic breakdown; seed food reserves also allow seedling to outgrow effect.
Symptoms: Inhibits shoot growth of germinating seedlings to a greater degree than roots; induces abnormal growth and emergence of leaves from coleoptiles in grasses; kinking of the first internode into a zigzag pattern is often apparent; leaves of affected plants often appear darker green than tolerant plants; in BLW symptoms are less specific with growth generally inhibited, leaves cupped and having necrotic tissues around edges.
Residuality: Intermediate (1- 4 months); provides season long control with no soil residues in the following year to limit rotations.
Toxicity: Oral LD50 = 1652 mg/kg - moderately toxic (EPTAM = 1325-1500 mg/kg - moderately toxic).
Additional comments: EPTC can be applied PPI in corn, but only with a safener (R25788) packaged in ERADICANE products.