Metribuzin

Metribuzin is a low-cost non-selective herbicide belonging to the chemical class of triazinones. Metribuzin inhibits plant DNA synthesis and acts on photosystem II, ultimately suppressing photosynthesis. Metribuzin provides excellent control of important annual grass and broadleaf weeds^[1][2]. In Vitro:Metribuzin inhibits photosystem II electron transport in plant chloroplasts, exerting herbicidal effects^[2]. In Vivo:Metribuzin (105-175 g a.i ha^-1 + Ad-500 400 mL ha^-1; 105-175 g a.i ha^-1 + Bio-power 400 mL ha^-1; foliar spray; single application at two- to four-leaf weed stage) 175 g a.i ha^-1 + Bio-power 400 mL ha^-1 provides the most effective control of associated wheat weeds and maximizes wheat grain yield (3.91 kg ha^-1), while metribuzin combinations with adjuvants improve efficacy over metribuzin alone at all tested doses^[1].
Metribuzin (6.44 mg/kg) disrupts glomerular function in pregnant rabbits^[2].
Metribuzin (single dose; p.o.) has an acute oral LD₅₀ of 1090 mg/kg in rats^[2].