Common name quinclorac (BSI, E-ISO, (m) F-ISO)    

IUPAC name 3,7-dichloroquinoline-8-carboxylic acid    

Chemical Abstracts name 3,7-dichloro-8-quinolinecarboxylic acid 

CAS RN [84087–01–4] EC no 402–780–1   

PHYSICAL CHEMISTRY    

Mol. wt. 242.1 M.f. C₁₀H₅Cl₂NO₂ Form White/yellow, practically odourless solid. M.p. 274 °C V.p. <0.01 mPa (20 °C) Kow logP = –0.74 (pH 7) S.g./density 1.68 Solubility In water 0.065 mg/kg (pH 7, 20 °C). In acetone <1 g/100 ml (20 °C). Practically insoluble in other organic solvents. Stability Stable for 24 months at 50 °C. pKa 4.34 (20 °C)     

APPLICATIONS    

Biochemistry Synthetic auxin (acting like indolylacetic acid); also inhibitor of cell wall (cellulose) biosynthesis. 

Mode of action Rapidly absorbed through the foliage. Weak auxin activity as determined in wheat coleoptile elongation test, cucumber root elongation test, cucumber curvature test and ethylene biosynthesis test in soya beans. No influence on Hill reaction. Plant response is similar to IAA or auxin-type herbicides of the class of benzoic acids and pyridine compounds.    

Uses Pre- and post-emergence control of grass weeds (Echinochloa spp., Aeschynomene spp., Sesbania spp.) and other weeds in direct-seeded and transplanted rice, at 0.25–0.75 kg/ha. Phytotoxicity Non-phytotoxic to transplanted and direct-seeded rice. Under continuous irrigation conditions, injury may occur in adjacent umbelliferous crops if connected to the same waterway.    

Formulation types SC; WG; WP. 

Compatibility Good combination partner for all rice herbicides which are insufficiently effective against Echinochloa.