Methionine biosynthesis inhibitor. Prepn: A. Hubele, EP 310550; idem, US 5153200 (1989, 1992 both to Ciba-Geigy). Comprehensive description: U. J. Heye et al., Crop Prot. 13, 541-549 (1994). Mechanism of action: P. Masner et al., Pestic. Sci. 42, 163 (1994). Review of field trials: N. J. Leadbitter et al., Br. Crop Prot. Counc. Monogr. 57, 73-78 (1994).