Alloxydim (Fig. 1) has been developed by BASF AG for post-emergence control of grass weeds and volunteer cereals in sugar beet, vegetables and broad-leaved crops and it is applied at doses between 0.5 and 1.0 kg a.s./ha. Alloxydim is a selective systemic herbicide from the cyclohexanedione oxime class. This family of compounds has been developed during the last 30 years as post-emergence herbicides that inhibit acetyl-CoA carboxylase [1] and [2], the enzyme that catalyses fatty acid synthesis. The cyclohexanedione ring and the ethoxyimine group linked to ring position 3 seem to be essential for the phytotoxic activity, whereas substitutions in position 6 may vary considerably without large differences on herbicidal activity [1].