Abstract: The invention provides for a system for uploading genes of interest into an artificial chromosome expression system (ACE) that has been engineered to include multiple sites for site-specific, recombination directed integration, whereby a second or further gene of interest can be loaded onto the ACE by a targeting vector, through the acceptor recombination site(s) on said ACE.

Abstract: The invention relates to a herbicidal composition which contains, besides binding, wetting, dispersing, emulsifying agents, solvents and/or surface-active substances, herbicides as active agent of thiocarbamate, carbamate, acid amide or urea type alone or in a combination, furthermore as antidote a compound of the general formula I ##STR1## wherein R.sup.1 and R.sup.2, independently of each other, are hydrogen, C.sub.1-6 alkyl, C.sub.2-6 alkenyl, C.sub.1-4 cyanoalkyl, C.sub.1-6 haloalkyl, phenyl-C.sub.1-4 -haloalkyl, phenyl, halogenphenyl, C.sub.1-4 -alkyl-phenyl, C.sub.1-4 -alkoxyphenyl, furfuryl;R.sup.3 and R.sup.4, independently of each other, are hydrogen, C.sub.1-18 -alkyl, C.sub.2-4 -haloalkyl, C.sub.2-4 -cyanoalkyl, C.sub.1-4 -alkoxy-C.sub.2-4 -alkyl, C.sub.5-6 -cycloalkyl, phenyl-C.sub.1-4 -alkyl, C.sub.3-4 -alkenyl, phenyl-C.sub.3-4 -alkenyl, di-C.sub.1-4 -alkylamino-C.sub.2-4 -alkyl, hydroxy-C.sub.2-6 -alkyl, furfuryl, tetrahydrofurfuryl, C.sub.1-4 -alkoxy-C.sub.2-4 -alkoxy-C.sub.2-4 -alkyl;R.sup.