The present invention relates to a method of applying a Chemical Hybridization Agent (CHA) to a plant comprising the steps of (a) Providing a source comprising at least one CHA； (b) Bringing said source in contact with at least one root of a plant and (c) Having the at least one root take up at least a part of said at least one CHA. The invention furthermore relates to methods of producing a haploid and/or doubled-haploid plant or hybrid seed. The present invention may be used in various aspects of plant breeding.
