Abstract: The invention relates to a process for the incorporation of foreign DNA into chromosomes of dicotyledonous plants by infecting the plants or incubating plant protoplasts with Agrobacterium bacteria, which contain one or more plasmids, wherein bacteria are used which contain at least one plasmid having the vir-region of Ti (tumor inducing) plasmid but no T-region, and at least one other plasmid having a T-region with incorporated therein foreign DNA but no vir-region, as well as to a Agrobacterium bacteria, suitable for use in the process according to claim 1 wherein at least one plasmid which has the vir-region of a Ti (tumor inducing) plasmid but no T-region and at least one other plasmid which has a wild type T-region with incorporated in it foreign DNA but no vir-region.

Abstract: A process for the activation of genes in micro-organisms, in which genes not occurring as such in nature are activated by contact with plants or with the substance or substances causing the activation and present or not in plant fragments or plant exudates, the genes used consisting of one or more proteins encoding fragments of one or more natural genes and/or one or more synthetically produced DNA-sequences, which encode for one or more proteins and a promotor region originating from one of the genes naturally present in micro-organisms and being of such a nature that respectively the effecting or omitting of the above-mentioned contact makes it possible to activate the artificially constructed gene or genes or to stop the activity of the gene or genes, respectively.