09.08.2013

Foreign DNA in organic vegetables – ifp offers CMS hybrid detection

Surveys commissioned by a TV magazine found foreign genetic material in 17 out of 37 vegetable samples that had been bought from various organic food shops. The samples in question are hybrid species that were grown by means of the CMS method (cytoplasmatic male sterility).

Contrary to some first interpretations of the report, these are not genetically modified organisms (GMO) that are subject to special approval or special labelling regulations. The use of CMS hybrid technology is permitted both for conventional crops and according to the regulations of the European organic label (EU Eco-regulation No. 834/2007).  German organic associations, such as Demeter and Bioland, however, whose own regulations go beyond European legislation, strictly reject the use of CMS technology.

The CMS method is performed in labs in order to modify plants. It is applied mainly to vegetable species. (Grains are usually modified with other methods). The CMS method introduces the cytoplasm of closely related species, whose male plants are naturally sterile, into the plant by means of cell fusion. The mitochondrial DNA introduced in this way transfers the male sterility to the hybrid plant. This raises the plants’ yield, since self-pollination is now ruled out. The desired effect, however, only shows in the first filial generation (F1). With further reproduction being impossible, seeds for cultivation must be purchased anew each time. Sterile seeds are hence mainly used with annual plants.

ifp offers real-time PCR detection for the mitochondrial DNA of Japanese radish (in cabbage species) and sunflower (in chicory). Since the CMS method only works with closely related species, radish or sunflower cytoplasm cannot be used for all plants, i.e. the currently available tests cannot be applied universally for the detection of CMS technology in all vegetable species. Yet if the species, whose cytoplasm was introduced, is known, detection can be established.