he breeding of new varieties is more and more a matter of the use of molecular based breed- ing techniques. The classical crossing and selecting of plants, moved to marker assisted breeding, is where the crosses are checked on a molecular level to see if the desired traits are present in the cross. Today, even marker driven breeding techniques are used, where on a molecular level, ‘varieties’ are cre- ated and only at the end of the process, a grow-out is organised for a final check and selection. In the meantime the process to grant plant variety rights is still based on the same principles that applied when the International Union for the Protection of New Varieties of Plants (UPOV) was created in 1961; the morphological description of a set of pre-defined char- acteristics, and a new variety needs to be Distinct, Uniform and Stable (DUS) Logically the question is if there is room for the use of molecular techniques in this DUS process? To answer this question, we have to look at the ’91 UPOV convention that says in art 7: Distinctness: “The variety shall be deemed to be distinct if it is clearly distinguishable from any other variety whose existence is a matter of common knowledge at the time of the filing of the application. ……” In this article, no mention is made of the techniques that are to be used to establish if a candidate variety is distin- guishable from any variety of common knowledge. To study that, we have to look at the definition of variety in art 1 of the said convention: “Variety” means a plant grouping within a single botanical taxon of the lowest known rank, which grouping, irrespective of whether the conditions for the grant of a breeder's right are fully met, can be: • defined by the expression of the characteristics resulting from a given genotype or combination of genotypes, • distinguished from any other plant grouping by the expression of at least one of the said charac- teristics and • considered as a unit with regard to its suitability for being propa- gated unchanged. This combination of articles is clear; the method to test if a variety can be granted plant breeders rights (PBR) is based on the expression of the charac- teristics that result from a certain genetic composition. EXISTING POSSIBILITIES Despite this basic statement, there is a general feeling that molecular techniques are useful and may even be required to keep the quality of the DUS decision high, and at the same time, help to keep the costs of a DUS test reasonable. Therefore, UPOV has already estab- lished principles to guide the use of molecular techniques. It is possible to apply a molecular test to replace a bio test. This can be useful in a case where, A LOOK AT THE UPCOMING PARADIGM SHIFT OF HOW WE DISTINGUISH PLANT VARIETIES. BY: KEES VAN ETTEKOVEN T IS THERE ROOM FOR BIO MOLECULAR TECHNIQUES IN THE DUS PROCESS? 10 I EUROPEAN SEED I EUROPEAN-SEED.COM DNA profiles are not sensitive to external environmental factors and are considered as an objective description of the genotype.