In Europe, new seed varietes need to be approved by a national seed register, before they are sold on th market. This is independent on whether they are GM or not. It is tested whether the varieties are stable, whether they can be distinguished clearly from other varieties and whether they perform better then other varieties.
The national seed catalogues were introduced when seed producers started to produce seed commercially on a larger scale, to ensure that farmers would know what they are buying. In a system where seed is farm-saved or where small quantities of seeds are swapped between farmers that know one another such a controll system is generally not needed.
Landraces often do not fulfill the criteria of unique, stable and distinguishable, because their strenght is often that they contain different types, and that their performance meets the spefic area in which they are grown without necessarily outperforming other varieties under a number of different growing conditions.
New varieties in a seed approval procedure are supposed to be grown without agrochemicals to evaluate their strength. Herbicide resistant crops however are meant to be grown with herbicide application, and often they will only have a chance to outperform conventional varieties if herbicides are applied. It is unclear how the different competent authorities in the European Union are about to handle this.