Project description

Variety authorisation is a prerequisite for the commercial distribution of seeds of agricultural plant and vegetable species. It helps to ensure the supply of high-quality seed and planting material of healthy, high-quality and high-yielding varieties for agriculture. In order for a new variety to be authorised, it must pass the register test. The register examination uses the so-called DUS test to assess whether a newly bred plant variety differs from existing varieties (distinctness), whether the characteristics are pronounced in all plants of the new variety (uniformity) and whether they are stable within this variety (stability). To this end, new applications are compared with already tested varieties directly in the field and in the laboratory using internationally harmonised test specifications. The focus is on botanical-morphological plant and grain characteristics.

A complete reference collection of currently known varieties is necessary for register testing. The increasing size of these collections is a challenge for test centres in terms of resource planning. The effort required for field trials can be reduced through the targeted selection of the required reference varieties. Since the use of molecular markers for selection is widespread in plant breeding, it makes sense to also use them for variety differentiation in the context of register testing.

In the predecessor project DURDUS, important insights were gained for the utilisation of extensive data sets in register testing. It was tested whether chip technology can be used to differentiate between varieties with the aid of molecular markers in register testing. A commercially available chip was used for this purpose. The analyses were carried out by the chip supplier. The evaluation of the data showed that this approach is suitable for the purpose of variety register testing.

The DURDUStools project utilised these findings in a practice-oriented manner. Analysing and evaluating molecular data requires suitable technical equipment and expertise. These resources are not currently available to all variety testing centres. The use of a chip and the preparation of the data in an easily accessible form closes this gap. The online tool offers users an automated analysis and an easily accessible preparation of the data for direct application.

Results

The aim of the DURDUStools project was to further develop the results obtained in DURDUS and make them usable for variety register testing. To this end, an easily accessible online tool for calculating genetic distance (GD) was developed, which can be used to select reference varieties from the reference collection, together with the botanical-morphological data, for register testing of durum wheat.

The genetic data was generated using a DNA chip (SNP microarray). This method identifies genetic variations that can be used to identify a variety. The DNA profiles of all varieties from the reference collection were then linked to the GD calculation tool. A prototype was developed in the first year of the project and critically tested by the participating test centres. In parallel, the GD threshold for distinctness defined in the DURDUS project was evaluated and refined. In the second year of the project, the examination offices tested the implementation of the final version of the GD calculation tool for the planning of DUS field trials. In the final phase of the project, a draft partnership agreement was defined to ensure the maintenance, access and use of the GD calculation tool beyond the duration of the project.

Benefits of the project

Taking molecular data into account can make it easier for variety testing centres to manage their reference collections and plan trials. The variety testing centres involved have an easy-to-use and useful tool at their disposal.