Swiss research institute Agroscope has been granted approval by the Federal Office for the Environment to use new genetic breeding techniques in a field trial with Golden Promise spring barley.

The new trail will look at a barley gene which has been disabled by new breeding techniques. The trial, which will be launched in spring 2024 on a protected site in the Zurich-Reckenholz region, will run for three years, it has been confirmed.The specific gene being looked at is called CKX2 and is involved in the regulation of seed formation.

Disabling this gene by means of a new breeding method called CRISPR/Cas9 has already brought about increased yields in rice and oilseed rape.

The project builds on research from Freie Universität Berlin where it was observed that barley possesses two slightly different copies of this CKX2 gene. In partnership with scientists from the Leibniz Institute of Plant Genetics and Crop Plant Research (IPK), they produced barley lines where both copies were disabled. These lines developed more grains per plant in the greenhouse.

Together with Freie Universität Berlin, Agroscope is now rolling out the trials into fields.

Alongside investigating if disabling the two genes increases yields, researchers also want to know if both copies of the gene need be disabled, or is knocking out one sufficient.

Secondly does disabling one or both copies of the gene modify other characteristics besides yield when grown in field conditions?

In the trails, researchers will disable either one or both copies of the CKX2 gene in various barley lines using the precise CRISPR/Cas9 technique.

Unlike other breeding techniques, the barley lines produced in this manner contain no foreign DNA. Although such an alteration could also occur via random natural mutation, these barley lines in Switzerland are treated as genetically modified plants (GMPs), since a novel technique is being applied that modifies the plant genome – hence the field trial’s need for the authorisation of the Federal Office for the Environment.

Trials from spring 2024 onwards

For practical reasons, research is being conducted with the old malting barley variety Golden Promise, which is not cultivated in Switzerland. This variety is comparatively easy to genetically alter, and is thus often used in research.

However, the knowledge gleaned from the trials will also be applicable to modern varieties of barley and, with good prospects of success, to additional cereal species such as wheat.

The regulation of plants from breeding techniques such as CRISPR/Cas9 is currently being discussed in various countries.

According to a first ruling of the EU Parliament last week, plants which could also arise by chance in nature without foreign DNA are to be less strictly regulated in future. The Swiss Federal Council is expected to submit proposals as to how it envisages the future authorisation scheme for such GMPs in mid-2024.