Project news New field trial with genetically modified poplars for the bioeconomy
VIB has applied for a new field trial with genetically modified poplars. The trees have a modified wood composition that allows the wood to be converted to sugars in a more efficient and more environmentally friendly way. The change in wood composition involves a reduction in lignin and an increase in cellulose, which makes processing the wood easier. The poplars were developed as part of ongoing research on improving wood as a raw material for a more circular economy at the VIB-UGent Center for Plant Systems Biology.
Wood is largely composed of three components: cellulose, hemicellulose and lignin. The first two are sugar polymers; these sugars are the raw material for the production of biodegradable materials and bioethanol. The lignin forms a kind of cement between the cellulose and hemicellulose fibers. A reduced amount of lignin and/or a changed composition of it make it easier to break down and thus make the wood more suitable for use as a renewable raw material.
To achieve the change in wood composition, the CSE gene in the poplars is suppressed by means of so-called RNA interference technology. This involves the introduction of a genetic construct into the hereditary material of the trees that causes the production of an RNA molecule that folds to form a double-stranded 'hairpin' RNA molecule. This molecule initiates a mechanism by which normal CSE-RNA molecules are degraded. These CSE-RNA molecules are an intermediate step in the process that leads from CSE gene to the CSE enzyme. So less CSE-RNA also means less CSE enzyme. And less CSE enzyme in turn results in less lignin being formed in the wood.
Changes in lignin composition also exist in nature
Changes in lignin composition in wood also occur in nature, but very rarely. For example, a black poplar was discovered in Europe and a pine in the United States that have acquired a similar change in wood composition through natural mutations. Transferring these mutations to fast-growing, adapted trees through classical breeding is possible, but is difficult and time-consuming. By genetically modifying poplars, we can achieve similar results much more quickly. At the same time, scientific know-how is created to screen natural populations of trees for their potential use in a bio-based economy in the future.
Until now, genetically modified trees have only been studied in a greenhouse and there they grow just like ordinary poplars. But that tells us little about how the trees will behave outdoors when exposed to weather, wind, and seasons. For this reason, it is necessary to conduct a field trial and find out whether the trees also grow normally in natural conditions and produce wood that is more degradable.
Dissemination of the genetically modified trait ruled out
The spread of genetically modified traits is eliminated in two ways: by removing flowers and by removing root cuttings. (1) By removing any flowers that may appear. In this case, these are female trees that cannot spread pollen, and since the trees will not grow old, the chances of flowers forming at all are very small. (2) By carefully removing root cuttings, even after the trial is complete.
Collaboration with ILVO
The permit has been applied for by VIB, but the trial will be conducted in practice in collaboration with ILVO. If the application is approved the trial will be conducted on ILVO fields in Wetteren.
Permit application made public
The permit application is available for public inspection from February 1, 2021 to March 3, 2021 via the Federal Public Health Service website and is also available for inspection at the Wetteren Town Hall during that period.
