Genetic editing for a more productive and sustainable wood

The edition genetics has been used to breed poplars with reduced levels of lignin, a substance from floors which is the main obstacle for the sustainable production of fibers of wood.

Researchers coordinated by the State University of North Carolina (USA) describe in Science the procedure that “It promises to make the production of fibers for all kinds of products, from paper to diapers, greener, cheaper and more efficient”depending on the educational center.

Demand for wood fibers is on the rise to make renewable fabrics, paper, packaging, textiles, but their sustainable production is hampered by lignin.

This polymer gives plants the ability to grow in height, protects against ultraviolet radiation and attack by microorganisms, but its chemical and structural properties are also the reason why it is very difficult to break.

For fiber production to occur, lignin has to be cleaved and dissolved. Thanks to genetic editing with the CRISPR tool, scientists have designed a wood in which that substance is more suitable for fiber production.

The authors used their approach to generate a modified wood composition in a species of poplar, and the results set the stage for greater efficiency in obtaining fiber pulp, the experts say.

“Edited wood alleviates a major bottleneck in fiber production (…) and could bring unprecedented operational efficiencies, bioeconomic opportunities and environmental benefits”say the study authors.

Using machine learning to set lignin reduction targets, the team selected nearly 70,000 gene-editing strategies targeting 21 genes, then selected the best seven that the models predicted would lead to trees that hit the chemical sweet spot. .

From these seven strategies, CRISPR gene editing was used to produce 174 poplar lines. Lignin reductions were more significant in trees with four to six gene edits.

Trees with three gene edits showed lignin reduction of up to one 32%however, actions on a single gene did not manage to lower that substance much, which shows that the use of CRISPR to make multigenic changes could confer advantages in fiber production, indicates the aforementioned university.

The study also included sophisticated models of pulp mills suggesting that reducing lignin content in trees could increase pulp yield and reduce so-called black liquor, the main by-product of pulping, which could help plants produce up to a 40% more sustainable fibers.

Next steps include greenhouse trials to see how the GM trees perform compared to wild ones, and then field trials to determine if they can withstand the stresses of life outdoors.

This approach to tree improvement that combines genetics, computational biology, CRISPR tools, and bioeconomics “has profoundly expanded our knowledge of tree growth and development and forestry applications”said Daniel Sulis, first author of the article.

Besides, “It has transformed our ability to unravel the complexity of tree genetics and derive integrated solutions that could improve ecologically and economically important wood traits while reducing the carbon footprint of fiber production”.

Source: EFE