Researchers at the University of Maryland have achieved a groundbreaking advancement in sustainable construction by genetically modifying poplar trees to produce high-performance structural wood without the need for chemicals or energy-intensive processing. Traditionally, engineered wood—often seen as a renewable alternative to materials like steel, cement, glass, and plastic—requires significant processing with volatile chemicals and large amounts of energy, leading to considerable waste. This new development promises a more sustainable approach to producing engineered wood, with far-reaching implications for carbon sequestration and climate change mitigation.

The key innovation lies in editing a single gene in live poplar trees, enabling them to grow wood that is ready for engineering without the need for traditional processing. “We are very excited to demonstrate an innovative approach that combines genetic engineering and wood engineering, to sustainably sequester and store carbon in a resilient super wood form,” said Yiping Qi, a professor in the Department of Plant Science and Landscape Architecture at UMD and a corresponding author of the study. He emphasized the importance of carbon sequestration in the fight against climate change, highlighting the potential uses of this engineered wood in the future bioeconomy.

Engineered wood’s strength and durability come from removing lignin, one of its main components, before treating it to enhance structural properties such as increased strength and UV resistance. Previously, UMD researchers developed methods to remove lignin using chemicals, enzymes, and microwave technology. However, Qi and his team aimed to eliminate the reliance on chemicals and reduce energy consumption in the process.

By employing a technology called base editing, the researchers successfully knocked out a key gene, 4CL1, in the poplar trees. This resulted in a 12.8% reduction in lignin content—comparable to the effects achieved through chemical treatments. The genetically modified poplars were grown alongside unmodified trees in a greenhouse for six months, showing no difference in growth rates or structural integrity.

To test the viability of the genetically modified poplar, the research team, led by professor of materials science and engineering Liangbing Hu, produced small samples of high-strength compressed wood, similar to particle board commonly used in furniture. Compressed wood is created by soaking wood in water under a vacuum and then hot-pressing it until it reaches nearly one-fifth of its original thickness, increasing the density of the wood fibers. In natural wood, lignin helps maintain cell structure and prevents compression, but the lower lignin content in the genetically modified wood allows for higher density and strength.

The compressed wood made from genetically modified poplar was found to perform on par with chemically processed natural wood, both achieving densities and strengths more than 1.5 times higher than untreated natural wood. The tensile strength of the compressed genetically modified wood was comparable to that of aluminum alloy 6061, a material commonly used in construction.

This research opens new possibilities for producing a variety of building products in an environmentally sustainable and cost-effective manner, potentially playing a significant role in combating climate change. The innovative approach offers a pathway to large-scale production of engineered wood with minimal environmental impact, paving the way for its broader adoption in the construction industry.

By Impact Lab