Pilate G, Guiney E, Holt K, Petit-Conil M, Lapierre C, Leplé JC, Pollet B, Mila I, Webster EA, Marstorp HG, Hopkins DW, Jouanin L, Boerjan W, Schuch W, Cornu D, and Halpin C
Subjects
Alcohol Oxidoreductases genetics, Alcohol Oxidoreductases metabolism, Antisense Elements (Genetics), Ecosystem, Environmental Pollution prevention & control, France, Gene Expression, Industrial Waste prevention & control, Methyltransferases genetics, Methyltransferases metabolism, Models, Chemical, Paper, Plant Roots metabolism, Reproducibility of Results, Sensitivity and Specificity, Soil Microbiology, Transgenes, United Kingdom, Lignin genetics, Lignin metabolism, Plants, Genetically Modified, Populus genetics, Populus metabolism, Wood
Abstract
The agronomic and pulping performance of transgenic trees with altered lignin has been evaluated in duplicated, long-term field trials. Poplars expressing cinnamyl alcohol dehydrogenase (CAD) or caffeate/5-hydroxy-ferulate O-methyltransferase (COMT) antisense transgenes were grown for four years at two sites, in France and England. The trees remained healthy throughout the trial. Growth indicators and interactions with insects were normal. No changes in soil microbial communities were detected beneath the transgenic trees. The expected modifications to lignin were maintained in the transgenics over four years, at both sites. Kraft pulping of tree trunks showed that the reduced-CAD lines had improved characteristics, allowing easier delignification, using smaller amounts of chemicals, while yielding more high-quality pulp. This work highlights the potential of engineering wood quality for more environmentally benign papermaking without interfering with tree growth or fitness.