REDUCED LIGNIN IN TRANSGENIC PLANTS CONTAINING A CAFFEIC ACID O-METHYLTRANSFERASE ANTISENSE GENE

Lignin is a major structural polymer of secondarily thickened plant vascular tissue and fibres, imparting mechanical strength to stems and trunks and hydrophobicity to conducting vessels. Constitutive expression of a lucerne caffeic acid 3-O-methyltransferase antisense RNA in transgenic tobacco leads to a significant reduction in lignin content, particularly in the younger parts of the stems, without apparent alterations in lignin monomer composition. These observations open up the possibility of genetically manipulating plants with reduced lignin for improved processing and biomass digestibility.