Lignification and tension wood.
Hardwood trees are able to reorient their axes owing to tension wood differentiation. Tension wood is characterised by important ultrastructural modifications, such as the occurrence in a number of species, of an extra secondary wall layer, named gelatinous layer or G-layer, mainly constituted of cellulose microfibrils oriented nearly parallel to the fibre axis. This G-layer appears directly involved in the definition of tension wood mechanical properties. This review gathers the data available in the literature about lignification during tension wood formation. Potential roles for lignin in tension wood formation are inferred from biochemical, anatomical and mechanical studies, from the hypotheses proposed to describe tension wood function and from data coming from new research areas such as functional genomics.
Pilate
Gilles
G
Unité INRA Orléans, av de la Pomme-de-Pin, BP 20 619 Ardon, 45166 Olivet cedex, France. pilate@orleans.inra.fr
Chabbert
Brigitte
B
Cathala
Bernard
B
Yoshinaga
Arata
A
Leplé
Jean-Charles
JC
Laurans
Françoise
F
Lapierre
Catherine
C
Ruel
Katia
K
D001696:Biomechanical Phenomena; D002473:Cell Wall / Q000235:genetics / Q000502:physiology*; D023281:Genomics; D008031:Lignin / Q000502:physiology*; D014934:Wood
D008031:Lignin