title: Gibberellin-induced formation of tension wood in angiosperm trees.
abstract: After gibberellin had been applied to the vertical stems of four species of angiosperm trees for approximately 2 months, we observed eccentric radial growth that was due to the enhanced growth rings on the sides of stems to which gibberellin had been applied. Moreover, the application of gibberellin resulted in the formation of wood fibers in which the thickness of inner layers of cell walls was enhanced. These thickened inner layers of cell walls were unlignified or only slightly lignified. In addition, cellulose microfibrils on the innermost surface of these thickened inner layers of cell walls were oriented parallel or nearly parallel to the longitudinal axis of the fibers. Such thickened inner layers of cell walls had features similar to those of gelatinous layers in the wood fibers of tension wood, which are referred to as gelatinous fibers. Our anatomical and histochemical investigations indicate that the application of gibberellin can induce the formation of tension wood on vertical stems of angiosperm trees in the absence of gravitational stimulus.
authors.affiliation: Faculty of Agriculture, Tokyo University of Agriculture and Technology, Fuchu-Tokyo, 183-8509, Japan. funada@cc.tuat.ac.jp
authors.forename: Ryo
authors.initials: R
authors.lastname: Funada
authors.forename: Tatsuhiko
authors.initials: T
authors.lastname: Miura
authors.forename: Yousuke
authors.initials: Y
authors.lastname: Shimizu
authors.forename: Takanori
authors.initials: T
authors.lastname: Kinase
authors.forename: Satoshi
authors.initials: S
authors.lastname: Nakaba
authors.forename: Takafumi
authors.initials: T
authors.lastname: Kubo
authors.forename: Yuzou
authors.initials: Y
authors.lastname: Sano
mesh_terms: D005875:Gibberellins / Q000494:pharmacology*; D019684:Magnoliopsida / Q000187:drug effects / Q000254:growth & development; D010937:Plant Growth Regulators / Q000494:pharmacology; D018547:Plant Stems / Q000187:drug effects / Q000254:growth & development; D029963:Quercus / Q000187:drug effects / Q000254:growth & development; D014197:Trees / Q000187:drug effects / Q000254:growth & development*; D014934:Wood / Q000187:drug effects / Q000502:physiology*
chemical_list: D005875:Gibberellins; D010937:Plant Growth Regulators; C007842:gibberellic acid