Developmental anatomy and branching of roots of four Zeylanidium species (podostemaceae), with implications for evolution of foliose roots.

ABSTRACT: Podostemaceae have markedly specialized and diverse roots that are adapted to extreme habitats, such as seasonally submerged or exposed rocks in waterfalls and rapids. This paper describes the developmental anatomy of roots of four species of Zeylanidium, with emphasis on the unusual association between root branching and root-borne adventitious shoots. In Z. subulatum and Z. lichenoides with subcylindrical or ribbon-like roots, the apical meristem distal (exterior) to a shoot that is initiated within the meristem area reduces and loses meristematic activity. This results in a splitting into two meristems that separate the parental root and lateral root (anisotomous dichotomy). In Z. olivaceum with lobed foliose roots, shoots are initiated in the innermost zone of the marginal meristem, an

SUBMITTER: Hiyama Y 

PROVIDER: S-EPMC4240370 | biostudies-literature | 2002 Dec

REPOSITORIES: biostudies-literature