FIBERS AND FIBER-SCLEREIDS IN WILD-TYPE ARABIDOPSIS-THALIANA

Examination of the fibre system in roots and shoots of Arabidopsis tha liana (L.) Heynh. revealed three types of fibres, distinguished accord ing to their site of differentiation: (1) short fibre-sclereids in the secondary phloem of roots and shoots at the rosette level; (2) long f ibres in the secondary xylem of the main root; and (3) very long fibre s in the xylem of the inflorescence stems. These three types are in ad dition to the small number of primary phloem fibres that are formed ev en in small A. thaliana individuals. These findings provide a basis fo r the use of Arabidopsis thaliana as a model system to study the proce sses leading to fibre differentiation in dicotyledons. (C) 1997 Annals of Botany Company.