Triphysaria pusilla (Orobanchaceae) - Xylembro
Photographer: H S Heide-Jørgensen

Transversal section of a single stranded xylem bridge in a small secondary haustorium of the root parasite T. pusilla from North-America. The water conducting xylem element with secondary lignified wall-thickenings is seen in the centre. It is surrounded by 'flange-walled' parenchyma cells assumed to function as transfer cells fascilitating transfer of nutrients across the cell walls in common with the xylem bridge.

Tværsnit af en enkeltstrenget xylembro i et lille sekundært haustorium af rodparasitten T. pusilla fra N-America. Det vandførende xylemelement med sekundære forveddede vægfortykkelser ses i midten omgivet af flange-parenchym celler. Disse formodes at fungere som transfer celler, der befordrer transport af næringsioner på tværs af de fortyk-kede vægge ind mod xylembroen.

See also Heide-Jørgensen & Kuijt 1995 - Abstract 29.

Photograph from Henning S. Heide-Jørgensen 2008: Parasitic flowering plants. - Dansk præsentation.