Bordered pits in xylem of vesselless angiosperms and their possible misinterpretation as perforation plates

• DOI: 10.1111/pce.13014
• Publication Date: 2017-07-01T18:46:38Z
• Authors: Ya Zhang; Matthias Klepsch; Steven Jansen
• Keywords: Perforation

Vesselless wood represents a rare phenomenon within the angiosperms, characterizing Amborellaceae, Trochodendraceae and Winteraceae. Anatomical observations of bordered pits their pit membranes based on light, scanning transmission electron microscopy (SEM TEM) are required to understand functional questions surrounding vesselless angiosperms potential occurrence cryptic vessels. Interconduit in 11 species showed similar ultrastructure as mesophytic vessel-bearing with mean thickness 245 nm (± 53, SD; n = six species). Shrunken, damaged aspirated membranes, which were 52% thinner than fresh samples (n four species), occurred all dried-and-rehydrated samples, latewood Tetracentron sinense Trochodendron aralioides. SEM demonstrated that shrunken artificially enlarged, > 100 wide pores. Moreover, perfusion experiments stem segments Drimys winteri 20 50 colloidal gold particles only passed through 2 cm long segments, but not sized ones. These results indicate membrane shrinkage is irreversible associated considerable increase pore size. our findings suggest damage, may occur planta, could explain earlier records vessels angiosperms.