New insights into bordered pit structure and cavitation resistance in angiosperms and conifers

The article discusses water transport in angiosperms and conifers, focusing on structural factors that influence a plant's resistance to xylem cavitation. Such cavitation increases resistance to water flow, places limits on gas exchange, and may lead to starvation or death of the plant. The paper describes the geometry, material components, and functions of the xylem. It notes that pit membranes facilitate water flow between cells, but restrict passage of gases and pathogens. The pit membranes also account for a large proportion of the hydraulic resistance exhibited by the xylem.