2.3.1 Sampling and processing of leaf material
Leaves were carefully excised from the plants and transported in zip-lock bags. The first batch of leaf material was used fresh for a general characterization of leaf surfaces. Additional batches of leaves were collected, and areas of interest (see Table 2 ) isolated using a scalpel, which were then immersed in 4% (w/v) paraformaldehyde in phosphate-buffered saline (PBS) for 1 h under vacuum, and then overnight at 4°C. This fixed leaf material was used for vibratome and ultramicrotome sectioning.