2.4 Leaf surface wettability
Three fresh leaves per species were carefully excised from the plants
and used as replicates. For each species, the area of interest (seeTable 2 ) was isolated using a scalpel so that it would lie as
flat as possible on the stage. Leaf surface wettability was assessed by
measuring the contact angle (θC) in a tensiometer fitted
with a high-speed camera (Attension Theta optical tensiometer, Biolin
Scientific AB), using the sessile drop method. A 5 μl droplet of
dH2O (as suggested by Matos and Rosado 2016) was placed
on the leaf surface by the tensiometer and the θC was
recorded for 10 seconds (14 FPS). The resulting static
θC was measured using the Young-Laplace fit.