Figure 6
Scanning electron micrographs of the surface topology of CAP treated (left) or LEEB treated (right) lentil seeds. Scale bars represent 1 µm. Time of plasma exposure is indicated in the top left or right corner of the images. White arrows indicate embedded debris observed between the papillae of untreated seeds used as control. While seeds exposed to 60 s of CAP treatment revealed visible concave pits that were cleared from such debris, even high dose electron beam treatment did not remove the debris lodged between the protruding structures on the lentil seed surface. After 180 s CAP treatment, the seed surface revealed erosion of the protruding structures. The middle part of the figure displays the impact of CAP (left) or LEEB (right) treatment on the wettability of the lentil seeds shown with water droplet and contact angle measurements. Untreated control seeds showed a hydrophobic surface. While the surface of CAP treated seeds became hydrophilic, LEEB treated seeds maintained hydrophobic surface characteristics. SEM images provided by Stephan Handschin, CC by 4.0.
