Edge-effect fragmentation in the context of foliar disease transmission

Rain-induced foliar pathogen propagation is inherently
linked to raindrop fragmentation upon impact on infected leaves. Close
to leaf edges, the outcome of a drop impact is complex and asymmet-
ric. Despite the ubiquitous nature of impacts close to edges, little is
known on the role of edges in shaping drop fragmentation (edge-effect
fragmentation). To address this gap, we present a series of drop impact
experimental results with impact point close to the surface edge. We
focus on the liquid sheet expansion in the air and the role of the edge in
introducing the asymmetry in such expansion. We link the edge-induced
asymmetry of the sheet to the emergence of different families of droplet-
producing fragmentation processes. We discuss how our results can help
shed light on foliar disease transmission.