Article (Scientific journals)
Fluid fragmentation shapes rain-induced foliar disease transmission
Gilet, Tristan; Bourouiba, Lydia
2015In Journal of the Royal Society, Interface, 12
Peer Reviewed verified by ORBi
 

Files


Full Text
2015-JRSI.pdf
Author postprint (9.03 MB)
Download

All documents in ORBi are protected by a user license.

Send to



Details



Keywords :
Foliar diseases; Epidemiology; Droplets; Surface tension; Leaf mechanics
Abstract :
[en] Plant diseases represent a growing threat to the global food supply. The factors contributing to pathogen transmission from plant to plant remain poorly understood. Statistical correlations between rainfalls and plant disease out- breaks were reported; however, the detailed mechanisms linking the two were relegated to a black box. In this combined experimental and theoretical study, we focus on the impact dynamics of raindrops on infected leaves, one drop at a time. We find that the deposition range of most of the pathogen-bear- ing droplets is constrained by a hydrodynamical condition and we quantify the effect of leaf size and compliance on such constraint. Moreover, we identify and characterize two dominant fluid fragmentation scenarios as responsible for the dispersal of most pathogen-bearing droplets emitted from infected leaves: (i) the crescent-moon ejection is driven by the direct interaction between the impacting raindrop and the contaminated sessile drop and (ii) the inertial detachment is driven by the motion imparted to the leaf by the raindrop, lead- ing to catapult-like droplet ejections. We find that at first, decreasing leaf size or increasing compliance reduces the range of pathogen-bearing droplets and the subsequent epidemic onset efficiency. However, this conclusion only applies for the crescent moon ejection. Above a certain compliance threshold a more effective mechanism of contaminated fluid ejection, the inertial detachment, emerges. This compliance threshold is determined by the ratio between the leaf velocity and the characteristic velocity of fluid fragmentation. The inertial detachment mechanism enhances the range of deposition of the larger con- taminated droplets and suggests a change in epidemic onset pattern and a more efficient potential of infection of neighbouring plants. Dimensionless parameters and scaling laws are provided to rationalize our observations. Our results link for the first time the mechanical properties of foliage with the onset dynamics of foliar epidemics through the lens of fluid fragmentation. We discuss how the reported findings can inform the design of mitigation strategies acting at the early stage of a foliar disease outbreak.
Disciplines :
Engineering, computing & technology: Multidisciplinary, general & others
Author, co-author :
Gilet, Tristan  ;  Université de Liège - ULiège > Département d'aérospatiale et mécanique > Microfluidique
Bourouiba, Lydia;  Massachusetts Institute of Technology - MIT > Civil & Environmental Engineering
Language :
English
Title :
Fluid fragmentation shapes rain-induced foliar disease transmission
Publication date :
2015
Journal title :
Journal of the Royal Society, Interface
ISSN :
1742-5689
eISSN :
1742-5662
Publisher :
Royal Society
Volume :
12
Peer reviewed :
Peer Reviewed verified by ORBi
Available on ORBi :
since 14 April 2015

Statistics


Number of views
115 (16 by ULiège)
Number of downloads
175 (15 by ULiège)

Scopus citations®
 
82
Scopus citations®
without self-citations
70
OpenCitations
 
68

Bibliography


Similar publications



Contact ORBi