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Title: Use of an exotic host plant reduces viral burden in a native insect herbivore
Abstract Incorporation of exotic plants into the diets of native herbivores is a common phenomenon, influencing interactions with natural enemies and providing insight into the tritrophic costs and benefits of dietary expansion. We evaluated how use of an exotic plant, Plantago lanceolata , impacted immune performance, development and susceptibility to pathogen infection in the neotropical herbivore Anartia jatrophae (Lepidoptera: Nymphalidae). Caterpillars were reared on P. lanceolata or a native plant, Bacopa monnieri , and experimentally infected with a pathogenic virus, Junonia coenia densovirus. We found that virus‐challenged herbivores exhibited higher survival rates and lower viral burdens when reared on P. lanceolata compared to B. monnieri , though immune performance and development time were largely similar on the two plants. These findings reveal that use of an exotic plant can impact the vulnerability of a native herbivore to pathogen infection, suggesting diet‐mediated protection against disease as a potential mechanism facilitating the incorporation of novel resources.  more » « less
Award ID(s):
1929522
PAR ID:
10454175
Author(s) / Creator(s):
; ; ; ;
Date Published:
Journal Name:
Ecology Letters
Volume:
26
Issue:
3
ISSN:
1461-023X
Page Range / eLocation ID:
425 to 436
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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