Title: | Bottom-up trait-mediated indirect effects decrease pathogen transmission in a tritrophic system |
Address: | "Department of Biological Sciences, Louisiana State University, Baton Rouge, Louisiana, 70803, USA" |
ISSN/ISBN: | 0012-9658 (Print) 0012-9658 (Linking) |
Abstract: | "A plant's induction of secondary defenses helps to decrease herbivore damage by changing resource quality. While these chemical or physical defenses may directly decrease herbivory, they can also have indirect consequences. In a tritrophic system consisting of a plant, an insect herbivore, and an insect pathogen, plant based trait-mediated indirect effects (TMIEs) can alter host-pathogen interactions and, thereby, indirectly affect disease transmission. In a series of field experiments, individual soybean plants (Glycine max) were sprayed with either a jasmonic acid (JA) solution to trigger induction of plant defenses or a similar control compound. Fall armyworm (Spodoptera frugiperda) larvae along with varying amounts of a lethal baculovirus were placed on the plants to measure transmission. Induction of plant defenses decreased viral transmission due to increased population heterogeneity arising from changes in individual susceptibility. The change in susceptibility via TMIEs was driven by a decrease in feeding rates and an increase viral dose needed to infect larvae. While the induction against herbivore attack may decrease herbivory, it can also decrease the efficacy of the herbivore's pathogen potentially to the plant's detriment. While TMIEs have been well-recognized for being driven by top-down forces, bottom-up interactions can dictate community dynamics and, here, epizootic severity" |
Keywords: | Animals *Fabaceae *Herbivory Host-Pathogen Interactions Larva Spodoptera Spodoptera frugiperda Baculovirus Bayesian analysis epizootics fall armyworm induced plant defenses variability in transmission rate; |
Notes: | "MedlineElderd, Bret D eng 1316334/NSF/International Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, Non-P.H.S. 2018/12/12 Ecology. 2019 Jan; 100(1):e02551. doi: 10.1002/ecy.2551. Epub 2018 Dec 11" |