Pathogen spread rates are determined, in part, by the performance of pathogens under altered environmental conditions and their ability to persist while switching among hosts and vectors. To determine the effects of new conditions (host, vector, and nutrient) on pathogen spread rate, we introduced a vector‐borne viral plant pathogen, Barley Yellow Dwarf Virus PAV (BYDV‐PAV) into hosts, vectors, and host nutrient supplies that it had not encountered for thousands of viral generations. We quantified pathogen prevalence over the course of two serial inoculations under the new conditions. Using individual‐level transmission rates from this experiment, we parameterized a dynamical model of disease spread and projected spread across host populations through a growing season. A change in nutrient conditions (increased supply of phosphorus) reduced viral transmission whereas shifting to a new vector or host species had no effect on infection prevalence. However, the reduction in the new nutrient environment was only temporary; infection prevalence recovered after the second inoculation.
The endophyte
Along the Appalachian Mountains from North Carolina to New York, USA.
Fungi.
Studied correlations of infection frequencies with abiotic and biotic environmental factors. Checked endophyte vertical transmission rates and effects on overwintering survival. With artificial inoculations for two host populations with two isolates per endophyte species, tested endophyte–host compatibility. Studied effects of isolates on host performances in greenhouse experiment with four water‐nutrients treatments.
Correlation analysis revealed positive associations of
In the absence of clear and consistent effects of the endophytes on host growth, the differences in endophyte‐mediated protection against herbivores may be the key factor determining distribution differences of the two endophyte species.
- NSF-PAR ID:
- 10460021
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Ecology and Evolution
- Volume:
- 9
- Issue:
- 11
- ISSN:
- 2045-7758
- Page Range / eLocation ID:
- p. 6624-6642
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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