Oecologia (2014) 174, 883-892
Mônica F. Kersch-Becker and Jennifer S. Thaler (2014)
Virus strains differentially induce plant susceptibility to aphid vectors and chewing herbivores
Oecologia 174 (3), 883-892
Abstract: Plants are frequently attacked by both pathogens and insects, and an attack from one can induce plant responses that affect resistance to the other. However, we currently lack a predictive framework for understanding how pathogens, their vectors, and other herbivores interact. To address this gap, we have investigated the effects of a viral infection in the host plant on both its aphid vector and non-vector herbivores. We tested whether the infection by three different strains of Potato virus Y (PVYNTN, PVYNO and PVYO) on tomato plants affected: (1) the induced plant defense pathways; (2) the abundance and fecundity of the aphid vector (Macrosiphum euphorbiae); and (3) the performance of two non-vector species: a caterpillar (Trichoplusia ni) and a beetle (Leptinotarsa decemlineata). While infection by all three strains of PVY induced the salicylate pathway, PVYNTN induced a stronger and longer response. Fecundity and density of aphids increased on all PVY-infected plants, suggesting that the aphid response is not negatively associated with salicylate induction. In contrast, the performance of non-vector herbivores positively correlated with the strength of salicylate induction. PVYNTN infection decreased plant resistance to both non-vector herbivores, increasing their growth rates. We also demonstrated that the impact of host plant viral infection on the caterpillar results from host plant responses and not the effects of aphid vector feeding. We propose that pathogens chemically mediate insect-plant interactions by activating the salicylate pathway and decreasing plant resistance to chewing insects, which has implications for both disease transmission and insect community structure.
(The abstract is excluded from the Creative Commons licence and has been copied with permission by the publisher.)
Link to article at publishers website
Database assignments for author(s): Jennifer S. Thaler
Research topic(s) for pests/diseases/weeds:
transmission/dispersal of plant diseases
Pest and/or beneficial records:
| Beneficial | Pest/Disease/Weed | Crop/Product | Country | Quarant.
|
|---|---|---|---|---|
| Macrosiphum euphorbiae | ||||
| Potato virus Y |
