This study investigated the consequences of early season bud her bivory on host-plant phytochemistry and subsequent effects on a later midseason leaf-feeding herbivore, to test the hypothesis that temporally segregated interguild interactions could affect herbivore success through plant-mediated responses. Our system consisted of American basswood, Tilia americana, a bud-feeding thrips species, Thrips calcaratus, and the folivorous gypsy moth, Lymantria dispar. The impact of thrips bud-feeding on American basswood foliar chemistry and subsequent effects on gypsy moth larval preference and performance were measured. Foliar total nonstructural carbohydrates increased and phenolic levels decreased in response to bud injury, which affected larval feeding preference. In a two-choice test, gypsy moth larvae preferred leaf discs with high carbohydrate and low phenolic levels. The effects on larval performance depended on the extent of prior bud injury and were correlated with carbohydrate concentrations. In an early season assay, larval performance was lowest on moderately bud-damaged tissue, which also had the lowest total nonstructural carbohydrates. In a mid-season assay, larval performance and carbohydrate concentrations were highest in severely bud-damaged foliage. Foliar phenolics were highest in severely bud-damaged tissue in the early season assay, and in moderately damaged tissue in the mid-season assay. Gypsy moth performance was not correlated with foliar phenolic levels. Secondary (reflushed) foliage had higher carbohydrate levels than did primary (original) foliage, which correlated with increased larval performance. This study illustrates that bud-feeding herbivores can alter the phytochemistry and subsequent suitability of host-plant foliage for later folivores. The implications of these results to interactions between feeding guilds, community structure, and forest health are discussed.
|Number of pages||23|
|Journal||Journal of Chemical Ecology|
|State||Published - 1998|
Bibliographical noteFunding Information:
Acknowledgments—We thank R. Hines, R. Hofstetter, K. Montgomery, R. Schartman, D. Webb (University of Wisconsin), W. Kearby (Wisconsin Department of Natural Resources), and B. Burden (Louisiana State University-Shreveport) for technical assistance. A special thanks to K. Kinney for additional support. D. Hogg, D. Morris, T. Phillips, and E. Smalley (University of Wisconsin) reviewed an earlier version of the manuscript. The comments of two anonymousreview-ers greatly strengthened the manuscript. This research was funded by the University of Wisconsin-Madison College of Agricultural and Life Sciences, Wisconsin Department of Natural Resources, U.S. Forest Service, and McIntire-Stennis project WIS 03014.
- Bud injury
- Feeding guilds
- Gypsy moth
- Host preference
- Lymantria dispar
- Plant-insect interactions
ASJC Scopus subject areas
- Ecology, Evolution, Behavior and Systematics