Mechanisms of tolerance to herbivore damage:what do we know?
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Identifying mechanisms of tolerance to herbivore damage will facilitate attempts to understand the role of tolerance in the evolutionary and ecological dynamics of plants and herbivores. Investigations of the physiological and morphological changes that occur in plants in response to herbivore damage have identified several potential mechanisms of tolerance. However, it is unlikely that all physiological changes that occur following damage are tolerance mechanisms. Few studies have made direct comparisons between the expression of tolerance and the relative expression of putative mechanisms. I briefly review empirical evidence for some of the better-studied potential mechanisms, including increased photosynthetic activity, compensatory growth, utilization of stored reserves, and phenological delays. For each of these mechanisms I discuss reasons why the relationship between tolerance and these characters may be more complicated than it first appears. I conclude by discussing several empirical approaches, including herbivore manipulations, quantitative trait loci (QTL) analysis, and selection experiments, that will further our understanding of tolerance mechanisms.
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- Crawley, M.J. (1983) Herbivory, the Dynamics of Animal-Plant Interactions. University of California Press, Berkley.Google Scholar
- Cook, C.W. and Stoddard, L.A. (1960) Physiological responses of big sagebrush to different types of herbage removal. J. Range Mgmt. 13, 14-16.Google Scholar
- Danckwerts, J.E. and Gordon, A.J. (1987) Long-term partitioning, storage, and re-mobilization of 14C assimilated by Lolium perenne (cv. Melle). Ann. Bot. 59, 55-66.Google Scholar
- Davidson, J.L. and Milthorpe, F.L. (1966) The effect of defoliation on the carbon balance in Dactylis glomerata. Ann. Bot. 30, 185-198.Google Scholar
- English-Loeb, G.M. and Karban, R. (1992) Consequences of variation in flowering phenology for seed head herbivory and reproductive success in Erigeron glaucus (Compositae). Oecologia 89, 588-595.Google Scholar
- Inouye, D.W. (1982) The consequences of herbivory: a mixed blessing for Jurinea mollis (Asteraceae). Oikos 39, 269-290.Google Scholar
- Karban, R. and Baldwin, I.T. (1997) Induced Responses to Herbivory. The University of Chicago Press, Chicago.Google Scholar
- Rausher, M.D. (1992a) Natural selection and the evolution of plant-insect interactions. In B.D. Roitberg and M.S. Isman, (eds) Insect Chemical Ecology: and Evolutionary Approach. Routledge, Chapman and Hall, New York, pp. 20-88.Google Scholar
- Ryle, G.J.A. and Powell, C.E. (1975) Defoliation and regrowth in the graminaceous plant: the role of current assimilate. Ann. Bot. 39, 297-310.Google Scholar
- Trlica, M.J. Jr. and Cook, C.W. (1971) Defoliation effects on carbohydrate reserves of desert species. J. Range Mgmt. 24, 418-425.Google Scholar
- Van der Meijden, E., Wijn, M. and Verkaar, H.J. (1988) Defense and regrowth, alternative plant strategies in the struggle against herbivores. Oikos 51, 355-363.Google Scholar
- Welter, S.C. (1989) Arthropod impact on plant gas exchange. In E.A. Bernays (ed.) Insect-Plant Interactions, vol. 1. CRC Press, Boca Raton, FL, pp. 135-150.Google Scholar
- Whitham, T.G., Maschinski, J., Larson, K.C. and Paige, K.N. (1991) Plant responses to herbivory: the continuum from negative to positive and underlying physiological mechanisms. In P.W. Price, T.M. Lewisohn, G.W. Fernandes and W.W. Bensons (eds) Plant-Animal Interactions: Evolutionary Ecology in Tropical and Temperate Regions. John Wiley and Sons, New York.Google Scholar