Biochemical Peradaptations, Founder Events, and the Evolution of Resistance in Arthropods

Abstract

We conducted literature-based comparative analyses of pesticide resistance evolution to evaluate 2 aspects of microevolutionary response to strong novel selection pressun's. First, it has been proposed that herbivorous arthropods are preadapted to evolve resistance by a system of detoxifying enzymes the evolution of which was elaborated in response to plant defensive chemicals. To test this hypothesis, we note that arthropods that feed on plant vascular tissues (phloem and xylem, which are less strongly chemically defended than other tissues) have lower levels of detoxifying enzyme activities than species that chew or feed on cell contents, and might therefore be expected to be less strongly preadapted to pesticides. The record of pesticide resistance evolution in 615 arthropod pests of North American agriculture is consistent with the biochemical pre adaptation hypothesis; phloem-and xylem-feeding species have a significantly diminished ability to evolve resistance when compared with eitller chewing or cell content-feeding species. The same result is obtained in an analysis restricted to species within the order Homoptera. We caution, however, that feeding behavior is confounded with taxonomy in these analyses; thus, strong inferences of a causal relationship between feeding mode and resistance evolution would be premature. Second, conventional theory suggests t11at population bottlenecks that occur during the initiation of geographically isolated populations can have profound effects on the genetic structure of populations, including particularly the loss of allelic diversity. Arthropods that have been introduced to North America, and thus have undergone founder events, might therefore be expected to be depauperate for key resistance-conferring genetic variants. Our analyses find no support for this founder event hypothesis; native and introduced species do not differ significantly in resistance evolution. We evaluate the importance of possibly confounding variables in the interpretation of these results and emphasize the need to integrate experimental results with these comparative broad-scale results.

A link between host plant adaptation and pesticide resistance in the polyphagous spider mite Tetranychus urticae

“…In a polyphagous pest such as the spider mite, such modules of coregulated genes may provide an explanation for the common transcriptional patterns of MR-VP, MAR-AB, and Tomato-5G. In this sense, when polyphagy is seen as genetic polymorphism in the response to different chemical environments, it may represent a preadaptation to xenobiotic resistance as suggested previously (10,12). The selection of the rare resistance allele to the acaricide would be facilitated by the initial, higher survival rate of a subset of the population harboring it.…”

“…10, p. 30). The "preadaptation hypothesis" for insecticide resistance has been supported by surveys of the literature (11,12) although the comparisons drawn between herbivores and natural enemies or between chewing and sucking herbivores may be confounded by taxonomy, thus calling for other forms of experimental and observational evidence (12). It is now well accepted that herbivore exposure to different plant allelochemicals can affect the toxicity of pesticides (13)(14)(15)(16)(17)(18)(19)(20)(21)(22)(23)(24)(25).…”

The population ecology of contemporary adaptations: What empirical studies reveal about the conditions that promote adaptive evolution

“…Similarly, the evolution of heavy metal tolerance and insecticide resistance has been documented in hundreds of species around the world (e.g. Antonovics, Bradshaw & Turner, 1971;Mallet, 1989;Macnair, 1991a;Rosenheim et al, 1996). Because these topics have been reviewed in depth elsewhere, we have represented each of them with just a few representative papers and reviews and consider these sufficient to represent these forms of adaptations.…”

“…Physiological characters included salinity tolerance in copepods (Lee, 1999), heavy metal tolerance in plants and animals (Antonovics, Bradshaw & Turner, 1971;Klerks & Weis, 1987;MacNair, 1987), insecticide resistance (Rosenheim et al 1996), and thermal tolerance (Holland et al, 1974;Hendry, Hensleigh & Reisenbichler, 1998).…”

Management Strategies for Western Flower Thrips and the Role of Insecticides

“…Because individuals move from host to host, they are likely to encounter a variety of plant defensive chemicals. Therefore, it is adaptive to have multiple means to contend with the unpredictable suite of host plant defenses that they may encounter (Rosenheim et al, 1996). These inherent metabolic detoxification pathways predispose the western flower thrips to overcome pyrethroids and other classes of insecticides.…”