Insect generalists

An illuminating example of a community consequence of plant defensive metabolites, and of a grazer s adaptation to exploit its host plant, is the ability of some herbivores to sequester plant-derived secondary metabolites for their own defenses (e.g., Avila 1995 Marin and Ros 2004). In terrestrial systems, several specialist insects can sequester defensive chemicals from their host plants (e.g., Nishida 2002), but in aquatic plant-herbivore systems with a prevalence of generalist herbivores this is less common. However, sea hares (Anaspidea) and some other herbivorous opisthobranch molluscs are known to be able to sequester defenses from their algal foods (Avila 1995 Marin and Ros 2004). For the opisthobranch species that are known to obtain metabolites from their food, algae were the... 

Bemays EA, Minkenberg OPJM (1997) Insect herbivores different reasons for being a generalist. Ecology 78 1157-1169... 

Thus, there is an interesting contrast between terrestrial and marine systems in the relationship between specialization and detoxification of secondary metabolites. Among terrestrial insects and mammals, specialists seem to be associated with chemically difficult plants (Berenbaum et al. 1996), while in marine systems, generalists tend to consume chemically rich plants (e.g., amphipods and fishes). 

Li X, Baudry J, Berenbaum MR, Schuler MA (2004) Structural and functional divergence of insect CYP6B proteins from specialist to generalist cytochrome P450. Proc Nat Acad Sci 101 2939-2944... 

Many Insects have become specialists on crucifers and a few related plant families. These Include flea beetles, leaf beetles, cabbage root fly, aphids, cabbage butterflies and the dlamondback moth. At the same time, several polyphagous Insects such as the cabbage looper, armyworms and aphids are major pests of crucifers. Comparative studies on these specialists and generalists have provided valuable Information on host recognition and possible resistance mechanisms. 

Diversified suite of specialist and generalist insects Soft, because of a polygenic resistance High... 

Hagele, B. F. and Rowell-Rahier, M. (2000). Choice, performance, and heritability of performance of specialist and generalist insect herbivores towards cacalol and seneciphylline, two allelochemics of Adenostyles alpina (Asteraceae). Journal of Evolutionary Biology 13 131-142. 

Nomura M, Itioka T. 2002. Effects of synthesized tannin on the growth and survival of a generalist herbivorous insect, the common cutworm, Spodoptera litura Fabricius (Lepidoptera Noctuidae). Appl Entomol Zool 37 285-289. 

GLUCOSINOLATE HYDROLYSIS AND ITS IMPACT ON GENERALIST AND SPECIALIST INSECT HERBIVORES... 

YU, S.J., Microsomal oxidation of allelochemicals in generalist (Spodoptera Jrugiperda) and semispecialist (Anticarsia gemmatalis) insects., J. Chem. Ecol, 1987,13, 423-436. 

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