Diabrotica virgifera

The entire subject has been reviewed in detail several times.32,56,57,65 Recently, a new adsorptive method for the isolation of DIMBOA has been reported.49 The impact of benzoxazinoids on the western corn rootworm (Diabrotica virgifera LeConte) development has been studied.17 The allocation of a hydroxamic acid and biomass during vegetative development of rye has been investigated.27 Effects of benzoxazinoids from maize on survival and fecundity of aphids have been explored.13 DIMBOA concentrations have been measured in various isolines of wheat and corresponding plant introduction lines.55 The variation of the content of several benzoxazinoids in relation to the age and plant organ has been determined in maize plants.12... 

The blossoms of Cucurbitaceae are well known to be highly attractive to many species of Diabrotica beetles. However, the volatile compounds that act as attractants differ in different Diabrotica species. Cinnamaldehyde strongly attracts the spotted cucumber beetle, Diabrotica undecimpunctata hoivardi, whereas 4-methoxycinnamaldehyde is a specific attractant for the western corn rootworm, Diabrotica virgifera virgifera.51 The northern corn rootworm, Diabrotica barberi, and Diabrotica cristata are attracted to eugenol, cinnamyl alcohol, and 2-(4-methoxyphenyl)ethanol. Volatiles of maize, one of the host plants, also attract D. v. virgifera... 

Figure 11 Feeding stimulants for Diabrotica virgifera virgifera identified from maize and sunflower pollen.

Hollister B, MuUin CA (1999) Isolation and identification of primary metabolite feeding stimulants for adult western corn rootworm, Diabrotica virgifera virgifera Leconte, from host pollens. J Chem Ecol 25 1263-1280... 

Toxicity of the compounds was examined in four types of insects house fly (Musca domestica), mosquito (Aedes aegypti), corn rootworm beetles (Diabrotica virgifera virgifera and Diabrotica undecimpunctata howardi) and the German cockroach (Blattella... 

Another important member of this family is the western corn rootworm, Diabrotica virgifera virgifera LeConte. Our research with this insect s sex pheromone gave ample indication that much can be learned both by biologists and chemists if a project to identify chemical cues is not focused solely on a designated pest species, but is instead broadened to encompass closely related species. 

Cucurbitacin B evokes chemosensory responses at levels as low as 0.1 uM, probably acting at a different modulatory site than do classical synaptic y-aminobutyric acid (GABA) and glycine receptor-channel complexes. Chyb et al. [83] studied adult western com rootworm (Diabrotica virgifera virgifera, Coleoptera-Chrysomelidae) beetles and reported the possibility that there are peripheral chemosensory receptor sites that may resemble, both functionally and structurally, synaptic receptor sites in the CNS. 

The toxicity of compounds 27-31 on L. decemlineata was inversely correlated to their antifeedant effects and directly related to their polarity, suggesting a different mode of action or receptor affinity at the central nervous system [20], A similar correlation has been shown between antifeedant effects, toxicity and polarity of structurally-related silphinene sesquiterpenes on CPB and Diabrotica virgifera virgifera [19, 36]. Such a lack of behavioral and toxicity relationship has been noted for a broad selection of plant allelochemicals [43-46]. 

Lampman, R. L., R. L. Metcalf, and J. F. Andersen, Semiochemi-cal attractants of Diabrotica undecimpunctata howardii Barber, southern com rootworm, and Diabrotica virgifera virgifera Leconte, the western com rootworm (Coleoptera Chrysomelidae), J. Chem. Ecol., 13, 959-975 (1987). 

Abscisic acid is a sequiterpene phytohormone that is induced by drought and promotes stomatal closure and seed dormancy. Other sesquiterpenes take part in tritrophic plant-herbivore-parasite interactions (reviewed by Dudareva et al., 2006). In maize infested with lepidopteran larvae, the sesquiterpenes ( )-P-famesene and the ( )-a-bergamotene (Fig. 30) attract the parasitic wasp Cotesia marginiventris (Schnee et al., 2006). Maize roots release ( )-P-caryophyllene (Fig. 30) upon attack of larvae of the beetle Diabrotica virgifera to attract the parasitic nematode Heterorhabditis megidis (Rasmann et al., 2005). 

Ellis, R.T., B.A. Stockhoff, L. Stamp, H.E. Schnepf, G.E. Schwab, M. Kunth, J. Russell, G.A. Cardineau, and K.E. Narva. 2002. Novel Bacillus thuringiensis binary insecticidal crystal proteins active on western corn rootwoom, Diabrotica virgifera virgifera LeConte. App. Environ. Microbiol. 68 1137-1145. 

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