Rootworm, western com

The com rootworms Diabrotica barberi and D. virgijera were controUed in the U.S. com belt from 1954 to 1964 by soil appHcations of heptachlor and aldrin. A resistant race of the western com rootworm D. virgijera was first characterized in southeastern Nebraska in 1961 and spread rapidly throughout the entire com belt. Successive introductions of carbamate and organophosphate soil insecticides have increased the cost of com rootworm control from... 

The Diabrotica spp. com rootworm beetles are specifically attracted to a variety of plant-produced phenylpropanoids, eg, ( )-cinnamaldehyde [14371-10-9] for the southern com rootworm D. undecimpunctata howardr, ( )-cinnamyl alcohol [4407-36-7] for the northern com rootworm D. barberi and indole [120-72-9] for the western com rootworm, D. virgifera virgifera. Especially powerflil lures for these rootworm beetles are 2-(4-methoxyphenyl)ethanol for the northern com rootworm and 4-methoxycinnamaldehyde [71277-11-7] (177) for the western com bootworm. 

Lin, S. and Mullin, C.A., Lipid, polyamide and flavonol phagostimulants for the adult Western com rootworm from sunflower pollen, J. Agric. Food Chem., 47, 1223, 1999. 

The foregoing matters bring up the point that the com crop in the United States for the most part comprises a monoculture, and increasingly (or pervasively) consists of genetically modified subspecies. This may conceivably make the com crop more receptive to attack by the western com rootworm beetle, or still other unexpected pests. In other words, there is the need, or make it a necessity, for diverse species or subspecies rather than having a uniform monoculture. It is the old saw about not putting all of one s eggs in one basket. 

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. 

Table IV. Floral Feeding Deterrents for Adult Western Com Rootworm Among Ethyl Acetate Soluble Chemicals from the Sunflower ...

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). 

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