Adult Diabroticites including western corn rootworm (WCR), Diabrotica virgifera virgifera LeConte, consume pollen of corn, squash, sunflower, and other species. Short-chain neutral amino acids in methanol-water extracts of pollen have been previously identified in our laboratory as strong phagostimulants for Diabrotica. Bioassay-driven fractionation was used to characterize the interacting lipid and midpolarity phagostimulants for adult WCR in Giant Gray Stripe sunflower, Helianthus annuus L., pollen. Lipids rich in ω3-linolenic acid including triglycerides, free fatty acids, phosphatidylethanolamines, phosphatidic acids, and phosphatidylcholines were highly phagostimulatory. Other important phagostimulatory components included a hydroxycinnamic acid-polyamine amide, N',N5,N10-tri[(E)-p- coumaroyl]spermidine, and a flavonol, quercetin β-3-O-glucoside. The structural characteristics of these phagoactive compounds and their role in the pollinivory specialization of rootworm beetles are discussed.
All Science Journal Classification (ASJC) codes
- Agricultural and Biological Sciences(all)