Survival and development of a stored-product pest, Sitophilus zeamais (Coleoptera: Curculionidae), and its natural enemy, the parasitoid Lariophagus distinguendus (Hymenoptera: Pteromalidae), on transgenic Bt maize

Pest Manag Sci. 2013 May;69(5):602-6. doi: 10.1002/ps.3410. Epub 2012 Oct 9.

Abstract

Background: The effect of transgenic maize (Zea mays L.) containing a lepidopteran-specific Bt toxin on a stored-product pest, Sitophilus zeamais Motschulsky, and its parasitoid, Lariophagus distinguendus Förster, was examined in the laboratory to test the impact of transgenic maize on stored-product pests and their biological control.

Results: Weevils were not harmfully affected by transgenic Bt maize in their development characteristics (development time, body mass), and females emerging from transgenic maize kernels were larger. However, significantly fewer parasitoid females emerged from weevils that developed in transgenic kernels, although parasitoids did not develop more slowly and were not different in size or mass from their conspecifics emerging from hosts in non-transgenic maize kernels.

Conclusion: The emergence of female parasitoids was reduced in transgenic Bt maize, and this effect cannot be explained by the known lepidopteran-specific toxicity of Bt Cry1Ab toxin.

MeSH terms

  • Animals
  • Bacillus thuringiensis Toxins
  • Bacterial Proteins* / analysis
  • Body Size
  • Endotoxins* / analysis
  • Female
  • Food Chain
  • Food Parasitology
  • Fruit / chemistry
  • Hemolysin Proteins* / analysis
  • Herbivory*
  • Host-Parasite Interactions
  • Male
  • Pest Control, Biological
  • Plants, Genetically Modified / chemistry
  • Population Density
  • Sex Ratio
  • Wasps / growth & development*
  • Weevils / growth & development*
  • Weevils / parasitology
  • Zea mays / chemistry
  • Zea mays / genetics*

Substances

  • Bacillus thuringiensis Toxins
  • Bacterial Proteins
  • Endotoxins
  • Hemolysin Proteins
  • insecticidal crystal protein, Bacillus Thuringiensis