The rice planthopper parasitoid Anagrus nilaparvatae is not at risk when feeding on honeydew derived from Bacillus thuringiensis (Bt) rice

Pest Manag Sci. 2018 Aug;74(8):1854-1860. doi: 10.1002/ps.4886. Epub 2018 Mar 25.

Abstract

Background: Honeydew is a sugar-rich excretion produced by sap-feeding Sternorrhyncha and is an important source of carbohydrates for natural enemies, especially for parasitoids. Honeydew derived from genetically modified (GM) crops can contain amounts of the transgene product. Thus, it is a possible route of exposure for natural enemies feeding on honeydew. In the present study, the potential effects of Nilaparvata lugens honeydew derived from Cry1C and Cry2A rice on different life-table parameters and parasitism dynamics of the egg parasitoid Anagrus nilaparvatae were evaluated under laboratory and field conditions. Furthermore, the Bacillus thuringiensis (Bt) levels and the sugar and amino acid composition of honeydew were analyzed.

Results: Results indicated that A. nilaparvatae was exposed to Bt proteins by feeding on N. lugens honeydew produced from Bt rice. However, honeydew derived from the tested Cry1C and Cry2A rice lines did not affect the development, longevity, emergence rate and fecundity of A. nilaparvatae. Also, the parasitism dynamics in the field remained unaffected. In addition, the sugar and amino acid composition of N. lugens honeydew was not significantly altered for the tested Bt rice lines compared with the parental non-Bt plant.

Conclusion: The quality of honeydew derived from the tested Bt rice lines as a food resource for natural enemies was maintained. © 2018 Society of Chemical Industry.

Keywords: Bacillus thuringiensis (Bt) rice; honeydew; natural enemy; non-target effects; risk assessment.

MeSH terms

  • Amino Acids / chemistry
  • Animals
  • Bacillus thuringiensis Toxins
  • Bacterial Proteins / adverse effects*
  • Diet
  • Endotoxins / adverse effects*
  • Hemiptera / parasitology*
  • Hemolysin Proteins / adverse effects*
  • Host-Parasite Interactions*
  • Insecticides / adverse effects*
  • Life Tables
  • Oryza / chemistry*
  • Plants, Genetically Modified / chemistry
  • Sugars / chemistry
  • Wasps / physiology*

Substances

  • Amino Acids
  • Bacillus thuringiensis Toxins
  • Bacterial Proteins
  • Endotoxins
  • Hemolysin Proteins
  • Insecticides
  • Sugars
  • insecticidal crystal protein, Bacillus Thuringiensis