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General Information

Document type
  • Peer-reviewed journal article
GE organism
  • maize
GE trait
  • insect resistance
  • USA


Safety for environment
  • negative effect

Transgenic pollen harms monarch larvae

Losey, JE; Rayor, LS; Carter, ME
Nature. 1999 May. 399(6733):214

Link to full text (journal may charge for access)

PMID: 10353241 DOI: 10.1038/20338 ISSN: 1476-4687


Although plants transformed with genetic material from the bacterium Bacillus thuringiensis (Bt ) are generally thought to have negligible impact on non-target organisms1, Bt corn plants might represent a risk because most hybrids express the Bt toxin in pollen2, and corn pollen is dispersed over at least 60 metres by wind3. Corn pollen is deposited on other plants near corn fields and can be ingested by the non-target organisms that consume these plants. In a laboratory assay we found that larvae of the monarch butterfly, Danaus plexippus, reared on milkweed leaves dusted with pollen from Bt corn, ate less, grew more slowly and suffered higher mortality than larvae reared on leaves dusted with untransformed corn pollen or on leaves without pollen.


Bt, corn, Danaus plexippu, Monarch butterfly


Funding source
  • Not reported
Funding country
  • Not reported
Funding type
  • Not reported

Publication history


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Cite this study


Losey, JE, LS Rayor, ME Carter. "Transgenic pollen harms monarch larvae." Nature 399.6733 (1999): 214. Web. 7 Dec. 2023.


Losey, JE., Rayor, LS., & Carter, ME. (1999). Transgenic pollen harms monarch larvae. Nature, 399(6733), 214. doi:10.1038/20338

Please verify citations before use, citations are automatically generated based on information stored within the GENERA database and therefore may or may not be correct.