title: Subacute effects of transgenic crylab bacillus thuringiensis corn litter on the isopods Trachelipus rathkii and armadillidium nasatum.
abstract: Laboratory studies were conducted to investigate the subacute effects of transgenic Cry1Ab corn leaf material containing Bacillus thuringiensis (Bt) protein on the terrestrial isopods Trachelipus rathkii and Armadillidium nasatum. Survival and growth were measured for eight weeks in isopods fed leaf material of two Bt11 corn varieties, two Monsanto 810 (Mon810) corn varieties, and the isolines of each. Total lipid and protein content of the organisms was measured to examine effects on energetic reserves. Armadillidium nasatum individuals in all treatments responded similarly. For T. rathkii, no statistically significant effect of Bt was observed, but statistical differences were observed in growth between hybrids. Protein and sugar content of the food were found to be correlated with the differences in growth for T. rathkii. Total protein content was higher in T. rathkii and A. nasatum fed material with higher protein and sugar content. A trend toward less growth in T. rathkii on Bt corn varieties versus their isolines triggered a concentration-response assay with purified Cry1Ab protein. No adverse effects of purified Bt protein were observed. These results indicate that little hazard to T. rathkii and A. nasatum from Bt corn leaf material from these hybrids exists. However, nutritional differences in corn hybrids contributed to differences in isopod growth.
authors.affiliation: Department of Entomology and Interdepartmental Toxicology Program, Iowa State University, 115 Insectary, Ames, Iowa 50011, USA.
authors.forename: Bryan W
authors.initials: BW
authors.lastname: Clark
authors.forename: Kelsey R
authors.initials: KR
authors.lastname: Prihoda
authors.forename: Joel R
authors.initials: JR
authors.lastname: Coats
mesh_terms: D000818:Animals; D001413:Bacillus thuringiensis / Q000737:chemistry*; D000083722:Bacillus thuringiensis Toxins; D001426:Bacterial Proteins / Q000633:toxicity*; D001427:Bacterial Toxins / Q000633:toxicity*; D004731:Endotoxins / Q000633:toxicity*; D004797:Enzyme-Linked Immunosorbent Assay; D006460:Hemolysin Proteins / Q000633:toxicity*; D007313:Insecta / Q000187:drug effects* / Q000254:growth & development; D030821:Plants, Genetically Modified
chemical_list: D000083722:Bacillus thuringiensis Toxins; D001426:Bacterial Proteins; D001427:Bacterial Toxins; D004731:Endotoxins; D006460:Hemolysin Proteins; C030956:insecticidal crystal protein, Bacillus Thuringiensis