World Journal of Microbiology and Biotechnology

, Volume 21, Issue 6–7, pp 1279–1284 | Cite as

Changes of Bt Toxin in the Rhizosphere of Transgenic Bt Cotton and its Influence on Soil Functional Bacteria

  • Yu-Kui Rui
  • Guo-Xiang Yi
  • Jing Zhao
  • Bao-Min WangEmail author
  • Zhao-Hu Li
  • Zhi-Xi Zhai
  • Zhong-Pei He
  • Qing X. Li


The concentrations of Bacillus thuringensis (Bt) toxin released from root exudation of Bt cotton were measured by an enzyme-linked immunosorbent assay (ELISA), and its impacts on the numbers of culturable functional bacteria in the rhizosphere were determined by cultivation. No Bt toxin was found in the rhizosphere of non-Bt cotton (SHIYUAN321), but varying levels of Bt toxin were present in the rhizosphere of two Bt cotton varieties (NuCOTN99B and SGK321) during the entire growth period. The levels of Bt toxin in the rhizosphere of NuCOTN99B were significantly higher (p<0.05) than those of SGK321 within all sampling dates except on June 17th in the whole growth season. Significant differences (p<0.05) were found in the numbers of the three functional bacteria between SHIYUAN321 and NuCOTN99B within each sampling day from May 27th to October 27th. No significant differences were found in the numbers of functional bacteria among three cultivars after growth season. Fortification of pure Bt toxin into rhizospheric soil did not result in significant changes in the numbers of culturable functional bacteria, except the nitrogen-fixing bacteria when the concentration of Bt toxin was higher than 500 ng/g. The results indicated that Bt toxin was not the direct factor causing decrease of the numbers of bacteria in the rhizosphere, and other factors may be involved.


Bt cotton Bt toxin functional bacteria rhizosphere 


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. Angle, J.S. 1994Release of transgenic plants: biodiversity and population-level considerationsMolecular Ecology34550Google Scholar
  2. Crecchio, C., Stotzky, G. 1998Insecticidal activity and biodegradation of the toxin from Bacillus thuringensis subsp. kurstaki bound to humic acids from soilSoil Biology and Biochemistry30463470Google Scholar
  3. Cui, J.-J., Xia, J.-Y. 1999Studies on the resistance dynamic of the Bt transgenic cotton on cotton bollwormActa Gossypii Sinica11141146Google Scholar
  4. Darrah, P.R. 1991Models of the rhizosphere A quasi three-dimensional simulation of the microbial population dynamics around a growing root releasing soluble exudatesPlant and Soil138147158CrossRefGoogle Scholar
  5. Donegan, K.K., Palm, C.J., Fieland, V.J. 1995Changes in levels, species, and DNA fingerprints of soil microorganism associated with cotton expressing the Bacillus thuringiensis var. kurstaki endotoxinApplied Soil Ecology2111124CrossRefGoogle Scholar
  6. Donegan, K.K., Schaller, D.L., Stone, J.K., Ganio, L.M., Reed, G., Hamm, P.B., Seidler, R.J. 1996Microbial population, fungi species diversity and plant pathogen levels in field plots of potato plants expressing the Bacillus thuringensis var. tenbrionls endotoxinTransgenic Research52535CrossRefGoogle Scholar
  7. Hails, R.S. 2000Genetically modified plants – the debate continuesTrends in Ecology and Evolution151418CrossRefGoogle Scholar
  8. Hilbeck, A., Moar, W.J., Pusztai-Carey, M., Filippini, A., Bigler, F. 1998Toxicity of Bacillus thuringensis Cry1Ab toxin to the predator Chrysoperla carneaEnvironmental Entomology2712551263Google Scholar
  9. Institute of Soil Science, the Chinese Academy of Sciences1985Research Methods of MicroorganismsScience PressBeijing5051Google Scholar
  10. Jepson, P.C., Croft, B.A., Pratt, G.E. 1994Test Systems to Determine the Ecological Risks Posed by Toxin Release from Bacillus thuringiensis Genes in Crop PlantsMolecular Ecology38189Google Scholar
  11. Lange, P. 1990The German Experience Gained with Field Testing of Genetically Modified PlantsFederal Ministry for Research and TechnologyBonn, GermanyGoogle Scholar
  12. Lin, Q.-M., Zhao, X.-R., Sun, Y.-X., Yao, J. 2000Community characters of coil phosphobacteria in four ecosystemsSoil and Environmental Sciences93437Google Scholar
  13. Losey, J.E., Rayor, L.S., Carter, M.E. 1999Transgenic pollen harms monarch larvaeNature399214CrossRefGoogle Scholar
  14. Maloney, P.E., Vanbruggen, A.H.C., Hu, S. 1997Bacterial community structure in relation to the carbon environments in lettuce and tomato rhizospheres and in bulk soilMicrobiology and Ecology34109117Google Scholar
  15. National Research Council2000Genetically Modified Pest-Protected Plants: Science and RegulationNational Academy PressWashington, DC ISBN 0309069300Google Scholar
  16. National Research Council2002Genetically Modified Pest-Protected Plants: Science and RegulationNational Academy PressWashington, DCGoogle Scholar
  17. Raghu, K., Macrae, I.C. 1966Occurrence of phosphate-dissolving micro-organisms in the rhizosphere of rice plants and in submerged soilsJournal of Applied Bacteriology29582586Google Scholar
  18. Rengel, Z., Ross, G., Hirsch, P. 1998Plant genotype micronutrient status influence colonization of wheat roots by soil bacteriaJournal of Plant Nutrition2199113CrossRefGoogle Scholar
  19. Schenck, N.G. 1976Microorganisms and Root Development and FunctionSoil and Crop Science SocietyMadison, FLGoogle Scholar
  20. Saxena, D., Stotzky, G. 2000Insecticidal toxin from Bacillus thuringiensis is released from roots of transgenic Bt corn in vitro and in situFEMS Microbiology Ecology333539CrossRefGoogle Scholar
  21. Saxena, D., Stotzky, G. 2001Bacillus thuringiensis (Bt) toxin released from root exudates and biomass of Bt corn has no apparent effect on earthworms, nematodes, protozoa, bacteria, and fungi in soilSoil Biology and Biochemistry3312251230CrossRefGoogle Scholar
  22. Saxena, D., Flores, S., Stotzky, G. 1999Insecticidal toxin in root exudates from Bt cornNature402480Google Scholar
  23. Saxena, D., Flores, S., Stotzky, G. 2002Bt toxin is released in root exudates from 12 transgenic corn hybrids representing three transformation eventsSoil Biology and Biochemistry34133137Google Scholar
  24. Sims, S.R., Ream, J.E. 1997Soil inactivation of the insecticidal protein within transgenic cotton tissue: laboratory microcosms and field studiesJournal of Agricultural and Food Chemistry4515021505CrossRefGoogle Scholar
  25. Snow, A., Palma, P.M. 1997Commercialization of transgenic plants: potential ecological risksBioScience478696Google Scholar
  26. Stotzky, G. 2000Persistence and biological activity in soil of insecticidal proteins from Bacillius thuringiensis and of bacterial DNA bound on clay and humic acidsJournal of Environmental Quality29691705CrossRefGoogle Scholar
  27. Tabashnik, B.E. 1994Evolution of resistance to Bacillus thuringiensisAnnual Review of Entomology394749CrossRefGoogle Scholar
  28. Tapp, L., Calamai, L., Stotzky, G. 1994Adsorption and binding of the insecticidal proteins from Bacillus thuringiensis subsp. kurstaki and subsp. tenebrionis on clay mineralsSoil Biology and Biochemistry26663679CrossRefGoogle Scholar
  29. Tapp, L., Calamai, L., Stotzky, G. 1995Insecticidal activity of the toxins from Bacillus thuringiensis subspecies kurstaki and tenebrionis adsorbed and bound on pure and soil claysApplied and Environmental Microbiology6117861790Google Scholar
  30. Wang, B.M., He, Z.P., Zhao, J.X. 1998Study on Bt toxin ELISA for transgenic plantActa Gossypii Sinica102730Google Scholar
  31. Watrud, L.S., Seidler R.J., Huang-P.M., Adriano D.C., Logan T.J. & Checkai-R.T. 1998. Nontarget ecological effects of plant, microbial and chemical introductions to terrestrial system. In Soil Chemistry and Ecosystem Health. pp. 313–340. Madison, Wisconsin: Soil Science Society of America. Special Publication, 52. ISBN 0891188304Google Scholar
  32. Xie, G.-H., Su, B.-L., Cui, Z.-J. 1998Isolation and identification of N2-fixing strains of Bacillus in rice rhizosphere of the Yangtze River valleyActa Microbiologica Sinica38480483Google Scholar
  33. Zwahlen, C., Hilbeck, A., Gugerli, P., Nentwig, W. 2003Degradation of the Cry1Ab protein within transgenic Bacillus thuringiensis corn tissue in the fieldMolecular Ecology12765775Google Scholar

Copyright information

© Springer 2005

Authors and Affiliations

  • Yu-Kui Rui
    • 1
    • 2
  • Guo-Xiang Yi
    • 1
  • Jing Zhao
    • 1
  • Bao-Min Wang
    • 1
    • 3
    Email author
  • Zhao-Hu Li
    • 1
  • Zhi-Xi Zhai
    • 1
  • Zhong-Pei He
    • 1
  • Qing X. Li
    • 4
  1. 1.College of Agronomy and BiotechnologyChina Agricultural UniversityBeijingP.R. China
  2. 2.Laboratory of Food BiotechnologyChina Agricultural UniversityBeijingP.R. China
  3. 3.State Key Laboratory of Physiology and BiochemistryChina Agricultural UniversityBeijingP.R. China
  4. 4.Department of Molecular Biosciences and BioengineeringUniversity of HawaiiHonoluluUSA

Personalised recommendations