Impact of Genetically Modified Enterobacter cloacae on Indigenous Endophytic Community of Citrus sinensis Seedlings

  • Fernando Dini (Escola Superior de Agricultura 'Luiz de Queiroz'-USP-Departanento de Genetica Laboratorio de Genetica de Microraganismos) ;
  • Mortatti, Marcelo-Jose (Escola Superior de Agricultura 'Luiz de Queiroz'-USP-Departanento de Genetica Laboratorio de Genetica de Microraganismos) ;
  • Souza, Andre-Oliveira de (Universidade do Vale do Itajai, Centro de Ciencias Tecnologicas da Terra e do Mar) ;
  • Walter Maccheroni (Alellyx Applied Genomics) ;
  • Joao Lucio (Escola Superior de Agricultura 'Luiz de Queiroz'-USP-Departanento de Genetica Laboratorio de Genetica de Microraganismos, Universidade de Mogi das Cruzes Nucleo Integrado em Biotecnologia) ;
  • Welington Luiz (Escola Superior de Agricultura 'Luiz de Queiroz'-USP-Departanento de Genetica Laboratorio de Genetica de Microraganismos)
  • Published : 2004.09.01

Abstract

Enterobacter cloacae (strain PR2/7), a genetically modified endophyte(GME) in citrus plants, carrying different plasmids (pEC3.0/18, pCelE, pEglA and pGFP), was inoculated into Citrus sinensis seedlings under greenhouse conditions. The impact of this on the indigenous bacterial endophytic community was studied by analyses of 2 different morphologic groups. The germination rates of inoculated seeds were evaluated in greenhouse, and plasmid stability under in vitro conditions. Results demonstrated a great and diverse endophytic community inside plants, and specialization in tissue colonization by some bacterial groups, in different treatments. Shifts in seed germination rate were observed among treatments: in general, the PR2/7 harboring pEglA bacterial- clone significantly reduced seed germination, compared to the PR2/7 harboring pEC3.0/18 clone. This suggests that the presence of the pEglA plasmid changes bacteria-seed interactions. The endophytic community of citrus seedlings changed according to treatment. In seedlings treated with the PR2/7 with pEglA clone, the population of group II decreased significantly, within the context of the total endophytic community. These results indicate that the application of GMEs induces shifts in the endophytic bacterial community of citrus seedlings.

Keywords

References

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