Andreote Fernando Dini, Gullo Marcelo José Mortatti, de Souza Lima André Oliveira, Júnior Walter Maccheroni, Azevedo João Lúcio, Araújo Welington Luiz
Escola Superior de Agricultura "Luiz de Queiroz"-USP-Departamento de Genética Laboratório de Genética de Microrganismos, Piracicaba-SP, Brazil.
J Microbiol. 2004 Sep;42(3):169-73.
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.
阴沟肠杆菌（菌株PR2/7）是一种柑橘类植物中的基因改造内生菌（GME），携带不同质粒（pEC3.0/18、pCelE、pEglA和pGFP），在温室条件下接种到脐橙幼苗中。通过对2个不同形态学组的分析，研究了其对本地细菌内生群落的影响。在温室中评估接种种子的发芽率以及体外条件下的质粒稳定性。结果表明，在不同处理中，植物体内存在丰富多样的内生群落，且一些细菌类群在组织定殖方面具有特异性。各处理间观察到种子发芽率的变化：总体而言，与携带pEC3.0/18克隆的PR2/7相比，携带pEglA的PR2/7细菌克隆显著降低了种子发芽率。这表明pEglA质粒的存在改变了细菌与种子的相互作用。柑橘幼苗的内生群落因处理方式而异。在用携带pEglA克隆的PR2/7处理的幼苗中，在整个内生群落背景下，第二组的种群数量显著减少。这些结果表明，基因改造内生菌的应用会导致柑橘幼苗内生细菌群落发生变化。
