This review addresses the possible ecological effects of transgenic plants
on micro-organisms in the field, hence, in the phytosphere and in the soil
matrix. The important steps involved in the interaction between plant DNA
and bacteria and the factors that influence the horizontal gene transfer
(HGT) process will be discussed. HGT is a process in which two partners are
involved, even if indirectly. In the first section, aspects concerning
bacteria, such as their physico-chemical, biological and genetic
characteristics, are described. Parameters affecting transgenic DNA fate in
the environment are described in the second section. Subsequently,
terrestrial habitats are evaluated in terms of their capacity to favor
horizontal gene transfer. Finally, we focused on several studies in order to
evaluate possible perturbations of soil bacterial community composition due
to cultivation of transgenic plants in the field.