Gressel (2002) suggests that the transgenic EPSPSin GR1 soybean is considerably less efficient than thewild-type enzyme and produces insufficient amounts ofphytoalexins to prevent fungal infection. Key inducibledefence components associated with the shikimic acidpathway include antimicrobial phytoalexins that accumu-late rapidly at the site of pathogen infection (Johal andHuber 2009). Lignification of cell walls at and around theinfection site also depends on a shikimate-derivedcomponent to fortify cells and ensure isolation of thepathogen at the infection site. Decreased lignin contentmay also be because of the reduced photosynthesis insoybean caused by glyphosate (Zobiole et al. 2010a).Decreased lignification and phytoalexin production allowincreased root colonization by Fusarium in plants dam-aged by glyphosate (Johal and Rahe 1988). Thus, consid-erable concern exists regarding potential detrimentaleffects of rhizosphere micro-organisms on soybean pro-ductivity resulting from either direct effects of glyphosateor indirect effects on plant physiological functions.