There is considerable current interest regarding glyphosate effects on GR soybeans; however, little information is available on the performance of GR2 soybean beyond commercial and farmer testimonial statements. Based on previous controlled and field studies with GR1 soybean,we hypothesize that glyphosate released from roots may affect microbial populations and ⁄ or activity in the rhizosphere, regardless of transgenic soybean generation.Confounding the accurate assessment of glyphosate impacts on plant-microbial interactions are the multiple rates of glyphosate employed during the growing season that are often different depending on the global production region and the soybean growth stage when the herbicide is applied. Therefore, the objective of this study was to evaluate selected rhizosphere microbial communities in GR1 and GR2 soybeans receiving variable rates of glyphosate applied at different growth stages.