Recently, we have received an increased number of emails and phone calls regarding the negative interactions of glyphosate with micronutrients and plant diseases. There is a considerable amount of literature in both scientific and popular press about this topic. Bob Hartzler at Iowa State University has done an excellent literature review and discussion of this topic, which was presented at the 2010 ISUE Integrated Crop Management Conference (Ames, IA). The take-home message of Bob’s article is that although these interactions cannot be completely ruled out because of where they most likely occur (rhizosphere), there is no empirical data to suggest that there is a widespread negative impact.
We welcome your additional questions and comments on this subject.
Paul and Shawn