In 2003, during a 5-year study of crop disease, the first alarm was raised that wheat appeared to be worse affected by 'fusarium head blight' in fields where glyphosate herbicide had been applied just before planting. Laboratory studies at the time also indicated that fusarium grows faster when glyphosate-based weedkillers are added to the medium they're growing in.
Fusarium head blight is a devastating fungal disease which destroys a fifth of wheat harvests in Europe alone. This fungus produces 'mycotoxins' (poisons) known to cause cancer of the liver and kidney, disorders of the blood and lung, vomiting, and damage to the immune system. Anything which promotes fusarium is a serious business.