probably/possibly. some chemicals can leave the roots of plants if in an excessively high concentration. on the other hand used correctly I dont think it will be a problem if used in the concentrations mentioned.

A systemic fungicide, such as 'rose clear' acts on the stems and leaves and not below ground where your mycorrhiza works. If your plants are not looking happy, have you thought you may have vine weevil grubs - they eat roots!! I have come across alot this year, and keep mentioning it to pass the message around.