Garlic Harvest...

My garlic has been going great guns until recently when it developed quite severe rust. 

I have now dug them up for drying and storage and are all sound, however 5-6 bulbs have roots that are covered in a white fungus (it looks like dew on tiny white threads).  Coincidentally, these plants all had an ants nest under them.  The bulbs seem fine (if a little damp) although they are smallish compared to the rest.

What is this and should they be destroyed in case they affect the rest in storage.

(These are Solent White planted in Feb, on ground uncultivated for several years)