Shallots... I give up!

Have been watching my shallots growing with pride for the last six weeks or more , a healthier looking lot you could not wish to see! This week the are starting to keel over I have lifted the ones that are dying and there is a really horrible sour smell from the bulbs which have gone soft. I suspect it is white rot. What is really odd that in the same bed and some actually growing between them are onions which are completely healthy but at an earlier stage in their growth , most of the shallots had already produced a decent sized bulb. In desperation I have sprayed the ones that have not keeled over yet with BM around the bulbs just in case it is some sort of mildew that is affecting them.
I think I am going to give shallots a miss for a while ... although I grow onions without too much hassle in fact I am just using the last of the ones I lifted in August last year don't have problems with leeks or garlic either??

If you grew the shallots from bought in bulbs they may have had basal root spores on, not good for future onion crops Keep an eye on the other alliums, if they're in the same bed.

Yes Mum it is a problem when you buy certified products you just have to hope. I am now wondering if they in fact have a bout of downy mildew. I see speckles on the foliage which does look like it could be that . We have just gone from a hot dry spell to a really quite cold damp period and this has definitely had some sort of effect on the plants. If it was white rot would they all suddenly keel over? As you as about the other onions right next to the shallots ... they are going great right now no problems at all at the moment??

Any chance you can blitz them with a strong dilute feed, either organic or chemical?

I found all this happened to all sorts of garlic here, and after a squirt of all sorts of home-made liquid poo stuff, eventually got some sort of result...

Tricky one really!

I think I may just have stumbled across thrips! When I lifted the affected bulbs I saw a lot of very small white wriggling larva around the base of the bulbs could it be these creatures?
http://www.aafarmer.co.uk/wp-content/uploads/2018/02/Thrips.jpg

Thrips, or Allium leaf miner, which seems a bit more common here, anyway?

The sour smell is quite distinctive, had the same problem one very wet Summer, and even those bulbs that seemed okay soon went off in storage. It affected all the newer varieties that I was growing  - Longor, Golden Gourmet, Red Sun - however an older variety that I've had for many years was fine, so I just grow that now.