Answer: Based on your description it sounds like the damage is being caused by thrips possibly exacerbagted by lack of water. I would suggest you work with your county extension to get a specific diagnosis and based on that determine how to proceed -- you may have to treat the corms during the storage period to stop them from overwintering. If it actually is a problem that requires a chemical control, they will be able to tell you what to use and how/when is best to apply it. Good luck with your glads!
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