Rust on Supai Red Parching Corn

After reading about parching corn, we went with one of Carol Deppe's suggested varieties, Supai Red which we purchased from Seeds of Change. It got off to a rough start with the largest population of slugs we've ever seen and the leaves looked like they had been put through a paper shredder. After many applications of wood ash with a Dustin' Mizer (at dawn and dusk), the plants finally began to outgrow the slugs when they got over 1' tall and were looking great until about a couple of weeks ago. When they started to tassel, rust set in and the plants look quite dismal at this stage. Photosynthesis has been severely compromised. I'm wondering if anyone has any experience with this disease? Can the plants still make mature ears? After the slugs this spring, the weather has continued to be hot, humid, and rainy. We've never had this disease before in over 30 years of gardening in the upper Midwest and are curious if this is just the year or if this variety is susceptible.  Anyone else successfully growing this variety in the upper Midwest?

I can't speak to the problem of rust, except to say I hope it turns out alright.

If there are fungus-friendly conditions as the corn is tasseling, you might get a good crop of huitlacoche...which is tasty, but doesn't keep well at all, so would defeat the purpose of growing a parching corn variety.