Rust, smut, and wilt can all be caused by fungi in wheat.
Rust:
This is a group of fungal diseases affecting wheat caused by various species of Puccinia. Smut:
This is also a fungal disease in wheat, specifically caused by fungi like Ustilago. Wilt:
While some wilts are caused by bacteria or viruses, certain types of wilt in wheat can be caused by fungi. For example, Cephalosporium stripe is a fungal wilt disease affecting wheat.