Not just wheat, but other food grains and fruit crops have an inadequately appreciated profusion of varieties that are endangered or already lost due to modern agricultural practices. Apples, in particular, have many hundreds of types with unique traits and tastes.
There are (or used to be) at least 2000 apple varieties in the US, but of course there could well have been multiple names for the same variety and there, probably no DNA analysis.
The number of tomato varieties used to be estimated at 5000, but the generations are shorter, so they probably have been a lot more than that, coming and going.
Years ago, the germ plasm storage facility that at least used to be in Iowa I think was selecting stuff to germinate to keep the stored seeds viable, and found an overlooked seed packet from the second half of the 19th century, a long-gone seed company’s tomato variety. The germination rate was enormous, and the folks at the lab estimated that it would take at least 250 years in storage for the germination rate of that variety to fall below 50%.