Except that the rust fungus isn't the only thing driving up wheat prices. Other factors include a massive drought in Australia, and replanting of wheat fields into corn fields owing to the dramatically increased demand for corn as cattle feed, as well as for biofuels.

The corn-related factors can be significantly reduced by people accepting limits on how much they can drive, and how much beef they can eat. Another thing that we ought to look at cutting back on is feeding grains to ruminants, instead of just grazing them on lands that we'd have no hope of extracting significant amounts of food energy from otherwise. I mean you're sure as hell not going to grow wheat or corn on the canadian shield, but ruminants flourish in that environment nonetheless.