Heard of stem rust? You should

It's not just superbugs (bacteria) resisting antibiotics that can threated the health and welfare of humanity, it's previously defeated scourges of agriculture.  Stem rust is one of the most virulent killers of wheat - a staple of human existinence.  Wheat was bred to resist the worst stem rusts in the 1950s, an effort that won the lead researcher, Norman Borlaug, a Nobel Prize. 

Unfortunately, stem rust is resurgent and the re-engineeerd variety of wheat is no longer resistant.  The rust has serious implications, with a potential to reduce world wheat harvests by 10 percent.

The looming catastrophe can be avoided if the world’s wheat scientists pull together to develop a new generation of stem-rust-resistant varieties of wheat. But scientists must quickly turn their attention to replacing almost all of the commercial wheat grown in the world today.

This is similar to the threat to bananas, where the only variety shipped around the world could be ruined by a leaf fungus.