Dave Wood says lets not rush into breeding for climate change:
There are three distinct existing resources we can tap.
The first is the ability of crops to thrive after long-distance introduction. …
The second resource is the really vast data base from up to 50 years of multi-locational trials carried out as a matter of course by CGIAR institutes. …
The third resource is climate-matching. …
You need to read his examples. And when you have, you may find you agree. Or not.