Courtesy of John Sealander, Blue Ribbon Eggs, Franklin, NC
There have always been droughts and floods and storms and hurricanes. When you save your own seed you are naturally and spontaneously breeding to the range of your typical conditions, and as you select over time you are developing -without much effort- produce that will grow best in your area to your unique conditions. Exotic hybrids may work in 'industrial agriculture', but are actually undesirable for small self-sufficient farming. Not enough genetic diversity. And way too fragile, among other short comings.
The Anasazi grew corn in the Arizona Desert 1,000 to 1,500 years ago. 4' tall and 8' apart. Space wasn't the problem, water was. Drought (or disease) may have done them in, but they lasted a loooong time. I am growing corn and beans and squash, some cultivars of which have been grown here for 1,000 years starting with the Cherokee and perhaps their predecessors.
If you want to win in the battle with local conditions start with local heirlooms and open pollinated seed that are common in your area, save your best seed each season and you'll have food most years. Stash a three year supply of the core stuff (staples), and odds are you'll be fine for a lifetime.