Beating the heat is one of the goals most vigorously pursued by plant geneticists. A solution is not yet in sight, but after so many years of research, it is clear that there are several avenues worth exploring. The three most important things are testing, testing, testing.
The first consideration is that plants can adopt different strategies to survive when water is scarce. You can distinguish between drought resistance and water use efficiency, or go subtle by talking about drought avoidance, drought escape, and drought tolerance.
Another basic premise is that drought can vary in intensity and duration, so that a plant capable of tolerating moderate stress may still succumb under more extreme conditions. Further complicating matters is the fact that, to be adopted by farmers, future crops will have to prove not only more resilient but also as productive as the varieties they are intended to replace. Two strategies are being pursued at the University of Milan with the help of CRISPR.