In each crop you would have different objectives, but a major objective in any breeding program is yield, that is, increasing the productivity from a certain area with certain inputs. That's the minimum requirement and it's usually coupled with requirements for quality, whether they have to do with disease on the produce or the addition of compounds like vitamins and antioxidants. Increasingly, we're being asked to look at the way it affects us in our nutrition and our health.
On October 25th, 2011. See this statement in context.