Food production will have to increase in the next 50 years to meet the demand from a growing population and changed food habits, as e.g. for higher meat consumption. The increased production will have to be based on rain-fed agriculture or more effective irrigation strategies, and will have to be mainly in the tropics, since further enhancement in productivity in the western agriculture is a slow process, if possible at all. Climate change will become a major threat to this demand/supply equation, since many new problems will hamper the productivity gain that otherwise could have been achieved. Simple movement of genetic material or management techniques (North South or South North) to overcome future climate change, are doubtful, since photoperiodic control of most tropical species are very strong. Establishing more local breeding programs in a wider number of tropical species than currently, is highly relevant for continuously adapting to changing climate. Apart from crop breeding, many new research areas within plant physiology needs further work.