PIEteR: a field specific production model for sugar beet growing.

PIEteR is a field-specific production model for sugar-beet growing. It can provide quantitative information about the technical, economic and environmental consequences of plant density, nitrogen application and harvest date. Its core is a growth model that simulates rates of emergence, development, and root and sugar production, corrected for non-optimal water availability. Although PIEteR is not yet able to simulate extreme situations correctly, it is a good basis for the further development of a decision-support system.