Are simulation models ready for agricultural research in developing countries?

As an example of the application of simulation modeling in developing countries, the SARP (Simulation and Systems Analysis for Rice Production) project is reviewed. SARP promoted the ORYZA models for paddy rice (Oryza sativa L.) research in Southeast Asia. The models successfully simulated crop growth as affected by canopy photosynthesis, sink capacity, and N nutrition. The rather crude plant physiology in these and similar models limits their usefulness in simulating the effect of morphological modifications and the response to various stress factors. Modeling skills developed by SARP in Asian research institutes cannot be maintained,without continued coordination from advanced institutes. More basic knowledge on the plant's morphogenesis and feedback mechanisms is required for effective simulation of plant adaptation to complex growth environments, including intercropping, as found in many developing countries. A more rigorous modular approach to modeling is advocated, as well as standardization of modules for well-understood processes, as part of a toolkit for applied research for use in combination with other techniques, including statistical techniques.