Risk assessment in decision-making on rainfed cotton

A probability-based methodology to assess the effect of year-to-year climatic variability, soil and management input on crop response is demonstrated using the COTONS (R) - SIMBAD system. The methodology allows for the quantification of the risk associated with these input variability using a systematic and bias-free approach. It also allows the user to identify relevant crop state variables that can be used for short-term better decision making related to crop management. Because of the high cost and time involved in evaluating management practices, these modeling approaches can be effective tools for better decision making. Due to the significance in their results, the authors recommend this risk-based approach as a way to address decision making under site and climatic uncertainties. The COTONS (R) - SIMBAD system is demonstrated as an important research tool for pushing back the limits of classical adaptative research programs. It provides an original tool to analyse the cotton crop response variability which could not have been assessed with classical enquiries or experimental designs. Under rainfed conditions, the climate remains the main determinant of variability in crop response Under a reference crop management sequence. This uncertainty in crop response is simulated by the model and analysed in terms of risk according to yield targets and crop management sequences. The intermediate crop state variables simulated by the model are used for day-to-day decision rules. This pilot research is an important step before evaluating these decision rules under field conditions. These decisions help reduce the risk of underyield a target value and have an economic cost associated which was also presented with these risks.