Calibration and validation of WOFOST model for seven potato (Solanum tuberosum) cultivars in India

A crop-growth simulation model WOFOST was calibrated and validated for 7 Indian potato (Solanum tuberosum L.) cultivars, namely ‘Kufri Arun’, ‘Kufri Garima’, ‘Kufri Khyati’, ‘Kufri Kanchan’, ‘Kufri Lalit’, ‘Kufri Sadabahar’ and ‘Kufri Surya’. The time course data on crop growth and development collected from field experi-ments at Modipuram (Meerut), Patna, Gwalior and Jalandhar during 2011–12 to 2014–15 were used for calibration and validation of model. The model was calibrated and validated for Indian potato cultivars with reasonable accuracy. Simulated values for emergence and initiation of tuber growth varied between 1 and 5 and 3 and 5 days, respectively, from the measured values, for different cultivars. Variation in final dry-matter yield was maximum in ‘Kufri Surya’ (7.5%), while the variation in tuber dry-matter yield at maturity was maximum in ‘Kufri Arun’ (6.9%), which were within the acceptable limits. The indicators of model performance, i.e. the maximum error (ME), root mean square error (RMSE), coefficient of residual mass (CRM) and coefficient of determination (CD) also indicated that the model performance was very satisfactory. The results demonstrated that the WOFOST model can be used for studying and predicting the growth and development of potato crop under Indian situation for popular Indian cultivar.