Soil-less indoor-grown lettuce (Lactuca sativa L.): Approaching the modelling task

Process-based modelling approaches developed for field crops were adapted to address the behaviour of indoor-grown soil-less lettuce under alternative growth conditions. The equations for crop growth and development were simplified to common and consistent terms, re-designed against the peculiarities of a controlled environment and implemented into an easy-to-use, management-oriented, software tool. An array of experiments, where lettuce was grown in growth chambers under water- and nutrient-unlimited conditions, at various temperature and radiation levels, was performed to build a data set to evaluate the model. Critical parameters and suitable relationships were identified and evaluated for possible use in management-oriented applications. Summary statistics of the evaluation indicated a satisfactory description of crop growth (EF > 0.50) and development (±1 day discrepancy). As a result, there is a potential for the present approach to be applied to soil-less lettuce systems under alternative management options.