Jerusalem artichoke (Helianthus tuberosus L.) productivity in different Italian growing areas: a modelling approach

Jerusalem artichoke is considered one of the more interesting crops for inulin production. It has been used to date for the production of low calorie sweetening syrups, dietetic food enriched with fibre, medicines and cosmetics, while more recently, interesting prospects have been opening up for energy uses. The main aspects influencing its adaptability to different pedo-climatic conditions and cropping systems were analysed by implementing CSS (Cropping System Simulator, a simulation model describing crop biomass production) for this specific crop. Growth analysis experimental data of plant dry matter accumulation, obtained over two years of trials (1999-2000) in different Italian growing areas (Udine, Bologna, Bari) under irrigated and rain-fed conditions, were used for the parameterisation and calibration of the model. The biomass accumulation observed and simulated under rain-fed and irrigated conditions in the different growing areas is reported for the different plant organs, with good correspondence shown between simulated and measured values as reported by the statistical indices for the model calibration, particularly for biomass of tubers and leaves. The model studied, despite a simplified description of some processes, proves to represent the maximum biomass yield of Jerusalem artichoke satisfactorily, with an adequate response to the main environmental factors causing yield and biomass production variation among the years and locations. However, further model improvements are necessary in order to better represent the relationship between phenology and translocation of the assimilates between stalk and tuber during the development phases of the plant, suggesting shorter survey intervals over this growing phase.