Suitability assessment of different hemp (Cannabis sativa L.) varieties to the cultivation environment

Hemp crop is nowadays spreading in many new areas and then the prediction of crop behavior and performance in different specific environments could be of interest. This study presents a methodology to assess hemp suitability to cropping environments by a combined approach of experimental trials and simulation. The experiment of this study involved six hemp varieties, evaluated for dual-purpose production (seed and stem) during two years of trials in North-East Italy. The results were exploited to develop and calibrate a simulation model able to evaluate hemp crop suitability to the trial environment. Yields obtained for hemp biomass and stems were similar to that of other European experiments, while seed production was shown to be slightly lower. Excessive temperature (daily maximum temperatures over 30 °C) during the grain-filling phase would be one of the main factors affecting seed quality, limiting the seed oil accumulation. Parameters already available in the literature and data obtained from the present experiment were used in the modelling approach to estimate phenological parameters, seed production as affected by water stress, and seed oil content as a function of temperature during the grain-filling period. In order to evaluate the hemp crop suitability to the environment, a scenario analysis using historical meteorological data was performed to predict variability - with different irrigation regimes - of seed yield, seed oil content, maturity date and required seasonal irrigation volume, for each variety in the soil and climatic conditions of the trial site.