Inflorescence Yield, Essential Oil Composition and Antioxidant Activity of <i>Cannabis sativa</i> L. cv ‘Futura 75’ in a Multilocation and On-Farm Study

Industrial hemp (<i>Cannabis sativa</i> L.), being a multiharvest crop, can increase farm profitability and cropping system diversification, including in marginal areas. Since inflorescence essential oil (EO) represents a valuable co-product for cosmetics and pharmaceutical sectors, the aim of this study was to assess the effect of pedoclimatic conditions on the inflorescence yield. EO content, composition and antioxidant capacity of the monoecious variety ‘Futura 75’. So, on-farm trials were performed in central Italy at three sites (SL, LA and SPG), which differed in terms of soil (taxonomic classes; chemical and physical characteristics), microclimate conditions (rainfall and air temperatures) and agricultural value. The results highlighted how location specificities significantly influence crop performance. Strong differences in productive parameters were observed among the farms, with inflorescence yields ranging from 1.3 to 4.9 Mg ha⁻¹, mainly depending on the differences between the maximum and minimum air temperatures (ΔT) since negative correlations were found. Similarly, the concentration of monoterpene and sesquiterpene hydrocarbons showed a reduction when ΔT during the studied period was higher; conversely, oxygenated sesquiterpenes showed an increment due to a higher ΔT. Only phenylpropanoids were affected by rainfall, showing a positive correlation. All these findings confirm that in hemp, satisfactory productions can be reached only by matching territorial suitability. The variability in EO’s characteristics suggests, in fact, that the “uniqueness” of the EOs derives from a combination of the pedological, climatic and agronomic variables of each site.