Impact of Environmental Factors, Farming Practices, and Genetic Diversity on Hop (Humulus lupulus L.) Yield and Quality

This study explores how extreme heat, farm design, and genotype interact to shape the growth, yield, and quality of hops (Humulus lupulus L.) in semi-arid Mediterranean environments, supporting climate-resilient expansion of high-value specialty crops beyond traditional production regions. Field performance of Cascade and Chinook was evaluated across contrasting management settings in inland Sicily during the 2023 growing season. Microclimatic observations from the Sicilian Agrometeorological Information Service (SIAS) were coupled with the quantitative heat-stress indicator Extra Degree Days (EDD) to link thermal exposure to phenology and quality outcomes. Results suggest that hop performance under semi-arid Mediterranean conditions is shaped by cultivar choice and management-defined environments, with cone yield and, especially, resin and essential oil traits varying across trellis and soil cover settings. Using phase-specific heat exposure as an interpretable indicator of thermal pressure, this study provides a decision-oriented framework to relate heat conditions to phenology and quality outcomes and to support the selection of cultivar–management combinations suited to heat-prone regions. Overall, the findings inform climate-smart hop management strategies to sustain cone quality amid increasing temperature variability in semi-arid environments.