Evaluation of Czech hop varieties (Humulus lupulus L.) in a dry area without irrigation

The aim of this study was to determine the difference in performance and variability of selected Czech hop varieties in a dry location without available irrigation. Since 2017, a field experiment has been conducted with 11 Czech hop varieties. The time series of the results helped to show the differences in performance as well as variability between the varieties. The highest yields were achieved by the Uran variety (2.83 t/ha) and Saaz Shine variety (2.76 t/ha), which also exhibited the lowest yield variability, namely 11.17% (Saaz Shine) and 12.53% (Uran), respectively. The lowest hop yield was recorded by the Harmonie variety (1.17 t/ha), which at the same time showed high yield variability (30.92%). The Bohemie variety had the highest yield variability of hops at 35.26%. Furthermore, the Gaia (14.66% w/w) and Uran (13.53% w/w) varieties had the highest alpha acid content. Conversely, the Mimosa variety showed the lowest alpha acid content (1.56% w/w) and also the lowest alpha/beta acid ratio (0.29). The Rubin variety reached the highest alpha/beta acid ratio (3.00). The Uran variety exhibited the lowest variability in alpha (6.16%) and beta (6.28%) acid content and in contrast, the Harmonie variety had the highest variability in these parameters (59.02% for alpha acids and 38.18% for beta acids). The Uran and Saaz Shine varieties showed a very good tolerance to dryness in the dry area. Additionally, the Gaia and Saaz Brilliant varieties showed good performance parameters, i.e. yield and hop resins. The hop varieties Vital, Gaia, Saaz Brilliant, and Saaz Shine had the most intense hop aroma, while the Boomerang and Uran varieties had a high intensity of spicy aroma. The Uran and Saaz Shine are highly resistant to drought.