Evaluation of original historical clones of hops (Humulus lupulus L.)

Abstract

The aim of this study was to compare yield and technological parameters of Czech historical hop clones, which were grown in our current climatic conditions. The highest yields from the selected original hop clones were found in “Úštěcký smetaňák” (1.93 t/ha), “Dubský zeleňák” (1.80 t/ha) and “Hřebčí chmel” (1.51 t/ha), which is probably caused by a genetic difference from Saazer hop. On the contrary, a low yield of hops was recorded in “Mastýřovický” (0.50 t/ha). In terms of brewing parameters, the highest contents of valuable alpha acids were detected in Osvald’s clones no. 147 a/I (3.88% w/w), no. 86 (3.71% w/w) together with no. 114 (3.45% w/w), while the lowest level (1.05% w/w) was found in “Hřebčí chmel” and “Úštěcký smetaňák”. The highest contents of essential oils were measured in Osvald’s clone no. 147 a/I (0.77% w/w), “Žatecká populace” (0.68% w/w) and Osvald’s clone no. 126 (0.65% w/w). Vice versa, the clones “Mastýřovický” (0.35% w/w), “Hřebčí chmel” (0.35% w/w) and “Tršický” (0.31% w/w.) exhibited the lowest contents. The evaluated hops displayed a relatively balanced composition of essential oils with the exception of “Dubský zeleňák”, which has an extremely low ratio of farnesene (4.35% rel.), but also a high ratio of selinene (8.95% rel.). Osvald’s clone no. 124b and 126 is genetically identical with the variety of Fuggle. The results show that clones “Hřebčí chmel”, “Úštěcký smetaňák” and “Dubský zeleňák” are different from other clones.

Essential oils in Czech hop varieties

“…The clonal selection concentrated on fine aroma hops, with a preference being given to the fine hoppy aroma. The results of recent chemical and genetic analyses of these clones show that they are very similar to the currently grown Osvald clones 31, 72 and 114 (Nesvadba et al, 2020a). In the 1960s, hybridisation was introduced to hop breeding, resulting in the registration of the Bor, Sládek and Premiant hop varieties in the 1990s.…”

“…Hop varieties are characterized by yield, resistance to disease and pests, sensitivity to agrotechnological interventions as well as by the content and composition of hop resins and HEOs (Nesvadba et al, 2020a). The performance of hop varieties depends on these characteristics.…”

Two fingerprinting sets for Humulus lupulus based on KASP and microsatellite markers

“…Hop has benefited from the sequencing revolution, enabling access to thousands of SSR sequences, including long-core repeat motifs exceeding two bases [5,7,19,[30][31][32]42,80,82]. Initially, dinucleotide-containing SSRs were used in plants because of their relative abundance and polymorphism when compared to SSRs with longer repeat motifs [84]. However, they were found to suffer from stuttering, split peaks, and binning errors [24,85,86].…”

“…'Early bird' (aka 'Early bird Golding') has already been established as a Golding clone of the original 'Golding' selected in 1790[17]. Osvald Saazer Clone 1267 is most likely Osvald Clone 126, a known Fuggle-type selected by Dr. Karel Osvald during his work from 1927 to 1948[84]. 'Wuerttemberger', should be the original 'Wuerttemberger', a Serbian style hop accession.…”

Drought-tolerant hop genotypes – A promising solution to the problem of climate change for the hop industry?

“…Currently, these clones, well-known as Saaz variety, are still grown on 90% of the total area on which hops are grown in the Czech Republic. The variety Saaz has a fine aroma with a typical pure hop aroma and herbal and floral background that ensures excellent taste of traditional Pilsner Lager (Nesvadba et al, 2020).…”