Evaluating new aromatic hop genotypes

Hop growers request new cultivar should have qualitative parameters of Saaz semi-early red-bine hop with higher yield potential. Therefore currently, there are efforts to breed new aroma cultivars. The aim of diploma thesis was to evaluate and choose new breeding aroma genotypes, which would show equal or better quality and quantity parameters than Saaz semi-early red-bine hop registered cultivar, based on production indicators, chemical and genetic analyses. Obtained data were evaluated by basic statistical characteristics, two-sided t-tests for independent selections and correlation analysis. A yield is the most important quantitative parameter, which is mainly and significantly dependent on climatic conditions. All evaluated genotypes in diploma thesis have reached higher average yields than ŽPČ cultivar, except genotype 4799. Genotype 4801 reached the highest theoretical yield (2.2 tons of dry hops) in year 2014 and genotype 4975 (1.77 tons of dry hops) in year 2015 from achieved results. A content of alpha bitter acids is the most important qualitative parameter. All aroma new breeding lines have shown parameters of fine aroma hops according to chemical analyses of hop resins. Aroma genotype 4975 showed the highest average contents of alpha and beta bitter acids, balanced ratio between alpha and beta bitter acids, the lowest contents of cohumulone and colupulone, and as well it kept a low or middle variability in all studied traits of chemical analyses of hop resins. A relative content of farnesene higher than 12% is a typical for aroma hop cultivars with ŽPČ cultivar origin. All evaluated genotypes achieved this criteria. We evaluated the relationship to Saaz semi-early red-bine hop cultivar based on genetic analyses. Genotype 4799 has been genetically the closest to ŽPČ. Brewed beers have been a same quality as beers from Saaz semi-early red-bine hop cultivar by sensory evaluation

Hop Breeding in the Czech Republic.

Hop breeding objectives in CR can be divided into aroma and bitter hops, both being resistant to stresses, dwarf varieties for cultivation in low trellis and varieties for pharmaceutical utilization. In 2008 we managed to release Vital and Kazbek. Varieties Saaz Late and Bohemie were registered in 2010. Recently we have bred some perspective genotypes with high contents of xanthohumol or desmethylxanthohumol (DMX). In January 2011, we were awarded funding for a new four years EUREKA Project, which is an inter-governmental network that supports the development for innovations across all sectors of industry within EU. It should help us to develop new low trellis high quality aroma hops as sustainable replacements for traditional tall hops in the future.Hop breeding objectives in CR can be divided into aroma and bitter hops, both being resistant to stresses, dwarf varieties for cultivation in low trellis and varieties for pharmaceutical utilization. In 2008 we managed to release Vital and Kazbek. Varieties Saaz Late and Bohemie were registered in 2010. Recently we have bred some perspective genotypes with high contents of xanthohumol or desmethylxanthohumol (DMX). In January 2011, we were awarded funding for a new four years EUREKA Project, which is an inter-governmental network that supports the development for innovations across all sectors of industry within EU. It should help us to develop new low trellis high quality aroma hops as sustainable replacements for traditional tall hops in the future

Brewing characteristics of Czech fine aroma hops "Saaz".

Since 1998 we have been carrying out brewing tests with Saaz, known worldwide as the high quality standard within the group of fine aroma hops. Its brewing characteristics are compared to the other Czech as well as foreign aroma varieties (Tettnang, Spalt, Lublin, Hersbruck and Strieselspalt). Excellent quality of Saaz was confirmed in brewing tests. Optimal time for hopping with Saaz is ten minutes before the end of boiling in the third hopping. Saaz Late, a new Czech aroma variety was released in 2010. This variety shows similar brewing characteristics to Saaz.Since 1998 we have been carrying out brewing tests with Saaz, known worldwide as the high quality standard within the group of fine aroma hops. Its brewing characteristics are compared to the other Czech as well as foreign aroma varieties (Tettnang, Spalt, Lublin, Hersbruck and Strieselspalt). Excellent quality of Saaz was confirmed in brewing tests. Optimal time for hopping with Saaz is ten minutes before the end of boiling in the third hopping. Saaz Late, a new Czech aroma variety was released in 2010. This variety shows similar brewing characteristics to Saaz

Characterization and identification of Vital variety

Vital je nová a první česká odrůda, která má význam jak pro pivovarnictví, tak i pro farmacii. Je výsledkem šlechtění chmele pro farmaceutické a biomedicinální účely. Charakterizace a identifikace byly provedeny jak v čerstvém stavu v průběhu růstu chmele, tak i po usušení chmelových hlávek. Na základě morfologických popisů je stanovena identifikace na podrobných rozborech révy, listů, pazochů a hlávek. DNA analýzy byly provedeny z mladých listů, a to metodami STS a SSR. Pro identifikaci suchých hlávek byly použity podrobné mechanické rozbory a chemické analýzy. Z chemických analýz byly získány chmelové pryskyřice, polyfenoly a silice. Získaná statistická data a jejich variabilita charakterizují odrůdu Vital

The Influence of <i>Hop Latent Viroid</i> (HLVd) Infection on Gene Expression and Secondary Metabolite Contents in Hop (<i>Humulus lupulus</i> L.) Glandular Trichomes

Viroids are small infectious pathogens, composed of a short single-stranded circular RNA. Hop (Humulus lupulus L.) plants are hosts to four viroids from the family Pospiviroidae. Hop latent viroid (HLVd) is spread worldwide in all hop-growing regions without any visible symptoms on infected hop plants. In this study, we evaluated the influence of HLVd infection on the content and the composition of secondary metabolites in maturated hop cones, together with gene expression analyses of involved biosynthesis and regulation genes for Saaz, Sládek, Premiant and Agnus cultivars. We confirmed that the contents of alpha bitter acids were significantly reduced in the range from 8.8% to 34% by viroid infection. New, we found that viroid infection significantly reduced the contents of xanthohumol in the range from 3.9% to 23.5%. In essential oils of Saaz cultivar, the contents of monoterpenes, terpene epoxides and terpene alcohols were increased, but the contents of sesquiterpenes and terpene ketones were decreased. Secondary metabolites changes were supported by gene expression analyses, except essential oils. Last-step biosynthesis enzyme genes, namely humulone synthase 1 (HS1) and 2 (HS2) for alpha bitter acids and O-methytransferase 1 (OMT1) for xanthohumol, were down-regulated by viroid infection. We found that the expression of ribosomal protein L5 (RPL5) RPL5 and the splicing of transcription factor IIIA-7ZF were affected by viroid infection and a disbalance in proteosynthesis can influence transcriptions of biosynthesis and regulatory genes involved in of secondary metabolites biosynthesis. We suppose that RPL5/TFIIIA-7ZF regulatory cascade can be involved in HLVd replication as for other viroids of the family Pospiviroidae

Czech hop varieties

České chmelařství bylo až do 90. let 20. století zaměřeno výhradně na pěstování jemných aromatických chmelů. Díky šlechtitelské práci se podařilo zušlechtit Žatecký poloraný červeňák, který je pěstován v devíti klonech. Později byly získány nové hybridní odrůdy z křížení vhodných rodičovských komponentů, které vykazují vyšší výkonnost při zachování pivovarské kvality. V současné době tak české chmelařství disponuje všemi typy chmelových odrůd, a to od jemně aromatických až po vysokoobsažné chmele. Jejich přehled společně s jejich popisy, vlastnostmi a charakteristikami je přehledně uveden v této publikaci