A recent rise in the global brewery sector has increased the demand for high-quality, late summer hops. The effects of ongoing and predicted climate change on the yield and aroma of hops, however, remain largely unknown. Here, we combine meteorological measurements and model projections to assess the climate sensitivity of the yield, alpha content and cone development of European hops between 1970 and 2050 CE, when temperature increases by 1.4 °C and precipitation decreases by 24 mm. Accounting for almost 90% of all hop-growing regions, our results from Germany, the Czech Republic and Slovenia show that hop ripening started approximately 20 days earlier, production declined by almost 0.2 t/ha/year, and the alpha content decreased by circa 0.6% when comparing data before and after 1994 CE. A predicted decline in hop yield and alpha content of 4-18% and 20-31% by 2050 CE, respectively, calls for immediate adaptation measures to stabilize an ever-growing global sector.
- MeSH
- Humulus * MeSH
- klimatické změny MeSH
- odoranty MeSH
- teplota MeSH
- zemědělství metody MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Hop (Humulus lupulus L.) is an important commercial crop known for the biosynthesis of valuable specialized secondary metabolites in glandular trichomes (lupulin glands), which are used for the brewing industry. To achieve burgeoning market demands is the essentiality of comprehensive understanding of the mechanisms of biosynthesis of secondary metabolites in hop. Over the past year, several studies using structural biology and functional genomics approaches have shown that Mediator (MED) serves as an integrative hub for RNAP II-mediated transcriptional regulation of various physiological and cellular processes, including involvement of MED5a and MED5b in hyperaccumulation of phenylpropanoid in A. thaliana. In the present work, an unprecedented attempt was made to generate Hlmed5a/med5b double loci mutant lines in hop using a CRISPR/Cas9-based genome editing system. The Hlmed5a/med5b double loci mutant lines showed reduced expression of structural genes of the flavonoid, humulone, and terpenoid biosynthetic pathways, which was more pronounced in the lupulin gland compared to leaf tissue and was consistent with their reduced accumulation. Phenotypic and anatomical observations revealed that Hlmed5a/med5b double loci mutant line exhibited robust growth, earlier flowering, earlier cone maturity, reduced cone size, variations in floral structure patterns, and distorted lupulin glands without any remarkable changes in leaf morphology, intensity of leaf color, and chlorophyll content. Comparative transcriptome analysis of leaf and lupulin gland tissues indicates that the expression of enzymatic genes related to secondary metabolite biosynthesis, phytohormone biosynthesis, floral organs, flowering time, and trichome development, including other genes related to starch and sucrose metabolism and defense mechanisms, were differentially modulated in the Hlmed5a/med5b lines. The combined results from functional and transcriptomic analyses illuminates the pivotal function of HlMED5a and HlMED5b in homeostasis of secondary meatbolites accumulation in hop.
- Klíčová slova
- Bitter acids, Chalcone synthase, Flavonoids, Humulus lupulus, Mediator complex, Transcription regulation, Transcriptome analysis,
- MeSH
- CRISPR-Cas systémy MeSH
- genomika MeSH
- Humulus * genetika MeSH
- stanovení celkové genové exprese MeSH
- transkriptom MeSH
- Publikační typ
- časopisecké články MeSH
The fate of during brewing of pesticides (organic compounds and copper) from hops was determined to reveal linkages between various pesticide sequences applied in hop yards and the level of pesticides in beer. For this purpose, laboratory-scale brewing trials were carried out with conventional hops from four localities in which pest control spray programs varied. Pesticide residue analysis in samples of hopped wort, young beer, and beer was carried out by liquid chromatography in tandem with mass spectrometry (LC-MS/MS). Cu concentrations were determined using inductively coupled plasma mass spectrometry (ICP-MS). The transfer rates (%) of individual pesticides were calculated to demonstrate their ability to be transferred from hops to the brewed solutions. The pesticides exhibited different transfer rates correlating well with their log p values; however, the obtained transfer data were not related to their concentration in hops. The average transfer rates calculated for ametoctradin (15% ± 5%), mandipropamid (38% ± 4%), boscalid (48% ± 5%), and azoxystrobin (47% ± 2%) increased in good correlation with their descending log P values. On the contrary, the transfer rates of copper residues were related to residual concentrations of copper in hops and exhibited logarithmic dependency. The carryover of the sum of all pesticides in the four samples ranged from 36% to 49%, averaging 42% ± 6%. The data showed no substantial influence of various pesticide spray sequences on the percentages of overall pesticide residues carried over into beer.
- Klíčová slova
- LC-MS/MS, Pesticide residues, beer, copper, hops, laboratory scale brewing trials,
- MeSH
- agrochemikálie analýza MeSH
- chromatografie kapalinová MeSH
- Humulus * chemie MeSH
- měď analýza MeSH
- pesticidy * analýza MeSH
- pivo analýza MeSH
- průmyslové fungicidy * analýza MeSH
- rezidua pesticidů * analýza MeSH
- tandemová hmotnostní spektrometrie MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- agrochemikálie MeSH
- měď MeSH
- pesticidy * MeSH
- průmyslové fungicidy * MeSH
- rezidua pesticidů * MeSH
Viroids are small, non-coding, pathogenic RNAs with the ability to disturb plant developmental processes. This dysregulation redirects the morphogenesis of plant organs, significantly impairing their functionality. Citrus bark cracking viroid (CBCVd) causes detrimental developmental distortions in infected hops (Humulus lupulus) and causes significant economic losses. CBCVd can infect cells and tissues of the model plant tobacco (Nicotiana tabacum), provided it is delivered via transgenesis. The levels of CBCVd in tobacco were enhanced in plant hybrids expressing CBCVd cDNAs and either the tobacco or hop variant of TFIIIA-7ZF, a viroid-mediated splicing derivative of transcription factor IIIA, which is important for viroid replication by DNA-dependent RNA polymerase II. The TFIIIA-7ZF variants can change the tobacco morphogenesis if expressed in leaves and shoots. In addition to the splitting of shoots, the "pathomorphogenic" network in hybrid plants expressing CBCVd and HlTFIIIA-7ZF induced leaf fusions and malformations. Moreover, CBCVd can dramatically change another morphogenesis into teratomic and petal-like tissues if propagated above some limit in young transgenic tobacco microspores and anthers. By comparative RNA profiling of transgenic tobacco shoots bearing TFIIIA-7ZFs and CBCVd-transformed/infected anthers, we found a differential expression of many genes at p < 0.05. As the main common factor showing the differential up-regulation in shoot and anther tissues, a LITTLE ZIPPER 2-like transcription factor was found. We propose that this factor, which can interact as a competitive inhibitor of the also dysregulated homeobox-leucin zipper family protein (HD-ZIPIII) in apical meristem, is essential for a network responsible for some morphological changes and modifications of plant degradome within shoot meristem regulation and secondary xylem differentiation.
- Klíčová slova
- Nicotiana tabacum, plant transformation, regulation of plant morphogenesis, transcription factors, transcriptome profiling, viroid pathogenesis,
- MeSH
- Citrus * metabolismus MeSH
- Humulus * genetika MeSH
- kůra rostlin metabolismus MeSH
- malá nekódující RNA * MeSH
- nemoci rostlin genetika MeSH
- tabák genetika metabolismus MeSH
- transkripční faktor TFIIIA genetika metabolismus MeSH
- viroidy * metabolismus MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- malá nekódující RNA * MeSH
- transkripční faktor TFIIIA MeSH
Hop (Humulus lupulus) biosynthesizes the highly economically valuable secondary metabolites, which include flavonoids, bitter acids, polyphenols and essential oils. These compounds have important pharmacological properties and are widely implicated in the brewing industry owing to bittering flavor, floral aroma and preservative activity. Our previous studies documented that ternary MYB-bHLH-WD40 (MBW) and binary WRKY1-WD40 (WW) protein complexes transcriptionally regulate the accumulation of bitter acid (BA) and prenylflavonoids (PF). In the present study, we investigated the regulatory functions of the R2R3-MYB repressor HlMYB7 transcription factor, which contains a conserved N-terminal domain along with the repressive motif EAR, in regulating the PF- and BA-biosynthetic pathway and their accumulation in hop. Constitutive expression of HlMYB7 resulted in transcriptional repression of structural genes involved in the terminal steps of biosynthesis of PF and BA, as well as stunted growth, delayed flowering, and reduced tolerance to viroid infection in hop. Furthermore, yeast two-hybrid and transient reporter assays revealed that HlMYB7 targets both PF and BA pathway genes and suppresses MBW and WW protein complexes. Heterologous expression of HlMYB7 leads to down-regulation of structural genes of flavonoid pathway in Arabidopsis thaliana, including a decrease in anthocyanin content in Nicotiana tabacum. The combined results from functional and transcriptomic analyses highlight the important role of HlMYB7 in fine-tuning and balancing the accumulation of secondary metabolites at the transcriptional level, thus offer a plausible target for metabolic engineering in hop.
- Klíčová slova
- Bitter acids, Chalcone synthase, Flavonoids, Humulus lupulus, R2R3 MYB, RNA sequencing,
- MeSH
- Arabidopsis * genetika metabolismus MeSH
- flavonoidy metabolismus MeSH
- Humulus * genetika MeSH
- regulace genové exprese u rostlin MeSH
- rostlinné proteiny metabolismus MeSH
- transkripční faktory metabolismus MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- flavonoidy MeSH
- rostlinné proteiny MeSH
- transkripční faktory MeSH
The aim of this study was to determine the presence of zoocide (insecticide and miticide) residues in hops collected in three hop-growing regions located in the Czech Republic, and to assess their zoocide profiles and residue levels in terms of variability in temperature and precipitation across the 2018-2020 seasons. Furthermore, the weather factors that influenced the occurrence of hop pests are described and discussed. During our 3-year survey, a total of 120 samples of whole-cone hops samples harvested in three hop-growing regions were analysed for the presence of 29 insecticides and miticides using the modified QuEChERS extraction method, followed by liquid chromatography-tandem mass spectrometry and gas chromatography-tandem mass spectrometry. A majority, 119 of 120 samples, contained a residue of at least one of the active substances surveyed in this study, and 34 analysed samples contained multiple residues with three to four zoocides presented. Concerning the most frequently detected zoocide residues, spirotetramat and/or its metabolites were found in 94.2% of the samples at levels ranging from 0.02 to 1.08 mg/kg. Of the other zoocides surveyed, residues of fenpyroximate, hexythiazox, bifenazate and lambda-cyhalothrin were routinely found in hop cone samples. Obtained data were then used for evaluating seasonal and geographical variations in the profile of zoocide residues among the hop-growing regions in the years 2018-2020, and the compliance with legal regulations concerning the use of zoocides on hops was ascertained. The results showed that (1) the profile and levels of zoocide residues found in the samples reflected seasonal prevalence of pest infestation on hop plants; (2) the strategy to control pests (especially aphids) used in most of hop yards was consistent across the seasons; and (3) a concentration of spirotetramat residues less than 1 mg/kg was typical for hops grown in the Czech Republic.
- Klíčová slova
- Insecticides, MRL, alfalfa snout beetle, damson-hop aphid, hop flea beetle, miticides, residues, two-spotted spider mite,
- MeSH
- akaricidy * analýza MeSH
- Humulus * chemie MeSH
- insekticidy * analýza MeSH
- plynová chromatografie s hmotnostně spektrometrickou detekcí metody MeSH
- rezidua pesticidů * analýza MeSH
- roční období MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Česká republika MeSH
- Názvy látek
- akaricidy * MeSH
- insekticidy * MeSH
- rezidua pesticidů * MeSH
Verification of clonal identity of hop (Humulus lupulus L.) cultivars within breeding programs and germplasm collections is vital to conserving genetic resources. Accurate and economic DNA-based tools are needed in dioecious hop to confirm identity and parentage, neither of which can be reliably determined from morphological observations. In this study, we developed two fingerprinting sets for hop: a 9-SSR fingerprinting set containing high-core repeats that can be run in a single PCR reaction and a kompetitive allele specific PCR (KASP) assay of 25 single nucleotide polymorphisms (SNPs). The SSR set contains a sex-linked primer pair, HI-AGA7, that was used to genotype 629 hop accessions from the US Department of Agriculture (USDA) National Clonal Germplasm Repository (NCGR), the USDA Forage Seed and Cereal Research (FSCR), and the University of Nebraska-Lincoln (UNL) collections. The SSR set identified unique genotypes except for 89 sets of synonymous samples. These synonyms included: cultivars with different designations, the same cultivars from different sources, heat-treated clones, and clonal variants. Population structure analysis clustered accessions into wild North American (WNA) and cultivated groups. Diversity was slightly higher in the cultivated samples due to larger sample size. Parentage and sib-ship analyses were used to identify true-to-type cultivars. The HI-AGA7 marker generated two male- and nine female-specific alleles among the cultivated and WNA samples. The SSR and KASP fingerprinting sets were compared in 190 samples consisting of cultivated and WNA accession for their ability to confirm identity and assess diversity and population structure. The SSR fingerprinting set distinguished cultivars, selections and WNA accessions while the KASP assays were unable to distinguish the WNA samples and had lower diversity estimates than the SSR set. Both fingerprinting sets are valuable tools for identity confirmation and parentage analysis in hop for different purposes. The 9-SSR assay is cost efficient when genotyping a small number of wild and cultivated hop samples (<96) while the KASP assay is easy to interpret and cost efficient for genotyping a large number of cultivated samples (multiples of 96).
- MeSH
- alely MeSH
- fylogeneze MeSH
- genetická variace MeSH
- genotyp MeSH
- Humulus * genetika MeSH
- mikrosatelitní repetice genetika MeSH
- polymerázová řetězová reakce MeSH
- šlechtění rostlin MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Research Support, U.S. Gov't, Non-P.H.S. MeSH
BACKGROUND: Hop (Humulus lupulus L.) bitter acids are valuable metabolites for the brewing industry. They are biosynthesized and accumulate in glandular trichomes of the female inflorescence (hop cone). The content of alpha bitter acids, such as humulones, in hop cones can differentiate aromatic from bitter hop cultivars. These contents are subject to genetic and environmental control but significantly correlate with the number and size of glandular trichomes (lupulin glands). RESULTS: We evaluated the expression levels of 37 genes involved in bitter acid biosynthesis and morphological and developmental differentiation of glandular trichomes to identify key regulatory factors involved in bitter acid content differences. For bitter acid biosynthesis genes, upregulation of humulone synthase genes, which are important for the biosynthesis of alpha bitter acids in lupulin glands, could explain the higher accumulation of alpha bitter acids in bitter hops. Several transcription factors, including HlETC1, HlMYB61 and HlMYB5 from the MYB family, as well as HlGLABRA2, HlCYCB2-4, HlZFP8 and HlYABBY1, were also more highly expressed in the bitter hop cultivars; therefore, these factors may be important for the higher density of lupulin glands also seen in the bitter hop cultivars. CONCLUSIONS: Gene expression analyses enabled us to investigate the differences between aromatic and bitter hops. This study confirmed that the bitter acid content in glandular trichomes (lupulin glands) is dependent on the last step of alpha bitter acid biosynthesis and glandular trichome density.
- Klíčová slova
- Bitter acids, Differential gene expression, Glandular trichome development, Hop, Humulus lupulus, Lupulin gland,
- MeSH
- Humulus metabolismus MeSH
- transkripční faktory metabolismus MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- transkripční faktory MeSH
In recent years, the interest in the health-promoting effects of hop prenylflavonoids, especially its estrogenic effects, has grown. Unfortunately, one of the most potent phytoestrogens identified so far, 8-prenylnaringenin, is only a minor component of hops, so its isolation from hop materials for the production of estrogenically active food supplements has proved to be problematic. The aim of this study was to optimize the conditions (e.g., temperature, the length of the process and the amount of the catalyst) to produce 8-prenylnaringenin-rich material by the magnesium oxide-catalyzed thermal isomerization of desmethylxanthohumol. Under these optimized conditions, the yield of 8-prenylnaringenin was 29 mg per 100 gDW of product, corresponding to a >70% increase in its content relative to the starting material. This process may be applied in the production of functional foods or food supplements rich in 8-prenylnaringenin, which may then be utilized in therapeutic agents to help alleviate the symptoms of menopausal disorders.
- Klíčová slova
- 8-prenylnaringenin, desmethylxanthohumol, estrogenic activity, hop, phytoestrogens, prenylflavonoids,
- MeSH
- flavanony chemie metabolismus MeSH
- flavonoidy chemie metabolismus MeSH
- fytoestrogeny chemie metabolismus MeSH
- Humulus chemie MeSH
- katalýza MeSH
- lidé MeSH
- oxid hořečnatý chemie metabolismus MeSH
- pivo analýza MeSH
- potravní doplňky analýza MeSH
- propiofenony chemie metabolismus MeSH
- rostlinné extrakty metabolismus MeSH
- rostlinné přípravky chemie metabolismus MeSH
- teplota MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- 8-prenylnaringenin MeSH Prohlížeč
- flavanony MeSH
- flavonoidy MeSH
- fytoestrogeny MeSH
- oxid hořečnatý MeSH
- propiofenony MeSH
- rostlinné extrakty MeSH
- rostlinné přípravky MeSH
- xanthohumol MeSH Prohlížeč
Long non-coding RNAs (lncRNAs) are a highly heterogeneous class of non-protein-encoding transcripts that play an essential regulatory role in diverse biological processes, including stress responses. The severe stunting disease caused by Citrus bark cracking viroid (CBCVd) poses a major threat to the production of Humulus lupulus (hop) plants. In this study, we systematically investigate the characteristics of the lncRNAs in hop and their role in CBCVd-infection using RNA-sequencing data. Following a stringent filtration criterion, a total of 3598 putative lncRNAs were identified with a high degree of certainty, of which 19% (684) of the lncRNAs were significantly differentially expressed (DE) in CBCVd-infected hop, which were predicted to be mainly involved in plant-pathogen interactions, kinase cascades, secondary metabolism and phytohormone signal transduction. Besides, several lncRNAs and CBCVd-responsive lncRNAs were identified as the precursor of microRNAs and predicted as endogenous target mimics (eTMs) for hop microRNAs involved in CBCVd-infection.
- Klíčová slova
- Citrus bark cracking viroid, Genomics, Humulus lupulus, Long non-coding RNAs, Plant defense, RNA-sequencing,
- MeSH
- Citrus * genetika MeSH
- Humulus * genetika MeSH
- kůra rostlin MeSH
- nemoci rostlin genetika MeSH
- RNA dlouhá nekódující * genetika MeSH
- stanovení celkové genové exprese MeSH
- viroidy * genetika MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- RNA dlouhá nekódující * MeSH
