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The influence of the developmental stage of zygotic embryos and the composition and pH of the Gamborg induction medium B5 on the initiation and development of somatic embryos was investigated. The optimal medium was B5 medium with a pH value of 5.0 and without plant growth regulator, at which the highest frequency of somatic embryogenesis (56.67%) and the highest average number of somatic embryos per explant (3.35) were achieved. Somatic embryos appeared directly on the hypocotyls of the explants, without the callus stage. On zygotic embryos in the early cotyledonary phase, three times higher regeneration was achieved compared to larger embryos in the cotyledonary phase. The induction of somatic embryogenesis did not occur during the growth of explants on the medium containinig 2,4-dichlorophenoxyacetic acid, nor on zygotic embryos in the late cotyledonary phase. Random amplified polymorphic DNA analysis showed the genetic stability of somatic embryo-derived plants, which makes this newly established protocol suitable for the regeneration and propagation of desirable broccoli genotypes.

Barley is one of the world’s most important crops. Barley is used for both food and feed and is important for the production of malt. Malt quality is a complex function of barley genetics, environmental conditions during barley growth, and the technological aspects of the malting process. Due to the high heritability of more than half of the malting parameters, barley can be bred for malting quality. Marker-assisted selection (MAS) is a good way to speed up the breeding process. In this study, nine molecular markers were used to screen 115 barley varieties and breeding lines over a four-year period. The results were compared with malting quality parameters. Multicomponent correlation analysis showed a good correlation (R = 0.63; P ≤ 0.01) between marker screening results and malting quality parameters. In 93 genotypes (80.9%), agreement was found between molecular marker prediction and malting quality determination. Differences between molecular marker screening and malt quality parameters and possible improvements are discussed. The use of molecular markers in MAS is highly appreciated by barley breeders.

Several antimitotic agents were tested in three embryogenic doubled haploid (DH) lines of swede (Brassica napus ssp. napobrassica). No effect on embryogenesis was observed at the given concentrations of colchicine (5 μmol/L or 50 mg/L) and treatment time of 24 hours. Flow cytometric analysis of microspore embryos revealed a significant increase in the percentage of DH compared to the control for all substances: ethalfluralin, 62.2%; trifluralin, 58.3%; colchicine, 56.1%; amiprophos-methyl, 54.4%; pronamide, 35.0%; control, 13.3%. The occurrence of pure tetraploids was low (0–5%), mixoploids – especially n+2n – were high in all treatments, including the control (29.4–71.1%). Their presence can be explained as a consequence of spontaneous diploidisation and/or endoreduplication during embryogenesis or embryo germination.

Heading date determines rice seasonal and regional adaptation, while plant height is an important trait related to rice lodging resistance. In this study, a recombinant inbred line population was used to detect quantitative trait loci (QTLs) for both traits in long-day (LD) and short-day (SD) environments. Three and two QTLs for heading date were detected in LD and SD environments, respectively. Notably, qHD8 and qHD10 were commonly detected in both environments. Five and four QTLs for plant height were identified in LD and SD environments, respectively. Among them, qPH3, qPH5 and qPH6 showed no pleiotropic effects on heading date and were detected in both environments. These three QTLs are considered to be the primary targets for improving rice plant height. Additionally, two genomic regions exhibited pleiotropic effects on both heading date and plant height. The alleles delayed the heading date while simultaneously increasing plant height. This study indicated that most QTLs for heading date are sensitive to photoperiod and have pleiotropic effects on plant height, thereby complicating their application in breeding programs. These findings provide useful information for the breeding of rice varieties with desired heading dates and plant heights.

The lignin content of forage crops significantly affects the livestock’s forage intake and its dry matter digestibility. The brown midrib (bmr) trait is known for its association with a reduced lignin content and increased digestibility. Pearl millet inbreds having the bmr trait were derived from two populations ICMV bmr and WRajPop bmr via continued selfing up to 6–8 generations. The results from the crosses revealed the presence of the same single recessive gene that controlled the bmr in both the populations. The stable expression of the bmr gene in the new genetic background indicated that there was no effect of modifier genes. Four inbreds were identified with the stable expression of bmr (three in ICMV 155 and one in the WRajPop background) with a high biomass potential, which can serve as a bmr source in future pearl millet forage breeding programmes.

Fusarium head blight (FHB), mainly caused by Fusarium graminearum, is one of the most devastating diseases of wheat globally. FHB causes an extensive reduction in yield and reduces the grain quality through its contamination with Fusarium toxins such as deoxynivalenol (DON), T2 toxin, HT-2 toxin, nivalenol, and zearalenone. This review provides an overview of updated progress of genetic studies on the resistance to FHB, with an emphasis on the sources of resistance to FHB, resistance gene/quantitative trait loci (QTL) mining, resistance gene cloning, major FHB resistance genes/QTL identification by molecular markers, and resistance mechanisms. The achievements of resistance breeding based on phenotype selection and molecular markers was also summarised. Based on the systematic analysis of breeding limitations and utilisation of FHB resistant materials, the authors put forward three suggestions: First, to toughen the resistance identification of wheat, testing traits such as Fusarium damaged kernel and DON need special attention as visual symptoms are less reliable, resistant varieties should be popularised, and the screening the resistant genes should be strengthened; The second is to use the additive effect of quantitative resistance genes accumulated from existing varieties to reduce the cost of resistance in order to create high yielding resistant varieties. Thirdly, to enhance research and utilization of new genes.

Rf(fa), a new restoring fertility gene in rice, was previously located to a large region on Chromosome 10. The large number of genes within the region made cloning of Rf(fa) difficult. To perform the cloning and further elucidate the molecular mechanism, we reconstructed a mapping segregation population (BC₁F₁) of 12 000 plants. Using the population and polymorphism of simple sequence repeat (SSR) molecular markers, we finally mapped Rf(fa) between the two SSR molecular markers MM2000 and RM25658, within a 78.87 kb region. By de novo sequencing of a restoring line of CMS-FA hybrid rice, we obtained the genomic sequence of the mapping region, which provided the basis for the prediction of the candidate gene(s) of the target gene and for the comparison of genomic sequence differences between wild and cultivated rice. Within the mapping region, the genomic sequence of the wild rice was significantly different from that of cultivated rice. There were ten genes in the final mapping region. A pentatricopeptide repeat (PPR) protein gene was predicted as the candidate gene of Rf(fa). Our results laid a solid foundation for the final cloning and molecular mechanism analysis of the gene. The identified molecular markers tightly linked to Rf(fa) will facilitate the marker assisted selection in breeding of CMS-FA hybrid rice.

Wheat leaf rust is a devastating disease worldwide. Identification of leaf rust resistance genes in seedlings and of genes for slow rusting are important in resistance breeding and for gene deployment to control the disease. A total of 108 wheat cultivars from the Beijing and Shandong province and a set of 36 differentials, mostly near-isogenic lines in the background of Thatcher with known leaf rust resistance genes, were tested with 20 Puccinia triticina pathotypes  (FHJS1, FGBQ,PGJQ, SHJT, FHGQ, PHTT1, FHGQ, FHGQ, PHJS, THSM, FHSQ, PHST, PRSQ, FNTQ, PHGM, KHGQ, PHTT2, TGTT, FHJS2, NHHT) at the seedling stage in the greenhouse. The cultivars and differentials were also planted in the field to test their slow rusting resistance using a mixture of races at Baoding, Hebei province and Zhoukou, Henan province, for two consecutive years. Ten leaf rust resistance genes, Lr1, 9, 10, 19, 20, 24, 26, 34, 37 and 46 were identified  in the 57 commercial wheat cultivars, either singly or in combination, using molecular markers. Combined, the results from gene postulation and marker detection showed that one or more of the genes Lr1, 3, 10, 14a, 14b, 26, 36, 39, 34 and 46, were present in 57 cultivars, and that no known resistance gene was present in the remaining 51 cultivars. The resistance gene Lr26 was present in 42 cultivars, and nine cultivars contained Lr1. Lr46 was present in 10 cultivars, as indicated by the presence of the closely linked marker csLV46G22. Seven genotypes were identified as possibly carrying the gene Lr39. Lr3 and 10 were found in six and four genotypes, respectively. The ggenes Lr14b and 34 were each present in three cultivars, while evidence for the presence of Lr14a and 36 was obtained in single genotypes. Finally, 12 cultivars showed slow rusting resistance at two locations in two crop seasons. The identification of leaf rust resistance genes in Chinese wheat cultivars will be helpful for gene deployment to control leaf rust.

The CBF (C-repeat binding factors) genes play important roles in response to abiotic stress and environmental changes. In the present study, a total of 18 CBF genes were identified from a grapevine. Their domains, phylogenetics, and collinearity were analysed. The results revealed, that 18 VviCBF genes were distributed on 10 chromosomes unevenly in the grape genome. Promoter data analysis showed that the CBF gene has many cis-acting elements related to plant growth and development, light response, hormone, and abiotic stress response. We found that six VviCBF genes including, VviCBF5, VviCBF13, VviCBF14, VviCBF15, VviCBF16, and VviCBF18 differentially expressed during fruit developmental stages. Furthermore, four VviCBF genes including, VviCBF1, VviCBF3, VviCBF6, and VviCBF11 were expressed at the early stage of bud dormancy, whereas, nine VviCBF genes were expressed at the bud dormancy-breaking stage. Additionally, various VviCBFs genes respond to different abiotic and biotic stress. These findings will lay a foundation for further study of the CBF genes in bud dormancy, downy mildew, and abiotic and biotic stresses.

Knowledge of gene actions governing begomovirus resistance and plant architectural traits is a prerequisite for a successful hybrid breeding programme. Therefore, the gene actions associated with these traits were studied in two intervarietal crosses of Cucurbita moschata (C₁: Punjab Nawab × MVSR-6711 and C₂: Punjab Nawab × P-135). We used the generation mean analysis of six generations for this purpose. Significant differences between the generation means were observed for all the traits in both crosses. The parental lines differed significantly in most of the studied traits. The nature and magnitude of the gene effects of seventeen traits varied by trait and cross. A simple additive dominance model was adequate for the internode number, leaf length and width, petiole length, fruit weight and cavity diameter in C₁ and the number of fruits/plant in C₂. The non-allelic interaction was found to be significant for a majority of the traits including the per cent disease index of the squash leaf curl China virus, tomato leaf curl New Delhi virus and their mixed infections, which indicated, that recurrent selection in biparental progeny might be useful for the accumulation of genes with additive effects. Duplicate epistasis was observed for the vine, internodal and peduncle length in C₁ and the internode number, petiole and peduncle length, peduncle and fruit polar diameter in C₂. This information will help to establish a breeding program for the simultaneous improvement of virus resistance and yield traits in pumpkins.

The present study was conducted to explore the variability generated through recombination breeding for nine economically important traits in Indian mustard (Brassica juncea L. Czern & Coss.). Delineation of the inbred lines to different gene pools, based on genetic diversity, enables their utilisation in hybrid breeding. The unweighted pair group method with arithmetic mean (UPGMA) and a Euclidean distance matrix was used to delineate the inbred lines to clusters. The variability was studied using the range and coefficients of variation of the traits. Significant variability was observed for all studied traits except for oil content and days to maturity. 128 Indian mustard genotypes were grouped into four distinct gene pools based on genetic diversity. A set of 20 most diverse genotype combinations was produced. Promising inbred lines were identified and recommended as donors for the respective trait. The pedigree analysis of the inbred line groups revealed, that recombination breeding caused a large diversity as confirmed by the assignment of inbred lines with the same parentage to specific clusters.

Grafting is the most important means of breeding peach, plum, apricot, and other fruit trees, and the selection of the rootstock is crucial to the quality of the grafting and the yield of the products. The traditional commonly used peach rootstock is susceptible to root-knot nematode infections, resulting in a decreased yield, while a variety of cherry plum rootstocks, Mirabolano 29C, is resistant to root-knot nematode. In this study, root-knot nematode infection experiments on seedlings of traditional peach rootstocks and Mirabolano 29C confirmed that Mirabolano 29C was indeed more resistant to root-knot nematodes. At the same time, we compared the roots of the root-knot nematode uninfected and infected Mirabolano 29C by transcriptome sequencing and found 3 176 differentially expressed genes. A further functional enrichment analysis of these genes found that the secondary metabolites, phenylpropane and flavonoids, may be responsible for the high resistance of Mirabolano 29C to root-knot nematodes. These results can provide a reference value for the disease resistance breeding of rootstocks.

Apples are available all year round since they can be stored for long time. However, the expression of the major apple allergen Mal d 1 can increase in the fruit during storage and incease so the risk of allergies in sensitive consumers. Therefore, we studied the change in the expression of the Mal d 1 gene during storage in the modern cultivar UEB 32642 (known under the brand name Opal^®) and the cultivar Gala Brookfield (cv. Gala) as a reference. The cultivars were stored under two different conditions, ultra-low oxygen (ULO) and standard cold conditions. The gene expression was evaluated both in fresh fruits and in fruits stored for four, six, and nine months. Nine isoforms of the gene Mal d 1 with the highest published expression were quantified using real-time PCR. The most expressed isoforms Mal d 1.01, Mal d 1.02 and Mal d 1.06A were found in the fresh and also in the stored fruits. The expression of the Mal d 1.03G and Mal d 1.06D isoforms was higher the sored fruits. Our study confirmed that (i) Opal^® had a lower overall expression of the Mal d 1 gene than cv. Gala, both in the fresh and stored fruits; (ii) standard cold storage is superior in preserving lower Mal d 1 levels in Opal^®apples compared to the ULO conditions; and (iii) less expressed isoforms may be responsible for the general increase in the Mal d 1 gene expression during storage.

Medicago sativa is the most widely cultivated forage legume and one of the most economically valuable crops throughout the world. Qingda no.1 (Medicago sativa L. cv. Qingda no.1) is an excellent alfalfa local variety with strong cold, drought and salt resistance in the three rivers source area of Qinghai. In this study, the whole chloroplast (cp) genome of Qingda no.1 was sequenced, assembled and its structure was analysed by the Illumina high-throughput sequencing technology. The results showed that the chloroplast genome of Qingda no.1 exhibits no obvious typical quadripartite structure; the total length of the chloroplast genome is 125 637 bp; the chloroplast genome contained 111 genes, including 77 protein-coding genes, 30 tRNA genes, and 4 rRNA genes, with an overall GC content of 38.33%. The relative synonymous codon usage showed that 68.67% of the codons RSCU > 1 in Qingda no.1, with the preference ending with A and T. The simple sequence repeat (SSR) analysis identified 62 SSR loci. The phylogenetic analysis of the cp genome, Qingda no.1 clustered closely with Medicago sativa KU321683 (Medicago sativa L. cv. KU321683). These results are helpful for the further study of the Qingda no.1 adaptation mechanism to high altitude stress environments.

Kaliurang is one of the local taro cultivars in Indonesia, potentially due to its high productivity and delicacy. This study analysed morpho-genetic variation between one diploid and three tetraploid Kaliurang taro clones from in vitro polyploid induction after plantlet acclimatization in the greenhouse for 6 weeks. Plants’ morphological characters were analysed using the unweighted pair group method with arithmetic mean (UPGMA) method based on 50 characters according to the taro descriptor from the International Plant Genetic Resources Institute (IPGRI). Furthermore, a morphometric characterization based on the Euclidean distance of 17 digitations from mature leaves, was analysed with the Analysis Phylogenic and Evolution package in R software. DNA band pattern was also performed with ISSR to analyse the clone’s genetic variance. The results showed morpho-genetic character diversity in diploid and tetraploid plants. A plant morphological study revealed that 22 out of 50 characters were distinct, with similarity coefficients ranging from 0.35 to 0.78. Leaf geometric morphometric analysis showed changes in five digitations and formed three clusters. Twelve ISSR primers out of twenty amplified the sequence of the Kaliurang taro genome to yield two clusters with a similarity coefficient of 0.71–0.83. Based on these three characterization approaches, tetraploid clones (K2 and K3) consistently differed morphologically from diploid clones (K0).

By choosing appropriate candidate reference genes (CRGs) and standardizing qPCR data, more accurate experimental data can be obtained. Herein, the expression stability of alpha-tubulin1 (TUA1), beta-tubulin (TUB), beta-tubulin 1 (TUB1), beta-tubulin 5 (TUB5), actin 1 (ACT1), actin 97 (ACT97), molecular chaperone dnaj (DNAJ), adenine phosphoribosyl transferase (APT), and histone H4 (HIS4) genes from Paulownia fortunei (Seem.) Hemsl. under different experimental conditions (different tissues, drought, salinity, Cd, and Cr treatments) was assessed with four statistical tools: RefFinder, BestKeeper, NormFinder, and geNorm. Notably, TUA1 and TUB5 were identified as CRGs for different tissues, ACT97 and TUB1 for drought treatment, ACT97 and APT for salinity treatment, TUB1 and ACT97 for Cd treatment, and DNAJ, TUB1 and TUB5 for Cr treatment. Furthermore, the results of “total” group, V₄/V₅ > 0.15 and V₅/V₆ < 0.15 revealed that the CRGs or gene combinations, which could meet all the test conditions, were not easy to identify. To further verify the reliability of CRGs, the expression levels of paulownia fortunei cellulose synthase A catalytic subunit2 (PfCesA2) and paulownia fortunei glutathione reductase (GR) genes were analysed. The expression patterns were different when the unstable CRGs were used for normalization compared to when the stable CRGs and combination were used for normalization. This study will lay a foundation for study on the expression levels of key genes from P. fortunei seedlings.

To explore the role of WRKY transcription factors (TFs) in the resistance process of Qingke (Hordeum vulgare L. var. nudum Hook. f.), leaves of the leaf stripe disease-resistant variety Kunlun 14 and the susceptible variety Z1141 were sequenced by transcriptome sequencing (RNA-seq). A differentially expressed gene HvnWKRY1 was identified, and its disease-resistance function was preliminarily analysed. The result showed that the open reading frame (ORF) of the gene was 1 062 bp and encoded 354 amino acids. It contained the conserved WRKY domain (273–351) and belonged to the WRKY protein family. The phylogenetic tree results showed that HvWRKY1 was most closely related to Hordeum vulgare L. The WRKY family of Qingke, barley, maize and rice were divided into categories I, II, and III, among which HvWRKY1 was located in group III. Results of the quantitative real-time fluorescence PCR (qRT-PCR) showed that the expression of HvWRKY1 was significantly (P < 0.01) higher in leaf stripe infected leaves of Kunlun 14 than that of Z1141. In Arabidopsis thaliana transformed with HvWRKY1, resistance to Botrytis cinerea was enhanced. The RNA-seq analysis showed there were 824 differentially expressed genes (DEGs). Data of the Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment indicated, that a plant-pathogen interaction pathway was enriched. This study is expected to provide a theoretical basis for further studies of functioning of  the Qingke gene HvWRKY1 in resistance to the leaf stripe disease.

The article was retracted by the authors based on detected errors in the data processing.

The relationship between the early ground cover and the grain yield in winter wheat is not yet fully understood. In a winter wheat breeding programme, selection for early ground cover is traditionally made using visual scoring. Although visual scoring is preferred as a phenotypic screening tool by wheat breeders, its output may not be reliable, as it requires experience. A smartphone camera-based digital image technique can be recommended as a feasible, reliable, repeatable, affordable, and fast selection tool for early ground cover in wheat as an alternative to visual scoring. For this purpose, two wheat trials were conducted in the 2017-2018 and 2019-2020 seasons. In both seasons, 215 wheat genotypes in total, together with three checks from spring wheat, were tested under rain-fed conditions in the spring wheat zone in Turkey. All the tested wheat genotypes were grouped into spring, facultative, and winter growth habit using visual scoring. Simultaneously, photos were taken from each plot with a smartphone camera, and the early ground cover (%) was estimated using the smartphone camera-based digital image technique. The relationships between grain yield, visual scoring, and early ground cover could so be estimated. In both seasons, significant negative correlation between grain yield and visual scoring (r = -0.679** and r = -0.704**, respectively) and significant positive correlation between the grain yield and the early ground cover (r = 0.745** and r = 0.747**, respectively) were observed. The correlation between visual scoring and early ground cover were negative (r = -0.862** and r = -0.926**, respectively). The broad sense heritability estimates in both seasons were 0.51 and 0.85, respectively, for early ground cover, 0.91 and 0.94 for visual scoring, and 0.86 and 0.69 for grain yield. In this study, we revealed that testing winter wheat genotypes in the spring wheat zone rather than in the winter wheat zone could be a more effective way to unveil the positive relationship between the early ground cover and the grain yield. We have shown that the smartphone-based digital image technique is a useful selection tool for early ground cover in winter wheat.

Rice is one of the frontline cereals in the world and the major cultivated crop in Bangladesh. A total of eleven simple sequence repeats (SSRs) and thirteen sequence-tagged site (STS) markers were used to characterize twenty-four rice cultivars in Bangladesh. Twenty-four markers generated 60 alleles with 2.5 alleles per locus. The average polymorphism information content (PIC) value was 0.40, while the mean value of heterozygosity, gene diversity, and major allele frequency were recorded as 0.10, 0.48 and 0.62, respectively. However, the SSR markers showed more specificity and a higher discrimination power than the STS markers. The cluster analysis displayed four major clusters with a genetic similarity coefficient value of 0.73. The morphological analyses of the grain identified that Binadhan-20 and BRRI dhan34 had the longest and the shortest seed size, respectively, with a variable correlation between the seed length, width and length/width ratio. The phenol reaction test distinguished seven cultivars as japonica and seventeen cultivars as indica or an intermediate type. All these results regarding the phenotypic data and marker information will be useful for parental selection in modern rice breeding programmes.

We used two chloroplast gene regions (matK and rbcL) as a tool for the identification of 33 local conifer species. All 136 sequences, 101 newly generated (14 species for gene matK; 16 species for gene rbcL) and 35 retrieved from the GenBank, were used in the analysis. The highest genetic distance (matK region) was recorded between the species in Cupressaceae with an average of 5% (0.1-8.5), Podocarpaceae with an average of 6% (0-8.5), Taxaceae with an average of 5% (0.2-0.5) and Pinaceae with an average of 20.4% (0.8-54.1). The rbcL region showed a low genetic distance between the species in Cupressaceae 2% (0-3.3), Podocarpaceae 3% (0.6-3.4), Taxaceae 1% (0-2.1) and Pinaceae 1.2% (0-5.82). The phylogenetic analyses using the Maximum likelihood (ML) and Bayesian inference (BI) bootstrap values obtained at the branching nodes of each species ranged from 62 to 100% (Maximum likelihood bootstrap - MLBS and Bayesian posterior probabilities - BPP) for the matK gene; from 66 to 100% (MLBS) and 60 to 100% (BPP) for the rbcL region. The rbcL region was not identified between the species of Taxaceae and Cephalotaxaceae. The matK gene region was very clear in the different species among the families (Cupressaceae, Podocarpaceae, and Cephalotaxaceae) and unsuitable for identifying closely related species in Amentotaxus (Taxaceae) and Pinus (Pinaceae). The gene (matK) is a useful tool as a barcode in the identification of conifer species of Cupressaceae, Podocarpaceae, and Cephalotaxaceae in Vietnam.

In 2016-2018 virulence of the Czech wheat leaf rust population was studied on Thatcher near-isogenic lines, carrying different Lr genes, and 130 leaf rust isolates. Virulence to Lr9 was found only sporadically. Virulence frequency to Lr2a, Lr2b, Lr2c and Lr28 was lower than in previous years. All tested isolates were avirulent to Lr19. Lr24 conditioned resistance to majority of isolates. Nineteen recently registered Czech cultivars were tested with six isolates of the pathogen and Lr genes were postulated. Presence of genes Lr1, Lr10, Lr19, Lr24, Lr26, Lr28, Lr34 and Lr37 was tested by molecular markers. Lr37 prevailed, followed by Lr genes 10, 24, 28, 1 and 26; genes Lr19 and Lr34 were not determined.

The designation of traditional varieties of grapevine is usually based on verbal information or very dated records. Old rare cultivars found in the Czech Republic were identified by Simple Sequence Repeat (SSR) analysis, a generally accepted method for cultivar identification. These cultivars are primarily maintained in a national collection of genetic resources. Finally a total of 102 candidate genotypes was selected where 49 traditional varieties were identified on the base of nine SSR loci compared with the European Vitis Database. Thirty-six items were registered under the correct designation. The remaining genotypes included four clones, and two genotypes could be described as synonyms. Seven genotypes were found to be incorrectly marked. For three of them, the correct name was found in the database under their SSR profile and four items were considered to be unique as no identical profile was found.

Traditional hop (Humulus lupulus L.) cultivars have been used in the brewing industry for a long time. Globally, about ten new breeding lines were released to the market in each decade from ~1970 to 1999. Since 2006, the rate of release of new cultivars has increased tenfold. It is, therefore, important to identify their genotype and origin. Molecular genetic methods based on DNA are the most appropriate technology for this purpose. Recently, we developed an efficient marker system for the authenticity control of hop genotypes based on expressed sequence tag-simple sequence repeats (EST-SSR). In the present study, we enlarged the previously established EST-SSR set with 27 new polymorphic markers and evaluated molecular genetic variability within 135 traditional and new world hop cultivars. Two sets of 10 markers effectively differentiated all used cultivars, with the exception of cultivars derived from the same original genotype such as Saaz, Spalt, Tettnang and Nadwislawsky. Results of molecular genetic variability analyses corresponded with the genealogical and geographical origin of the key cultivars.

The scientific report presents results of our studies on the gene Pch1, conferring resistance to eyespot disease in wheat, caused by the fungus Occulimacula spp. The presence of the gene Pch1 in wheat cultivars was analysed using the molecular marker Xorw1. In total 106 wheat cultivars registered in the Czech Republic and 54 breeding lines were tested. The gene Pch1 was found in the cultivars Annie, Beduin, Hermann, Iridium, Manager and Princeps and in three breeding lines. Some of these cultivars were tested for eyespot resistance in field trials and showed a high level of resistance. Cv. Hermann was the most resistant winter wheat cultivar in our experiments in the last two years. The method of artificial infection by Oculimacula spp. was optimized.

Wild Triticum and Aegilops species are increasingly used in wheat breeding programmes around the world as donors of genes conferring resistance to biotic and abiotic stresses, as well as of genes that contribute to the improvement of grain quality. In the present study, thirty-nine accessions of diploid species with the A genome (Triticum boeoticum and T. urartu) were evaluated for the presence of the genes conferring resistance to powdery mildew (Blumeria graminis) and leaf rust (Puccinia recondita) using both inoculation tests and sequence tagged sites (STS) marker analyses in order to find correspondence between STS markers and resistance as a trait. The most resistant entries were T. boeoticum accessions. All the marked Lr and Pm resistance genes (Pm1, Pm2, Pm3, Lr10, Lr47, Lr25 and Lr28) were identified in the check T. aestivum cultivar Bezostaya 1. The resistance to powdery mildew in the material studied was conferred by the combination of the Pm1 gene with either Pm2 or Pm3. The Pm1 and Pm3 markers appeared to be suitable for tracking these powdery mildew resistance genes, while the Pm2 gene marker cannot be considered as usable in various genetically different wheat accessions. The presence of the genes Lr25, Lr28 and Lr47 seems to be particularly useful for obtaining leaf rust resistance in T. boeoticum and T. urartu species.