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Wheat stripe rust, caused by Puccinia striiformis Westend. f.sp. tritici Eriks (Pst), is one of the most important diseases of bread wheat worldwide. Breeding resistant wheat cultivars is the most economical, effective and environmentally friendly way for controlling wheat stripe rust in China. The Romanian wheat line Fundulea 900 showed good resistance to wheat stripe rust at the adult stage. The present study aimed to map the quantitative trait loci (QTLs) for stripe rust resistance in 176 F_2:6 recombinant inbred lines (RIL) derived from the cross of Fundulea 900 × Thatcher. The RIL population was phenotyped for stripe rust (YR) severity at Mianyang in the Sichuan province and Baoding in the Hebei province in the 2016/2017 and 2017/2018 cropping seasons. SSR markers combined with a preferred screened group (PSG) analysis were used to identify the QTLs for stripe rust in the population. Three QTLs for stripe rust resistance were mapped on chromosomes 1AL, 7BL and 7DS, respectively. All three QTLs originated from Fundulea 900 and were detected in all the environments. The QTL on 7DS was provided by the known resistance gene Yr18/Lr34. The two QTLs on chromosomes 1AL and 7BL were explained by 9.2 to 21.5% and 5.1 to 10.1% of the phenotypic variance, respectively and might be new QTLs. The QTLs identified in the study and their closely linked markers can be used for marker-assisted selection (MAS) in wheat breeding programmes.

For the wide adoption of soybean varieties, it is desirable, that they are Kunitz trypsin inhibitor (Kti) free and resistant to yellow mosaic disease (YMD). The soybean variety SL525 with YMD resistance was crossed with the YMD susceptible variety NRC101 with a null kti allele. The F₅ progeny derived from the cross was screened with two simple sequence repeat (SSR) markers (satt409 and satt322) linked with the null kti allele and the YMD resistance, respectively, and one null kti allele-specific marker. The presence of both desirable traits was further confirmed with the phenotypic data which showed good correlation with the genotypic data. The yield potential of fourteen such identified genotypes having both desirable traits was either at par or superior to SL525, hence, represent improved versions of SL 525.

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.

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.

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.

Sorghum is an important crop, and starch and phenolic compounds are major and important components in the sorghum grain. However, the underlying critical genetic elements contributing to the rich portfolio of nutrients in sorghum grains are largely unknown. Transcriptomic methods were employed to characterize the expression patterns at five different grain developmental stages of Hongyingzi (an important brewing sorghum), and another two grain sorghums, Jinuoliang 1 and Hongliangfeng 1, for comparison. The uniquely expressed genes were identified at each developmental stage of Hongyingzi when compared with the other two sorghum cultivars. The co-regulated genes at different developmental stages and the regulatory network were determined; the determinant genes and single-nucleotide polymorphisms located at the promoters of these genes involved in starch and phenolic compounds biosynthetic pathways were also identified. These results will provide insights into the potential regulatory network and further contribute to the clarification of the key determinant genes involved in the biosyntheses of starch and phenolic compounds. Meanwhile, some new transcripts and genes were identified at five different developmental stages of grains of the three sorghum cultivars. Our work can provide impetus for further study of the genes responsible for the biosynthesis of starch and phenolic compounds in the sorghum grain, and pave a way for functional validation of a batch of potential genes and single-nucleotide polymorphisms proposed in current work.

Cytochrome P450 proteins belong to one of the largest families of enzyme proteins in plants and play important roles in plant growth and development and the stress response. In our previous studies, a cytochrome P450 gene, GhCYP94C1 (cytochrome P450 94C1), was functionally characterized as a positive regulator of seed germination, main root elongation and early flowering. However, whether the gene has other potential functions remains to be further explored. In our study, expression analysis showed that GhCYP94C1 was highly expressed in roots and was suppressed by drought treatment. Endogenous silencing of GhCYP94C1 via virus-induced gene silencing (VIGS) increased drought resistance in cotton plants, which was accompanied by the upregulated expression of the abscisic acid (ABA) biosynthesis gene nine-cis-epoxycarotenoid dioxygenase 9 (GhNCED9) during drought stress. Our findings suggested that GhCYP94C1 may play an important role in drought resistance. Combined with previous research results, the present results provide a theoretical basis for future breeding of new cotton varieties with early maturation and drought resistance.

Orange-fleshed sweetpotato (OFSP) is a sustainable and inexpensive source of vitamin A that contributes to food and nutritional security in developing countries. Its adoption is low due to unconformity of the variety with community food culture, limited cultivar selection and breeding studies. The current study aimed at breeding of promising OFSP genotypes in Benin using three parental lines. Two hundred and seventy-four seeds and one hundred and six genotypes were obtained through biparental crosses of Tio-joe (imported orange-fleshed variety), Vobodouaho (local white-fleshed variety) and ACAB220 (local orange-fleshed variety). The phenotypic diversity of genotypes was assessed using 10 leaf characters and storage root flesh colour through multiple correspondence analysis and hierarchical cluster analysis. The results indicated cross-compatibility between Tio-joe and ACAB220 when ACAB220 was used as female. Reciprocal cross-compatibility was found between ACAB220 and Vobodouaho. The genotypes could be separated into two main populations and classified into five cluster groups. Promising intermediate and pale orange genotypes were obtained indicating possibilities to incorporate beta-carotene into the white background of the Vobodouaho variety through further backcrossing.

To understand the cause of loss of rice blast resistance, we studied the pathogenicity of Magnaporthe oryzae strains isolated from rice hybrid Wuyou 308 and evaluated its resistance genes. A total of 62 M. oryzae strains were isolated and tested in 7 Chinese rice varieties with varying degrees of resistance to rice blast and 30 blast-resistant monogenic lines. Fourteen physiological races of M. oryzae were identified: 8.55% belonging to the ZA group, 86.67% to the ZB group, and 5.00% to the ZC group. ZB15 was the most abundant race (45.00%). Five resistance genes, Pi-3(1), Pi-z5, Pi-k, Pi-kp(C), and Pi-k(C), conferred good resistance to the 62 strains, with resistance frequencies of 95.56, 91.11, 88.89, 82.22, and 82.22%, respectively. In contrast, Pi-a(2) had a resistance frequency of 0%. The hybrid combination Wuyou 308 was found to carry Pi-ta and Pi-b genes. Because Pi-ta and Pi-b both showed low resistance frequencies to M. oryzae isolated from Jiangxi, the hybrid rice variety Wuyou 308 could be infected by most of the 62 M. oryzae strains. The emergence and spread of rice blast disease in Wuyou 308 may thus be difficult to avoid when climatic conditions are favourable.

Grain hardness is an important quality trait of cereals. In the present work, the particle size index (PSI) was used to assess the variability in grain hardness of thirteen triticale genotypes, three wheat genotypes and one rye genotype grown in two subsequent seasons. The PSI values of the triticale samples ranged between 7.7 to 19.2%, representing a medium hard to a very hard grain. Moreover, the sequencing of genes in the Hardness (Ha) locus revealed a limited genetic variability in the grain hardness genes, namely secaloindoline-a (Sina) and secaloindoline-b (Sinb). Two possible new allelic variants were identified, one for each of the secaloindoline genes. The existing variability in the grain hardness as well as polymorphisms in its candidate genes are a good starting point for efforts in breeding new varieties of triticale with improved grain hardness.

Cell wall digestibility is an important quality trait of modern silage maize cultivars. The symbiotic relationship between microbes and ruminant livestock enables the efficient upcycling of otherwise for human consumption unsuitable rumen digestible fibre or cell wall components into highly nutritious milk and meat. Before entering the Czech National List of Plant Varieties, new silage maize germplasm is extensively tested for different cell wall digestibility parameters. Recently published, the undigestible neutral detergent fibre (uNDF) cell wall digestibility approach promises even greater practical relevance. The aim of our study was, therefore, to assess the potential of the uNDF method, compared with current standard procedures, using a vast set of official Czech plant variety trial evaluations and Czech silage analyses from the 2018 cropping season. The uNDF method yielded a twice as high phenotypic standard deviation, compared with the current standard approaches. This is good news for plant breeders, official variety testing organisations, and farm professionals alike, enabeling faster variety improvement and simpler variety selection. On the other hand, due to the low differentiation potential, we discourage the use of the absolute lignin content when selecting for digestible silage maize varieties. Since between the digestibility traits enzymatic soluble organic substance (ELOS) and cellulase digestibility (DCS), a Pearson correlation close to one was observed, the substitution of one of these analytics by the uNDF method, may render valuable additional information in a highly economical manner.

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.

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.

Fusarium head blight (FHB) mainly caused by Fusarium species is one of the most important diseases threatening worldwide wheat production. To develop new FHB resistance resources, disease resistances of three new wheat lines L958, L962 and L987 were evaluated over a period of several years. We employed L699 (PI672540) and L661 as the resistant and susceptible control, respectively. Moderate FHB resistance was observed in these three wheat lines, among which the genotype L958 was found a good resource for yield, quality and FHB resistance improvement. In addition, genotype L962 was found to be resistant to powdery mildew, and both L958 and L987 carried the YrL693 gene conferring stripe rust resistance. The study provides promising results for accelerating the resistance breeding of the three wheat lines.

This study presents the first report comparing the efficiency of microspore culture, gynogenesis and durum wheat × maize crosses for haploid plant production from three durum wheat genotypes (Razzek, Karim and Jneh Khotifa). The results showed that the best induction, calli or embryos formation and plant regeneration rates for the three genotypes were obtained with gynogenesis (47.2, 7.6, 0.8%), followed by interspecific crosses (33.1, 1.7, 0.4%) and isolated microspore culture (8.2, 0.05, 0.01%). Interestingly, all plants regenerated by gynogenesis and durum wheat × maize crosses were green whereas all plants obtained by isolated microspore culture were albino. In the haploid production system, all steps of the process are important for the three methods. The critical steps that have greatly reduced the number of regenerated haploid plants were induction, embryogenesis and regeneration for microspore culture, forming and regeneration of calli or embryo and haploid regeneration for interspecific crosses and gynogenesis. Genotypes with good capacity of induction have not necessarily a good capacity of haploid plantlets regeneration and vice-versa. However, calli or embryos formation seems to be an indicator of the haploid production. Overall, Razzek showed a good ability to produce haploids using the three methods. Each haplomethod showed a specific advantage. Although gynogenesis is the less used method for durum wheat, it has proved to be a successful approach for green haploid plant production.

Cotyledons of 201 microspore-derived oilseed rape (Brassica napus) embryos were analysed for the presence of the cytoplasmic male sterility Shaan 2A restorer gene using the primer pair 3F/4R. In total, 172 plants regenerated and were grown to the generative stage. Among phenotypically non-haploid flowering plants, there was a broad spectrum of different flower types from normally developed flowers to flowers with short anthers, stamens, or deformed flowers with atypically developed floral organs, often with traces of pollen. For this reason, only 115 typically fertile or sterile accessions were selected for further phenotype-genotype comparisons. In 14 plants (12.2%) the phenotype did not match the genotype: two plants were marked as fertile, but without the Rf gene. Vice versa, in 12 sterile plants the Rf gene was determined. Nevertheless, the two fertile plants did not produce any pods after self-pollination. In total, 47 doubled haploid (DH) lines with good seed yield, carrying the Rf gene were harvested.

Genetic variation within and among fifteen Trifolium species represented by 157 accessions was assessed using morphological and isozyme markers. Most of morphometric characters contributed to the discrimination of the species. No significant relationship between the environment of the collection site and morphological features was detected. The two isozyme systems analysed, esterase (EST) and glutamate oxaloacetate transaminase (GOT), proved polymorphic. Phenotype diversity of isozyme markers ranged from 0.07 to 0.61 with an average of 0.31 based on the polymorphic information content. The pairwise Jaccard's similarity coefficient ranged between 0.10 and 0.60, indicating that the collection represents genetically diverse species. A considerable number of species-specific zymograms were detected which can be used for the species identification. The clustering pattern of isozyme markers was incongruent with the groupings based on quantitative traits. The rich isozyme variability present among the Algerian clover species indicates that they can provide good gene resources for breeding.

Changes in the gene pool and homogeneity of red clover cultivars occur over time. Therefore, it is necessary to constantly renew the breeding material and foundation seed. Moreover, the market also prescribes a new demand. Based on the Natura 2000 habitats profile, we collected seeds from 39 locations across Lithuania in 2016. The phenotypic traits that affect the seed yield of red clover were analysed in 2018. The homogeneity of the populations with reference to the seed yield and 1 000 seed weight (TSW) were determined as well. Also, the possibility of obtaining two seed yields per season under drought conditions from wild genotypes of red clover was analysed. We found that the final seed yield mostly depends on the seed number per flower head (SN/FH), which strongly correlated with 1^st component of PCA during first (r = 0.91) and second (0.92) harvest. Meanwhile, the cluster analysis showed that the typical wild red clover has a lower seed weight than the cultivars and could be clustered on the basis of seed homogeneity. Finally, based on the seed phenotype and harvest components, there were five prospective accessions (2177, 2871, 2876, 2898 and 2899) for a new cultivar prototype.

Grapevine is a worldwide crop and it is also subject to global trade in wine, berries and grape vine plants. Various countries, including the countries of the European Union, emphasize the role of product origin designation and suitable methods are sought, able to capture distinct origins. One of the biological matrices that can theoretically be driven by individual vineyards' conditions represents DNA methylation. Despite this interesting hypothesis, there is a lack of respective information. The aim of this work is to examine whether DNA methylation can be used to relate a sample to a given vineyard and to access a relationship between a DNA methylation pattern and different geographical origin of analysed samples. For this purpose, DNA methylation landscapes of samples from completely different climatic conditions presented by the Czech Republic (Central Europe) and Armenia (Southern Caucasus) were compared. Results of the Methylation Sensitive Amplified Polymorphism method confirm uniqueness of DNA methylation landscape for individual vineyards. Factually, DNA methylation diversity within vineyards of Merlot and Pinot Noir cultivars represent only 16% and 14% of the overall diversity registered for individual cultivars. On the contrary, different geographical location of the Czech and Armenian vineyards was identified as the strongest factor affecting diversity in DNA methylation landscapes (79.9% and 70.7% for Merlot and Pinot Noir plants, respectively).

Leaf rust, caused by Puccinia triticina, is a major wheat disease worldwide. The chinese wheat cultivar L224-3 showed high resistance to most of P. triticina pathotypes in the seedling and adult stage. Identifying and mapping the leaf rust resistance gene(s) in L224-3 is very useful for breeding leaf rust resistant wheat cultivars. In the present study, the wheat cultivar L224-3 and thirty-six lines with known leaf rust resistance genes were inoculated with 15 pathotypes at the seedling stage for gene postulation. A total of 144 F_2:3 lines from the cross L224-3 × Zhengzhou 5389 were inoculated with the pathotype FHBQ for leaf rust genetic analysis at the seedling stage. A total of 1276 SSR (simple sequence repeat) markers and the STS (sequence tagged-site) marker ω-secali/Glu-B3 were used to test the parents, resistant and susceptible bulks. The polymorphic markers were used to genotype the F_2:3 populations. L224-3 was highly resistant to all Lr26 avirulent pathotypes, showing the presence of Lr26 in L224-3. The presence of Lr26 in L224-3 was also confirmed by the molecular marker ω-secalin/Glu-B3. Due to resistance to some Lr26 virulent pathotypes, L224-3 may carry another resistance gene. Based on the genetic analysis using the pathotype FHBQ with virulence to Lr26 the resistance of L224-3 was controlled by a single dominant gene, tentatively designated LrL224. Four SSR markers (barc8, gwm582, wmc419, and wmc694) and one STS marker (ω-secali/Glu-B3) on 1B were closely linked to LrL224. The two flanking SSR loci were barc8 and gwm582, with the genetic distances of 4.3 and 4.6 cM, respectively. LrL224 was located on 1BL, and it showed different seedling reactions with other genes on 1B. Therefore LrL224 is likely to be a new leaf rust resistance gene.

Combining ability analysis was performed in order to identify high-yielding genotypes and hybrids. Six lines were crossed with three testers using a line × tester mating design. General combining ability (GCA) of parents, specific combining ability (SCA) of hybrids and gene action for several yield components and fibre were studied in the experiment. Additive gene action was observed in most traits except bolls/plant, sympodia/plant, monopodia/plant, total nodes, seed index, lint/seed, staple strength and seed cotton yield/plant which were influenced by non-additive gene action. GCA revealed that Giza-7 was a good general combiner for staple length, staple strength, seed index, boll weight, bolls/plant and monopodia/plant and BH-167 was good for ginning outturn (GOT) and sympodia/plant. Results of SCA values for hybrids indicated, that the cross Giza-7 × MNH-886 was a superior specific combiner for staple length, monopodia/plant, staple strength and seed cotton yield/plant; CIM-554 × CIM-557 for boll weight, sympodia/plant and lint weight/boll; BH-167 × MNH-886 for GOT and bolls/plant. Selection of such hybrids and good general combiners could be further exploited for yield improvement.

Genetic linkage maps representing the tobacco genome have been an important tool for breeding programs because of the elucidation of polygenic traits. We constructed a genetic linkage map of cigar tobacco (Nicotiana tabacum L.) based on an inter-type backcross population of 213 individuals and performed a comparative analysis with other published maps of dark tobacco and flue-cured tobacco. The map consisted of 562 SSR loci distributed on 24 tentative linkage groups and spanned a total length of 1341.18 cM with an average distance of 2.39 cM between adjacent markers. The comparative analysis revealed a Spearman correlation index of 0.93 for marker order conservation with the previously published maps constructed for different tobacco types. Approximately 91% of the SSR markers common to other inter-type maps were located in the same positions as in previous maps. The three maps exhibit good synteny in terms of the shared markers, which suggests that there might be no translocation variations between the genomes of the cigar, dark and flue-cured tobaccos. These results indicate the feasibility of generating a unique genetic map of preferred traits in cigar tobacco and that such mapping may be helpful for breeding programs because plants derived from different inter-type populations can be rapidly scanned using the markers associated with useful cigar traits

Copalyl diphosphate synthase 1 (SmCPS1) is the first committed enzyme in tanshinone biosynthesis. The promoter region plays an important role in the transcriptional regulation of genes. Mutations in the promoter region may affect gene expression, resulting in changes in the amount of metabolites. In this study, we investigated the SmCPS1 gene promoter region together with the 388 bp downstream from the translation start site and the content of tanshinones of 12 different genotypes of Salvia miltiorrhiza. The cis-elements of SmCPS1 promoter were predicted and analysed by the Plant Transcriptional Regulatory Map database. We found (1) a different correlation between the polymorphism in the promoter region and the contents of tanshinones; (2) functional polymorphic loci - four tandem repeat variations, three indels and five single nucleotide polymorphisms (SNPs) in five cis-elements, three SNPs in exons and two SNPs in introns; (3) the correlation coefficient was higher when only functional (informative) polymorphic loci were considered. These findings have laid the foundation for further exploring the interspecific variation of S. miltiorrhiza and its relationship with the contents of tanshinones.

In vitro meristem cultures have been used for the production of hop (Humulus lupulus L.) virus-free rootstocks worldwide, because multipropagation is considered to preserve the genetic stability of the produced plantlet. Nevertheless, in vitro tissue cultures can cause genetic and epigenetic changes. Therefore, we studied the genetic and epigenetic variability of Saaz Osvald's clones, Sládek and Premiant cultivars on the DNA methylation level by methylation-sensitive amplification polymorphism (MSAP). In vitro propagated plants, acclimatised glasshouse rootstocks as well as derived mericlones and control plants under field conditions were used for the analyses. A total of 346 clearly and highly reproducible amplified products were detected in the MSAP analyses within the studied hop plants. We found 16 polymorphic products (4.6% of products) and 64 products with methylation changes (18.5% of products) in the analyses. The demethylation events were comparable to the de novo methylation events. Most demethylation changes were found in the in vitro plants, but only a few of them were found in the derived mericlones under field conditions. In contrast, the de novo methylation changes persisted in the acclimatised plants under glasshouse or field conditions. A hierarchical cluster analysis was used for the evaluation of the molecular genetic variability within the individual samples. The dendrogram showed that the individual samples of the same variety, more or less, clustered together. Because the methylation status varied during the virus-free rootstock production process, we suppose that de/methylation process is a natural tool of epigenetics and evolution in vegetatively propagated plants.

Intercropping of grain legumes and cereals is a promising theme in organic farming for its potential for increasing and stabilizing yields, reducing weed pressure and sustaining plant health. On animal husbandry farms, pea-cereal mixtures may be an interesting crop harvested for green fodder as well as for feed concentrates. Increasing self-sufficiency with fodder is in agreement with the principles of organic agriculture, and it reduces the risks related to the import of soy protein that may be admixed with GM soya. In 2008-2011, plot trials (PT) with intercropped peas and spring cereals (wheat, barley) were conducted. Varieties and pea-cereal combinations were examined to find suitable varieties for intercropping, and the best pea to cereal ratio in the seed intercrop (pea to cereal ratios 80:20, 60:40, 40:60, 20:80). Results show that intercropping peas and spring cereals may be advantageous compared to monocultures. Pea-cereal intercrops produce high yields of green matter and concentrates especially when intercropped at the pea to cereal ratio of 60:40 and 40:60. In 2009, on five certified organic farms, controlled field trials (FT) were conducted with field pea (leaf type), spring barley and spring wheat in monocultures and intercrops (pea to cereal ratio 60:40). Forage yields were evaluated at pea growth phases BBCH-scale 79 and 83. Fresh yields of monocultures and intercrops were evaluated at grain harvest.

The wheat cultivar Weimai 8 is a good source of adult-plant resistance to leaf rust in China. In order to understand the genetic background of the resistance genes, 179 F2:3 families derived from the cross Weimai 8 and Zhengzhou 5389 (susceptible to leaf rust) were used to construct a linkage map. Results showed that there was a major QTL on chromosome 2AS, temporarily named QLr.hbau-2AS, responsible for the resistance. QLr.hbau-2AS from the resistant parent Weimai 8 was between the SSR markers Xcfd36 and Xbarc1138, with an interval length of 2.58 cM. In the 2010-2011, 2011-2012 and 2012-2013 crop seasons, it explained 25.79, 71.55 and 60.72% of the phenotypic variation, respectively. The location of QLr.hbau-2AS was close to the leaf rust resistance gene Lr37. However, they may not be the same since QLr.hbau-2AS has a different virulence test response from Lr37. This study identified two closely linked flanking molecular markers QLr.hbau-2AS and these molecular markers will help marker-assisted selection in breeding resistant cultivars in the future.

Planting grasses that require low maintenance is a good option for reducing the management input required. The objective of this study was to obtain information about turfgrass characteristics based on spaced-plant characterization and turf performance in turf plots of two selections (Paula hard fescue and Casero colonial bentgrass) recently released for public distribution by the Plant Production Area of the University of Oviedo. The plants were grown under conditions of no irrigation, no fertilizer, no pesticide application and minimal mowing over a 3-year period (2012-2014). The following morphological measurements were done in a spaced-plant nursery: heading date, plant height, inflorescence length and flag leaf length and width. The turf plots were evaluated for several traits including overall turfgrass quality (turf score), leaf texture and genetic colour. In both the spaced-plant nursery and turf trials, hard fescue genotypes displayed better morphological characteristics (narrow leaves, reduced plant height) and performed better (overall high turfgrass quality, fine leaf texture, dark green colour) than bentgrass genotypes under conditions of low maintenance. For areas in which climate, soil characteristics and management conditions are similar to those encountered in this trial, the selection of Paula hard fescue is recommended for use in low-maintenance turf settings because of the good turfgrass performance and morphological characteristics of this selection.