Barley Leaf Stripe Research Articles

Pgmiox mediates stress response and plays a critical role for pathogenicity in Pyrenophora graminea，the agent of barley leaf stripe

Barley leaf stripe is an important disease caused by Pyenophora graminea that affects barley yields in the world. Ascorbic acid (AsA) interacts with key elements of a complex network orchestrating plant defense mechanisms, thereby influencing the outcome of plant-pathogen interaction. Myo-inositol oxygenase (MIOX) is a pivotal enzyme involved in plants development and environmental stimuli. However, MIOX has described functions in plants but has not been characterized in fungi. In this study, we characterized the Pgmiox gene in P. graminea pathogenesis through annotated on the metabolic pathway of ascorbic acid aldehyde. Our analysis suggested that the Pgmiox protein had a typical conserved MIOX domain. Multiple alignment analysis indicated that the P. graminea MIOX orthologue clustered with MIOX proteins of Pyrenophora species. RNA interference successfully reduced transcript abundance of Pgmiox in six transformant lines compared to wild type, and the transformants were further less virulent on the host plant barley. Transformants of Pgmiox had significant reductions in vegetative growth and pathogenicity, which had increased resistance to tebuconazole and carbendazim. In addition, Pgmiox is associated with ionic, drought, osmotic, oxidative, and heavy metal stress tolerance in P. graminea. In conclusion, our findings reveal that Pgmiox may be widely utilized by fungi to enhance pathogenesis and holds significant potential for the development of durable P. graminea resistance through genetic modifications.

Detection of some registered barley varieties reactions to barley leaf stripe disease

Cereals are a significant agricultural product group with the highest cultivation area and production in Turkey. Among these cereals, barley is an important cereal used in human and animal nutrition, and the most widelycultivated plant after wheat. There are biotic and abiotic factors which affect the yield and quality parameters of barley. Of the biotic factors, barley leaf stripe (agent: Pyrenophora graminea (anamorph: Drechslera graminea) is an important fungal disease. Infections can occur in diseased seeds and in the presence of suitable environmental conditions. Hence, the use of disease-free seeds and resistant cultivars (cvs.) against this pathogen are crucial. With this in mind, this study was carried out with a highly virulent isolate of Pyrenophora graminea, obtained from the Disease and Pest Resistance Unit culture collection in 57 registered barley cultivars in the greenhouses of the Central Research Institute of Field Crops (TARM) in 2021. The experiments were conducted in 3 replications in a randomized block design. Of 57 registered barley cultivars 62%, 15% and 36% of these barley cultivars expressed resistance, moderate resistance, and susceptible reactions, respectively. As a result of the analysis of variance performed on the results obtained, it was concluded that the difference between the mean values of 57 varieties was statistically significant at 1% level (P

Development of Loop-Mediated Isothermal Amplification Assay for the Rapid Detection of Pyrenophora graminea in Barley Seeds

Barley leaf stripe, caused by Pyrenophora graminea, is an essential systemic seed-borne disease in barley worldwide. Barley is a major cereal crop in the Qinghai–Tibet Plateau, and barley production has been threatened by leaf stripe in this region, particularly in organic farming regions. Detecting the pathogen in infected barley seeds is crucial for managing barley leaf stripe. In this study, a loop-mediated isothermal amplification (LAMP) assay was developed to detect the pathogen based on primers designed based on the sequence of the pig 14 gene (GenBank: AJ277800) of P. graminea. The optimal concentrations of MgSO4, dNTPs, and enzymes in the LAMP reaction system were established as 10.0 mM, 1.0 mM, and 8 U in a 25 μL reaction volume, respectively. The established LAMP methods for detecting P. graminea were optimally performed at 63 °C for 70 min with high reliability. The minimum detection limit was 1 × 10−2 ng·μL−1 in the 25 μL reaction system. The specificity of LAMP for P. graminea was validated with eight fungal species. All DNA extracts from P. graminea-infected barley seeds with incubation, intact, and smashed treatments were applied in LAMP and confirmed to enable the detection of the pathogen. The LAMP assay in this study could facilitate the detection of P. graminea in barley seeds onsite, provide information for seed health certificates, and help decide on seed treatment in leaf stripe management.

Comparative study of Pyrenophora graminea incidence on Hordeum vulgare L. hybrid populations and their parents.

The seed- borne pathogen Pyrenophora graminea Ito& Kur. is the causal agent of barley leaf stripe, a destructive disease in most barley growing region in the world. In order to improve the barley species in Algeria against this disease, it is necessary to know their tolerance reaction to it. The genotype that have been tested are five parent genotypes: ACSAD, Tichedrett, Saida, Rihane, Hamra and eight populations hybrid obtained by intraspecific crosses of the parents and then sowing of F1 to F8. We compared the incidence of the isolate of Pyrenophora graminea for morphological characters (Stem height) and yield (1000-grain weight, medium yield of plant) of the studied variety. The results obtained showed the existence of variability between our thirteen genotypes of barley which had a different resistance level in the quantitative and qualitative characters.

Use of gene family analysis to discover argonaut (AGO) genes for increasing the resistance of Tibetan hull-less barley to leaf stripe disease

Leaf stripe is a common, but major infectious disease of barley, severely affecting the yield and quality. However, only a few genes have been identified by conventional gene mapping. Gene family analysis has become a fast and efficient strategy for gene discovery. Studies demonstrated that Argonaute (AGO) proteins play an important role in plant disease resistance. Thus, we obtained nine HvAGO genes via mRNA sequencing before and after a Pyrenophora graminea infection of a disease-resistant variety "Kunlun 14" and a susceptible variety "Z1141". We analysed the physicochemical characteristics, gene structures, and motifs of the HvAGO gene sequences and found that these proteins were divided into four clusters by evolutionary distance. There was high consistency in the number of exons, size, and the number and type of motifs in the different clusters. Based on protein phylogenetics, they could be divided into three branches. A collinearity analysis of Tibetan hull-less barley and Arabidopsis thaliana, rice, and maize showed that four genes were collinear with respect to the other three species. The qRT-PCR showed the expression levels of HvAGO1, HvAGO2 and HvAGO4 were significantly increased after infection with Pyrenophora graminea. These three members of the AGO gene family are, thus, speculated to play an important role in barley leaf stripe resistance. The results provide reference for the application of HvAGO genes in the leaf stripe control and the exploration of disease resistance genes in other crops.

Identification microRNAs and target genes in Tibetan hulless barley to BLS infection

AbstractTibetan hulless barley (Hordeum vulgare L. variety nudum Hook. f.) is widely grown on the Qinghai‐Tibet Plateau, where it has served as a staple food for Tibetan people since the 5th century CE. Barley leaf stripe (BLS) is one of the most severe fungal diseases affecting the yield and quality of Tibetan hulless barley. Here, we compared the miRNA profiles before and after BLS in a BLS‐sensitive (‘Z1141’) and tolerant (‘Kunlun14’) Tibetan hulless barley for the first time. A total of 36 conserved and 56 novel miRNAs were identified, of which 24 differentially expressed miRNAs were found in Z1141 and Kunlun14, and an additional 546 putative target genes were predicted. Transcriptome sequencing analysis showed that among these genes, 131 were differentially expressed in normal and infected leaves of Kunlun14 and Z1141. Gene ontology (GO), pathway, and Blast analyses indicated 10 candidate target genes including seven functional genes and three transcription factors were involved in barley disease resistance. These functional genes were two members of the CYP450 genes, a RGA gene, a LIN gene, a SAM gene, a PSD gene, and a NDB gene; the three transcription factor genes were all from the WRKY family. These 10 candidate target genes were regulated by eight miRNAs (hvu‐miR168‐3p, hvu‐miR171‐5p, hvu‐miR159b, hvu‐miR156a, hvu‐novel‐91, hvu‐novel‐46, hvu‐novel‐52, and hvu‐novel‐11). According to quantitative real‐time polymerase chain reaction (PCR) results, the 10 targets were negatively correlated with their corresponding miRNAs after infection with BLS. Thus, these miRNAs and their target genes can be used to improve BLS resistance in Tibetan hulless barley though breeding programs or genetic engineering.

Resistance of European Spring 2-Row Barley Cultivars to Pyrenophora graminea and Detection of Associated Loci

Pyrenophora graminea is the seed-borne pathogen causal agent of barley leaf stripe disease. In this work, we screened a collection of 206 spring two-row barley cultivars from Europe for their resistance to the fungal pathogen. Artificial inoculation with the highly virulent isolate Dg2 revealed a continuous variation for the incidence of infection, with few highly resistant or highly susceptible genotypes. On average, old cultivars showed higher resistance than the more modern ones. Genome-Wide Association Scan was performed by exploiting available molecular data for >4000 SNP markers and revealed a single, highly significant association on the short arm of chromosome 6H, in a genomic position where quantitative trait loci (QTL) for barley resistance to P. graminea were not detected before. Based on the last version of the reference barley genome, genes encoding for proteins with a kinase domain were suggested as candidates for the locus.

Pathogenic organisms on spring barley in the eastern forest-steppe of Ukraine

Purpose. To detect harmful organisms on spring barley and their variability under the influence of hydrothermal conditions during the crop vegetation period in the Eastern Forest-Steppe of Ukraine and to improve methods of pathogen detecting on plants and grains.Material and methods. The prevalence of diseases and pests was determined by conventional and special methods in accordance with the existing assessment scales and by methods modified by us in the course of work. We improved methods for determining pathogenic species on spring barley upon spring (optimal) and autumn (simulation of wet conditions) sowing followed by evaluating the disease signs during the tillering phase of plants and selecting nutrient medium for phytoexamination of grain and assessment of its infection rate.Results and discussion. The 2009–2020 assessments of the prevalence of diseases and pests on spring barley plants from seeds sown on different dates (autumn and spring) showed that the autumn sowing was more effective for barley net blotch manifestation on spring barley compared to the conventional method of spring sowing, since the autumn conditions are favorable for development of this fungus. Pathogens on spring barley were mainly represented by head smut (Ustilago hordei), barley leaf stripe disease, root rots and corn flies. The greatest prevalence of head smut (up to 67.0%) was observed in the years when the weather was excessively humid during the growing period (HTC =1.7 in 2020) or slightly arid (HTC =1.1 in 2015). The greatest spread of barley net blotch (100%) was observed on sufficient water supply in 2014 (HTC = 1.4). The numbers of frit flies during the study period were significant (up to 100%), only in 2016 there was a decline to 39%. The pathogen species that develop on spring barley seeds were determined. Alternaria contamination of grain ranged 9.0 to 77.0% from year to year; Drechslera contamination - 4.0 to 55.0%, Fusarium contamination - 0.0 to 12.4%.Conclusions. Head smut (Ustilago hordei (Pers. Lagerh.)) and Drechslera fungi causing leaf blotch and root rot (Drechslera teres Ito, D. graminea (Rabenh.) Shoemaker, D. sorokiniana Subram) were found to be the most common diseases of spring barley in the Eastern Forest-Steppe of Ukraine. Of pests, frit flies (Oscinella frit Linnaeus and O. pusilla Meigen) were most common. Major diseases of spring barley seeds are of fungal etiology (genera Drechslera spp., Fusarium Link. and Altenararia Fries). Two new methods of phytopathological analysis of the prevalence of diseases on spring barley crops have been developed: one of them is carried out by autumn sowing of seeds and evaluating plant damage during the tillering phase; the second method is phytoexamination of seeds for pathogens via germination of caryopses in sucrose solution

Efficacy of Some Fungicides, Commercial Plant Oils and Bio-Agents against Drechslera Graminea Inciting Barley Leaf Stripe Disease

The antifungal activity of 5 fungicides, 3 commercial plant oils and 2 bio-agents were tested in vitro and in vivo against Drechslera graminea (Rabenh. ex. Schlech) Shoemaker (telemorph: Pyrenophora graminea Ito and Kuribayashi, the causal organism of leaf stripe disease on barley (Hordeum vulgare L.). Among fungicides tested, Opus at 1µl/L and Switch at 1mg/L concentration and Bellis at 2mg/L showed 100% mycelia growth inhibition of D. graminea. The results of commercial plant oils tested in vitro revealed that the coriander showed highest inhibition of mycelial growth at 15%. The dual culture technique revealed that fungal bio-agent (Trichoderma harzianum) was better than bacterial bio-agent (Bacillus subtilis) in inhibiting the growth of D. graminea. Greenhouse and field experiments were carried out to evaluate the efficacy of all tested treatments on disease incidence, yield components, enzymes activity and phenolic compounds. The tested fungicides, plant oils and bio-agents applied as seed dressing showed an effectiveness to large extent for controlling leaf stripe disease expressed as a reduction in disease incidence and increased yield components in comparing with the untreated plants. As well as, the all treatments caused an increment in activities of peroxidaxe, polyphenol oxidase and chitinase enzymes and increasing in phenolic compounds compared to control treatment. Although the five tested fungicides were more effective in reducing the linear growth of the pathogen (D. graminea) in vitro and suppressing the disease in vivo than the plant oils and bio-agents, they are considered environmentally safe and can be used as alternative substances in disease management.

Characterization of barley germplasm for leaf stripe (Pyrenophora graminea) resistance based on incidence and severity parameters

Barley leaf stripe (BLS) caused by Pyrenophora graminea is an important seed-borne disease of barley causing significant yield and quality losses worldwide. The development of resistant cultivars has proven difficult, therefore, in this work, BLSresistant barley germplasm was developed by crossing six barley cultivars currently used in Europe and West Asia. Out of 270 doubled haploid lines derived from these crosses, 40 lines were evaluated under field artificial infection conditions using incidence (I; proportion of diseased plants) and severity (S; proportion of infected leaf area per plant). Disease resistance parameters showed a broad range of variation in mean I and S values with a continuum of resistance levels ranging from highly susceptible to highly resistant with values being consistently higher in the susceptible ones. However, eight promising resistant lines with high yield per plant were identified. Moreover, BLS severity increased linearly as incidence increased (r = 0.76, P < 0.001). This work suggests that BLS resistance sources identified in this study can be used for further genetic analysis and introgression for varietal improvement, and that the positive correlation between I and S parameters may be beneficial for many types of studies on this disease.

Genome Resource for Barley Leaf Stripe Pathogen Pyrenophora graminea

Pyrenophora graminea is the causative agent of barley leaf stripe disease. In this study, the strong pathogenic isolate QWC was used to generate DNA for Illumina sequencing. After assembly, its genome size was 42.5 Mb, consisting of 264 scaffolds, and a total of 10,376 genes was predicted. This is the first genome resource available for P. graminea. The genome sequences of P. graminea will accelerate the understanding interaction of P. graminea and barley.

Distribution of mating type alleles in Iranian populations of Pyrenophora graminea, the causal agent of barley leaf stripe disease, using a multiplex PCR approach

Pyrenophora graminea is the main fungal species associated with barley leaf stripe disease worldwide. Even though a heterothallic mating strategy has been proven for P. graminea, this species is mainly known based on the asexual morph in nature and there is no available information on the prevalence of an active sexual cycle within the populations of this species in Iran as well as many other barley-producing countries. The feasibility of a cryptic sexual cycle within Iranian isolates of P. graminea was assessed through analyzing the distribution and frequency of the mating type alleles on micro-spatial and macro-geographical scales. A total number of 306 P. graminea isolates were obtained from 93 fields in 45 geographical regions across East Azerbaijan province during 2016–2017. A multiplex PCR assay was developed for simultaneous identification of P. graminea and screening of its mating type alleles using previously designed primer sets. Using the multiplex PCR assay, a 435-bp band was consistently amplified from all P. graminea isolates; while a 1300-bp fragment or a 1150-bp fragment was only amplified from the isolates harboring MAT-1 and MAT-2 alleles, respectively. The mating type identity of 164 isolates was determined as MAT-1 and 142 isolates as MAT-2. Results of the present study revealed a nearly equal distribution (1:1 ratio; X2=1.582) of mating type alleles within and between different populations of P. graminea. Results of the micro-spatial and macro-geographical distribution of mating types showed that both mating types were often present on almost all studied scales, including: within the same lesion of each leaf from a single barley plant, from the same field or different fields in the same region, and from different regions. Based on the results of the current study and referring to the earlier reports on the population structure of P. graminea, it is concluded that this pathogen undergoes regular cycles of sexual recombination in most of the examined regions.

Barley Leaf Stripe Disease in Algeria: Evaluation of Virulent Pyrenophora graminea Isolates and Identification of Resistant Algerian Barley Genotypes

Nine isolates of Pyrenophora graminea, barley leaf stripe disease causal agent, collected from several regions in Algeria were evaluated under greenhouse conditions for their virulence to a collection of barley cultivars including three most cultivated Algerian varieties. Virulence levels were observed among the set of isolates and a mean disease rate ranging from 3.33% to 75.83% was found. Pathogenic variability of P. graminea and resistant gene effects in barley cultivars were revealed. Isolate OS was the most virulent among P. graminea isolates making it a suitable virulent isolate in future breeding programs. A set of 8 barley genotypes composed of common Algerian cultivars and local developed lines were tested for their reaction to P. graminea and yield response. Barley cultivar Minnesota 23 and line 18/17/7L2 were the most resistant of the collection with high grain number/ear and thousand grains weight even when diseased. These genotypes could be useful to integrate as candidate genitor plants into barley breeding programs to develop resistant cultivars to leaf stripe disease.

PGPBS, a mitogen-activated protein kinase kinase, is required for vegetative differentiation, cell wall integrity, and pathogenicity of the barley leaf stripe fungus Pyrenophora graminea

The high-osmolarity glycerol (HOG) signaling pathway regulates the adaptation of fungi to environmental stressors. The mitogen-activated protein kinase kinase (MAPKK) PBS2 of Saccharomyces cerevisiae serves as a scaffold protein in the HOG pathway. We characterized the pgpbs gene of Pyrenophora graminea, which encodes a MAPKK that is 56% orthologous to PBS2 of S. cerevisiae. A cloning technique based on homology was applied to amplify the pgpbs gene. Specific silent mutations then were generated in pgpbs. We evaluated the potential roles of PGPBS in the osmotic response, vegetative differentiation, cell wall integrity, drug resistance, and pathogenicity. Our findings indicated that the pgpbs coding region comprises 2075 base pairs and encodes a protein of 676 amino acids. Mutants deficient in pgpbs expression had significant reductions in vegetative growth and were sensitive to calcofluor white (CFW), an inhibitor of cell wall synthesis. Mutants also lost pathogenicity and were sensitive to an osmotic stress–inducing medium containing NaCl and sorbitol. Moreover, mutants had increased resistance to the dicarboximide fungicide iprodione and the triazole fungicide tebuconazole. These findings suggest that pgpbs is involved in the osmotic and ionic stress responses, vegetative differentiation, cell wall integrity, virulence, and tolerance to iprodione and tebuconazole. We expect that our findings will help elucidate the pathogenesis of barley leaf stripe and will inform strategies for breeding resistance to this disease.

Development and characterization of microsatellite markers based on whole-genome sequences and pathogenicity differentiation of Pyrenophora graminea, the causative agent of barley leaf stripe

Barley leaf stripe, caused by the fungal pathogen Pyrenophora graminea, is becoming a destructive disease in the Hexi corridor of the Gansu province (China). Knowledge of the genetic diversity, population structure, and specific pathogenicity of P. graminea is essential for barley resistance breeding and efficient control of leaf stripe. In this study, whole-genome sequences of P. graminea were applied to identify microsatellites and develop simple sequence repeat (SSR) markers. These SSR markers were used to examine the genetic diversity and population structure of barley leaf stripe fungus in China. A total of 403 SSR primers were designed and synthesized, and target fragments were amplified by 390 microsatellite markers. These fragments corresponded to 789 alleles (1–5 alleles per locus) in eight strains (average, 2.02 alleles per marker locus). The cluster analysis and population structure were analyzed by means of 100 markers, and a total of 696 alleles were detected from 44 accessions (mean, 6.96 alleles per marker; range, 3–17). The average gene diversity was 0.63, and ranged from 0.11 to 0.92. The polymorphism information content (PIC) ranged from 0.11 to 0.91 with an average of 0.59. The Shannon’s Information Index ranged from 0.29 (for Pgm254 and Pgm337) to 2.64 (for Pgm371), with an average of 1.36. Results of cluster analysis showed that 44 accessions were divided into four clusters. Overall, 44 strains were divided into three subpopulations, comprising 19, 17, and eight strains each. Six isolates were tested for pathogenicity differentiation on 10 barley cultivars. Cultivar Ganpi2 was found to be resistant to all six isolates; nine of 10 cultivars had varied reactions to six isolates. Genome sequencing of P. graminea enabled SSR marker development, and SSR markers are applicable to studies of population genetic structure in P. graminea. We conclude that pathogenicity differentiation exists among the six isolates in the study.

Effect of several rhizobacteria strains on barley resistance againstPyrenophora gramineaunder field conditions

SummaryThe effect ofPseudomonas putidaBTP1,Bacillus subtilisBs2500, Bs2504, and Bs2508 strains on the incidence (I) and severity (S) of barley leaf stripe disease caused byPyrenophora gramineawas evaluated under field conditions. Three barley cultivars varying in resistance level were used. The resistance achieved in our study was long-lasting.P. putidaBTP1 and Bs2508 were in general the most effective strains in reducing significantly both I and S of barley leaf stripe disease vis-a-vis three cultivars in two growing seasons 2013/2014. The disease was reduced up to 66% in Arabi Abiad treated withP. putidaBTP1. The susceptible landrace cultivar Arabi Abiad exhibited a significant induction of resistance by Bs2508 and BTP1. However, the resistant cultivar Banteng did not exhibit significant further increase in resistance by these bacterial strains. The grain yield of bacterized plants artificially inoculated withP. gramineawas not affected, except that of the cultivar Arabi Abiad treated with Bs2508 and Bs2504. Triggering of resistance by treating seeds with the bacterial strains would be of great value in agriculture, especially in case of barley infection byP. gramineaat an early stage of plant development.

Deciphering the transcriptional regulation and spatiotemporal distribution of immunity response in barley to Pyrenophora graminea fungal invasion.

BackgroundBarley leaf stripe disease, caused by the fungus Pyrenophora graminea (Pg), is a worldwide crop disease that results in significant loss of barley yield. The purpose of the present work was to use transcriptomic profiling to highlight barley genes and metabolic pathways affected or altered in response to Pg infection and consequently elucidate their involvement and contribution in resistance to leaf stripe.ResultsOur study examined and compared the transcriptomes of two barley genotypes using an established differential display reverse-transcription polymerase chain reaction (DDRT-PCR) strategy at 14 and 20 days post-inoculation (dpi). A total of 54 significantly modulated expressed sequence tags (ESTs) were identified. The analysis of gene expression changes during the course of infection with Pg suggested the involvement of 15 upregulated genes during the immunity response. By using network-based analyses, we could establish a significant correlation between genes expressed in response to Pg invasion. Microscopic analysis and quantitative PCR (qPCR) profiling of callose synthase and cellulose synthases revealed a direct involvement of cell wall reinforcement and callose deposition in the Pg-resistant phenotype.ConclusionsWe have identified a number of candidate genes possibly involved in the host-pathogen interactions between barley and Pg fungus, 15 of which are specifically expressed in Pg-resistant plants. Collectively, our results suggest that the resistance to leaf stripe in barley proceeds through callose deposition and different oxidation processes.Electronic supplementary materialThe online version of this article (doi:10.1186/s12864-016-2573-x) contains supplementary material, which is available to authorized users.

Current problems of barley breeding in Azerbaijan

The aim and tasks of the study. The aim of the study was to identify and select introduced from İCARDA barley accessions from a collection, which would have a complex of valuable economic features for practical use in breeding for salt tolerance, resistance to drought, diseases, as well as lodging resistance on irrigation in Azerbaijan.Material and methods. The dryland experiments on drought resistance were carried out at Gobustan and Jalilabad Zonal Experiment Stations, Shekin Experiment Farm of Azerbaijan Institute of Agriculture in 2006-2014; on salt tolerance - at Shirvan Experiment Station in Azerbaijan Scientific-Research Institute of Cotton; in optimal conditions of irrigation - at Absheron Production and Experiment Farm and Terter Zonal Experiment Station. The study included more than 2,000 barley accessions.To assess the degree of soil salinity, the VA Kovda and GZ Azizov’s scale was used. Variations in the yield structure elements and yield capacity in comparison with the standard served as an index of resistance to stress.The study, phenological observations and evaluation of variety resistance to diseases were performed according to the International Classifier CMEA. Diseases were assessed on the natural infectious background in the phase of leaf-tube formation-ear formation. Lodging resistance was evaluated in the phase of ear formation-ripening.Results and discussion. According to the duration of the vegetation period, the accessions were divided into early-ripening (5-9 days earlier than the standard), mid-ripening (simultaneously with the standard or 1-4 days later) and late-ripening (5 or more days later than the standard). Genetic sources of earliness (176-190 days) were identified.According to the plant height, accessions were divided into five groups: 41-60 cm- semi-dwarf (138 accessions); 61-70 cm– short-growing (691 accessions); 71-80 cm– medium short-growing (827 accessions); 81-90 cm- medium-growing (301 accessions); and 96-110 cm- medium tall-growing (43 accessions). Morphological analysis demonstrated that the majority of lodging accessions were tall-growing. All the short-growing and medium short-growing varieties generally had resistance of 7-9 points. There is a negative correlation (r = - 0.418) between plant height and lodging resistance.Differences in susceptibility to plant diseases were noticeable between varieties. Among the studied accessions, 43.1% were mildly or moderately affected (1-5 points) by powdery mildew and barley leaf stripe disease. Approximately the same number (42.9%) were resistant (7 points), and only 14% were highly resistant (9 points).Among the elements of the productivity structure, 100-grain weight, ear length, spikelet number per ear comparatively less varied under stress, and productive tillering, kernel number per ear and grain yield varied the most strongly. These figures parameters slightly changed in stress-tolerant accessions.Conclusions. Thus, we selected accessions having a complex economically valuable features, which are worth more attention as source material for breeding barley varieties in different regions of Azerbaijan.

Evaluation of winter barley breeding lines for productivity and adaptability under environments of forest- steppe of Ukraine

Purpose. To evaluate new winter barley breeding lines under environments of Forest-Steppe of Ukraine for productivity and resistance to abiotic and biotic factors, to select the best ones for complex of agronomic traits as candidates-varieties to be transferred to State Strain Testing.Material and methods. The study was conducted at Breeding Barley Laboratory of the V. M. Remeslo Myronivka Institute of Wheat of NAAS in 2009-2014. Winter barley breeding lines of competitive strain test of were the object of the research. Field evaluation for winter hardiness, duration of cropping season, resistance to lodging and to major leaf diseases was carried out. Adaptability indices were calculated by yield performance according to conventional methods.Results. In 2009-2010 field evaluation and rejection of breeding lines in control nursery and prove preliminary testing for winter hardiness has been carried out. Subsequently under relatively favorable wintering conditions the breeding lines were studied in the competitive strain testing for morpho-physiological traits related to winter barley winter hardiness such as sugar levels accumulated in tillering nodes at the moment of stopping growth and development of apical points in autumn and winter periods.With a number of methods to assess the adaptability mathematical and statistical analysis of yield for 40 winter barley breeding lines in 2012-2014 was carried out and parameters of plasticity and stability were defined. Based on the indices defined ranking and calculation of adaptability rating were carried out. In addition, weather conditions during years of research were favorable to objective evaluation of breeding lines for resistance to lodging and several leaf diseases - powdery mildew, barley leaf stripe, net blotch, spot blotch and barley leaf rust. Breeding lines that combine higher levels of yield and resistance and moderate resistance to individual or set of the factors mentioned above in field conditions were identified.Conclusions. Resulted from a comprehensive study in competitive strain testing of MIW breeding lines Pallidum 4816 (Luxor / Myronivs’ky 87), Pallidum 4857 (Osnova / Myronivs’ky 87), Pallidum 4659 (Erfa / Radical // Kromoz) possessing the most optimal ratio of yield potential, parameters of adaptability, resistance and moderate resistance to abiotic and biotic factors were singled out. These lines will be transferred to the State Strain Testing of Ukraine as new winter barley varieties.

Characterization of Pyrenophora graminea Markers Associated with a Locus Conferring Virulence on Barley

The fungus Pyrenophora graminea is the causal agent of barley leaf stripe disease. Two leaf stripe isolates PgSy3 (exhibiting high virulence on the barley cultivar 'Arabi Abiad') and PgSy1 (exhibiting low virulence on Arabi Abiad), were mated and 63 progeny were isolated and phenotyped for the reaction on Arabi Abiad. The population segregated in a 1:1 ratio, 32 virulent to 31 avirulent (<TEX>${\chi}^2$</TEX> = 0.05, P = 0.36), indicating single gene control of PgSy3 virulence on Arabi Abiad. Among 96 AFLP markers identified, three AFLP markers, E37M50-400, E35M59-100 and E38M47-800 were linked to the virulence locus VHv1 in isolate PgSy3. The results of this study indicate that (the three markers) are closely linked to VHv1 and are unique to isolates carrying the virulence locus. This work represents an initial step towards map-based cloning of VHv1 in P. graminea.