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Pots experiment has been conducted in the 2017 - 2018 season in plant protection directory/Abu-ghreeb/Baghdad. Ten wheat varieties were used in recent study (Bohooth10, Bohooth22, Bohooth95, Bohooth158, Ipaa99, Sham6, Abu-ghreeb, Adenh, Latefiya and Rasheed), to study their resistance and susceptibility to the one T.tritici isolate which causing common bunt disease on wheat crop. Seeds of wheat contaminated with teliospors of T. tritici isolate and sowing in pots at three replication for each variety, the incidence ratio, plant height and length of spike was estimated at the end of growth season. Lowest incidence ratio observed in Rasheed, Bohooth 95 and Bohooth 10 (0.0, 1.5, 1.8) % respectively without significant differences between them, highest incidence ratio was recorded in Bohooth 22 variety 33% with significant differences comparison with other varieties. Other tested variety recorded incidence ratio about (23-27) %. Result from this study show reduction in plants height and length of spikes in the all bunted plants with significant differences comparison with the control (healthy plants). from recent study can be concluded, wheat varieties differs in their resistance and susceptibility to common bunt disease, and this disease caused reduction in the plant height and length of spike in the bunted plants. [ABSTRACT FROM AUTHOR]

This is the first study of proteomics of wheat bunt fungi Tilletia controversa (TCK), T. caries (TCT), and T. foetida (TFL) using the iTRAQ technique. Based on the relative quantities of specific proteins between each two pathogens, we found 50 up-regulated and 80 down-regulated protein genes in TCK compared to TFL, 62 up-regulated and 82 down-regulated protein genes in TCT compared to TFL, 47 up-regulated and 30 down-regulated protein genes in TCK compared to TCT, and there were 1 protein of up-regulated and 4 proteins of down-regulated in the three pairs. These protein data could be of great value for exploring the key proteins which play an important role in the interactions of these pathogens with their host. Some of them could be valuable for differentiating the three pathogens with monoclonal antibodies produced by the specific proteins and may enable in-site detection of the pathogens and performing routine monitoring as a diagnostic assay in wheat shipments. [ABSTRACT FROM AUTHOR]

Specific scope: This Standard describes a diagnostic protocol for Tilletia indica. It should be used in conjunction with PM 7/76 Use of EPPO diagnostic protocols. Specific approval and amendment: This Standard was originally developed under the EU DIAGPRO Project (SMT 4‐CT98‐2252) by a partnership of contractor laboratories and interlaboratory comparison in European countries. First approved as an EPPO Standard in 2003–09. First revision approved in 2007–09. Second revision approved on 2017–11. Although this EPPO Diagnostic Standard differs in terms of format it is in general consistent with the content of the IPPC Standard adopted in 2014 on Tilletia indica (Annex 4 to ) with the following exceptions. (1) In the EPPO region, as the pest is not present, a higher confidence in the results is required, a sieve wash test should be carried out (optional in the IPPC protocol). (2) When fewer than 10 teliospores are found the options should allow testing the (<10) teliospores with conventional or real‐time PCR (this was not an option in the IPPC protocol flow chart, although it was stated that direct real‐time PCR could be used on individual teliospores in the text). (3) The method for extracting teliospores from untreated seed or grain by size‐selective sieving is slightly different based on the experience in the region (European Union test performance study). The EPPO Diagnostic Standard also includes a test for a direct real‐time PCR for use on pellets (developed in 2016). Some additional information on methods for morphological identification, from the former version of the EPPO Standard, which are not in the IPPC protocol are included in this protocol in Appendix 3 as they were considered useful by the members of the Panel on Diagnostics in Mycology. [ABSTRACT FROM AUTHOR]

Key message: The Bt9 resistance locus was mapped and shown to be distinct from the Bt10 locus. New markers linked to Bt9 have been identified and may be used to breed for resistance towards the seed-borne disease. Abstract: Increasing organic wheat production in Denmark, and in other wheat-producing areas, in conjunction with legal requirements for organic seed production, may potentially lead to a rise in common bunt occurrence. As systemic pesticides are not used in organic farming, organic wheat production systems may benefit from genetic resistances. However, little is known about the underlying genetic mechanisms and locations of the resistance factors for common bunt resistance in wheat. A double haploid (DH) population segregating for common bunt resistance was used to identify the chromosomal location of common bunt resistance gene Bt9. DH lines were phenotyped in three environments and genotyped with DArTseq and SSR markers. The total length of the resulting linkage map was 2882 cM distributed across all 21 wheat chromosomes. Bt9 was mapped to the distal end of chromosome 6DL. Since wheat common bunt resistance gene Bt10 is also located on chromosome 6D, the possibility of their co-location was investigated. A comparison of marker sequences linked to Bt9 and Bt10 on physical maps of chromosome 6D confirmed that Bt9 and Bt10 are two distinct resistance factors located at the distal (6DL) and proximal (6DS) end, respectively, of chromosome 6D. Five new SSR markers Xgpw4005-1, Xgpw7433, Xwmc773, Xgpw7303 and Xgpw362 and many SNP and PAV markers flanking the Bt9 resistance locus were identified and they may be used in the future for marker-assisted selection. [ABSTRACT FROM AUTHOR]

Resistance to common bunt and to dwarf bunt in winter wheat cultivars recently registered in the Czech Republic was studied in artificially inoculated field trials in the years 2013−2015. In trials with common bunt, seeds of each experimental series were inoculated with a different mixture of isolates. In dwarf bunt trials, the soil surface was inoculated with a natural bunt population from a single locality. Several selected unregistered wheat cultivars, triticale cultivars and cultivars/lines known as sources of dwarf bunt resistance were also included in the trials with dwarf bunt. Out of the recently registered winter wheat cultivars only cv. Genius showed resistance to common bunt in both test years. Cv. Sailor was highly resistant to common bunt only in one trial, but not in other trials with different inoculum. Cv. Saturnus and the registered cv. Potenzial showed the lowest incidence of dwarf bunt in both years. The triticale cultivars were highly resistant to dwarf bunt compared to the wheat cultivars used as checks. High resistance to dwarf bunt in the tested sources of resistance was confirmed. [ABSTRACT FROM AUTHOR]

Common bunt caused by Tilletia sp. is a very destructive and dangerous seed-borne fungal disease and may cause serious economic losses in worldwide. Wheat cultivars carrying resistance genes are used as an alternative fight method instead of chemical fungicides against common bunt disease. These resistance genes in wheat are called as bt genes. Until today, a few number of bt genes has been detected in wheat by using various molecular markers. However, development of more molecular markers for detection of all bt genes in wheat is required. In this study, detection of five bt genes called as bt-5, bt-8, bt-10, bt-11 and bt-12 was carried in ten registered local wheat varieties (Sertak 52, Bolal 2973, Demir, Kutluk, Harmankaya 99, Pehlivan, Tosun Bey, 4-11, Sönmez 01, Bezostaja-1) using PCR-based molecular markers, microsatellite and RAPD. PCR-amplified fragments were separated on 1.3% agarose gel. The obtained DNA bands were scored as present or absent for detection of bt genes. For comparison, the virulence rates of five Tilletia foetida (syn. leaves) isolates against ten wheat varieties were obtained from our field results. We observed that wheat varieties Kutluk and 4-11 carrying bt-10 and bt11 genes are more resistant to disease in field. [ABSTRACT FROM AUTHOR]

Common bunt caused by species of Tilletia genus presents an important and constantly increasing cause from an economically point of view and this because of major climate change in recent years that have contributed to record high production losses, sometimes even with a technology culture applied correctly. During 2011-2013 period, at the Ezareni Farm from the University of Agricultural Sciences and Veterinary Medicine there were tested 24 domestic and foreign wheat varieties grown under non-irrigated and artificially infected conditions with Tilletia caries (DC.) Tul . pathogen. The wheat caryopses artificially infected with fungus teliospores were sown in a randomized block type experiences in 4 repetitions. During the growing season there have been made constant observations in order to determine the morphological and biometric characteristics of wheat varieties under study. Considering the climatic conditions, based on observations that were made during of the two-year study, the 24 varieties showed a high variability resistance to Tilletia caries (DC.) Tul. pathogen attack. Following artificial infection of 24 wheat varieties there were identified 13 resistant varieties with values of the attack spikes smaller than 5%, 6 tolerant varieties with a disease frequency between 5-10% and two susceptible varieties with frequency of attacked ears upwards of 15%. [ABSTRACT FROM AUTHOR]

Winter wheat cultivars recently registered in the Czech Republic were tested in three-year field tests for resistance to common bunt. Seeds were inoculated with a mixture of local strains of Tilletia tritici and T. laevis. None of the cultivars displayed a higher level of resistance compared with the resistant checks. The mean percentage of bunted ears in the three test series including checks was 39%. Mean bunt infection in resistant and susceptible checks was 2% and 63%, respectively. In the European Tilletia cooperative test performed in Prague-Ruzynĕ, thirty-five winter wheat cultivars from six countries were tested during 2007-2013. The cultivars Bill, Nadro, Quebon, Samurai, Stava and Tommi exhibited infection levels below 10% in the respective years of the test. Additionally, 75 breeding lines from six countries were tested. Infection levels below 1% were recorded in 56% of the lines and 1-10% levels in 19% of the lines. A close relationship between the resistant cvs. Tommi and Globus was confirmed using SSR allelic markers. [ABSTRACT FROM AUTHOR]

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Common bunt, caused byTilletia tritici(Bjerk.) G. Wint. in Rabenh. andT. laevisKϋhn in Rabenh., is an economically important disease of wheat (Triticum aestivumL.) worldwide. The hexaploid wheat cultivar ‘McKenzie’ possesses effective resistance against known races of common bunt in western Canada. Understanding the nature of this resistance through DNA marker mapping will be useful for breeding. Disease reaction toT. triticirace T19 andT. laevisrace L16 from field tests was analysed with simple sequence repeat markers for 174 doubled haploid lines using interval mapping. MarkersXgwm573andXwmc17, located on wheat chromosome 7B, were strongly associated with the resistance. The quantitative trait locus was designatedQCbt.spa-7B.1. The markers were validated on two other populations in which ‘McKenzie’ was in the parentage. The markers will be useful in breeding as a tool for selecting for common bunt resistance from ‘McKenzie’ and will assist in identifying the resistance among potential new sources. [ABSTRACT FROM AUTHOR]

The location of new genes for resistance to common bunt in wheat is valuable for gene pyramiding in breeding. For this purpose, the genetics of the relatively high level of resistance in the European winter wheat variety Trintella was investigated using a doubled haploid mapping population of a cross between Trintella and the susceptible variety Piko. The population was scored for bunt infection in the field for 2 years following inoculation with a mixture of teliospores of Tilletia tritici and T. laevis. A genetic map consisting of 29 linkage groups was constructed using polymorphic simple sequence repeat markers. This map was used for QTL analysis, and in both years, results indicated that resistance to common bunt could mostly be attributed to a gene on chromosome 1B, near to the centromere and closest to marker Xgwm273 on the short arm. Additionally, in 2008, smaller QTL effects were ascribed to chromosomes 7A and 7B, and another smaller QTL effect to chromosome 5B in 2009 only. [ABSTRACT FROM AUTHOR]

Pathogenic races of Tilletia caries and T. foetida, which cause common bunt of wheat (Triticum aestivum), and Tilletia contraversa, which causes dwarf bunt of wheat, have been identified previously by their reaction to 10 differential wheat lines, each containing single bunt resistance genes Bt1 through Bt10. The reactions of races to the differential wheat lines follow the classic gene-for gene system for host—pathogen interactions. The pathogens are closely related and resistance to both diseases in wheat is controlled by the same genes. To better define pathogenic races, six additional wheat lines containing the genes Bt11 through Bt15 and a wheat line with a resistance factor designated as Btp were added to the set of 10 differentials and tested with all named U.S. races of common bunt and dwarf bunt. In addition, new isolates of dwarf bunt, and common bunt from hybrids and field collections, were tested with all 16 differentials for race identification. Six new races of T. caries, five new races of T. foetida, and two new races of T. contraversa were identified. Races of common bunt virulent to Bt8 or Bt12, and dwarf bunt races virulent to the combinations of Bt11 and Bt12, and Bt8, Bt9, Bt10, Bt11, and Bt12, were identified for the first time. Comparison of the reactions of the common bunt races with the Bt14 and Bt15 differentials grown in different environments after initial infection showed that these genes are temperature sensitive, indicating they should be excluded from the set of differential lines to avoid ambiguity in determining virulent or avirulent reactions. In the previous list of bunt races, there were races that had the same reaction to the set of 10 differentials but were designated as different races. These races were not differentiated further with the six additional differentials, indicating that the duplicate races should be dropped from the list of pathogenic races. The new races of common bunt and dwarf bunt identified have unique patterns of virulence that allow specific targeting and elucidation of bunt resistance genes in wheat and will aid the development of bunt-resistant wheat cultivars. [ABSTRACT FROM AUTHOR]

The article describes the AC Readymade and AC Tempest winter wheat cultivars. The cultivars were selected from the Redwin Montana cultivars and are characterized as well suited to the relatively mild winter climate of Southern Alberta, Canada. Both cultivars demonstrate relatively late maturity, moderate height, exceptional straw strength, high test weight, large kernels, high grain protein content and moderate resistance to common bunt.

The article focuses on the management of common bunt in organic wheat through host resistance and seed treatments. It states that a continuing breeding program for resistant cultivars is essential for sustainable control of common bunt. It says that cultivars should have weed competitiveness and improved nutrient-use efficiency. Moreover, seed treatments in accordance with organic agriculture principles include the use of heat treatments, volatile compounds from fungi, and natural substances.

Aims: Dwarf bunt of wheat, caused by Tilletia controversa Kühn, is a destructive disease on wheat as well as an important international quarantined disease in many countries. The objective of this investigation was to develop a diagnostic molecular marker generated from amplified fragment length polymorphism (AFLP) for rapid identification of T. controversa. Methods and Results: A total of 30 primer combinations were tested by AFLP to detect DNA polymorphisms between T. controversa and related species. The primer combination E08/M02 generated a polymorphic pattern displaying a 451-bp DNA fragment specific for T. controversa. The marker was converted into a sequence-characterized amplified region (SCAR), and specific primers (SC-0149/SC-02415), designed for use in PCR detection assays, amplified a unique DNA fragment in all isolates of T. controversa, but not in the related pathogens. The detection limit with the primer set SC-0149/SC-02415 was 10 ng of DNA which could be obtained from 11 μg of teliospores in a 25- μl PCR reaction. Conclusions: An approach to distinguish T. controversa from similar pathogenic fungi has been developed based on the use of a SCAR marker. Significance and Impact of the Study: Development of the simple, high throughput assay kit for the rapid diagnosis of dwarf bunt of wheat and detection of T. controversa is anticipated in further studies. [ABSTRACT FROM AUTHOR]

The species of Tilletia which cause common bunt of wheat (Tilletia caries and Tilletia foetida) can cause major yield losses in common wheat (Triticum aestivum L.) and durum wheat (Triticum turgidum L.). The aim of this study was to test resistance to Tilletia spp. of eight F2 populations of wheat consisting of progenies derived from resistant x susceptible crosses. Tests were carried out in the field by artificial inoculation of wheat seeds with a mixture of spores of T. caries and T. foetida. Analysis of variance for the percentage of infected plants showed that there were statistically significant differences between tested F2 progenies (between the progenies derived from crosses) regarding percentage of infection with Tilletia spp. (varying between 18.4 and 63%). The progenies of four crosses were tested comparatively using two different doses of inoculum, in order to find out the infection degree. Significant differences were observed between the bunt incidence after inoculation with the two doses. Characterization of the resistance in F2 progenies allowed us to perform a genetic analysis on the inheritance of resistance to Tilletia spp. in F2 population. The chisquare (χ²) analysis showed that inheritance of resistance to Tilletia spp. in progenies of F2 segregating populations fit a 3:1 (resistant:susceptible) ratio for the segregation of a single major resistance gene. The exception is represented by the segregation of resistance in F2 progenies of five crosses that do not fit the expected ratio of 3:1, which is possible because of the small number of plants that could be evaluated in tested population. [ABSTRACT FROM AUTHOR]

Abstract: A bunt fungus, exhibiting a spore germination pattern unique to known reticulate-spored species of Tilletia was found infecting plants in seed production fields of Festuca rubra ssp. rubra (red fescue) and F. rubra ssp. fallax (Chewing''s fescue) in Oregon, and in seed lots of Lolium perenne (perennial ryegrass) from Australia and Germany. Teliospores germinated to form 20–40 uninucleate, non-conjugating basidiospores, and colonies derived from single basidiospores produced teliospores in culture. In inoculation studies using single basidiospore colonies, perennial ryegrass and L. perenne ssp. multiflorum (Italian or annual ryegrass) were infected. A phylogenetic analysis, based on ITS region rDNA, eukaryotic translation elongation factor 1 alpha, and the second largest subunit of RNA polymerase II demonstrated that the fescue and ryegrass bunts are conspecific, and distinct from known species of Tilletia. [Copyright &y& Elsevier]

Alien translocations in wheat have been exhaustively investigated relative to various diseases, except for common bunt. During the period 2005-2006, an experiment was carried out at the Lithuanian Institute of Agriculture (LIA) in an artificially inoculated nursery. The test cultivars represented the latest Western European winter wheat genotypes. The total mean winter wheat infection in the common bunt nursery was 80.9% and the mean for the selected 36 cultivars 76.2%. The high infection level enabled us to screen the cultivars for the level of partial resistance. Of the selected 36 cultivars with or without various alien translocations, only 'Quebon' was found to be resistant. The least infected cultivars 'Tommi' and 'Bill', can be classified as medium susceptible -- 15.0% and 17.2%, respectively. The rest of the cultivars were very susceptible, the mean infection level ranging from 53.5% to 98.8%. Cultivars with Aegilops ventricosa translocation were the least infected of the selected genotypes. The mean infection of eight cultivars was 74.9%, and the mean for the rest of the cultivars was 81.2%. As a result, this translocation could additionally possess some barely effective genes of partial resistance. Complex translocation from Secale cereale did not possess effective partial resistance. The mean infection of cultivars with other translocations was not really different from that of the selected cultivars. Cultivars with translocation from A. tauschii were infected more than the mean 87.4%, whereas cultivars with translocation from Triticum dicoccum were infected less than the mean 75.4%. [ABSTRACT FROM AUTHOR]

The genetics of Karnal bunt (KB) resistance were studied in populations derived from crosses of four resistant stocks (HD 29, W 485, ALDAN ‘S’/IAS 58, H 567.71/ 3*PAR) and a highly susceptible cultivar, WH 542. The plant materials screened for KB response consisted of F2, BC1 and RILs from all ‘Resistant’בSusceptible’ crosses and RILs from the six possible ‘Resistant’ × ‘Resistant’ crosses as well as the parents and F1s. The screening was performed under optimal conditions for disease development with a mixture of isolates from North Western Plains of India using the widely followed syringe method of inoculation. The KB scores of the F1 from the four ‘Resistant’ × ‘Susceptible’ crosses indicated partial dominance of resistance. Genetic analysis revealed that HD 29, W485 and ALDAN ‘S’/IAS 58 each carried two resistance genes whereas 3 genes were indicated in H 567.71/3*PAR. The six ‘Resistant × Resistant’ RIL sets showed that the genes in the four resistant stocks were different and that there may be as many as nine genes governing KB resistance in the four parents. [ABSTRACT FROM AUTHOR]

The effect of salicylic acid (SA) on peroxidase activity in wheat (Triticum aestivum L.) calli cocultured with the bunt pathogen Tilletia caries was studied. Fungal infection was shown to activate cytoplasmic peroxidase. SA suppressed total peroxidase activity but did not inhibit the peroxidase with pI ∼9.8. A novel chitin-specific peroxidase with pI ∼3.5 appeared after the SA treatment. The infection of S A-treated cells with Tilletia caries activated the isoenzymes with pI ∼3.5, ∼4.8, and ∼7.5 and stimulated their secretion into the culture medium. The ability of SA to control wheat peroxidase activity during pathogenesis is discussed. The important role of this control in plant defense responses to the bunt pathogen is emphasized. [ABSTRACT FROM AUTHOR]

Comparative genealogical analysis of North American (the United States and Canada) and Eastern European (Russia and Ukraine) winter wheat cultivars resistant and susceptible to common bunt has been performed. Analysis of variance applied to North American wheats has demonstrated that resistant and susceptible cultivars significantly differ from each other with respect to the contributions of common ancestors. The contributions of Oro (Bt4 and Bt7), Rio (Bt6), White Odessa (Bt1), and Florence (Bt3) to the resistant cultivars are significantly higher than their contributions to the susceptible ones. This demonstrates that the use of these resistance donors in wheat breeding for several decades has been effective. The contribution of PI-178383 (Bt8, Bt9, and Bt10) is considerably higher in the group of resistant cultivars bred after 1965. The mean contributions of Federation (Bt7) and Nebred (Bt4) are significantly higher in the group of resistant cultivars obtained before 1965; however, the differences in the contributions of these donors between new resistant and susceptible cultivars became nonsignificant. Among the Russian and Ukrainian cultivars, there are differences between groups of resistant and susceptible cultivars from different regions determined by the differences between the regional populations of the pathogen in racial composition. In the northern region, the contributions of the wheat grass (Agropyron glaucum) and the rye cultivar Eliseevskaya are significantly higher in the resistant cultivars; in the southern region, a local cultivar of the Odessa oblast is the prevalent resistant cultivar. In addition, cultivar Yaroslav Emmer is likely to be effective in the northern region; and foreign sources (Oro, Florence, Federation, and Triticum timopheevii), in the southern region. Very few sources of vertical resistance to common bunt are used for winter wheat breeding in Russia and Ukraine. The decrease in genetic diversity in favor of a few identical genes may cause adequate changes in the pathogen population and subsequent proliferation of the pathogen on the genetically identical substrate. A new interpretation of the resistance of line Lutescens 6028 as a source of new genes, Bt12 and Bt13, is suggested. Both genealogical and segregation analyses have shown that the genes determining the resistance of this line may be identical to those described earlier (Bt1, Bt3, Bt4, Bt6, and Bt7); and the high resistance of this line is determined by a combination of these genes. [ABSTRACT FROM AUTHOR]

Diagnosis of the teliospores of Tilletia indica (Karnal bunt) detected in wash tests is complicated by the fact that wheat grain can be contaminated by ‘look-alike’ species, namely Tilletia walkeri (ryegrass bunt) and Tilletia horrida (rice smut). Although morphological diagnosis is possible when there are relatively large numbers of teliospores present, it is difficult with only a few spores as there are significant overlaps in the characteristics of each species. Molecular methods can confirm presumptive identifications, but these take 2–3 weeks. Image analysis offers the potential for more rapid confirmation. An image analysis system was developed for use on bleached spores. Bleaching spores reveals additional morphological characters (spore profile and spore wall layers) that may be used in an image analysis system to discriminate species. The image-processing software automatically locates spores on a given image and calculates perimeter, surface area, number of spines and spine size, maximum and minimum ray radius, aspect ratio and roundness. Principal components analysis (PCA) is performed on the parameters to obtain a linear separation of spore species. Accuracy of 97% in separating T. indica and T. walkeri has been achieved in preliminary tests using PCA, but further evaluation is required. [ABSTRACT FROM AUTHOR]

Common bunt (Tilletia tritici syn. T. caries) is a significant seed-borne plant disease in organic agriculture. General measures in ecological crop protection like crop rotation and manuring have in practice failed to control this disease, and direct seed treatment may be necessary to ensure yield and food quality. The present study indicates that biological control can be successfully used without negative effects on seed germination and vigor. A combination of biocontrol agents and milk powder improves the efficacy of biocontrol. Application of compost to the soil increases the frequency of this disease. The potential role of biocontrol within the principles of ecological disease management is discussed. [ABSTRACT FROM PUBLISHER]

Focuses on Karnal bunt (Kb), a fungal disease of wheat, rye and triticale. Presence of Kb in a durum wheat seed lot during a routine seed germination inspection in Arizona; Decision of the United States Department of Agriculture's Animal and Plant Health Inspection Service to quarantine all Arizona; Cycle of the disease; Discussion on quarantine; Kb quarantine/eradication solution.

Examines the inheritance of common bunt resistance in androgenetically derived doubled haploid and random inbred populations of wheat, Triticum aestivum. Identification of various types of wheat; Reference to studies conducted on the understanding of inheritance of resistance to disease; Importance of this procedure in breeding programs.

Screening of durum wheat germplasm for resistance to common bunt (Tilletia foetida and T. caries) resulted in the identification of 26 resistant genotypes. The screening was made using nine common bunt isolates from the West Asia and North Africa (WANA) region. In one isolate the two pathogens were represented in ratio of l:l, whereas eight isolates contained only T. foetida. The correlation, principal components and clustering analyses grouped the genotypes into three clusters. Cluster one comprised genotypes with genetic interrelationship with Jennah Khetifa, a Maghrebian landrace. Cluster two comprised genotypes close to Senatore (S.) Cappelli and Hanrani, the latter is a landrace from Syria. Cluster three comprised advanced genotypes containing resistance genes from Mindum, a Turkish landrace. Results indicated that donor sources of resistance appear to be related to the three major sources mentioned. Cultivar S. Cappelli is considered resistant since it has been grown by farmers on a large scale for many years and remained resistant to common bunt throughout 7 years of testing. This resistance is assumed to be of a durable type. The isolates were also grouped into three clusters representing different ecological areas and the wheat types from which the isolates originated. We infer that the different clusters reflect the presence of three pathotype groups of the pathogens. [ABSTRACT FROM AUTHOR]

Twelve synthesized amphiploids involving Karnal bunt (Neovossia indica)-resistant accessions of Triticum monococcum, T. boeoticum and Aegilops squarrosa and susceptible but otherwise well adapted and high yielding T. durum cultivars were evaluated for Karnal bunt resistance under artificial inoculation conditions. All the synthetic amphiploids, except DWL 5031 x T. monococcum amphiploid, were free from Karnal bunt disease indicating that the Karnal bunt resistance of T. monococcum, T. boeoticum and Ae. Squarrasa is expressed in the presence of the durum complement. The importance and utilization of the amphiploids for breeding wheat varieties resistant to karnal bunt are discussed. [ABSTRACT FROM AUTHOR]

The effectiveness of various fungicide formulations containing carboxin and thiabendazole in eradicating teliospores of Tilletia controversa (dwarf bunt) from winter wheat seed was evaluated in the laboratory and the field. In the laboratory tests, the viability of teliospores washed from treated infested seed was greatly reduced as compared to the viability of teliospores washed from untreated infested seed, suggesting that carboxin and thiabendazole were primarily fungicidal. Field tests in two different years were established to determine if teliospores from treated infested seed could infect nearby untreated noninfested seed. Formulations containing carboxin were highly effective in reducing infection of healthy seed. No dwarf bunt infected plants developed in either year from seed treated with 'Vitaflo 250'. Furthermore, seedborne common bunt caused by Tilletia foetida was nearly eradicated by carboxin-containing formulations in one field test. Carboxin treatment of winter wheat seed infested with dwarf bunt teliospores will greatly reduce the danger of introducing this pathogen into new areas. [ABSTRACT FROM AUTHOR]

The article presents abstracts on plant pest and disease researches, which include TRI13 gene sequence difference among 3-acetyldeoxynivalenol producing Fusarium graminearum, bacterial communities assessment with high throughput 454-pyrosequencing use and wheat bunt historical significance.

Volatile organic compounds produced by the fungus Muscodor albus inhibit or kill numerous fungi. The effect of these volatiles was tested on dormant and physiologically active teliospores of the smut fungi Tilletia horrida, Tilletia indica, and Tilletia tritici, which cause kernel smut of rice, Karnal bunt of wheat, and common bunt of wheat, respectively. Reactivated rye grain culture of M. albus was used to fumigate dormant teliospores in dry Petri dishes and physiologically active teliospores on water agar for up to 5 days at 22 °C. Teliospores of all 3 species were incapable of germination when fumigated on agar for 5 days. When T. tritici on agar was fumigated only during the initial 48 h of incubation, viability was reduced by 73%-99%. Fumigation of dry loose teliospores of T. tritici caused a 69%-97% loss in viability, whereas teliospores within intact sori were not affected. Dormant teliospores of T. horrida and T. indica were not affected by M. albus volatiles. It appears that M. albus has potential as a seed or soil treatment for controlling seedling-infecting smuts where infection is initiated by germinating teliospores prior to seedling emergence. The volatiles were not effective for postharvest control of teliospores under conditions used in these experiments. [ABSTRACT FROM AUTHOR]

To develop winter wheat varieties suitable for organic farming, it is necessary to collect plant genetic resources resistant to common bunt, because no seed treatment (with synthetic pesticides) is allowed. For this purpose, the breeding lines developed at the Lithuanian Institute of Agriculture and winter wheat varieties registered in Lithuania were investigated during 2001-2004, using artificial inoculation with Tilletia tritici and Tilletia leavis spores. It was found that among advanced breeding lines 0.0-1.7% were very resistant and 0.0-16.2% resistant to common bunt. Among the gene collection varieties tested, 0.0-7.7% were very resistant and 1.6-36.2% resistant to common bunt depending on the year of testing. Most lines and varieties were infected by 10% to 50%. This means that development and collection of plant genetic recourses resistant to common bunt is one of the limiting factors in organic wheat breeding. Investigations of common bunt resistance of Lithuania-registered winter wheat varieties showed that among 26 varieties two -- 'Begra', 'Baltimor' -- were resistant while 'Korweta' and 'Bill' medium-resistant to common bunt. These varieties can be used in crosses to improve resistance to common bunt. The infection in most varieties reached 16.5-55.3%. The most susceptible varieties were 'Flair', 'Aspirant' and 'Pegasos' (infection 75.9-87.4%). The Lithuanian winter wheat variety 'Milda' was medium-susceptible and 'Ada', 'Seda', 'Alma', 'Širvinta' susceptible to Tilletia tritici. [ABSTRACT FROM AUTHOR]

Abstract Common bunt caused by Tilletia tritici and T. laevis has occurred worldwide and reduces yield and quality in common and durum wheats. The development of DNA markers linked to bunt resistance to race T1 in the cross, ‘Laura’ (S) × ‘RL5407’ (R), was carried out in this study based on the single head derived F4:5 and single seed derived F4:6 populations. Bulked segregant analysis was used to identify two random amplified polymorphic DNA (RAPD) markers linked to the gene for resistance to race T1 in the spelt wheat ‘RL5407’. The two markers identified, UBC548590 and UBC274988 , flanked the resistance gene with a map distance of 9.1 and 18.2 cM, respectively. The former was linked in repulsion phase to bunt resistance while the later was in coupling phase. The two RAPD markers and the common bunt-resistance gene all segregated in Mendelian fashion. Use of these two RAPD markers together could assist in incorporating the bunt-resistance gene from spelt wheat into common wheat cultivars by means of marker-assisted selection. [ABSTRACT FROM AUTHOR]

The reaction of tritordeum and its Hordeum chilense and Triticum spp. parents to common bunt incited by Tilletia tritici were determined in field experiments. H. chilense accessions were very resistant, and durum wheats exhibited high to moderate levels of resistance. Conversely, bread wheats were highly susceptible. Resistance from H. chilense was expressed in the amphiploids, although the level of resistance was partially diluted at higher ploidy levels. Hexaploid tritordeums were immune to the disease; some infection was observed among the octoploids but at much lower levels than in their respective wheat parents. [ABSTRACT FROM AUTHOR]

Fourteen Mexican genotypes of bread wheat (Triticum aestivum L.) with good to moderate levels of resistance to Karnal bunt (Tilletia indica (Mitra)) were crossed with the highly susceptible cultivar WL711 to determine the genetic basis of resistance. The parents, F1, F2 and backcross populations of the 14 crosses were evaluated under artificial epiphytotic conditions during the 1993-94 season for Karnal bunt resistance. The F1 data suggested that the resistance was dominant to partially dominant over susceptibility. The χ² analysis of the segregation ratios in the F2 and backcross generations indicated that the resistance in the wheat genotypes Luan, Attila, Vee # 7/Bow, Star, Weaver, Milan, Sasia and Turacio/Chil is controlled by two genes. The resistance in genotypes Cettia, Irena, Turaco, Opata, Picus, and Yaco was found to be conditioned by a single dominant gene. The genotypes with two genes for resistance expressed a higher level of resistance than those with a single gene and, therefore, are better sources of resistance to Karnal bunt. [ABSTRACT FROM AUTHOR]

In 1985 severe bunt was encountered in a crop of wheat grown from organomercury-treated seed. Circumstantial evidence suggested that the soil had been contaminated by airborne spores of the fungus from a nearby crop which was being harvested at the same time as the affected crop was being sown. [ABSTRACT FROM AUTHOR]

Genetic resistance to common bunt is a cost-effective, environmentally friendly, and sustainable approach to controlling the disease. To date, 16 race specific common bunt resistance genes (Bt1-Bt15 and Btp) have been reported in wheat. However, a limited number have been mapped and few markers have been identified, which limits the usage of molecular markers in a marker-assisted breeding program. A total of 125 synthetic hexaploid wheats (SHWs) were evaluated for reactions to a mixture of common bunt races under field conditions in Turkey in 2016 and 2017. The objectives of this study were to identify common bunt resistant genotypes, identify genomic regions conferring resistance to common bunt using 35,798 genotyping-by-sequencing derived single nucleotide polymorphisms (SNPs), and investigate the significant SNPs present within genes using the functional annotations of the underlying genes. We found 29 resistant SHWs that can be used in wheat breeding. The genome-wide association study identified 15 SNPs associated with common bunt resistance and a haplotype block comprising three SNPs in perfect linkage disequilibrium. Five of them were novel and were located on chromosomes 2A, 3D, and 4A. Furthermore, seven of the 15 SNPs were found within genes and had annotations suggesting potential role in disease resistance. This study identified several favorable alleles that decreased common bunt incidence up to 26% in SHWs. These resistant SHWs and candidate genomic regions controlling common bunt resistance will be useful for wheat genetic improvement and could assist in further understanding of the genetic architecture of common bunt resistance. [ABSTRACT FROM AUTHOR]

A Karnal bunt (KB)-free wheat stock (‘KBRL22’) obtained from a cross of two resistant lines (‘HD29’ and ‘W485’) was used as a donor to introgress the KB-free trait into ‘PBW343’ (an ‘Attila’ sib), the most widely grown wheat cultivar in India. The number of KB-free and KB-affected plants in BC1, BC2, BC3 and BC4 as well the F2 was recorded after artificial inoculations. The segregation pattern in these generations clearly indicated two independently segregating, dominant genes which jointly confer the KB-free attribute. The importance of the KB-free line generated in this experiment is discussed. [ABSTRACT FROM AUTHOR]

The article presents a reprint of the article "The Organism Causing Dwarf Bunt of Wheat," by I.I. Conners, which appeared in the periodical "Canadian Journal of Botany." According to a study it was revealed that the organism was different from the common bunt fungus tilletia caries. It mentions that it was likely due to some grass smut, which affected native species of agropyron in Europe and Turkestan.

Discusses an abstract of the study "Markers to and chromosome location of the resistance gene Bt12 to common bunt in common wheat (Triticum aestivum)," by S. Wang and colleagues, presented at the Canadian Phytopathological Society's 2004 Annual Meeting in Ottawa, Ontario.

Reactions to eight isolates of Karnal bunt, Neovossia indica, collected from seven different locations in northern India were studied on 13 host lines, including cultivars and breeding lines of Triticum aestivum, Triticum durum and Triticosecale in all possible combinations. The incidence of Karnal bunt varied from zero in PBW 34 and PBW 248 with isolates Ni8 and Ni2, respectively, to as high as 66.8% in a highly susceptible cultivar WL 711 with isolate Ni5. The differences in disease incidence among cultivars and isolates were highly significant. All the isolates could be distinguished on the basis of differential reactions on one or more of the host lines. Even the most resistant lines of durum (PDW 215), triticale (TL 1210) and wheat (HD 29) could be distinguished by the differential disease reaction with one or more of the eight isolates. The cultivar–isolate interaction for disease score was highly significant, indicating the probable existence of a gene-for-gene relationship in this host–pathogen system. [ABSTRACT FROM AUTHOR]