Assessing disease severity – no problem?

Die Bewertung der Resistenz von Getreidesorten erfordert eine möglichst genaue Schätzung des Befalls mit unterschiedlichen Blatt- und Ährenkrankheiten. Mit Hilfe der vorliegenden Webanwendung kann das Schätzen des prozentualen Befalls auf der Grundlage von konstruierten Befallsbildern trainiert werden. Dies erhöht die Genauigkeit, Vergleichbarkeit und Reproduzierbarkeit von Befallsschätzungen schon nach kurzer Übungszeit. Die Webanwendung ist im Internetangebot des Julius Kühn-Institutes – Bundesforschungsinstitut für Kulturpflanzen verfügbar.Disease assessment of the resistance of cereal cultivars to various leaf and ear diseases requires estimations of disease severity that are as accurate as possible. Assessment of the percentage of diseased area can be practised with the given web application based on constructed drawings of cereal diseases. Thus, accuracy, comparability and reproducibility of disease assessments can be increased after a short time of practising. The web application is available on the webpage of the Julius Kühn-Institute – Federal Research Centre for Cultivated Plants

Analyse der Virulenzsituation des Roggenschwarzrostes (Puccinia graminis f. sp. secalis) im ökologischen Landbau zur Züchtung resistenten Roggens

Organic Agriculture is especially affected by the increasing spread of stem rust in rye (Puccinia graminis f. sp. secalis) because there is a lack of resistant cultivars in Germany. To analyze the virulence situation of rye stem rust, 71 single-pustule-isolates were established and 30 of those were tested with a differential set consisting of 19 lines. The isolates could be classified into 22 different pathotypes. Only seven pathotypes could be found more than once. Most of the isolates showed a complexity of five virulences. In a preliminary analysis a Simpson index of 0,98 was found indicating a high level of diversity of German stem rust populations. Nine of 19 tested lines reacted fully resistant in seedling stage. In 2011, 70 and 30 rye populations, were cultivated under organic conditions at three and five field sites, respectively, to determine the level of adult-plant resistance. The most common cultivars Recrut, Conduct, Amilo, Firmament®, Lichtkornroggen®, Rolipa, and Lautenbacher were highly susceptible to stem rust under artificial infection with disease severities of about 50%. Twelve rye populations contained resistant plants in varying frequencies resulting in disease severities ranging from 6-34%

Kontrolle des Roggenschwarzrostes, Puccinia graminis f. sp. secalis, im Ökologischen Landbau durch Züchtung resistenten Roggens

Der Ökologische Landbau (ÖLB) ist von der zunehmenden Ausbreitung des Roggenschwarz-rostes, Puccinia graminis f. sp. secalis, besonders betroffen, da resistente Roggensorten bisher nicht zur Verfügung stehen. Zur Analyse der Virulenzsituation des Roggenschwarzrostes wurden 389 Einpustelisolate (EPI) hergestellt, von denen 323 mit einem Differentialsortiment aus 15 Inzuchtlinien getestet wurden. Die EPI konnten 226 Pathotypen zugeordnet werden, von denen nur 56 Pathotypen häufiger als einmal vorkamen. Die Mehrzahl der Isolate wies in den Jahren 2011, 2012 und 2013 eine Komplexität von sieben, sechs bzw. fünf auf. Keine der 15 Differentiallinien reagierte vollständig resistent. Mit einem Simpson-Wert von 0,99 zeigt sich eine maximale Diversität der deutschen Schwarzrostpopulation. Das im Rahmen des Projektes entwickelt Isolatesortiment deckt das aktuelle Virulenzspektrum der Schwarzrostpopulationen ab und kann auch zukünftig genutzt werden, um die Wirksamkeit von Schwarzrostresistenzen zu prüfen. Außerdem kann das Auftreten neuer Virulenzen in der Schwarzrostpopulation jetzt rechtzeitig erkannt und wirtschaftlicher Schaden abgewendet werden. Zur Ermittlung der Adultpflanzen-Resistenz wurden bis zu 70 Genetische Ressourcen sowie adaptiertes, selbstfertiles Roggenmaterial unter ökologischen Bedingungen an fünf Feldstandorten je Jahr angebaut. Das Inokulum für die künstlichen Inokulationen wurde am JKI produziert und die Inokulation fand im Entwicklungsstadium BBCH37 (Mai 2013 und Mai 2014) statt. Die im Ökologischen Landbau verwendeten Sorten Recrut, Conduct, Amilo, Firmament®, Lichtkornroggen®, Rolipa und Lautenbacher waren nach künstlicher Infektion hoch anfällig gegenüber Schwarzrost mit Befallsstärken von über 50%. Nach drei Versuchs-jahren konnten insgesamt 17 Populationssorten aus Österreich (Tiroler, Kärntner, Oberkärnt-ner), Russland (Hy75/81, Hy2407/87, Talwoskaja 29, Hy9a/86, Talowskija, Zidlochowicke rane, Instituckie Wcz), den USA (Wheeler, Elbon, Wrens Abruzzi, Gator, Alfa), und Argentinien (Manfredi), mit mittleren Befallswerten von ≤30 % für die Züchtung bereitgestellt werden. Das Projekt leistete damit einen erheblichen Beitrag zur Nutzung der Biodiversität des Roggens und zur Optimierung der Resistenzzüchtung im ÖLB. Resistente Roggensorten werden in Zukunft eine effiziente Kontrolle des Roggenschwarzrostes ermöglichen, die den Grundsätzen des ÖLB entspricht. Das Projekt kann den Hauptaufgaben 2.1, 2.3, 2.4 und 2.14 des Forschungsplanes des BMELV zugeordnet werden und ist Grundlage für die Weiterentwicklung von Strategien zur Nutzung von Schwarzrostresistenzen sowie die Bewertung der Widerstandfähigkeit von Roggen gegenüber Schwarzrost

Diagnosing potato wart disease – reliable identification and assessment of resting spores of Synchytrium endobioticum

Die Dauersporangien des Kartoffelkrebserregers, Synchytrium endobioticum, stellen aufgrund ihrer Widerstandsfähigkeit gegenüber chemischer Behandlungen eine besondere Gefährdung in Form von Langzeitkontamination von Resterden und Ackerflächen dar. Sie weisen ein breites Spektrum an Erscheinungsformen mit spezifischen Charakteristika auf und sind deshalb eine besondere Herausforderung bei der sicheren Diagnose von Kartoffelkrebs. Neben der Bewertung als Synchytrium endobioticum stellt die Beurteilung der Vitalität des einzelnen Sporangiums auf Basis mikroskopischer Untersuchungen eine Herausforderung dar. Die Referenzbildsammlung soll eine Entscheidungshilfe und Schulungsmaterial für die Diagnoselabore bieten. Exemplarisch werden Sporangien­bilder verschiedener Kategorien bewertet und Besonderheiten hervorgehoben. Die Referenzbildsammlung ist auf der Homepage des Nationalen Referenzlaboratoriums des Julius Kühn-Instituts für registrierte Nutzer abrufbar.Due to their resistance to chemical treatments, the resting spores of Synchytrium endobioticum the causal agent of potato wart disease pose a particular threat in the form of long-term contamination of residual soil and arable land. They show a wide spectrum of characteristic morphological phenotypes and are therefore a particular challenge in the reliable diagnosis of potato wart. In addition to addressing them as Synchytrium endobioticum, assessing the viability of the resting spore based on microscopic examination is challenging. The reference image collection is intended to provide decision support and training material for diagnostic laboratories. Exemplary images of resting spores/sporangium of different categories are evaluated and special characteristics are highlighted. The reference image collection is available on the homepage of the National Reference Laboratory of the Julius Kühn Institute for registered users

Analysis of powdery mildew resistance in the Spanish barley core collection

24 Pag., 4 Tabl., 2 Fig. The definitive version is available at: www3.interscience.wiley.comThe Spanish Barley Core Collection, consisting of one hundred and fifty-nine landrace-derived inbred lines and sixteen cultivars, was characterized for resistance to powdery mildew (Blumeria graminis f. sp. hordei) using a set of 27 isolates with a wide spectra of virulences/avirulences on most of the genes expected to occur in Europe. No landrace-derived line and no cultivar were resistant to all the isolates but at least three landraces showed infection types below 2 for 23 isolates. Twenty-two landraces and one cultivar showed resistance against half of the isolates used. Eleven isolates were sufficient to separate the majority of resistance profiles. In total, thirty-four resistance spectra were detected and fourteen resistance genes/alleles were postulated alone or in combination: MlLa, Mlh, Mlg, Mla22, Mla7(Mlu), Mla7(Mlk), Mlk, Mla12, Mla9, Mla3, Mla6(Mla14), Mlra and Mla1. The majority of resistance spectra are composed only by one line. Resistance in twenty-one landrace-derived lines and four cultivars was based on either unidentified genes or combinations of known and unknown genes/alleles. Therefore, the SBCC may be a source for broadening the genetic base of powdery mildew resistance.This research was funded by projects AGL2004-05311 and AGL2007-63625, granted by the Spanish Ministry of Science and Innovation. C.S. holds an I3P-Doc contract from CSIC. C.S. was supported by mobility fellowships from DFG, CSIC and Fundación Caja Inmaculada.Peer reviewe

Transformations of the National:Rammstein’s “Deutschland” as a Provocation of German History

This contribution examines the nexus between ‘the political’ and popular music from an interdisciplinary perspective. Using Rammstein’s highly provocative single “Deutschland” (2019) as an example, this case study showcases multiple different and often contradictory readings of the band’s work with a view to its textual, visual, sonic and performative dimensions. Overall, this contribution suggests that the political in Rammstein oscillates between self-reference and historical reference, between deconstruction and marketability, and between scandalous irony and ambiguous sincerity

Wheat Stem Rust Back in Europe: Diversity, Prevalence and Impact on Host Resistance

The objective of this study was to investigate the re-emergence of a previously important crop pathogen in Europe, Puccinia graminis f.sp. tritici, causing wheat stem rust. The pathogen has been insignificant in Europe for more than 60 years, but since 2016 it has caused epidemics on both durum wheat and bread wheat in local areas in southern Europe, and additional outbreaks in Central- and West Europe. The prevalence of three distinct genotypes/races in many areas, Clade III-B (TTRTF), Clade IV-B (TKTTF) and Clade IV-F (TKKTF), suggested clonal reproduction and evolution by mutation within these. None of these genetic groups and races, which likely originated from exotic incursions, were detected in Europe prior to 2016. A fourth genetic group, Clade VIII, detected in Germany (2013), was observed in several years in Central- and East Europe. Tests of representative European wheat varieties with prevalent races revealed high level of susceptibility. In contrast, high diversity with respect to virulence and Simple Sequence Repeat (SSR) markers were detected in local populations on cereals and grasses in proximity to Berberis species in Spain and Sweden, indicating that the alternate host may return as functional component of the epidemiology of wheat stem rust in Europe. A geographically distant population from Omsk and Novosibirsk in western Siberia (Russia) also revealed high genetic diversity, but clearly different from current European populations. The presence of Sr31-virulence in multiple and highly diverse races in local populations in Spain and Siberia stress that virulence may emerge independently when large geographical areas and time spans are considered and that Sr31-virulence is not unique to Ug99. All isolates of the Spanish populations, collected from wheat, rye and grass species, were succesfully recovered on wheat, which underline the plasticity of host barriers within P. graminis. The study demonstrated successful alignment of two genotyping approaches and race phenotyping methodologies employed by different laboratories, which also allowed us to line up with previous European and international studies of wheat stem rust. Our results suggest new initiatives within disease surveillance, epidemiological research and resistance breeding to meet current and future challenges by wheat stem rust in Europe and beyond.info:eu-repo/semantics/publishedVersio

Diagnosis of quarantine organisms at the JKI in the National Reference Laboratory for organisms harmful to plants

Dem JKI wurde im April 2019 durch das Bundesministerium für Ernährung und Landwirtschaft (BMEL) die Funktion des nationalen Referenzlaboratoriums (NRL) für Schadorganismen der Pflanzen zugewiesen. Mit dieser Funktion des NRL für Deutschland sind bestimmte Zuständigkeiten und Aufgaben verbunden, die in der EU-Verordnung 2017/625 (EU, 2017) geregelt sind. Dazu gehören auch Referenzuntersuchungen bzw. die Diag­nose von Quarantäneschadorganismen (QSO). Das NRL stellt eine übergeordnete Einheit innerhalb des JKI dar. Durch insgesamt 14 Prüflabore der JKI-Institute für Pflanzenschutz in Ackerbau und Grünland (A), nationale und internationale Angelegenheiten der Pflanzengesundheit (AG), Epidemiologie und Pathogendiagnostik (EP), Pflanzenschutz in Gartenbau und Forst (GF), Pflanzenschutz in Obst- und Weinbau (OW) wird die Referenzfunktion bei der Diagnose zu verschiedensten (Quarantäne)-Schadorganismen der Pathogengruppen Bakterien, Insekten, Nematoden, Pilze (einschließlich Oomyceten), Phytoplasmen und Viren wahrgenommen.In April 2019, the JKI was officially designated as the Natio­nal Reference Laboratory (NRL) for organisms harmful to plants by the Federal Ministry of Food and Agri­culture (BMEL). This function as NRL for Germany is associated with certain responsibilities and tasks, which are specified in the EU Regulation 2017/625 (EU, 2017). This also includes reference tests and the diagnosis of quarantine pests, respectively. The NRL represents a super­ordinate unit inside JKI. A total of 14 test laboratories from different JKI institutes, namely for Plant Protection in Field Crops and Grassland (A), for National and International Plant Health (AG), for Epidemiology and Pathogen Diagnostics (EP), Plant Protection in Horti­culture and Forests (GF), and for Plant Protection in Fruit Crops and Viticulture (OW) are in charge to carry out a reference function in the diagnosis of (quarantine) pests in the pathogen groups of bacteria, fungi (including oomycetes), insects, nematodes, phytoplasma und viruses

Multiple alleles for resistance and susceptibility modulate the defense response in the interaction of tetraploid potato (Solanum tuberosum) with Synchytrium endobioticum pathotypes 1, 2, 6 and 18

The obligate biotrophic, soil-borne fungus Synchytrium endobioticum causes wart disease of potato (Solanum tuberosum), which is a serious problem for crop production in countries with moderate climates. S. endobioticum induces hypertrophic cell divisions in plant host tissues leading to the formation of tumor-like structures. Potato wart is a quarantine disease and chemical control is not possible. From 38 S. endobioticum pathotypes occurring in Europe, pathotypes 1, 2, 6 and 18 are the most relevant. Genetic resistance to wart is available but only few current potato varieties are resistant to all four pathotypes. The phenotypic evaluation of wart resistance is laborious, time-consuming and sometimes ambiguous, which makes breeding for resistance difficult. Molecular markers diagnostic for genes for resistance to S. endobioticum pathotypes 1, 2, 6 and 18 would greatly facilitate the selection of new, resistant cultivars. Two tetraploid half-sib families (266 individuals) segregating for resistance to S. endobioticum pathotypes 1, 2, 6 and 18 were produced by crossing a resistant genotype with two different susceptible ones. The families were scored for five different wart resistance phenotypes. The distribution of mean resistance scores was quantitative in both families. Resistance to pathotypes 2, 6 and 18 was correlated and independent from resistance to pathotype 1. DNA pools were constructed from the most resistant and most susceptible individuals and screened with genome wide simple sequence repeat (SSR), inverted simple sequence region (ISSR) and randomly amplified polymorphic DNA (RAPD) markers. Bulked segregant analysis identified three SSR markers that were linked to wart resistance loci (Sen). Sen1-XI on chromosome XI conferred partial resistance to pathotype 1, Sen18-IX on chromosome IX to pathotype 18 and Sen2/6/18-I on chromosome I to pathotypes 2,6 and 18. Additional genotyping with 191 single nucleotide polymorphism (SNP) markers confirmed the localization of the Sen loci. Thirty-three SNP markers linked to the Sen loci permitted the dissection of Sen alleles that increased or decreased resistance to wart. The alleles were inherited from both the resistant and susceptible parents