Züchtungsforschung für den Ökologischen Landbau an der Landessaatzuchtanstalt Hohenheim – Roggen, Triticale und Sonnenblumen

Breeding is an important tool to develop varieties with an optimal adaptation to organic farming. Several important traits are not covered by conventional research and breeding. At the State Plant Breeding Institute we are presently working on (1) resistance of rye to ergot (Claviceps purpurea), (2) nitrogen(N)-use efficiency in triticale, and (3) protein content of sunflower. The inheritance of these complex traits is quantitative. They are analysed in replicated field experiments at two locations in three years at several organic farms in Germany. For testing ergot resistance in rye, 68 populations, 250 full-sib families, 64 lines, and their 90 testcrosses were inoculated at mid-flowering by a spore suspension. All four material groups displayed significant (P<0.01) genotypic variation, indicating that a resistance selection should be feasible. N-use efficiency of 64 triticale genotypes was evaluated at two different N-levels. Significant genotypic variation was found, which is a prerequisite for breeding for improved N-use efficiency. To increase protein content, the 230 sunflower inbred lines investigated showed a high variation for protein and oil content. Only a small negative correlation between both traits was found. Thus, it should be possible to breed lines with high protein and high oil contents

Verminderung von Alkaloiden in der Nahrungskette durch die züchterische Verbesserung der Mutterkorn-Resistenz von Winterroggen

Rye as an outcrossing crop is highly susceptible to ergot infection caused by Claviceps purpurea. It is ecologically the best solution to avoid the infection already in the field by growing resistant varieties. Aim of our study is the analysis of inheritance of self-fertile rye material for ergot resistance and alcaloid content. Sixty CMS inbred lines and their 90 CMS crosses were tested in pollen-isolated fields in three environ-ments under the conditions of Ecological Farming by artificial inoculation. The sclerotia weight per head was evaluated as resistance trait. Both, CMS lines and testcrosses showed significant genotypic differences at the individual environments. Correlation between both groups was significant (r=0,6-0,7; P=0,01). The alcaloid contents and the alcaloid spectra of 25 CMS lines revealed no genotypic difference. Breeding of self-fertile rye for a higher resistance to ergot should be successful on the long run

Multi-parental QTL mapping of resistance to white spot of maize (Zea mays) in southern Brazil and relationship to QTLs of other foliar diseases

Maize white spot (MWS) is one of the most important foliar diseases in Brazil causing significant yield losses. Breeding genotypes with MWS resistance is the most sustainable alternative for managing such losses; however, their genetic control is poorly understood. Our objectives were to identify genomic regions controlling MWS resistance and to explore the presence of common regions controlling resistance to MWS, grey leaf spot (GLS) and northern corn leaf blight (NCLB). We performed a multi-parental QTL mapping for MWS and GLS resistance with a total of 474 testcrosses and phenotypic data collected in southern Brazil. Six QTLs for MWS resistance on bins 1.03, 1.04, 6.02, 8.05, 1.03, and 10.06 were detected. These findings were compared with previously reported QTLs for NCLB in the same populations, and a common QTL region (bin 8.05) controlling MWS and NCLB resistances was identified. Our findings contribute to a better understanding of MWS resistance by revealing three QTLs (bin 6.02, 1.03, and 10.06), to the best of our knowledge, not yet described in the literature, that are valuable for improving MWS resistance and one promising candidate region for multiple disease resistance.Fil: Kistner, María Belén. Universidad de Hohenheim; Alemania. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires; ArgentinaFil: Galiano Carneiro, Ana Luísa. Kleinwanzlebener Saatzucht; Alemania. Universidad de Hohenheim; AlemaniaFil: Kessel, Bettina. Kleinwanzlebener Saatzucht; AlemaniaFil: Presterl, Thomas. Kleinwanzlebener Saatzucht; AlemaniaFil: Miedaner, Thomas. Universidad de Hohenheim; Alemani

Multi-parent QTL mapping reveals stable QTL conferring resistance to Gibberella ear rot in maize

Maize production is on risk by Gibberella ear rot (GER) caused by Fusarium graminearum. This is one of the most important ear rot diseases in temperate zones as it leads to yield losses and production of harmful mycotoxins. We investigated, for the first time, the potential use of Brazilian tropical maize to increase resistance levels to GER in temperate European flint germplasm by analyzing six interconnected biparental populations. We assessed GER symptoms in Brazil and in Europe in up to six environments (= location × year combinations) during the growing seasons of 2018 and 2019. We conducted multi-parent QTL and biparental QTL mapping, and identified four QTLs with additive gene action, each explaining 5.4 to 21.8% of the total genotypic variance for GER resistance. Among them, QTL q1 was stable across test environments, populations, and between inbred lines and testcrosses. The accuracies of genomic prediction ranged from 0.50 to 0.59 depending on the resistance donor and prediction model. Jointly, our study reveals the potential use of Brazilian resistance sources to increase GER resistance levels by genomics-assisted breeding.EEA PergaminoFil: Galiano-Carneiro, Ana L. University of Hohenheim. State Plant Breeding Institute; AlemaniaFil: Galiano-Carneiro, Ana L. Kleinwanzlebener Saatzucht (KWS) SAAT SE & Co. KGaA; AlemaniaFil: Kessel, Bettina. Kleinwanzlebener Saatzucht (KWS) SAAT SE & Co. KGaA; AlemaniaFil: Presterl, Thomas. Kleinwanzlebener Saatzucht (KWS) SAAT SE & Co. KGaA; AlemaniaFil: Gaikpa, David Sewordor. University of Hohenheim. State Plant Breeding Institute; AlemaniaFil: Kistner, María Belén. University of Hohenheim. State Plant Breeding Institute; AlemaniaFil: Kistner, María Belén. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Pergamino. Departamento de Maíz; ArgentinaFil: Kistner, María Belén. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Miedaner, Thomas. University of Hohenheim. State Plant Breeding Institute; Alemani

Genomics-assisted breeding for quantitative disease resistances in small-grain cereals and maize

Generating genomics-driven knowledge opens a way to accelerate the resistance breeding process by family or population mapping and genomic selection. Important prerequisites are large populations that are genomically analyzed by medium- to high-density marker arrays and extensive phenotyping across locations and years of the same populations. The latter is important to train a genomic model that is used to predict genomic estimated breeding values of phenotypically untested genotypes. After reviewing the specific features of quantitative resistances and the basic genomic techniques, the possibilities for genomics-assisted breeding are evaluated for six pathosystems with hemi-biotrophic fungi: Small-grain cereals/Fusarium head blight (FHB), wheat/Septoria tritici blotch (STB) and Septoria nodorum blotch (SNB), maize/Gibberella ear rot (GER) and Fusarium ear rot (FER), maize/Northern corn leaf blight (NCLB). Typically, all quantitative disease resistances are caused by hundreds of QTL scattered across the whole genome, but often available in hotspots as exemplified for NCLB resistance in maize. Because all crops are su ering from many diseases, multi-disease resistance (MDR) is an attractive aim that can be selected by specific MDR QTL. Finally, the integration of genomic data in the breeding process for introgression of genetic resources and for the improvement within elite materials is discussed.Generar conocimiento impulsado por la genómica abre una manera de acelerar la reproducción de resistencias proceso por mapeo de familias o poblaciones y selección genómica. Los requisitos previos importantes son grandes poblaciones que se analizan genómicamente mediante matrices de marcadores de densidad media a alta y extensas fenotipado en ubicaciones y años de las mismas poblaciones. Esto último es importante para capacitar a un modelo genómico que se utiliza para predecir valores genómicos estimados de reproducción de fenotípicamente no probados genotipos. Después de revisar las características específicas de las resistencias cuantitativas y las características genómicas básicas técnicas, las posibilidades de reproducción asistida por genómica se evalúan para seis patosistemas con hongos hemi-biotróficos: cereales de grano pequeño / tizón de la cabeza por Fusarium (FHB), trigo / mancha de Septoria tritici (STB) y la mancha de Septoria nodorum (SNB), pudrición de la mazorca de maíz / Gibberella (GER) y pudrición de la mazorca por Fusarium (FER), maíz / tizón de la hoja del maíz del norte (NCLB). Por lo general, todas las resistencias cuantitativas a las enfermedades son causadas por cientos de QTL esparcidos por todo el genoma, pero a menudo disponibles en hotspots como se ejemplifica para Resistencia a NCLB en maíz. Debido a que todos los cultivos padecen muchas enfermedades, la resistencia a múltiples enfermedades (MDR) es un objetivo atractivo que puede seleccionarse mediante MDR QTL específico. Finalmente, la integración de datos genómicos en el proceso de mejoramiento para la introgresión de recursos genéticos y para la mejora.Estación Experimental Agropecuaria PergaminoFil: Miedaner, Thomas. University of Hohenheim. State Plant Breeding Institute; AlemaniaFil: Galiano-Carneiro Boeven, Ana Luisa. University of Hohenheim. State Plant Breeding Institute; AlemaniaFil: Galiano-Carneiro Boeven, Ana Luisa. Kleinwanzlebener Saatzucht (KWS) SAAT SE & Co. KGaA; AlemaniaFil: Sewodor Gaikpa, David. University of Hohenheim. State Plant Breeding Institute; AlemaniaFil: Kistner, Maria Belén. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Pergamino; ArgentinaFil: Kistner, María Belén. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Kistner, María Belén. University of Hohenheim. State Plant Breeding Institute; AlemaniaFil: Grote, Cathérine Pauline. University of Hohenheim. State Plant Breeding Institute; Alemani

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

Does acute passive stretching increase muscle length in children with cerebral palsy?

This article has been made available through the Brunel Open Access Publishing Fund. Copyright @ The Authors. This article is distributed under the terms of the Creative Commons Attribution Noncommercial License which permits any noncommercial use, distribution, and reproduction in anymedium, provided the original author(s) and the source are credited.Background: Children with spastic cerebral palsy experience increased muscle stiffness and reduced muscle length, which may prevent elongation of the muscle during stretch. Stretching performed either by the clinician, or children themselves is used as a treatment modality to increase/maintain joint range of motion. It is not clear whether the associated increases in muscle–tendon unit length are due to increases in muscle or tendon length. The purpose was to determine whether alterations in ankle range of motion in response to acute stretching were accompanied by increases in muscle length, and whether any effects would be dependent upon stretch technique. Methods: Eight children (6–14 y) with cerebral palsy received a passive dorsiflexion stretch for 5 × 20 s to each leg, which was applied by a physiotherapist or the children themselves. Maximum dorsiflexion angle, medial gastrocnemius muscle and fascicle lengths, and Achilles tendon length were calculated at a reference angle of 10° plantarflexion, and at maximum dorsiflexion in the pre- and post-stretch trials. Findings: All variables were significantly greater during pre- and post-stretch trials compared to the resting angle, and were independent of stretch technique. There was an approximate 10° increase in maximum dorsiflexion post-stretch, and this was accounted for by elongation of both muscle (0.8 cm) and tendon (1.0 cm). Muscle fascicle length increased significantly (0.6 cm) from pre- to post-stretch. Interpretation: The results provide evidence that commonly used stretching techniques can increase overall muscle, and fascicle lengths immediately post-stretch in children with cerebral palsy