Nutzung genetischer Ressourcen der Europäischen Wildrebe für die Züchtung von Mehltau- und Schwarzfäule-resistenten Reben

Zur Bekämpfung der Schwarzfäule werden im ökologischen Weinbau nach wie Kupfer- oder Schwefelpräparate eingesetzt. Als Alternative sollte das Potential der Europäischen Wildrebe (Vitis sylvestris) für die Resistenzzüchtung untersucht werden. Dies würde zum einen die natürliche Artbarriere respektieren und neue Resistenzquellen für eine nachhaltige Pyramidisierung erschließen. Grundlage war eine im Rahmen des BLE-Projekts „Überlebenssicherung der Wildrebe in den Rheinauen durch gezieltes in-situ Management“ im Botanischen Garten des KIT etablierte Sammlung von V. sylvestris, die nach derzeitigem Kenntnisstand die in Deutschland für diese Art noch vorhandene genetische Diversität vollständig abbildet. In dieser Sammlung waren Hinweise auf Resistenzen gegen die Rebenkrankheiten Falscher Mehltau, Echter Mehltau und Schwarzfäule entdeckt worden. Diese Population wurde sehr detailliert in Bezug auf Resistenz gegenüber Schwarzfäule, Falschem Mehltau, Echtem Mehltau, anatomischen und chemischen Merkmalen, und genetisch mit 5-10 hochauflösenden Mikrosatellitenmarkern je Chromosom kartiert. Für zwei interessante sylvestris Genotypen konnten umfangreiche Kreuzungspopulationen mit vinifera erzeugt werden. Weiterhin wurden für die Schwarzfäule viele Aspekte der Infektion aufgeklärt. So konnte gezeigt werden, dass während der biotrophen Phase Pektine aus der Zellwand des Wirts als Nahrungsquelle genutzt werden, und dass die bessere Altersresistenz einiger sylvestris Genotypen mit Modifikationen des Pektins zusammenhängt und ein interessantes Ziel für die Resistenzzüchtung darstellen könnten. Weiterhin konnten für zwei Beispiele von nichtamerikanischen Wildreben molekulare Mechanismen aufgezeigt werden, die zu einer wirkungsvolleren basalen Immunität gegen Falschen oder Echten Mehltau führen. Das Projekt legt damit die Grundlage für die Erschließung unserer heimischen Wildrebe V. sylvestris als genetische Ressource für den nachhaltigen Weinbau der Zukunft

Monitoring of total contents of copper in organically and conventionally managed soils. Part 1: Study plan and preliminary sampling of copper and other anthropogenic induced heavy metal contents in vineyard soils

The project aims to develop a survey designed for the representative assessment of copper contents in vineyard soils. The method development for the sampling of adequate monitoring areas is based on a preliminary survey of load distribution as well as on exposure assessment on selected areas of some typical vinery sites in Rheinland-Pfalz, differently managed and with different use history. Additionally to the sampling of selected areas, which reflects the spectrum of the load situation in viticulture, chemical quantitative analysis of soil samples collected from areas of known mode of cultivation and history followed by biological standard tests will be conducted. Obtained findings will serve for further method development, for preselection of adequate monitoring areas and for first indications of hazard potential. The project is a prerequisite for the performance of the long-term study “Development of current data of effects of copper contents in organic soils in viticulture, pomiculture and hopculture on soil life in terms of the strategypaper concerning further copper application in agriculture, especially in organic farming.

Neue molekulare Marker für die Rebenzüchtung zur gezielten Pyramidisierung der Resistenz gegenüber dem Falschen Mehltau (Plasmopara viticola)

Zusammenfassung Molekulare Marker eröffnen neue Möglichkeiten für eine effiziente, zielgerichtete und beschleunigte Züchtung neuer Rebsorten. Von besonderem Interesse sind sie beispielsweise im Hinblick auf die gezielte Kombination verschiedener Abwehrmechanismen in einer Pflanze (Pyramidisierung) zur Etablierung einer hohen und dauerhaften Resistenz. Zu diesem Zweck sollen neue Molekulare Marker für die aus der asiatischen Wildart Vitis amurensis stammenden Plasmopara-Resistenzmechanismen entwickelt und für die Züchtung nutzbar gemacht werden. Stichwörter: Plasmopara viticola; Resistenzzüchtung; Molekulare Marker; Blattscheibentest   Abstract Molecular markers are a superior tool to make grapevine breeding more efficient and faster. A matter of particular interest is to identify the combination of different defence mechanisms in one plant to select durable highly resistant plants. For this case we are developing new molecular markers to detect the resistance mechanisms out of the Asian wild type Vitis amurensis against downy mildew (Plasmopara viticola) to use them in our marker based breeding program. Keywords:Plasmopara viticola; resistance breeding; molecular marker; leaf disc tes

Quantitative trait loci affecting pathogen resistance and ripening of grapevines

Grapevines (Vitis vinifera L.) form the basis of viticulture, and are susceptible to diseases such as downy mildew (Plasmopara viticola) and powdery mildew (Erysiphe necator). Therefore, successful viticulture programs require the use of pesticides. Breeding for resistance is the only eco-friendly solution. Marker-assisted selection is currently widely used for grapevine breeding. Consequently, traits of interest must be tagged with molecular markers linked to quantitative trait loci (QTL). We herein present our findings regarding genetic mapping and QTL analysis of resistance to downy and powdery mildew diseases in the progenies of the GF.GA-47-42 (‘Bacchus’ × ‘Seyval’) × ‘Villard blanc’ cross. Simple sequence repeats and single nucleotide polymorphisms of 151 individuals were analyzed. A map consisting of 543 loci was screened for QTL analyses based on phenotypic variations observed in plants grown in the field or under controlled conditions. A major QTL for downy mildew resistance was detected on chromosome 18. For powdery mildew resistance, a QTL was identified on chromosome 15. This QTL was replaced by a novel QTL on chromosome 18 in 2003 (abnormally high temperatures) and 2004. Subsequently, both QTLs functioned together. Additionally, variations in the timing of the onset of veraison, which is a crucial step during grape ripening, were studied to identify genomic regions affecting this trait. A major QTL was detected on linkage group 16, which was supplemented by a minor QTL on linkage group 18. This study provides useful information regarding novel QTL-linked markers relevant for the breeding of disease-resistant grapevines adapted to current climatic conditions

Marker-assisted pyramiding of resistance loci to grape downy mildew

O objetivo deste trabalho foi o emprego da seleção assistida por marcadores moleculares para piramidação dos locos de resistência Rpv1 e Rpv3.1, em videira (Vitis vinifera), e avaliar o nível de resistência conferido por eles contra isolados brasileiros de míldio (Plasmopara viticola). Uma progênie de 23 plantas, com segregação para os dois locos de resistência, foi obtida do cruzamento entre os genótipos Gf2000-305-122 e Gf.Ga-52-42. A progênie foi genotipada com quatro marcadores microssatélites e fenotipada, quanto à resistência a P. viticola, em discos foliares. A análise molecular identificou seis plantas com os locos Rpv1 e Rpv3.1 piramidados. Plantas com os locos Rpv1 + Rpv3.1, Rpv3.1 e Rpv1 apresentaram 12,8, 30,0 e 33,1 esporangióforos por disco foliar, respectivamente. As plantas sem locos de resistência tiveram esporulação densa. A análise fenotípica da expressão dos dois locos piramidados foi confirmada somente para quatro plantas que mostraram o maior nível de resistência, isto é, média de 1.8 esporangióforos. Desenvolveu-se uma metodologia de alto rendimento para a piramidação dos locos Rpv1 e Rpv3.1, que confirmou o aumento da resistência a P. viticola. O material genético superior selecionado apresenta alta resistência ao míldio e elevado potencial enológico para o melhoramento da videira no Brasil.The objective of this work was to use a marker-assisted selection for pyramiding the resistance loci Rpv1 and Rpv3.1 in grapevine (Vitis vinifera), and to evaluate their conferred resistance against Brazilian downy mildew (Plasmopara viticola) isolates. A progeny of 23 plants, segregating for the two resistance loci, was obtained by the cross between the Gf 2000-305-122 and Gf.Ga-52-42 genotypes. The progeny was genotyped with four microsatellite markers and phenotyped for resistance to P. viticola using a bioassay with leaf discs. Six plants containing the Rpv1 and Rpv3.1 pyramided loci were identified by the molecular analysis. Plants harboring the Rpv1 + Rpv3.1, Rpv3.1, and Rpv1 loci showed 12.8, 30.0, and 33.1 sporangiophores per leaf disc, respectively. Plants with no resistance loci showed a dense sporulation. The phenotypic analysis of the expression of the two pyramided loci was only confirmed for four plants that showed the highest resistance level, i.e., mean value of 1.8 sporangiophores. A high-throughput method for pyramiding the Rpv1 and Rpv3.1 loci was developed, which confirmed the increased resistance to P. viticola. The selected elite genetic material shows a high resistance to downy mildew and elevated enological potential for grapevine breeding in Brazil