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Sicherung der genetischen Vielfalt von für die Unterlagenzüchtung relevanten Wildformen der Gattung Vitis

Eine hohe Resistenz gegen Bodenpathogene, gute Standortanpassung und Veredlungsaffinität sind die entscheidenden Merkmale von Unterlagen. Bei der Pathogenresistenz ist bei Reben die Widerstandsfähigkeit gegen die Reblaus Daktulosphaira vitifoiae essentiell, da die europäische Kulturrebe Vitis vinifera L über keinerlei Resistenzen verfügt und nur an wenigen Standorten ein wurzelechter Anbau möglich ist. Amerikanische Wildformen mit solchen Reblausresistenzen sind daher in der Unterlagenzüchtung von großer Bedeutung. Die langfristige Sicherung solcher Genotypen ist daher eine Voraussetzung für spätere Züchtungsarbeiten zur Erstellung neuer besserer Unterlagen. Daneben spielt auch die Standortanpassung eine wichtige Rolle. Vitis berlandieri ist hier am wichtigsten, da sie als einzige Art über eine hohe Kalkverträglichkeit verfügt und die Mehrheit der deutschen und europäischen Weinbaustandorte durch hohe Kalkgehalte im Boden charakterisiert sind. Kalkempfindliche Arten leiden unter Kalkchlorose mit stark vermindertem Wuchs. Aufgrund begrenzter Verfügbarkeit wurden jedoch nur wenige Pflanzen der Art in der Unterlagenzüchtung verwendet und damit nur ein Teil des Potentials der Art genutzt. In einem gemeinsamen Projekt mit dem United States Department for Agriculture wurden daher im September 2005 im ursprünglichen Verbreitungsgebiet der Art in Zentraltexas Samen von Wildformen gesammelt und die Hälfte davon in Geisenheim zur Keimung gebracht und ausgepflanzt. Derzeit werden mehr als 5000 Pflanzen in der in vivo Erhaltung. In den kommenden Jahren werden diese hinsichtlich ihrer relevanten Eigenschaften phänotypisch charakterisiert und in einem späteren Stadium auch genotypisiert, um für weitere Kreuzungs- und Selektionsarbeiten nutzbares material zu identifizieren.

Züchtung von Rebunterlagen mit hoher Reblausfestigkeit und Anpassung an Trockenheit und Kalk-Chlorose

Eine hohe Resistenz gegen Bodenpathogene, gute Standortanpassung und Veredlungsaffinität sind die entscheidenden Merkmale von Unterlagen. Bei der Pathogenresistenz ist bei Reben die Widerstandsfähigkeit gegen die Reblaus Daktulosphaira vitifoiae essentiell, da die europäische Kulturrebe Vitis vinifera L über keinerlei Resistenzen verfügt und nur an wenigen Standorten ein wurzelechter Anbau möglich ist. Klimaveränderungen erfordern neue Unterlagen mit hoher Reblausfestigkeit und besserer Standortanpassung. Aufgrund der derzeitigen Szenarien werden sowohl Trockenresistenz als auch Toleranz gegen hohe Kalkgehalte insbesondere in Verbindung mit hohem Bodenwassergehalte zukünftig von Bedeutung sein. Hierfür werden entsprechende Kreuzungen vorgenommen, die Sämlinge aufgezogen, auf ihre Reblausfestigkeit getestet und anschießend Prüfungen der Wurzelungs- und Veredlungsfähigkeit vorgenommen. Anschließend wird die Witterungs- und Bodenanpassung der Zuchtstämme insbesondere auf Trocken- und Kalkstandorten untersucht. Ziel ist die Entwicklung verschiedener Unteralgen, die eine vollständige Reblausresistenz mit hohen Trockenheits- und/oder Kalktoleranz kombinieren.

Barley dwarfs acting big in agronomy. Identification of genes and characterization of proteins involved in dwarfism, lodging resistance and crop yield

Barley (Hordeum vulgare) is an important cereal grain which serves as major animal fodder crop as well as basis for malt beverages or staple food. Currently barley is ranked fourth in terms of quantity of cereal crops produced worldwide. In times of a constantly growing world population in conjunction with an unforeseeable climate change and groundwater depletion, the accumulation of knowledge concerning cereal growth and rate of yield gain is important. The Nordic Genetic Resource Center holds a major collection of barley mutants produced by irradiation or chemical treatment. One phenotypic group of barley varieties are dwarf mutants (erectoides, brachytic, semidwarf, uzu). They are characterized by a compact spike and high rate of yield while the straw is short and stiff, enhancing the lodging resistance of the plant. Obviously they are of applied interest, but they are also of scientific interest as virtually nothing is known about the genes behind the development of plant dwarfism. The aim of this project is to identify and isolate the genes carrying the mutations by using state of the art techniques for gene cloning at the Carlsberg Laboratory. The identified genes will be connected with the mutant phenotype to reveal the gene function in general. One or two genes will be overexpressed and the resulting recombinant proteins will be biochemically and structurally characterized. The insights how the mutation effects the protein will display the protein function in particular. Identified genes and their mutant alleles will be tested in the barley breeding program of the Carlsberg brewery.

Simulated field environment with combined salt and drought stresses as a platform for phenotyping plant tolerance to salinity

Salinity occurs often simultaneously with drought stress. Therefore, breeding for tolerance to combined both stresses can contribute significantly to crop yield. However, classical selection in salinity has generally been unsuccessful, partly due to high variability of salt stress resulting from the different salinity and drought status. Unfortunately, the use of unrealistic stress protocols for mimicking salinity and drought stress is the norm rather than the exception in biotechnological studies. Therefore, the great challenge is to gain knowledge required to develop plants with enhanced tolerance to field conditions. Our overall hypothesis is that a realistic stress protocol simulating a field environment with combined salt and drought stress as a platform for precision phenotyping of plant tolerance to salinity may solve this problem. This study will demonstrate that highly managed stress environments can be created and key traits of plants can be characterised by using advanced non-destructive sensors that are able to identify relevant traits of plants.

Identification. cloning and functional characterization of genes related to fire blight resistance in Malus x robusta (D-A-CH/LAV)

The fire blight disease caused by the bacterium Erwinia amylovora, is currently the major constraint for apple production in several European countries including Germany and Switzerland. In recent years several infections occurred which have led to costs in the tens of millions Euros. The antibiotic Streptomycin (Plantomycin®), which is the only effective plant protective agent, can only be applied under particular restrictions. Planting of fire blight resistant cultivars seems to be the most promising solution, which is environmental and producer friendly. Unfortunately, the available fire blight resistant apple cultivars are non-competitive on the market, because of their inferior fruit quality. The improvement of established cultivars like 'Golden Delicious' or 'Gala' using classical breeding strategies is impossible because apple is self-incompatible and heterozygous. Each offspring of a sexual cross between such a cultivar and a resistant genotype will be genetically different to each of the parents. Linkage drag coming from the resistant led often to a decrease in fruit quality. Several crosses with cultivars of good quality are necessary to remove most of the unwanted traits and the result will be a completely new cultivar. Breeding of such a new apple cultivar is time consuming and in the end it is not clear, whether the new cultivar will be accepted by consumers and growers or not. Under these premises, the introduction of a specific gene into a particular cultivar which already has all qualities necessary, except the trait in question, is attractive. The recombinant DNA-technology offers the most promising strategy to solve the problem of fire blight by using Malus own genes without the need to change the popular cultivars. The development of cisgenic plants seems to be a realistic and successful strategy. Cisgenic plants contain only genes, which originates from crossable species and not from outside of the primary genepool. They are therefore comparable to classical bred plants and expected to be acceptable by consumers and growers. The methodology to produce such a durable resistant cisgenic apple cultivar has already been established, but an apple fire blight resistance gene (or linked gene set) is still needed. Recently a strong Fieblight resistance has been identified on chromosome 3 of the apple hybrid Malus x robusta 5. This project focuses on the isolation of the gene(s) inducing the resistance of M. x robusta 5 and its cloning into the susceptible cultivar Gala. Furthermore the interaction of this (or these) genes products with gene products of the pathogen will be studied so to understand the interaction mechanisms and therefore evaluate the durability of the resistance.

Modellierung geeigneter Wiederansiedelungshabitate für die Flussperlmuschel (Margaritifera margaritifera) -Methodenentwicklung (FLUP-Habitat)

Die Flussperlmuschel (Margaritifera margaritifera) ist als vom Aussterben bedrohte Art einzustufen. Die Nachzucht der Muschel gelang in den letzten Jahren mittels einer eigens errichteten Nachzuchtstation jedoch durchaus sehr erfolgreich. Um für die Wiederansiedelung der Flussperlmuschel in Fließgewässern zu gewährleisten gilt es vorab geeignete Lebensraumbedingungen zu finden. Dabei ist die Habitatmodellierung als geeignetes Instrument für eine Bewertung bzw. eine Vorauswahl anzusehen. Diese Modellierung beruht auf Eingangsparametern, die in intakten Flussperlmuschelgewässern erhoben werden müssen. Solche intakten Gewässer mit reproduktiven Flussperlmuschelpopulationen existieren aktuell nur noch in Nordeuropa (z. B. Schweden, Finnland, Norwegen) und in einem deutschen Heidebach, der Lutter, in der ein umfangreiches, das gesamte Einzugsgebiet umfassendes Sanierungs- und Wiederansiedelungsprojekt sehr erfolgreich umgesetzt wurde. Ziel des Projektes ist es, in verschiedenen österreichischen Gewässern jene (Lebensraum-)Parameter zu erfassen, welche von der Flussperlmuschel genutzt bzw. auch nicht genutzt werden, um funktionale Zusammenhänge für ein zukünftiges Management zu erkennen, bzw. auch jene Nutzungskurven abzuleiten, die für mögliche hydraulische Modellanwendungen zur Habitatevaluierung benötigt werden. Um dieses Ziel zu Erreichen wird eine Charakterisierung der Gewässermorphologie mittels tachymetrischer Vermessung von genutzten und nicht genutzten Gewässerprofilen durchgeführt als Grundlage für die eindimensionale numerische Modellierung (HEC-RAS). Weiters werden Kornverteilungskurven mittels volumetrischer Beprobung aus Deck- und Unterschicht erstellt mit einer Bestimmung der Feinsedimentanteile (kleiner als 0,063 mm, kleiner als 0,125 mm, kleiner als 0,250 mm) durchgeführt.

Internationales Graduiertenkolleg (IRTG) 1070: Modellierung von Stoffflüssen und Produktionssystemen für eine nachhaltige Ressourcennutzung in intensiven Acker- und Gemüsebausystemen in der nordchinesischen Tiefebene' (769), SP 2.2 QTL analysis and optimization of breeding schemes for improved nitrogen-use efficiency of maize and wheat for sustainable cropping systems in the North China Plain

In China, agriculture needs to be intensified by increasing the productivity per unit land. However, the possibility to improve yield by further increasing the amounts of input is very limited due to already very high input amounts of fertilizers and irrigation water in the present cropping system. Hence, the development and characterization of improved varieties, especially with regard to traits of utmost importance for sustainable resource use, such as nitrogen- (NUE) and water-use efficiency (WUE), is crucial for a sustainable agriculture in the North China Plain. The decision about the requirement of one common or two separate breeding programs for developing varieties adapted to low and high N fertilization strongly depends on an appropriate estimation of the correlation between yield at different fertilization levels. Therefore, maize and wheat varieties are evaluated in multiple locations in the North China Plain. Adopting novel breeding approaches based on doubled haploids (DH) can speed up the process of developing new varieties substantially and rapidly provides suitable cultivars for new cropping systems. Therefore, optimum breeding strategies for maize breeding are modeled and simulated to optimize alternative breeding schemes with respect to the optimum allocation of test resources using different optimization criteria. Modeling of production systems and material flows is a powerful tool to increase sustainable resource use by identifying cropping systems, which combine reduced inputs with high yields. However, an appropriate model requires knowledge about the genetics of crop growth and yield and its interaction with environmental factors. Therefore, maize and wheat populations developed by the Chinese partners in the first project phase are phenotyped in multi-location field trials and genotyped with molecular markers to map quantitative trait loci (QTL) for NUE.

Influence of landscape change on population structure of black-backed Swamphen (Porphyrio indicus) in Java island, Indonesia

Landscape changes may influence population persistence and genetic diversity of black-backed Swamphen (Porphyrio indicus) in Java Island. The changes occurred rapidly, particularly in the coastal area, due to human population pressure. It may affect negatively the quality and compactness of natural ecosystems, particularly wetlands. In turn, it may lead to a reduction of critical resources and impair individual movement. The effect will be severe particularly for wetland-breeding specialist with poor flight capability like in black-backed Swamphen. It is reasonable that some local ornithologist warn about the bird species persistence. Limited information on its behavior and biology make the conservation efforts even more difficult. The species cryptic behavior impedes direct observation for habitat and movement studies, whereas fraught classification makes information on their population size and distribution debatable. Limited reliable information on these aspects may pose an obstacle to conserve their natural population in a rapidly changed environment. Information on population structure and the individual movement between sub populations are central for species conservation in a changing landscape. The project will address some important questions about the effect of the changes on population isolation and its suspected causes, rate of dispersal necessary to maintain genetic diversity, and biased dispersal. A new approach combining molecular genetic and GIS techniques may provide such information and may overcome the lack of direct observations. As guidance for data collection and analysis, general research question is defined as follows: 'How do landscape feature influence individual movement between population of Porphyrio indicus in Java Island ?' Following it, some sub questions may arise: What are the landscape structure and composition in past and recent years? How populations are spatially structured in recent and past years? Is there any evidence of individual exchange between subpopulations? Which landscape features are supposed to facilitate and inhibit individual exchange? Which landscape features do explain population structure better? Several work steps are planned: field work for collecting genetic material, laboratory work for isolation-amplification-analysis of DNA fragments, and desk work for landscape analysis. Raw genetic data of and landscape features will be combined to address the research questions.

Sonderforschungsbereich (SFB) 564: Nachhaltige Landnutzung und ländliche Entwicklung in Bergregionen Südostasiens; Sustainable Land Use and Rural Development in Mountainous Regions of Southeast Asia, D 2.3: Efficiency of smallholder animal husbandry depending on intensity of management and genetic potential of livestock - Community driven breeding programmes: Optimisation of planning procedures

In the mountainous regions of North Vietnam, smallholder farmers try to sustain and improve their livelihoods under conditions of growing population density and land pressure. Livestock husbandry appears as major development opportunity for them. Yet, 'mountainous regions' are heterogeneous, comprising areas near town with favourable access to markets and infrastructure but higher land pressure and remote areas, disadvantaged concerning market and infrastructure access but disposing of larger cropping and pasture areas. Low and unsteady resource availability in marginal areas limits the possibilities for intensification of livestock production. One solution is to increase production efficiency through improved resource utilisation. In animal production this can be realised through the development of sustainable livestock breeding and management programmes, using genotypes with high productive adaptability. Such programmes will have different structures depending on short- and medium-term resource availability, production objectives and production intensity of respective smallholder production systems.Based on the results of phase 1 and 2, D2.3 focuses on planning procedures for livestock breeding and management programmes for four combinations of production systems and species/genotypes, namely production of lean pork with exotic higher-yielding breeds in demand-driven systems, production of branded pork from local Ban pigs including remote, resource-driven pig producers, production of beef in farming systems of different scale, organisational set-up and remoteness, and production of goat meat as niche product in systems in transition. The four programmes will respond to the large heterogeneity of smallholder production systems in the project area. In fulfilment of its research objectives, D2.3 relies on cooperation with sub-projects E4.1 (Product marketing) concerning the design of a pork marketing and quality control system in the frame of village breeding and pork marketing programmes, G1.2 (Innovations and sustainability strategies) and C4.1 (Land use modelling) on integrated modelling concerning the identification of most sustainable development paths for farms of different production intensity, scale, organisational set-up and remoteness, F2.3 (Livelihood risks) for characterisation of smallholder farms using key indicator regarding adoption of technologies in livestock husbandry, A1.3 (Participatory research) on adoption of optimised breeding strategies by farmers, and D5.2 (Aquaculture) on conflicts and complementarities in the use of feed resources for investigated livestock species and fish/aquaculture.

Internationales Graduiertenkolleg (IRTG) 1070: Modellierung von Stoffflüssen und Produktionssystemen für eine nachhaltige Ressourcennutzung in intensiven Acker- und Gemüsebausystemen in der nordchinesischen Tiefebene' (769), SP 3.1 Economic analysis on the effects of management and policy measures aiming at a reduction of the environmental burden from high-level agricultural production in the North China Plain

In the second phase of subproject 3.1 is envisaged to model representative farms. The models will be structured in a way that not only the production but also the material balances can be represented. In particular the nitrogen balance, the carbon balance and the water balance will be incorporated. Gas and particulate matter emissions can be considered as well, as far as there are sufficient data available. The modelling aims at integrating on farm level all baseline data surveyed in other sub-projects and at quantifying and valuating at farm level the already worked out management measures for reducing environmental burden while increasing production efficiency. The focus will be on measures for reducing nitrogen fertilisation, the interrelation between management activities and carbon/nitrogen balance, effects of nitrogen deposition on the operational nutrient management, water efficiency, etc. Another part for the impact analysis shall be the extent to which cropping practices elaborated in other sub-projects can be alternatives for the prevailing wheat-maize-rotation. Thereby cotton, groundnuts, soybeans, vegetables, and row intercropping are to be analysed and valued on farm level. Furthermore, the sub-project shall provide other sub-projects with indicators which are necessary in order to optimise breeding and management programmes under consideration of economic factors. Another aim of the sub-project is to carry out economic impact analyses of possible policy measures. To do so, realistic concepts of the Chinese agricultural policy as e.g. a reduction of the subsidies on means of production, in particular on nitrogen, water, etc. and their possible impact on quantities produced, input quantities applied, nutrient and water efficiency, income and other criteria are to be investigated. Furthermore, the influence of stages of an increasing mechanisation on production, income and structural changes can be investigated. Finally, open questions and approaches for further research will be derived through a sensitivity analysis.

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