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The use of non-local Leucanthemum vulgare seeds in the course of restoration measures can no longer be detected several years after their application

Ecological restoration along roadside verges and on compensatory sites requires large-scale reintroductions of plants in form of seeds or seedlings; however, the genetic basis of seed or seedling sourcing is a controversial issue. Formerly, non-local seed sourcing of naturally occurring herbaceous species was common practice. Lately local provenancing got wide attention, and additional strategies are being recommended. All of these, however, raise the costs for restoration efforts. Here we test whether the earlier introduction of non-local seeds of Leucanthemum vulgare agg. in the course of ecological restoration can still be detected several years after the measure. The results are used to provide conservation recommendations for this widespread herbaceous insect-pollinated species. We analyzed the population genetic pattern (AFLP) of the ox-eye daisy in Central Germany on sites formerly restored with non-local seed sources (R) and compared these to the ones of indigenous populations (I). All populations of Leucanthemum vulgare agg. were genetically diverse and did not clearly distinguish between R and I sites. Furthermore, no clear evidence of distinct local genetic patterns was observed. Based on our results, we argue for the use of non-native seeds in the course of restoration measures for ox-eye daisies due to cost savings, but support the demand for a broader population genetic monitoring in order to put the entire system of seed provenance on a solid empirical basis.

Basic analysis of Pimpinella saxifraga

Pimpinella saxifraga analysis with treatment conditions eight or more years after restoration

Pimpinella saxifraga analysis without treatment conditions eight or more years after restoration

Genotypic and phenotypic distinctness of restored and indigenous populations of Pimpinella saxifraga eight or more years after restoration

Formerly, non-local seed sourcing of naturally occurring herbaceous species was the main strategy for ecological restoration in Germany. Prices for non-local seeds were significantly lower and large quantities of local seeds were unavailable. We here tested whether the genetic composition of non-local seeds (R) of Pimpinella saxifraga L. (Apiaceae) of former restoration projects can still be detected several years after application and whether it differs from the species' regional gene pool (I). A comparative population genetic analysis (AFLP) was conducted. In a common garden experiment phenological and morphological differences were investigated. We further simulated mowing to investigate, if treatments affect indigenous (I) and restored (R) populations differently. The population genetic analysis resulted in two large and quite distinct and diverse cluster that separated I- and R-site individuals, with some signatures of introgression from R to I. Three generative fitness parameters featured significant differences between individuals of the R- and I-sites. The genotypic persistence reduces the availability of niches for the local genotype and may eventually lead to genotypic competition or introgression. We therefore recommend to retain from the introduction of the species' non-local genotypes in the region to avoid genotypic competition and recommend to use the genetically diverse local genotypes for restoration purposes. Data collection time: 2011.09.01 until 2013.11.30 In a comparative approach, we tested whether the genetic makeup of the former non-local seed source use of Pimpinella saxifraga L. (Apiaceae) in restoration projects at sites in Central Germany several years after application (restoration between 1994 and 2004) differs from the species' regional gene pool. In a comparative approach, we compared genetic diversities and differentiations by using amplified fragment length polymorphisms (AFLPs). Phenological and morphological differences were analyzed in a common garden experiment in which we cultivated plants from all sites. For that we sampled seed and plant material in autumn 2011 of seven populations per I- and R-site. Of each individual of each study site 60 seeds were sown in a common garden experiment at the Universities nursery in Giessen (Germany) in spring 2012. The data collections of generative and vegetative morphological variation were measured two times per week in 2013 throughout the season.

Application of DNA marker systems to test for genetic imprints of habitat fragmentation in Juniperus communis L. on different spatial and temporal scales - Integration of scientific knowlege into conservation measures

Entwicklung molekularer Marker für Mehltau- und Gelbrostresistenz bei Weizen

Die gezielte Nutzung von Resistenzgenen wird durch Markierung erheblich erleichtert. In diesem Projekt werden 33 molekulare Marker (RAPD, AFLP, Mikrosatelliten) auf dem Chromosom 2 BL auf Kopplung mit dem Resistenzgen Yr5 gegen Gelbrost des Weizens untersucht und ein Abstand von etwa 10 cM erreicht. Zu unbekannten neuen Resistenzgenen gegen Echten Mehltau aus Triticum dicoccon und T. durum wurden mehrere gekoppelte Mikrosatelliten gefunden.

Development of Methods to Identify Foods Produced by Means of Genetic Engineering

In the near future food produced by means of genetic engineering will be commercially available in large scales. In most cases the genetic modification will not be detectable macroscopically, but only by molecular biological techniques. The scope of this proposal is to develop and evaluate methods for the identification of foods produced by genetic engineering. The conclusive identification of genetic modifications depends normally on the presence of the modified DNA and on the knowledge about the modified sequences. That is certainly a limitation for the development of detection methods since for many food items these prerequistes are not fulfilled. Nevertheless, there are many other foods still containing DNA for which the modified sequences are known. The project concentrates on such products, although other approaches will also be covered. Methods for conclusive identification are based on polymerase chain reaction (PCR) diagnostic methods and hybridization techniques using specific probes. In addition to the genetic modification itself the detection systems have to consider the effects of the food matrix and the nature of the organism. In parallel to the straightforward development of methods based on PCR and hybridization procedures other methods which have the potential to increase efficiency in routinely performed analysis will be investigated (detection of marker genes, development of multiplex primer systems, microtiter plate based sandwich-type DNA probe assay (PCR-ELISA), DNA biosensors). The proposal covers also methods which support or might substitute PCR/hybridization procedures in certain cases, like direct hybridization, isothermal Nucleic Acid Sequence based Amplification (NASBA) and self-sustained sequence replication (3SR) techniques for actively transcribed modified sequences, AFLP fingerprinting and protein diagnostic methods. The proposal combines 12 laboratories from 8 European countries.

Markergestuetzte Selektion bei der Zuechtung der Zuckerrueben

Entwicklung eines markergestuetzten Nachweissystems fuer die Resistenzgene gegen Rizomania und Cercospora aus Beta maritima und Identifikation von Genotypen mit einem minimalen Prozentanteil des unerwuenschten Genotypes der Beta maritima-Spenderlinie.

Warum blüht der Böhmische Enzian zu unterschiedlichen Zeiten? Eine populationsgenetische Analyse basierend auf den Hypothesen des Wiener Botanikers Richard Wettstein

Der Böhmische Enzian (Gentianella bohemica) ist eine endemische, vom Aussterben bedrohte Art der Böhmischen Masse, welche durch landwirtschaftliche Intensivierung oder Nutzungsaufgabe in der jüngeren Vergangenheit stark zurückgedrängt worden ist. Die auf extensiven Wiesen und Weiden vorkommende zweijährige Pflanze zeigt eine saisonale Differenzierung in früh- und spätblühende Sippen, wobei frühblühende Populationen nur noch aus dem niederösterreichischen Waldviertel bekannt sind. Im Rahmen des Projektes wird mittels DNA Fingerprint Technik untersucht, wie sich die genetische Struktur und Diversität der beiden phänologisch nicht überschneidenden Sippen über verschiedene Generationen hinweg unterscheiden. Ausgangspunkt ist die nun fast 120 Jahre alte und immer noch kontrovers diskutierte Hypothese des Wiener Botanikers und zeitweiligen Rektors der Universität Wien, Richard Wettstein, zur Entstehung früh- und spätblühender Sippen verschiedener Wiesenpflanzen. Entsprechende populationsgenetische Untersuchungen am Böhmischen Enzian sollen klären, in welchem Verhältnis die beiden Blüh-Sippen zueinander stehen; ob sie evolutionär eigenständige Linien bilden, die jeweils einen voneinander unabhängigen zweijährigen Rhythmus erkennen lassen; oder ob es einen genetischen Austausch zwischen diesen beiden Linien gibt. Die zu erwartenden populationsgenetischen Ergebnisse liefern zudem wertvolle Grundlagen für eine Bewertung der Überlebenschancen der Waldviertler Populationen von Gentianella bohemica sowie der möglichen Auswirkungen oder Erfolgsaussichten von Wiederansiedlungsversuchen. Darüber hinaus können sie bei der Auswahl geeigneter Populationen für Neuansiedlung oder Verstärkung von Populationen hilfreich sein.

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