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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.

Conservation Biology of Declining Grassland Species: Experimental Analysis of Population Processes

In the last decades many plant species have experienced a dramatic decline in the number of populations and the remaining populations are frequently small and isolated from each other. Environmental stochasticity and genetic erosion pose considerable threats to small and isolated plant populations. Successful management of declining species to conserve plant biodiversity requires an understanding of both demographic and genetic processes at the population level and of their importance for local extinctions. The first aim of our project is to analyze the mechanisms driving the population dynamics of plant species in decline. We will investigate the relationship between environmental factors, variability of demographic parameters, population size, and risk of extinction in several short-lived grassland species. All demographic data will be integrated into stochastic matrix population models to identify critical transitions in the life cycle and estimate critical population sizes. Part of the project is a continuation of demographic studies with Gentianella germanica. This offers the chance to obtain long-term estimates of the temporal and spatial variability of demographic transition rates. They will be integrated into models to study minimum data requirements for reliable predictions of population trends and extinction risks in rare species. Results of the first phase of the project indicate that reproduction is the first component of a plant's life cycle that becomes negatively affected by reduced population size. We will investigate the relationship between population size and reproduction in a large number of declining plant species to determine critical population sizes for reproductive success. The results will be compared with results from the general demographic studies. The second aim of the project is to assess the importance of genetic variability for the population dynamics of declining species. Two different approaches will be used. First, we will study the effect of increased gene flow on the growth and survival of plants in small populations. This study has important implications for habitat management. Second, we will experimentally investigate the importance of initial genetic diversity for the success of founder populations.

Basic analysis of Pimpinella saxifraga

Ökologische und evolutionsbiologische Bedeutung einer persistenten Samenbank für ausdauernde krautige Pflanzen

Pflanzen haben als Reaktion auf die Unvorhersagbarkeit ihrer Umwelt zwei Mechanismen der Risikominderung entwickelt: Ausbreitung und Dormanz. Theoretische Modelle deuten auf eine Reihe spezifischer Bedeutungen dormanter Samen einer Boden-Samenbank für Populationsbiologie, -genetik und Evolutionsbiologie. So könnten Samenbanken durch die Speicherung von Genotypen die genetische Diversität von Populationen erhalten und die genetische Differenzierung dämpfen. Es gibt jedoch nur wenige empirische Studien zum Zusammenhang zwischen genetischer Struktur von Samenbank und oberirdischer Population. Das vorliegende Forschungsprojekt gründet sich auf vorangegangene eigene Studien und wird sich mit Viola elatior, einer ausdauernden Art mit Vorkommen entlang eines Gradienten von Auenwiesen bis Auenwäldern beschäftigen. Ziel des Projekts ist die Hypothesen zu testen, dass (1) eine Samenbank als Reservoir von Genotypen dient, die in der oberirdischen Population verschwunden sind, (2) Variation in Dormanz und Keimung von der genetischen Diversität der Mutterpflanzen abhängen und (3) sich natürlich und erzwungen keimende Samen in ihrer Fitness unterscheiden. Es soll ein Genomscan durchgeführt werden, um potentiell adaptive Loci in Samenbank und oberirdischer Population sowie entlang eines Umweltgradienten zu identifizieren.

Molekulare Diagnostik und Epidemiologie von agronomisch relevanten Schadorganismen

Korrekte Identifikation von landwirtschaftlich relevanten Schädlingen und Krankheiten ist eine wesentliche Grundlage als Entscheidungsgrundlage für Quarantänemaßnahmen und für einen erfolgreichen und nachhaltigen Pflanzenschutz. Zusammen mit epidemiologischen Daten über Häufigkeit, Verteilung und Vorkommen von Arten und über agronomisch relevante Eigenschaften bilden diese Informationen die Basis für die Entwicklung robuster und zuverlässiger Pflanzenschutz-Strategien. 1. Molekulare Diagnostik: Quarantäne-Diagnostik wird im Rahmen der Pflanzenschutzverordung durchgeführt. Sie ist in der Regel dringend und bedarf oft der Entwicklung/Modifikation molekularer Methoden zur genetischen Identifikation von unbekannten Quarantäneorganismen, weshalb dieser Arbeit eine hohe Priorität eingeräumt werden muss. Die Entwicklung von molekularen Markern für spezifische Eigenschaften wie Pathogen- oder Pestizidresistenzen ist die Voraussetzung für epidemiologische Untersuchungen über deren Häufigkeit und Auftreten, für die Pflanzengenotypisierung zur Validierung des Nuklearstocks und für die markerunterstützte Selektion von Apfelsorten. 2. Molekulare Ökologie und Epidemiologie: Vergleichende genomische, populationsgenomische und transkriptomische Analysen von agronomisch relevanten Organismen dienen dazu, Fragen über die genetischen Grundlagen von spezifischen Anpassungen zu beantworten und eröffnen damit neue Möglichkeiten für den Pflanzenschutz. Informationen über populationsgenetische Parameter bilden die Basis zum Verständnis von Faktoren, die für die Verbreitung und Populationsgrößen verantwortlich sind. Epidemiologische Untersuchungen der Häufigkeit und Ausbreitung von agronomisch relevanten Eigenschaften (z.B. Resistenzen) bilden die Grundlage für die Formulierung von Pflanzenschutz-Strategien, die zum Beispiel neu auftretende Pestizidresistenzen bei Insekten berücksichtigen müssen. Die Analyse der Daten bedient sich einer Bioinformatik-Infrastruktur die ständig weiter entwickelt werden muss. Im Rahmen von zwei EU-FP7 Projekten werden genetische Barcodes für die Identifikation von Nematoden (QBOL) etabliert und praxistaugliche molekulare Diagnostik-Tests für NPPO's (Q-Detect) entwickelt.

GenLink - Genetic diversity of Bromus hordeaceus

<p>Original data comes from a project which takes or took place as part of the DFG priority program "Exploratories for large-scale and long-term functional biodiversity research". The data is stored together with descriptive metadata, in combination called a dataset, in the project repository (https://www.bexis.uni-jena.de). Species information was extracted from that original dataset. The second paragraph is part of the metadata of the original dataset.</p> <p>Genetic diversity of Bromus hordeaceus on EPs detected with AFLP</p>

GenLink - Genetic diversity of Cerastium holosteoides

<p>Original data comes from a project which takes or took place as part of the DFG priority program "Exploratories for large-scale and long-term functional biodiversity research". The data is stored together with descriptive metadata, in combination called a dataset, in the project repository (https://www.bexis.uni-jena.de). Species information was extracted from that original dataset. The second paragraph is part of the metadata of the original dataset.</p> <p>Genetic diversity of Cerastium holosteoides on EPs (and three Gridplots in Schorfheide) detected with AFLP</p>

GenLink - Genetic diversity of Veronica chamaedrys

<p>Original data comes from a project which takes or took place as part of the DFG priority program "Exploratories for large-scale and long-term functional biodiversity research". The data is stored together with descriptive metadata, in combination called a dataset, in the project repository (https://www.bexis.uni-jena.de). Species information was extracted from that original dataset. The second paragraph is part of the metadata of the original dataset.</p> <p>Genetic diversity of Veronica chamaedrys on EPs detected with AFLP</p>

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