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Untersuchungen ueber die einheimische Wild- und Haustierpopulationen (ausser Gefluegel) der Tropen einschliesslich Wildtierbewirtschaftung in Afrika

Haltung, Zuechtung, Biologie und Pathologie der Fortpflanzung, Zytogenetik, Jungtierkrankheiten, Zoonosen. Besonders beruecksichtigte Tierarten: Wasserbueffel, autochthone Rinder, Ziegen, Schafe und Schweine sowie Dromedare und Elefanten.

Genetik der evolutionären Reduktion von vier auf zwei Mikrosporangien bei Microseris

Die evolutionäre Reduktion der Mikrosporangienzahl von vier auf zwei in den Antheren von drei Arten der Gattung Microseris läßt sich bei Artkreuzungen genetisch analysieren. In einer Kreuzung haben wir ein Hauptgen und vier modifizierende Gene als Quantitative Trait Loci kartiert. Um die Evolution des Systems weiter verfolgen zu können, müssen die Gene selbst oder sehr eng gekoppelt molekulare Marker gefunden werden. In einer entsprechenden rekombinanten Inzuchtlinie soll das Hauptgen feinkartiert werden und ein Restriktionsfragment mit dem Hauptgen soll kloniert werden.

Emmy Noether-Nachwuchsgruppen, Mechanisms regulating the boron nutritional status in rapeseed and Arabidopsis and their implications for the development of boron-efficient genotypes

Boron (B) is an essential microelement for plants. Despite the use of modern fertilization methods, B deficiency still causes losses in agricultural plant production. Even though many positive effects of B on plant growth and physiology have been reported, a large majority of B functions and the regulatory mechanisms controlling the B nutritional status remain unknown. The main objective of this project is to elucidate how the greatly B deficiency-sensitive Brassica crop plants process and regulate their B status during vegetative and reproductive growth. In this context, the project aims at identifying the mode of action of B in mechanisms regulating the B status itself and uncovering those mechanisms contributing to B efficiency in different genotypes. Plant species subjected to investigation will be the agronomically important oilseed and vegetable plant Brassica napus (rapeseed) and its close relative the genetic and molecular model plant Arabidopsis thaliana. Questions addressed within the scope of this project should lead to a detailed understanding of mechanisms controlling B uptake and allocation from the level of the whole plant down to the cellular level. B transport routes and rates will be determined in sink- and source tissues and in developmental periods with a particularly high B demand. A special focus will be on the identification of B transport bottlenecks and the analysis of B deficiency-sensitive transport processes to and within the highly B-demanding reproductive organs. Recent studies in Arabidopsis suggest that Nodulin26-like Intrinsic Proteins (NIPs), which belong to the aquaporin channel protein family, are essential for plant B uptake and distribution. The systematic focus on the molecular and physiological characterization of B. napus NIPs will clarify their role in B transport and will identify novel NIP-associated mechanisms playing key roles in the B response network.To further resolve the mostly unknown impact of the B nutritional status on gene regulation and metabolism, a transcript and metabolite profile of B-sufficient and B-deficient rapeseed plants will be generated. Additionally, an Arabidopsis transcription factor knockout collection (greater 300 lines) will be screened for abnormalities in responses to the B nutritional status. This will identify yet unknown B-responsive genes (transcription factors and their targets) and gene products (enzymes or metabolite variations) playing key roles in signalling pathways and mechanisms regulating the B homeostasis. Boron (in form of boric acid) and arsenite (As) share in all likelihood the same NIP-mediated transport pathways. To assess the consequences of this dual transport pathway the so far unstudied impact of the plants B nutritional status on the accumulation and distribution of As will be investigated in B. napus. Moreover, the current dimension of the As contamination of Brassica-based food products, to which consumers are exposed to, will be analyzed. usw.

Calcium cycling in the soil-fig-bat compartment of a neotropical rain forest on spatially heterogeneous substrate

Calcium supply in tropical soils is variable and frequently low. In spite of the heterogeneous Ca supply, some plant species, such as figs, maintain high Ca concentrations in their tissues. Figs are keystone species with more than proportional importance for the functioning of a tropical rain forest. High Ca concentrations in fig fruits may render them particularly attractive for frugivorous vertebrates. We propose to study the whole Ca cycling from soil through a selected fig species, Ficus insipida Willd. and frugivorous bats, their main dispersers, back to soil. The study will be conducted in Panama on sites differing in soil Ca status to assess the importance of soil Ca availability for fig fruit content and bat reproduction. We will quantify aboveground Ca fluxes for 16 trees along a gradient of Ca availability in soil. We will determine (1) Ca concentrations in soils, figs and leaves, (2) nutritional quality of fig and other bat-dispersed fruits and their importance for Ca balance in relation to reproduction of fruit-eating bats, (3) Ca fluxes with litterfall, throughfall, stemflow, bat pellets and faeces, (4) the importance of the contribution of bats to the Ca cycle of individual fig trees, and (5) the effect of fig trees on soil Ca concentrations.

IANB-Monitoring BL: IANB = Inventar der Amphibienlaichgebiete von nationaler Bedeutung, BL = Kanton Basel-Landschaft

Überwachung der Bestandesgrösse ausgewählter Amphibienarten durch Fangwiederfang. Nachweis aller anderen Amphibienarten auf dem Niveau Präsenzabsenz. Die überwachten Objekte sind Amphibienlaichgebiete von nationaler Bedeutung.

Naturally occurring protoplasts in two Ulva spp. - Disc sizes from discs grown from protoplasts, after 35 days of germination, under culture conditions

Degradation in Ulva lacinulata and reproduction in Ulva compressa were observed and described for four weeks. The natural occurrence of protoplasts in both species was found. Protoplast yields were calculated each week for several weeks. At the beginning of the experiment, heterogeneity of the thallus was visible under the microscope. The diameter of the cells in the thalli that later became protoplasts were measured. A germination experiment was performed after protoplasts were collected. Germination rates were calculated based on the number of individuals visible by the naked eye at the end of the experiment. 2 % (U. lacinulata) and 4 % (U. compressa) of protoplasts germinated into two morphologies: unattached germlings and unattached discs. Because discs released gametes early in their development, their diameter was measured to estimate the gametes yields produced at the end of the experiment. During degradation of U. lacinulata, we found an increase in biomass after the first two weeks of the experiment. Fresh weight measurements were taken each week and relative growth rates were calculated. Our results provide the first evidence of the natural production of protoplasts in Ulva spp. and estimate that higher seeding yields can be obtained by natural protoplast production than direct gametogenesis.

Fresh weight of Ulva lacinulata's biomass during the degradation experiment

This dataset presents the fresh weight of U. lacinulata's biomass during the degradation experiment. This allowed the calculation of relative growth rates (RGR).

Diameter of the larger green cells found in the thalli of Ulva lacinulata and Ulva compressa that became protoplasts after being released to the water

This dataset presents the diameter of the larger green cells found in the thalli of Ulva lacinulata and Ulva compressa that became protoplasts after being released to the water.

Number of germinated individuals that originated from protoplasts from Ulva lacinulata and Ulva compressa

This dataset presents the number of germinated individuals that originated from protoplasts from Ulva lacinulata and Ulva compressa. The individuals are separated into different morphologies (unattached discs and unattached germlings). Unattached discs are also separated into the color they presented at the end of the experiment to indicate fertility. Green discs: not fertile; Brown discs: fertile; White discs: dead discs after gamete release. This allowed to calculate the germination rate, morphology ratios and percentage of fertility.

Number of protoplasts collected during the degradation experiment with Ulva lacinulata and Ulva compressa

This dataset presents the number of protoplasts collected during the degradation experiment with Ulva lacinulata and Ulva compressa. This allowed the calculation of protoplast yields.

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