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Evidence for cell turnover as the mechanism responsible for the transport of embryos towards the vagina in viviparous onychophorans (velvet worms)
(2019-06-07)
Background
Onychophorans, commonly known as velvet worms, display a remarkable diversity of reproductive strategies including oviparity, and placentotrophic, lecithotrophic, matrotrophic or combined lecithotrophic/matrotrophic viviparity. In the placentotrophic species, the embryos of consecutive developmental stages are attached to the uterus via a placental stalk, suggesting they might be transported passively towards the vagina due to proximal growth and distal degeneration of tissue. However, this assumption has ...
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Aphyllophoroid fungi in insular woodlands of eastern Ukraine
(2017-12-22)
Background
Fungi play crucial roles in ecosystems and are among the species-richest organism groups on Earth. However, knowledge on their occurrence lags behind the data for animals and plants. Recent analyses of fungal occurrence data from Western, Central and Northern Europe provided important insights into response of fungi to global warming. The consequences of the global changes for biodiversity on a larger geographical scale are not yet understood. Landscapes of Eastern Europe and particularly of eastern ...
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Expression of NK cluster genes in the onychophoran Euperipatoides rowelli: implications for the evolution of NK family genes in nephrozoans
(2018-07-18)
Background:
Understanding the evolution and development of morphological traits of the last common bilaterian ancestor is a major goal of the evo-devo discipline. The reconstruction of this “urbilaterian” is mainly based on comparative studies of common molecular patterning mechanisms in recent model organisms. The NK homeobox genes are key players in many of these molecular pathways, including processes regulating mesoderm, heart and neural development. Shared features seen in the expression patterns of NK genes ...
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The ‘forma specialis’ issue in Fusarium: A case study in Fusarium solani f. sp. pisi
(2018-01-19)
The Fusarium solani species complex (FSSC) has been studied intensively but its association with legumes, particularly under European agro-climatic conditions, is still poorly understood. In the present study, we investigated phylogenetic relationships and aggressiveness of 79 isolates of the FSSC collected from pea, subterranean clover, white clover and winter vetch grown under diverse agro-climatic and soil conditions within Temperate and Mediterranean Europe. The isolates were characterized by sequencing tef1 and ...
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Roots of symptom-free leguminous cover crop and living mulch species harbor diverse Fusarium communities that show highly variable aggressiveness on pea (Pisum sativum)
(2018-02-14)
Leguminous cover crop and living mulch species show not only great potential for providing multiple beneficial services to agro-ecosystems, but may also present pathological risks for other crops in rotations through shared pathogens, especially those of the genus Fusarium. Disease severity on roots of subterranean clover, white clover, winter and summer vetch grown as cover crop and living mulch species across five European sites as well as the frequency, distribution and aggressiveness to pea of Fusarium spp. ...
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Heterogeneous Winter Wheat Populations Differ in Yield Stability Depending on their Genetic Background and Management System
(2019-11-05)
Twelve winter wheat composite cross populations (CCPs), based on three genetic backgrounds and maintained at the University of Kassel, Germany, under both organic and conventional management, were assessed for yield performance and stability in comparison to two commercial varieties over eight and 10 experimental years. A number of stability parameters were chosen in order to identify populations with either adaptation to specific environments or broad adaptation across environments. The genetic effects of the CCP ...
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Integrated bioenergy and food production
(2015)
Rising global energy needs and limited fossil fuel reserves have led to increased use of renewable energies. In Germany, this has entailed massive exploitation of agricultural biomass for biogas generation, associated with unsustainable farming practices. Organic agriculture not only reduces negative environmental impacts, organic farmers were also prime movers in anaerobic digestion (AD) in Germany. This study’s aim was to identify the structure, development, and characteristics of biogas production associated with ...
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Loss of wobble uridine modification in tRNA anticodons interferes with TOR pathway signaling
(2014)
Previous work in yeast has suggested that modification of tRNAs, in particular uridine bases in the anticodon wobble position (U34), is linked to TOR (target of rapamycin) signaling. Hence, U34 modification mutants were found to be hypersensitive to TOR inhibition by rapamycin. To study whether this involves inappropriate TOR signaling, we examined interaction between mutations in TOR pathway genes (tip41Δ, sap190Δ, ppm1Δ, rrd1Δ) and U34 modification defects (elp3Δ, kti12Δ, urm1Δ, ncs2Δ) and found the rapamycin ...
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Effects of ten years organic and conventional farming on early seedling traits of evolving winter wheat composite cross populations
(2019-06-21)
Early vigour traits of wheat composite cross populations (CCPs) based on high yielding (Y) or high quality (Q) or Y*Q varietal intercross evolving under organic or conventional conditions in parallel populations were studied hydroponically. To eliminate storage and year effects, frozen F6, F10, F11 and F15 seeds were multiplied in one field, resulting in the respective Fx.1 generations. This eliminated generation and growing system effects on seed size for the F6.1 F10.1 and F15.1. Due to a severe winter kill affecting ...
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Normative and cognitive influences on female entrepreneurial reluctance at the base of the pyramid - an explorative study of cleaning ladies in Istanbul
(COMSATS, Inst. of Information Technology, 2013)
Previous research has considered entrepreneurship as a way out of poverty and as a chance to foster economic growth. Moreover, specifically start-ups headed by women have played an important role in the economic development and it has been argued that gender-related issues, amongst others, play a significant role for the performance of a country or region. Against this background, this qualitative study explores desires, reluctances and constraints toward entrepreneurial activities of a comparably homogenous group ...