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Kleingärten als Teil „urbaner Landwirtschaft": Rolle des Kleingartenwesens für die Ernährungssicherung in den Städten
No full textOn flower bud differentiation in Chinese chestnut (Castanea mollissima Blume)
Full text linkIn Chinese Chestnut flower bud differentiation is of great importance for nut development and thus yield. The formation of female flowers in relation to male flowers is rather low, and future cultural practices are aimed to increase the number of female flowers. The Chinese Chestnut is andromonoecious and shows dichogamy. From the structure of buds incompletely and completely mixed flower buds are evident. Male and female flower buds can not be differentiated by their external appearance, but only by their internal structure. Catkin primordia, developing into male catkins, have the form of a maize cob. Most of the bisexual catkin primordia form after break of the buds. In some male flowers of bisexual catkins degenated female flowers were evident.Bei der Chinesischen Esskastanie (Castanea mollissima Blume) ist die Blütenknospendifferenzierung von herausragender Bedeutung für die Nuss- und damit Ertragsbildung. C. mollissima Blume ist andromonozisch und auch dichogam. Über die detaillierte Differenzierung der Kastanienblüten und vor allem die kritische Phase der Differenzierung weiblicher Blüten ist nur wenig bekannt. Die Blütendifferenzierung konnte bei den zukünftigen Kulturmaßnahmen voll genutzt werden, um die Bildung der weiblichen Blüten zu fördern, die im Vergleich zu den männlichen Blüten, nur in geringer Anzahl ausgebildet werden. Von der Knospenstruktur her sind unvollständig und vollständig gemischte Blütenknospen nicht klar zu differenzieren, aber die Blütenknospen unterschieden sich deutlich von Blattknospen in ihrer inneren Struktur. Die Blütenkätzchenanlage, die sich später zum männlichen Blütenkätzchen entwickelt, hat kurz vor dem Austreiben der Blütenknospen eine maiskolbenförmige Struktur. Die meisten zweigeschlechtlichen Blütenkätzchenanlagen bildeten sich nach dem Austreiben der Knospen und sehen kurz und kegelförmig aus. In manchen männlichen Blüten des zweigeschlechtlichen Blütenkätzchens waren degenerierte Fruchtblätter deutlich zu erkennen
Quarter-selective dry cow therapy to reduce the antibiotic use in dairy farming
Full text link• One approach to reduce the use of antibiotics is the quarter-selective dry cow therapy, where only quarters infected with major pathogens are treated with antibiotics at dry-off. • The project MinimA investigated this pathogen-based approach on commercial dairy farms, resulting in a substantial reduction in the use of antibiotics at dry-off. • To achieve a sustainable reduction in antibiotic use, the focus must be on preventing new intramammary infections during the dry period
Sinonasal angiofibroma in a horse
Full text linkA 34-year-old Haflinger gelding presented with a unilateral, expansile, intranasal mass that regrew after partial excision. After euthanasia, a large pedunculated mass that originated from the left caudal maxillary sinus and obliterated the left nasal cavity was seen by radiological and macroscopic examination. Histopathology revealed a poorly cellular, expansile, well-vascularized neoplasm composed of a loosely arranged meshwork of spindle cells and collagen fibres. Spindle cells were immunopositive for alpha-smooth muscle actin and occasionally for vimentin, whereas endothelial cells immunolabelled for factor VIII-related antigen. Based on clinical, radiological, macroscopic and microscopic similarities to canine and human cases, the mass was diagnosed as an angiofibroma
The potential of fruit genetic resources in Central Asia and especially Tajikistan for breeding climate-tolerant crops
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Cultivation of fiber nettle (Urtica dioica L.) in an agroforestry system for peat substitution in horticulture
Full text linkThe German Federal Government aims to drastically reduce or even ban the use of peat in growing media in commercial horticulture by 2030. The joined project “Development and evaluation of peat-reduced production systems in horticulture” (ToPGa) explores and evaluates the challenges and effects of the employment of peat substitutes for practical application. For this, a special focus is set on the evaluation of the renewable, locally grown resource fiber nettle (Urtica dioica L.) as a potential peat substituent. In this approach, three fiber nettle genotypes were established in an alley cropping agroforestry system. To evaluate the dependency of the nettle growth on genotype and distance to the tree line, nettle yield was determined over four consecutive years. The differences in yield between different genotypes were not significant in first three years of harvest. In general, genotype L18 showed a higher biomass yield as B13 and Z10. The yield of nettles growing 6 to 12 m from the tree line was significantly higher. We conclude that while all genotypes can tolerate the growing conditions close to the trees, nettle plants gain higher yields when grown further from the tree line with a maximum yield of 11.4 t ha-1 in the fifth year of cultivation. Retted nettle exhibits a low pH and minimal salinity. Nettles accumulate only low amounts of trace elements. Overall, chemical properties vary according to the season of harvest. Annual variations in retted material are not significant
Compensatory mechanisms in γδ T cell-deficient chickens following Salmonella infection
Full text linkAvian γδ T lymphocytes are highly abundant in the intestinal mucosa and play a critical role in immune defense against infectious diseases in chickens. However, their specific contributions to infection control remain poorly understood. To investigate the role of γδ T cells and their possible compensation, we studied wild-type and γδ T cell knockout chickens following infection with Salmonella Enteritidis. Bacterial loads in the liver, cecal content, and cecal wall were quantified. Immune cell populations in blood, spleen, and cecum were analyzed using flow cytometry. Immune gene transcription in sorted γδ (TCR1+) and TCR1- cell subsets as well as cecal tissue was measured by RT-qPCR. Strikingly, chickens lacking γδ T cells had significantly higher bacterial loads in the liver and more extensive Salmonella invasion in the cecal wall during the early stages of infection compared to wild-type birds. In blood, infected γδ T cell knockout chickens displayed a significantly increased percentage of CD25+ NK-like cells. In both blood and tissue, infected wild-type chickens demonstrated an increased absolute number of CD8αα+hi γδ T cells (CD4-). Conversely, γδ T cell knockout chickens exhibited an augmented cell count of a CD8αα+hiCD4-TCR1- cell population after infection, which might include αβ T cells. At 7 days post infection (dpi), gene expression analysis revealed elevated transcription of the activation marker IL-2Rα and proinflammatory cytokines (IL-17A, IFN-γ) in CD8αα+hiCD4-TCR1- cells from γδ T cell knockout chickens compared to CD8αα+hi γδ T cells from wild-type birds. By 12 dpi, these differences diminished as transcription levels increased in γδ T cells of wild-type animals. Our findings demonstrate that γδ T cells play a role in early immune protection against Salmonella Enteritidis infection in chickens. In later stages of the infection, the γδ T cells and their functions appear to be replaced by other cells