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The orchard of the Institute of Fruit Breeding of the German Federal Centre of Breeding Research on Cultivated Plants in Dresden-Pillnitz was highly affected by fire blight in 2003. Infected pomefruit trees were observed over a period of nearly 3 months. The first symptoms on pear trees were found on May 19th. The pathogen Erwinia amylovora was confirmed officially on May 26, and the last infected apple trees were detected the 11th of August. The infected trees had to be grubbed at the decision of the Phytopathological Authority. In total, 1164 apple and 478 pear trees were grubbed, including the entire pear collection of the gene bank. Of 35 wild species of pear, 49 accessions, eight accessions of six species each, showed infections. The apple collection of the gene bank included 33 wild species, with 365 accessions, and 845 cultivars and clones. Ten accessions of nine wild apple species and 81 cultivars/clones of these collections showed fire blight infection. The source of infection was the pear collection, and the distance from that source was important for the occurrence of infection. Field plots close to the pear collection had tree losses of 10–34%, while more distant plots had losses of 0–6%. Around 80% of the lost apple trees were detected and grubbed from 27th May to 11th June. Some of the cultivars bred in Dresden-Pillnitz, e.g. ‘Pilot’ and ‘Rekarda’, were affected by fire blight in most field plots, whereas most others were affected mainly only in plots adjacent to the infection source. A correlation of r=?0.72 could be calculated for rating in artificial shoot inoculations and percentage of trees of resistant cultivars lost. The cultivars ‘Pirol’, ‘Reanda’, ‘Remo’, ‘Rene’, ‘Renora’, ‘Resi’, and ‘Retina’ showed only a very low numbers of infected trees. No tree of ‘Rewena’ showed symptoms of fire blight. Despite a tendency to postblooming, only 8.9% of ‘Pinova’ trees had to be grubbed. 相似文献
3.
Monika Jamioł Jacek Wawrzykowski Marta Kankofer 《Reproduction in domestic animals》2021,56(7):1040-1049
One of the most important processes determining the proper course of gestation and its physiological termination in cows is the adhesion of epithelial cells allowing for direct contact of maternal and foetal parts of the placenta. Throughout pregnancy, placental cells are under strict hormonal control, which among others regulates the concentration and activity of specific proteins participating in the extracellular matrix remodelling of foetal membranes. The aim of the study was to evaluate the influence of progesterone and prostaglandin F2α on the adhesion of epithelial cells at early-mid pregnancy in cows. Additionally, the impact of selected hormones on anti-adhesive properties of decorin was evaluated. Caruncular epithelial cells were isolated from healthy cows during pregnancy, immediately after slaughter. Primary cell cultures derived from the 2nd and 4th month of gestation were used in the experiments. The viability of cells was assessed by MTT assay. The adhesion of cells to fibronectin was measured spectrophotometrically. The activity of metalloproteinases was confirmed by the metalloproteinase assay. Progesterone (10–5 and 10–7 mol/L) and prostaglandin F2α (10–4, 10–5 and 10–7 mol/L) increased the viability of bovine caruncular epithelial cells in the 2nd month of pregnancy. The treatment with prostaglandin F2α significantly reduced the number of adherent cells from the 2nd month of gestation at the doses of 10–4 and 10–5 mol/L. Both progesterone and prostaglandin F2α were shown to have an effect of decorin resulting in both a decrease in metalloproteinase activity and an increase in adhesion of cells to fibronectin. 相似文献
4.
Identification of internal control genes in milk‐derived mammary epithelial cells during lactation cycle of Indian zebu cow 下载免费PDF全文
5.
The influence of crossbreeding on collagen solubility and tenderness of Infraspinatus and Semimembranosus muscles of semi‐intensively reared young bulls 下载免费PDF全文
Monika Modzelewska‐Kapituła Zenon Nogalski Aleksandra Kwiatkowska 《Animal Science Journal》2016,87(10):1312-1321
The aim of the present study was to investigate the effects of crossbreeding on collagen content and solubility, shear force (WBSF) and the eating quality of Infraspinatus (INF) and Semimembranosus (SM) muscles of young bulls and the relationships between collagen content and solubility, shear force and the eating quality of beef. The experimental material comprised muscles of crossbred young bulls (about 600 days old) of Polish Holstein‐Friesian (PHF) × Limousine (LM) (n = 10), PHF × Charolaise (CH) (n = 9), PHF × Hereford (HER) (n = 9) breeds. The crossbreeding influenced WBSF, aroma and taste, total, water‐soluble, acid‐soluble, total soluble and insoluble collagen content, as well as the acid‐soluble, total soluble and insoluble collagen proportions. WBSF was significantly negatively correlated with sensorial tenderness and water‐soluble collagen content. The eating quality of beef obtained from different crossbreds was similar; however, the meat from PHF × LM and PHF × HER bulls had lower WBSF values than PHF × CH bulls. © 2016 Japanese Society of Animal Science 相似文献
6.
Azin Rekowski Monika A. Wimmer Bernd Hitzmann Bernhard Hermannseder Heike Hahn Christian Zrb 《植物养料与土壤学杂志》2020,183(2):260-270
Background: Nitrogen losses is an economic problem for wheat production and a high risk to the environment. Therefore, improved N fertilizer management is a key to increasing the N efficiency and minimizing N losses. To increase N efficiency, enhanced fertilizers such as urea combined with urease inhibitor can be used. Aims: The aim of present study was to evaluate the effects of different N forms on grain storage protein subunits in winter wheat and to examine whether the observed changes correlate with parameters of baking quality. Methods: The investigation was performed over two consecutive years at two locations in Germany. Protein subunits were analyzed by SDS‐PAGE. Results: Protein concentrations were similarly increased after fertilization with ammonium nitrate and urea + urease inhibitor. Analysis of the individual storage protein fractions indicated that both fertilizers specifically enhanced ω‐gliadins and HMW glutenins, but the effect was more pronounced in the ammonium nitrate treatment. Application of urea + urease inhibitor had greater influence on the protein composition and resulted in higher specific baking volume as well as the best fresh keeping ability, in comparison with urea treatment. Conclusion: Considering that the urea + urease inhibitor treatment resulted in almost comparable improvements of NUE and baking quality, with the additional benefit of reduced N losses in combination with easy handling, urea + urease inhibitor can be recommended as a viable alternative to both urea alone and ammonium nitrate treatments. This opens up an opportunity for the reduction of N loss in wheat production when use of urea is preferred. 相似文献
7.
Bodi D Fry H Schafft H Lahrssen-Wiederholt M Preiss-Weigert A 《Journal of agricultural and food chemistry》2012,60(28):6946-6952
Maduramicin is a coccidiostat authorized as feed additive in the European Union for chickens and turkeys for fattening but not for laying hens, considering the risk of residues in eggs. The unavoidable cross-contamination of non-target feed with coccidiostats is regulated by Commission Directive 2009/8/EC and resulting carry-over in food by Commission Regulation (EC) No. 124/2009. To verify the compliance of the maximum levels for maduramicin in feed (50 μg/kg) and eggs (2 μg/kg), the carry-over from feed into eggs was investigated. Diets containing 10, 30, and 50 μg of maduramicin/kg of feed were fed to laying hens. Feed, egg white, and yolk were analyzed by LC-MS/MS. Maduramicin residues were only detected in in egg yolk. Feeding the 10 μg/kg maduramicin diet resulted in maduramicin concentrations up to 2.5 μg/kg in whole eggs, already exceeding the maximum level. A carry-over rate of 8% maduramicin from feed into eggs was calculated. 相似文献
8.
Zusammenfassung Erstmalig wurden mit den vorliegenden Untersuchungen Spargelstangen zur Haupterntezeit auf endophytischen Pilzbefall untersucht. Sie zeigen, dass im Ernteprodukt zwar Fusarium proliferatum als potenzieller Mykotoxinbildner zu finden ist. Eine mögliche natürliche Kontamination mit Fumonisinen bestätigte sich nicht. Von den mit F. proliferatum infizierten Stangen wies nur eine Stange mit grau-rosa-orange farbenen Gewebeveränderungen an der Basis sichtbare Symptome auf. Allgemeine Rückschlüsse auf eine mögliche Gefährdung oder Nichtgefährdung des Verbrauchers beim Verzehr von mit F. proliferatum kontaminierten, symptomlosen Stangen können aus der Analyse nicht gezogen werden. Hierzu müssen weitergehende Untersuchungen zur Wirt-Pathogen-Interaktion erfolgen und die phänotypischen und genotypischen Einflussfaktoren in diesem Prozess noch näher untersucht werden. 相似文献
9.
Beckmann L Müller M Luber P Schrader C Bartelt E Klein G 《Berliner und Münchener tier?rztliche Wochenschrift》2003,116(11-12):487-490
Foodborne infections with Campylobacter spp. are increasing, especially antibiotic resistant strains are emerging. Quinolone resistant isolates can cause failure of therapy in severe clinical infections. Molecular characterisation is needed for the detection of resistant variants of C. jejuni. Therefore 23 isolates from poultry and human medicine as well as three control strains were tested for their minimal inhibitory concentration, their Single-Strand-Conformation-Polymorphism (SSCP)-PCR pattern (a method for the detection of resistance determining point mutations), and their sequence of the quinolone resistance determining region (QRDR). Six different SSCP types could be identified: two types for quinolone resistant isolates and other types containing so called silent mutations without influence on the resistance. A genotypic monitoring of the quinolone resistance in C. jejuni can be useful for the early detection of new resistance variants. As a screening method for detection of point mutations in the QRDR the SSCP-PCR can be applied. Compared to other genotypic methods the SSCP-PCR is less time and cost consuming and needs only standard technical equipment. 相似文献
10.
Jankowski MK Ogilvie GK Lana SE Fettman MJ Hansen RA Powers BE Mitchener KM Lovett SD Richardson KL Parsley L Walton JA 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2002,16(1):105-108
Matrix metalloproteinases (MMPs) are enzymes that play key roles in angiogenesis, tumor invasion, and metastasis in a wide variety of species. The purpose of this study was to evaluate pro and active MMP 2 and 9 concentrations in tumor, normal stromal tissue, and serum from tumor-bearing cats. We hypothesized that serum concentrations of pro and active forms of MMPs 2 and 9 would be predictive of MMP concentrations in tumor tissue and that these MMP concentrations would correlate with the histopathologic grade of the malignancies. Pro and active forms of MMPs 2 and 9 were determined by gelatin zymography and subsequent computerized densitometry from tumor and nearby stromal tissue and serum from 49 cats with various malignancies. The serum concentrations of MMPs from these tumor-bearing cats were compared with serum concentrations of MMPs from 44 normal cats of similar age and gender. Measurable concentrations of MMPs 2 and 9 were found within tumor, stromal, and serum samples. Mean concentrations of total pro and active MMPs 2 and 9 within tumor tissue were significantly higher (P values <.0001, .0031, <.001, and .0064, respectively) when compared with stromal tissue from the same animals. Serum MMP concentrations from tumor-bearing cats were higher than those from normal cats. Poor correlation was found between serum MMP concentrations and tissue MMP concentrations of increasing histologic grades of malignancies. 相似文献