Ralstonia solanacearum as a potato pathogen in Serbia: Characterization of strains and influence on peroxidase activity in tubers     

Sanja Marković  Slaviša Stanković  Renata Iličić  Sonja Veljović Jovanović  Sonja Milić Komić  Aleksandra Jelušić  Tatjana Popović 《Plant pathology》2021,70(8):1945-1959

Since 2011, the outbreaks of brown rot caused by Ralstonia solanacearum race 3, biovar 2, phylotype IIB-1 (R3/B2/PIIB-1) have significantly compromised potato production in Serbia. During 6 years of monitoring (2013–2018) among 3,524 potato tuber samples, 344 were found positive for brown rot disease. R. solanacearum R3/B2/PIIB-1 was isolated from seven cultivars among 12 monitored, and in five localities among 17 monitored. Cultivar Lady Claire was found to have the highest disease frequency (31.98%). A total of 78 isolates were identified by R. solanacearum-specific primer pairs (PS-1/PS-2 and OLI-1/Y-2), as well as the following tests: restriction fragment length polymorphism analysis, biovar determination, immunofluorescence, biochemical analysis, and pathogenicity. The genetic composition of 36 selected isolates assessed using multilocus sequence analysis with seven genes (adk, gapA, gdhA, gyrB, ppsA, hrpB, and fliC) showed that all isolates originating from Serbian potato were homogeneous. By using the TCS algorithm of concatenated sequences to get insight into the phylogeography of isolates and other R. solanacearum strains deposited in the NCBI database, we showed that their origin is undetermined. Peroxidase (POD) activity was measured in brown rotted potato tubers. A positive correlation was found between POD activity and disease severity rated on the analysed tubers. In general, POD activity increased by 2–22 times in vascular necrotic tissues compared to non-necrotic ones, and depended on disease severity but not on cultivar. Native polyacrylamide gel electrophoresis analysis of POD profiles resulted in a total of 10 distinct POD isoforms, of which PODs 3–5 were highly intensified in response to R. solanacearum.  相似文献   

Antimicrobial and free radical scavenging activities of Teucrium montanum     

Djilas SM  Markov SL  Cvetković DD  Canadanović-Brunet JM  Cetković GS  Tumbas VT 《Fitoterapia》2006,77(5):401-403

The antimicrobial and free radical scavenging activities of petroleum ether, chloroform, ethyl acetate, n-butanol and water extracts of Teucrium montanum were investigated. Ethyl acetate, chloroform and n-butanol extracts expressed a wide range of inhibiting activity against both Gram (+) and Gram (-) bacteria. n-Butanol extract possessed potent DPPH free radical scavenging activity.  相似文献   

Stenotic nasopharyngeal dysgenesis in the dachshund: seven cases (2002-2004)     

Kirberger RM  Steenkamp G  Spotswood TC  Boy SC  Miller DB  van Zyl M 《Journal of the American Animal Hospital Association》2006,42(4):290-297

Medical records of seven dachshunds with congenital nasopharyngeal stenosis from abnormally thickened palatopharyngeal muscles were reviewed. The intrapharyngeal ostium in all cases consisted of only a narrow slit. Dogs were presented with various clinical signs--the most common being dyspnea, expiratory cheek puff, salivation, pharyngeal dysphagia, oral dysphagia (to a lesser extent), and macroglossia. Diagnostic procedures included direct pharyngeal inspection, pharyngeal and thoracic radiography, fluoroscopy, lingual ultrasonography, biopsies in two dogs, and a postmortem examination in one dog. Diagnoses were readily made with radiographs and visual examinations. Macroglossia was confirmed with transcutaneous ultrasonography or a transmandibular finger test.  相似文献   

<Emphasis Type="Italic">Fusarium langsethiae</Emphasis> (Torp and Nirenberg), investigation of alternative infection routes in oats     

Hege?Hvattum?Divon  Jafar?Razzaghian  Heidi?Udnes-Aamot  Sonja?Sletner?KlemsdalEmail author 《European journal of plant pathology / European Foundation for Plant Pathology》2012,132(1):147-161

Fusarium langsethiae is a recently characterized fungus within the genus Fusarium. It is found as a grain contaminant of small grain cereals such as oats and barley, and to a lesser extent wheat. Fusarium langsethiae is particularly widespread in the Nordic countries and the UK where it poses a serious problem as the main producer of T-2 and HT-2 mycotoxins. The biology of F. langsethiae and its interaction with the plant remains poorly understood, partly hampered by difficulties reproducing a natural level of infection under controlled conditions. The reported study was designed as a series of glasshouse experiments to advance our understanding of F. langsethiae biology by investigating alternative infection routes and its proliferation in oats, Avena sativa. Various methods of seed, soil, and seedling inoculation, boot injection and spray inoculation, were tested. The results clearly show a strong preference of F. langsethiae for the panicle, ruling out alternative infection routes. At relatively low temperatures spray infection, accompanied by prolonged humidity, ensured a thorough establishment of the fungus both at flowering and at early dough stage. Boot injection proved to be a reliable working tool for production of an even and predictable grain infection. Apart from in the panicle, considerable fungal proliferation was only detected in flag leaf nodes, and was a direct consequence of the boot injection method. Fungal presence in the node tissue also correlated with significant stunting of infected shoots. In light of the results the pathogenic and endophytic abilities of F. langsethiae are discussed.  相似文献   

Gene Localization of Aspartate Aminotransferase and Endopeptidase Isozymes in Wheat and Rye Using Developmental and Organ-Specific Patterns     

Sonja  Drefahl R. Buschbeck 《Plant Breeding》1991,107(3):218-225

Wheat, rye and wheat-rye addition lines have been investigated regarding their developmental and organ-specific isozyme patterns of aspartate amino-transferase (AAT) and endopeptidase (EP). Evidence is given, that development-specific isozymes of AAT are encoded by chromosomes 3R and 4R of ‘Imperial’ rye which can be used as biochemical markers up to leaf age of 14 days. Organ-specific increase of intensity of bands for AAT in stems could be assigned to genes or alleles of chromosome 3A of ‘Chinese Spring’ wheat. For EP new markers were localized on chromosomes 4R and 6R of ‘Imperial’ rye showing variability. Utilization of these markers is possible at all developmental stages of the leaves. Mechanisms of gene regulation are discussed.  相似文献   

Farmer goals and management styles: Implications for advancing biologically based agriculture     

Sonja Brodt  Karen Klonsky  Laura Tourte 《Agricultural Systems》2006

This paper examines differences in the management styles of a purposive sample of almond and winegrape growers in California’s Central Valley, including participants and non-participants in biologically integrated farming systems programs. Using Q methodology, we elicited rankings of economic and social values and goals as they relate to farm production, environmental stewardship, family and community, and leisure. These rankings led to three distinct management styles, labeled as Environmental Stewards, Production Maximizers, and Networking Entrepreneurs. The results demonstrate that farmers make decisions following diverse management strategies and suggest that outreach programs aimed at advancing biologically based farming practices must address these differences to be most effective.  相似文献   

Entwicklung,Eigenschaften und Klassifikation von Dünenböden der Ostfriesischen Inseln – am Beispiel Spiekeroogs     

Luise Giani  Sonja Buhmann 《植物养料与土壤学杂志》2004,167(5):645-648

Pedogenesis, properties, and classification of dune soils of the East Frisian Islands (southern North Sea coast of Germany)—exemplified by the island Spiekeroog The aim of this study was a detailed pedological investigation and exact classification of dune soils of the East Frisian Islands. The following soil‐forming processes were identified on a laboratory‐data basis: humus accumulation and dislocation, carbonate loss, acidification, modification of exchangeable cations, and base‐saturation decrease. A slight iron oxide accumulation was visible in the field, but not confirmed by laboratory data. Applying the qualitatively and quantitatively defined horizons from the German classification, these soils cannot be classified as Regosols, Braunerden, and Podsols but they fit perfectly in the Arenosols as defined in the WRB.  相似文献   

In-depth mechanistic study on the formation of acrylamide and other vinylogous compounds by the maillard reaction   总被引：2，自引：0，他引：2  

Stadler RH  Robert F  Riediker S  Varga N  Davidek T  Devaud S  Goldmann T  Hau J  Blank I 《Journal of agricultural and food chemistry》2004,52(17):5550-5558

The formation of acrylamide was studied in low-moisture Maillard model systems (180 degrees C, 5 min) based on asparagine, reducing sugars, Maillard intermediates, and sugar degradation products. We show evidence that certain glycoconjugates play a major role in acrylamide formation. The N-glycosyl of asparagine generated about 2.4 mmol/mol acrylamide, compared to 0.1-0.2 mmol/mol obtained with alpha-dicarbonyls and the Amadori compound of asparagine. 3-Hydroxypropanamide, the Strecker alcohol of asparagine, generated only low amounts of acrylamide ( approximately 0.23 mmol/mol), while hydroxyacetone increased the acrylamide yields to more than 4 mmol/mol, indicating that alpha-hydroxy carbonyls are much more efficient than alpha-dicarbonyls in converting asparagine into acrylamide. The experimental results are consistent with the reaction mechanism based on (i) a Strecker type degradation of the Schiff base leading to azomethine ylides, followed by (ii) a beta-elimination reaction of the decarboxylated Amadori compound to afford acrylamide. The beta-position on both sides of the nitrogen atom is crucial. Rearrangement of the azomethine ylide to the decarboxylated Amadori compound is the key step, which is favored if the carbonyl moiety contains a hydroxyl group in beta-position to the nitrogen atom. The beta-elimination step in the amino acid moiety was demonstrated by reacting under low moisture conditions decarboxylated model Amadori compounds obtained by synthesis. The corresponding vinylogous compounds were only generated if a beta-proton was available, for example, styrene from the decarboxylated Amadori compound of phenylalanine. Therefore, it is suggested that this thermal pathway may be common to other amino acids, resulting under certain conditions in their respective vinylogous reaction products.  相似文献   

Reduction processes in forest wetlands: Tracking down heterogeneity of source/sink functions with a combination of methods     

Sonja Paul  Christine Alewell 《Soil biology & biochemistry》2006,38(5):1028-1039

Wetlands are considered to be the biggest unknowns regarding the influence of global climate change on element dynamics, so knowledge of processes and conditions controlling sink and source functions of redox processes is crucial. The aim of this study was to investigate the sink/source function of nitrate, Fe, sulfate reduction and methanogenesis of an upland and a lowland fen within a boreal spruce catchment, southern Germany. We used suction cups and anaerobic dialysis chambers for soil solution sampling, FeS probes for the determination of S oxidation potential and stability of anoxic conditions and analysis of the soil solid phase (contents of C, S and Fe species). Both fens had high rates of nitrate reduction and potentially high rates of CH₄ production. The upper few cm of all profiles were oxic with low CH₄ concentrations, suggesting low CH₄ emission rates from the soil, though emission by vascular plants cannot be excluded. Sulfate and Fe reduction processes differed significantly in the fens. The upland fen was characterized by relatively stable anoxic conditions, low Fe contents but high contents of organic S and low C/S ratios. We concluded that the upland fen is an effective sink for sulfate with long-term S storage. In contrast, the lowland fen was characterized by alternating oxidation-reduction cycles with high Fe contents, lower contents of organic S and higher C/S ratios. Thus, even though low sulfate and high Fe concentrations in soil solutions indicated high reduction rates in the lowland fen, long-term storage of S is not likely in this fen. Differences in biogeochemical processes between sites are most likely not associated with hydrology but rather with the role of vascular plants.  相似文献   

Indirect effects of carbon and nutrient amendments on the soil meso- and microfauna of a beechwood     

Mark Maraun  Jörn Alphei  Philip Beste  Michael Bonkowski  Romuald Buryn  Sonja Migge  Maren Peter  Matthias Schaefer  Stefan Scheu 《Biology and Fertility of Soils》2001,34(4):222-229

  相似文献