Population structure of Phytophthora infestans in Turkey reveals expansion and spread of dominant clonal lineages and virulence     

Mehmet E. Göre  Nedim Altın  Kevin Myers  David E. L. Cooke  William E. Fry  Göksel Özer 《Plant pathology》2021,70(4):898-911

Late blight, caused by the oomycete Phytophthora infestans, is considered the most important and destructive disease of potato in Turkey. In this study, characterization of 367 isolates of P. infestans obtained from the potato-growing areas of the country was carried out to evaluate the pathogen population structure over the 2017–2019 production seasons. The isolates were characterized by numerous features including mating type, in vitro mefenoxam sensitivity, simple-sequence repeat (SSR) markers, and virulence against a set of potato differential lines. Most isolates were A2 mating type (353 isolates). Also, 68% of isolates were resistant to mefenoxam; the remainder were intermediate in their sensitivity and there were no sensitive isolates. SSR-based genotypic analysis of P. infestans populations showed a low genetic diversity. The 13_A2 clonal lineage predominated with a frequency of 92.1%, followed by 34_A1 (3.3%) and 37_A2 (2.7%). Genotypes 34_A1 and 37_A2 were detected only in 2019. This is the first report of 34_A1 and 37_A2 clonal lineages causing late blight disease of potato in Turkey. The most abundant virulence type was one overcoming resistance genes R1, R2, R3, R4, R6, R7, R10, and R11. These results emphasized that the migration of individuals and the asexual generation of subclonal differences were the main factors driving the population structure of P. infestans in Turkey.  相似文献   

Comparative study of the Nicotiana species with respect to water deficit tolerance during early growth     

Toshiyuki Komori  Patricia N. Myers  Shigehiro Yamada  Tomoaki Kubo  Hidemasa Imaseki 《Euphytica》2000,116(2):121-130

Sixty Nicotiana species were examined for tolerance against various osmotica for seed germination and seedling growth in vitro. The species showed a wide variety of tolerance, and based on the results of the in vitro tests, 31 species were selected and further evaluated for salt and drought tolerance in a glasshouse. The degrees of tolerance of germination among the 57 species toward NaCl were approximately related to those toward mannitol, indicating that the osmolarity plays a majorrole in seed germination. However, the responses during the seedling growth differed in NaCl and mannitol or drought, and there was no correlation between salt and drought tolerance. Based on the responses in vitro and in the glasshouse, N. paniculata and N. excelsior were selected as the salt tolerant species, and N. arentsii as the salt sensitive species. The degrees of accumulation of dry matter and of Na⁺ in the leaves were different in the two tolerant species; during NaCl treatment, N. paniculata and N. arentsii accumulated less dry matter relative to the control plants than N. excelsior, and N. paniculata accumulated more Na⁺ in its leaves than N. excelsior and N. arentsii. It is assumed that the two salt tolerant species have different mechanisms for tolerance to the salt. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

GM1 gangliosidosis in Portuguese water dogs: pathologic and biochemical findings     

G K Saunders  P A Wood  R K Myers  L G Shell  R Carithers 《Veterinary pathology》1988,25(4):265-269

Three Portuguese water dog siblings, all females aged 5 to 7 months, were killed following a brief period of neurologic disease. Tissues were processed for light and electron microscopy and for biochemical analyses. All pups had membranous cytoplasmic inclusions in neurons throughout the brain and spinal cord. Cytoplasmic vacuoles were present in cells of many organs outside the nervous system. GM1 ganglioside in brain was markedly elevated in all three dogs, and beta-galactosidase activity was less than 10% of control values. These findings are similar to those in GM1 gangliosidosis of man and animals although the number of organs and tissues containing vacuolated cells is greater.  相似文献   

A re-appraisal of forestry development in developing countries: James J. Douglas. Martinus Nijhoff/Dr. W. Junk Publishers,The Hague, 1983. 178 pp., US$33.00, ISBN 90-247-2830-4     

Norman Myers 《Forest Ecology and Management》1985,12(2):144-146

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Reference values of the brainstem auditory evoked response of methoxyflurane anesthetized and unanesthetized dogs     

L J Myers  R W Redding  S Wilson 《Veterinary research communications》1985,9(4):289-294

The brainstem auditory evoked response (BAER) was recorded from 7 unanesthetized and 27 methoxyflurane anesthetized dogs. A 0.1 msec, 70 dB stimulus delivered at 10 Hz evoked the expected seven wave BAER. Mean peak wave latencies and standard deviations were calculated. Differences were not found between neither right and left ears, nor male and female dogs. The anesthetized dogs had a significantly longer latency for all waves, except wave I, than the unanesthetized dogs. Use of the BAER as a diagnostic technique for brainstem lesions is recommended.  相似文献   

A general method for saturation mutagenesis of cloned DNA fragments   总被引：53，自引：0，他引：53  

R M Myers  L S Lerman  T Maniatis 《Science (New York, N.Y.)》1985,229(4710):242-247

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Experimental peste des petits ruminants (goat plague) in goats and sheep.          下载免费PDF全文

A Bundza  A Afshar  T W Dukes  D J Myers  G C Dulac    S A Becker 《Canadian journal of veterinary research》1988,52(1):46-52

In order to study the pathomorphology and immunohistochemistry of peste des petits ruminants, four goats and two sheep were inoculated intranasally with the Malig-Yemen strain of peste des petits ruminants virus. The animals developed fever, nasal discharge, oral erosions, cough and diarrhea. One goat and one sheep died and one moribund goat was killed. Three animals survived the infection. At necropsy, erosive stomatitis, pneumonia and gastroenteritis were found. Histopathologically the pneumonocytes and epithelial cells of the ileum had eosinophilic cytoplasmic and nuclear inclusions. By an indirect immunoperoxidase method, the nuclei and cytoplasm of the ileal epithelial cells of one goat contained positively (brown) stained antigen, which corresponded to viral nucleocapsids by electron microscopy. Virus appeared to be released through the microvilli of the epithelial cells. We also confirmed the formation of giant cells due to peste des petits ruminants virus.  相似文献   

A survey of diseases among 100 free-ranging baboons (Papio ursinus) from the Kruger National Park     

E E McConnell  P A Basson  V de Vos  B J Myers  R E Kuntz 《The Onderstepoort journal of veterinary research》1974,41(3):97-167

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Sheep pox: experimental studies with a west african isolate   总被引：2，自引：0，他引：2       下载免费PDF全文

Afshar A  Bundza A  Myers DJ  Dulac GC  Thomas FC 《The Canadian veterinary journal. La revue veterinaire canadienne》1986,27(8):301-306

Under conditions of a maximum security laboratory, four cross-bred sheep were inoculated intradermally only or intradermally and intratracheally with a West African isolate of sheep pox virus. All sheep had increased temperature and depression by the fourth or fifth day after infection. Nasal and lacrimal discharge and coughing occurred in all sheep but were more severe in sheep receiving the virus via the tracheal route. From the fifth day after infection, numerous papular erythematous skin lesions developed at the inoculation sites. These were 3-7 mm in diameter and gradually became nodular. Some of these lesions healed and others coalesced to form tumorlike masses. In one sheep, euthanized 14 days after intradermal and intratracheal inoculation, nodular lesions were found in the skin around the eyes, nostrils, oral and perianal regions, the mucosa of the rumen and throughout the lungs. Histologically, skin nodules were characterized by ischemic necrosis, vasculitis, microvesicualtion, eosinophilic cytoplasmic inclusions in the dermal epithelial cells and vacuolar nuclear degeneration. The pulmonary lesion was that of proliferative alveolitis with occasional cytoplasmic inclusions in the alveolar cells and macrophages. Ultrastructurally, large cuboidal virus particles were found both in the skin lesion and inoculated tissue cultures. The sheep pox virus structure was easily distinguished from contagious ecthyma virus, a parapoxvirus which causes sporadic disease in Canada. Serum neutralizing antibodies developed in all the sheep by 14 days postinfection.

The clinical and pathological characteristics of experimental sheep pox produced with this West African isolate were similar to those caused by Neethling virus of lumpy skin disease in cattle.

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Comparison of the performance of the IDEXX SediVue Dx® with manual microscopy for the detection of cells and 2 crystal types in canine and feline urine     

Annalisa M. Hernandez  Graham E. A. Bilbrough  Dennis B. DeNicola  Celine Myrick  Suzanne Edwards  Jeremy M. Hammond  Alex N. Myers  Johanna C. Heseltine  Karen Russell  Marco Giraldi  Mary B. Nabity 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2019,33(1):167-177

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