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61.
Y. Luo Z. Ma H. C. Reyes D. Morgan T. J. Michailides 《European journal of plant pathology / European Foundation for Plant Pathology》2007,118(2):145-154
The fungal pathogen Monilinia fructicola causes blossom blight and fruit brown rot of stone fruits in California. In this study, spore densities in the air were monitored
in six orchard/year combinations with Burkard spore traps. A real-time PCR assay was developed to efficiently quantify the
dynamics of spore density in these orchards during the growing season. Different patterns of dynamics of spore density were
observed in these orchards. A linear relationship between numbers of spores counted with a compound microscope and those determined
with the real-time PCR assay was obtained, using the same samples of spore traps. Spore density in five of six orchard/year
combinations ranged from 0.0 to 0.05 spores l−1, except for that in orchard 4, which showed much higher values of spore density in the air, as well as higher values and
wider range of incidences of blossom infection and fruit rot than those in the other orchards. The results demonstrated a
potential method to quantitatively determine spore inoculum potential in orchards by using a real-time PCR assay. 相似文献
62.
ABSTRACT Pollination of the edible fig (Ficus carica cv. Calimyrna) is mediated by a small symbiotic wasp, Blastophaga psenes, that inhabits the syconium cavity of the spring crop of fig pollinator trees (caprifigs). These fig wasps also carry propagules, mainly of Fusarium verticillioides (formerly F. moniliforme) and other Fusarium spp., which cause endosepsis, from pollinator figs to the edible Calimyrna figs in California. Spread of endosepsis was studied in one experimental and up to four commercial Calimyrna fig orchards from 1989 through 1995. The incidence of endosepsis in fruit collected from the tree canopy at either <2.0 m (low) or >2.0 m (high) height, from the north and south of the tree canopy, and from the outer (direct sunlight) and inner (shaded) canopy were similar. More wasps were captured in fig trees located 3.5 to 10 m east or west of the source than in trees 48 to 63 m from the source. In addition, significantly more wasps entered the syconia of trees closest (9 to 12.7 m) to the source than the syconia of the second or third trees (18 to 38.2 m) from the source. Endosepsis decreased with distance from the source, decreasing faster to the south than in other directions from the source. In addition, the disease-vectoring wasps decreased with increased distance from the source, which also described the disease spread from the contamination source for most directions, with a sharper decline south of the source. A 3-year study in three commercial Calimyrna orchards showed there is no secondary spread of fig endosepsis in the field. Although endosepsis can complete as many cycles (three to four) as its vector in fig pollinator trees, in Calimyrna figs it is considered a monocyclic disease. Because fig wasp pollinators prefer to stay close to the contamination source when receptive Calimyrna figs are available in close proximity, only disease sources (caprifigs trees) found among Calimyrna trees or at a distance less than 50 m from the borders of Calimyrna orchards affect endosepsis incidence in commercial orchards. 相似文献
63.
Reichel MP Thornton RN Morgan PL Mills RJ Schares G 《New Zealand veterinary journal》1998,46(3):106-110
CASE: A 13-week-old female boxer pup was found to be suffering from rigidity of the left hindleg. Antibiotic and anti-inflammatory treatment over a 3-week period failed to improve the condition and the pup was humanely killed. METHODS: Serological examination for Neospora antibodies was carried out by the indirect fluorescent antibody test and for Toxoplasma gondii antibodies with a latex agglutination test. A variety of tissues were examined histologically, and the central nervous system by immunohistochemistry and the polymerase chain reaction. RESULTS: The IFAT for anti-Neospora antibodies showed a titre of 1:51 200 in the clinically affected pup while the latex agglutination test for Toxoplasma antibodies was negative. The dam and one of two tested litter-mates had anti-Neospora IFAT titres of 1:1600, the other litter mate was negative. All three were not clinically affected. Histological, immunohistochemical and polymerase chain reaction examinations of the affected pup confirmed the diagnosis of Neospora infection. CONCLUSION: In the live animal, serological examination is thought to be the most useful specific test. Post-mortem examination by traditional histology, immunohistochemistry and the polymerase chain reaction confirmed the diagnosis. The case is discussed in the context of present knowledge about Neospora infection in New Zealand. 相似文献
64.
Enhancement of lymphocyte blastogenesis and neutrophil function by avridine in dexamethasone-treated and nontreated cattle 总被引:3,自引:0,他引:3
The lipoidal amine, N,N-dioctadecyl-N',N'-bis (2-hydroxyethyl) propanediamine (avridine or CP 20,961), formulated in liposomes, was evaluated for its effect on leukocyte kinetics, lymphocyte blastogenesis, and polymorphonuclear leukocyte (PMN) function in dexamethasone-treated and nontreated cattle. In the 1st experiment, cattle were given avridine in a single IM injection of 0.1, 1.0, or 10 mg/kg of body weight. All doses induced swelling at the injection site, a febrile response, and a leukocytosis due to a neutrophilia. Mononuclear cell numbers were normal. All 3 groups of avridine-treated animals had a higher mean lymphocyte blastogenic response to mitogens on the 4 days after administration than did the control nontreated animals. Avridine administration was associated with an enhanced ability of PMN to ingest Staphylococcus aureus and to mediate antibody-dependent cell-mediated cytotoxicity (ADCC). The highest dose (10 mg/kg) was associated with a depression of the ability of PMN to iodinate protein. An effect of avridine on PMN random migration under agarose or nitroblue tetrazolium (NBT) reduction was not observed. In a 2nd experiment, cattle were given no treatment, 0.04 mg of dexamethasone/kg IM, or 10 mg of avridine/kg IM followed 24 hours later by 0.04 mg of dexamethasone/kg. Dexamethasone administration caused a leukocytosis due to a neutrophilia with normal mononuclear cell numbers, an enhancement of PMN random migration under agarose, and an inhibition of NBT reduction, iodination, and ADCC activity of PMN. Dexamethasone did not have a detectable effect on lymphocyte blastogenesis or on ingestion of S aureus by PMN.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
65.
66.
An anonymous, self-administered questionnaire has been used in two independent surveys to try to determine the prevalence of scrapie in the national sheep flock. The disease was recorded in 35 counties in England and Wales. About a third (26.5 and 37.3 percent) of respondents owning 100 or more sheep indicated that they had seen sheep with scrapie in their flocks. The incidences of clinical cases recorded in affected flocks in the two surveys were 0.5 and 1.1 cases/100 ewes/year. At present there is no control over the disposal of these animals. If as has been suggested, an increase in the prevalence of scrapie was a contributory factor in the emergence of bovine spongiform encephalopathy, it would seem logical that measures should be introduced to monitor the prevalence and incidence of scrapie and to control the disposal of clinical cases. 相似文献
67.
Stanley P. Kus DVM MS Joe P. Morgan DVM Vet med dr 《Veterinary radiology & ultrasound》1985,26(6):196-202
Through the use of a purebred dog skull collection, specific positioning recommendations were established for radiography for the three skull types. It is suggested that the central ray of the beam be maintained at the following mean angles relative to the hard palate for the rostrodorsal-to-caudoventral oblique projection of the foramen magnum: dolicocephalic, 30° mesaticephalic, 20° and brachycephalic, 10°. It is recommended that the head be axially rotated as follows to radiographically separate the roots of the superior canine teeth: dolicocephalic, 48° mesaticephalic, 43° and brachycephalic, 35°. If only the cheek teeth require evaluation, the head should be rotated as follows: dolicocephalic, 37° mesaticephalic, 34° and brachycephalic, 25°. For evaluation of the inferior cheek teeth, it is recommended that the head be rotated as follows: dolicocephalic, 46° mesaticephalic, 44° and brachycephalic, 28°. It is recommended that radiographs of the temporo-mandibular joint be made with the skull axially rotated 10° and longitudinally obliqued as follows: dolicocephalic, 10° mesaticephalic, 14° and brachycephalic, 27°. Suggestions for open-mouth projections for evaluation of the tympanic bullae are that the central ray maintain the following angles relative to the hard palate: dolicocephalic, 4° mesaticephalic, 9° and brachycephalic, 21°. It is recommended that a caudoventral-rostrodorsal oblique projection of the nasal cavity made at 30° to the hard palate replace the open-mouth ventrodorsal in brachycephalic breeds. 相似文献
68.
Roth 《European Journal of Forest Research》1867,11(1):428
Ohne Zusammenfassung 相似文献
69.
Roth 《European Journal of Forest Research》1867,11(1):408-413
Ohne Zusammenfassung 相似文献
70.
This experiment evaluated the influence of manure, peat, and vermiculite incorporated at low and high rates (0.0118 and 0.0236 m3/m2) and under two soil moisture regimes on Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) seedling (1+0 for 1+1) xylem water potential (xylem), whole-plant growth, root architectural development, and subsequent field performance under fertilized and non-fertilized conditions. Trends in soil moisture retention were observed (high manure > high peat > control) but there were no differences in xylem. Root length in the wetter soil moisture experiment was initially (three months) greatest for seedlings in high vermiculite and least in high manure but there were no differences among treatments at lifting (eight months). Mean height was greatest for seedlings grown in vermiculite and peat (wetter nursery experiment) after two field seasons. Field fertilization (35 g/seedling) with controlled-release fertilizer in the planting hole stimulated height growth initially, but decreased height and diameter growth during the second growing season. Dramatic improvements associated with the use of nursery soil amendments were not realized, but the failure to identify negative effects, a potential reduction in disease incidence, and improvement of nursery soil physical and chemical properties may justify their use. 相似文献