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21.
In southwestern New Jersey during 1986 and 1987, common barn-owls and pigeons were captured on farmsteads and tested for Toxoplasma gondii antibodies by a modified direct agglutination test. In 1986, 3/28 (10.7%) adult and 0/124 nestling owls tested positive at titers of greater than or equal to 1:40. Additionally, 2/34 (5.9%) pigeons tested had T. gondii antibodies at titer of 1:320. In 1987, 9/38 (27.3%) adult and 18/80 (22.5%) nestling owls tested positive at titers of greater than or equal to 1:25; this includes 3/38 (7.9%) adult and 1/80 (1.3%) nestling owls that tested positive at a titer of 1:50.  相似文献   
22.
Neospora-like protozoal infections associated with bovine abortions   总被引:9,自引:0,他引:9  
Eighty bovine fetuses with presumed protozoal infections from a previous 2-year retrospective study were examined by immunohistochemistry using antisera against Neospora caninum. In 66 (83%) of the fetuses, protozoa were found that reacted positively with anti-N. caninum sera. In three (4%) additional fetuses, protozoa identified as Sarcocystis species did not react, and in two fetuses (3%) single protozoal clusters were found only in hematoxylin and eosin-stained slides. A group of 20 fetuses were chosen for further evaluation. They included 14 fetuses from the first group of 80 fetuses plus six additional fetuses that had large numbers of protozoa in the fetal brain. The 20 fetuses were examined immunohistochemically with antisera to N. caninum, Hammondia hammondi, and Toxoplasma gondii. Protozoa from 3/20 fetuses, identified as Sarcocystis species, failed to react with any antisera. In 16/20 fetuses protozoa reacted positively to antisera against N. caninum, and in most cases reacted to H. hammondi, and weakly to one or more of the antisera against T. gondii. Thick-walled protozoal tissue cysts were found in the brain of four of these 16 fetuses by transmission electron microscopy. The cyst wall morphology was comparable to N. caninum. The results suggested that a single protozoal parasite of unknown identity was responsible for most of the bovine abortions. By immunohistochemistry, the unknown protozoon reacted most strongly and consistently to N. caninum antisera, but was antigenically distinct from N. caninum. Ultrastructurally, tissue cysts found in four fetuses most closely resembled Neospora caninum.  相似文献   
23.
24.
Identification of a small core germplasm set representing the available genetic diversity is essential for its proper evaluation and subsequent utilization in rice improvement programmes. For constituting a small diverse mini‐core panel of Indian rice germplasm, a representative set of 6912 accessions drawn based on their geographic origin from the whole rice germplasm collection available in the National Gene Bank was genotyped using 36 microsatellite markers. Automated fragment analysis of amplicons yielded a total of 435 alleles, with an average 12.4 and range of 3–29 alleles per locus. Polymorphism information content (PIC) ranged from 0.08 (RGNMS190) to 0.86 (RM552) with an average of 0.528. Based on genotyping data, a mini‐core consisting of 98 genotypes was identified. Ninety‐four per cent of the alleles present in the core set were present in the mini‐core. The identified small but diverse panel will be useful for further intensive trait‐specific evaluation and utilization in allele mining.  相似文献   
25.
BACKGROUND: The efficacy of seed dressing and soil application formulations from the isolates of Trichoderma viride (IARI P1; MTCC 5369), T. virens (IARI P3; MTCC 5370) and T. harzianum (IARI P4; MTCC 5371) were evaluated individually and in combination in pot and field experiments during the rainy seasons of 2005, 2006 and 2007 for the management of wet root rot (Rhizoctonia solani) and improvement in the yield of mungbean. RESULTS: A seed dressing formulation, Pusa 5SD, and soil application formulations, Pusa Biogranule 6 (PBG 6) and Pusa Biopellet 16G (PBP 16G), based on Trichoderma virens, were found to be superior to other formulations in reducing disease incidence and increasing seed germination and shoot and root lengths in mungbean. In field experiments, a combination of soil application with PBP 16G (T. virens) and seed treatment with Pusa 5SD (T. virens) + carboxin was superior to any of these formulations individually in increasing seed germination, shoot and root lengths and grain yield and reducing wet root rot incidence in mungbean. Seed treatment was more effective than soil application for all the evaluated parameters. The combined application of Pusa 5SD and carboxin was also superior to individual treatment. CONCLUSION: The efficacy of the evaluated formulations against wet root rot of mungbean proved that the integration of soil application of PBP 16G and seed treatment with Pusa 5SD + carboxin is highly effective for the management of wet root rot, increasing plant growth and grain yield of mungbean Copyright © 2011 Society of Chemical Industry  相似文献   
26.
Four different tree species, Zizyphus mauritiana, Syzygium cumini, Azadirachta indica and Mangifera indica were analyzed for stomatal conductances, sulphate, protein, superoxide dismutase and peroxidase activities for one complete year in an ambient environment with SO2 concentrations ranging between 90 to 10 ug m?3. The low conductances, declined protein content and enhanced sulphate content, superoxide dismutase (SOD) and peroxidase (POD) activities were the general responses exhibited by these species when compared with to the reference site. The pattern of the results indicate that plants under SO2 stress develop an ability to detoxify the phytotoxicity by undergoing certain biochemical changes. Plants which posses high intitial POD activities coupled with greatly enhanced SOD activity (Z. mauritiana) or plants which can enhance both POD and SOD activities (S. cumini) were more tolerant/least affected than that of A. indica and M. indica.  相似文献   
27.
A study was carried out in Madhya Pradesh (Central India) to collect data on injury-causing agricultural incidents during the period 1995-1999. The overall incidence rate was 1.25/1000 workers/year. About 9.2% of the incidents were fatal, and most of the fatal incidents were due to tractors and snakebites (42.9% each). About 77.6% of all incidents were due to farm machinery, 11.8% were due to hand tools, and the remaining 10.6% were due to other sources like snakes, wells, etc. Data on 1,911 incidents reported in 10 leading newspapers published during the five-year period (1995-1999) from different regions of the state were also collected and analyzed, which indicated that only major or roadside agricultural incidents were reported in newspapers. Based on the survey data, it was estimated that in the year 2000 there would have been about 17,480 agricultural incidents in Madhya Pradesh, causing death to about 2,050 workers and injuries to about 16,770 workers, including amputations of limbs, burns, cuts, etc. Total monetary loss due to agricultural injuries in the state of Madhya Pradesh has been estimated as US $27 million/year.  相似文献   
28.
The influence of zinc application on yield, Zn concentration and its uptake by paddy crop (Oryza sativa) was studied in a pot experiment in alluvial soils from Gwalior district. All the soils having less than 3.0 ppm 0.1 N HCl-extractable soil Zn showed significant yield response to application of Zn. The latter also resulted in significant increase in Zn concentration and its uptake by the crop. The plant tissue Zn was found to be significantly correlated at 1 % level with the soil Zn (r=0.82) and Bray's per cent grain yield (r=0.82). Critical level Zn in rice plant taken from top 15 cm of the plant was worked out by statistical procedure of Cate and Nelson and found to be 13.5 ppm below which response to applied Zn is expected.  相似文献   
29.
Cultivars of Triticum aestivum, T. durum, and Secale cereale were grown at low (2 μM) and sufficient (500 μM) phosphorus (P) under ambient carbon dioxide (380 μmol mol?1; aCO2) and elevated CO2 (700 μmol mol?1, eCO2) to study responses of cereal species in terms of growth and P utilization efficiency (PUE) under P x CO2 interaction. Dry matter accumulation increased under eCO2 with sufficient P. Nevertheless, dry matter accumulated at eCO2 with low-P was similar to that obtained at aCO2 with sufficient P. Leaf area was 43% higher under eCO2 with sufficient P. Significant increase in lateral root density, length and surface area were noted at low-P under eCO2. Phosphorus use efficience (PUE) increased by 59% in response to eCO in low-P plants. Thus, eCO2 can partly compensate effect of low-P supply because of improved utilization efficiency. Among cereals, durum wheat was more suitable in terms of PUE under high CO2 and limiting P supply.  相似文献   
30.
Between 1983 and 1989, we examined 1,201 aborted fetuses and dead lambs from the north central United States. Toxoplasmosis was diagnosed in 17.5%, campylobacteriosis in 9.9%, chlamydiosis in 4.7%, and miscellaneous infections in 15.1%. Inflammatory lesions suggestive of infectious causes were seen in 13%. Noninfectious causes were identified in 6.1%, and a diagnosis was not reached in 33.3%. An agglutination test was used to detect Toxoplasma gondii-specific antibodies in ovine fluids. Toxoplasma gondii antibodies were detected in 223 of 1,064 (20.9%) fluids from fetuses and dead lambs. Of 201 seropostive (greater than or equal to 16) fetuses and lambs, T gondii antibody titers (reciprocal) were 16 (21 fetuses and lambs), 32 (10 fetuses and lambs), 64 (2 fetuses and lambs), 128 (7 fetuses and lambs), 256 (9 fetuses and lambs), 512 (5 fetuses and lambs), 1,024 (15 fetuses and lambs), 2,048 (13 fetuses and lambs), 4,096 (13 fetuses and lambs), 8,196 (13 fetuses and lambs), 16,392 (19 fetuses and lambs), and greater than or equal to 32,784 (74 fetuses and lambs).  相似文献   
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