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M. B. Chhabra R. M. Bhardwaj O. P. Gautam R. P. Gupta 《Tropical animal health and production》1981,13(1):222-226
Summary Serological investigation by the indirect haemagglutination test forToxoplasma antibodies was carried out in a flock of dairy goats. Antibody titres ranging from 1:4 to 1:1,024 were found in 34% of 371 apparently healthy animals. High antibody titres of 1:256 suggestive of recent infection were noted in 18 (4.9%) animals including 13 nannies. The occurrence of a number of non-brucella abortions associated with high serological titres and the isolation of the parasite from the brain tissues of an aborted foetus suggestedToxoplasma as a probable aetiologic factor. Sera having significant levels of haemagglutinating antibodies (1:128) were also found positive to the card agglutination test. Epidemiological aspects and the public health potential of subclinical toxoplasmosis in dairy goats are discussed.
Infecciones Y Abortos En Cabras Lecheras Debido AToxoplasma
Resumen Se realizaron investigaciones serológicas de toxoplasmosis mediante la prueba indirecta de hemaglutinación en un rebaño de cabras lecheras. Se encontraron títulos de 1:4 a 1:1024 en 34% de 371 animales aparentemente sanos. Títulos de 1:256 sugestivos de infecciones recientes, se encontraron en 18 (4.9%) animales, incluyendo 13 hembras paridas. La ocurrencia de un significativo número de abortos no asociados con brucela, títulos serológicos altos de toxoplasmosis y el aislamiento del parásito del cerebro de fetos abortados, sugiere que eltoxoplasma es el factor etiológico más importante. Se discuten aspectos epidemiológicos de importantcia para la salud pública, relacionados con el potencial de la toxoplasmosis (subclínica) en cabras lecheras.
Toxoplasmose Et Avortement Chez Les Chevres Latiteres
Résumé Des investigations sérologiques par la méthode de l'agglutination indirecte pour rechercher des anticorps toxoplasmiques ont été faites sur un troupeau de chèvres laitières. Des anticorps ont été mis en évidence chez 34 p.100 des 371 animaux apparemment sains à des titres allant de 1:4 à 1:1024. Des titres élevés d'anticorps atteignant 1:256 ont été relevés chez 18 (soit 4,9 p.100) des animaux comprenant 13 chèvres, ce qui fait penser à une infection récente.L'existence de nombre d'avortements non-brucelliques associés avec des titres sérologiques élevés et l'isolement du parasite des tittus cérébraux d'un foetus avorté suggerent que les Toxoplasmes en ont probablement été le facteur étiologique. Des sérums ayant des taux significativement élevés d'anticorps agglutinants (1:128) ont également été reconnus comme positifs par le test d'agglutination en EAT. Les aspects épidémiologiques et le danger potentiel pour l'homme de ces cas subcliniques de toxoplasmose chez les chèvres laitières sont discutés.相似文献
3.
S. C. Gupta 《Plant Breeding》1994,112(2):135-140
Screening of a population of Ocimum basilicum var. glabratum Benth., raised from seeds collected from France, West Africa and Kerala (India) was carried out for chemical composition of its essential oils. In all three collections, plants were found to be comprised of 3 chemotypes which were morphologically indistinguishable, but each chemotype was found to be capable of intercrossing freely with the other two. Selfing was carried out during 4 consecutive generations, after which three pure lines were established. Study of the selfed progeny of each collection exhibited an interesting segregation in S2 and S3 generations. Along with segregation in F2 and F3 generations of various hybrids the results can be explained by assuming a gene ‘M’ existing in 3 (or more) allelic forms: The allele M0 for biosynthesis of estragole (methyl chavicol) is dominant to allelcs M1 , for eugenol and M2 for camphor. Also, allele M1 is dominant to allele M2 . The assumption was further confirmed by testcrosses of F1 hybrids of each cross with their recessive parent. 相似文献
4.
Naresh K. Bainsla Rahul M. Phuke Xinyao He Vikas Gupta Santosh K. Bishnoi Rajiv K. Sharma Najibeh Ataei Susanne Dreisigacker Philomin Juliana Pawan K. Singh 《Plant pathology》2020,69(6):1161-1171
Spot blotch (SB), caused by Bipolaris sorokiniana, is a devastating disease of wheat globally, especially in South Asia and South America. Understanding the genetics of resistance to SB is important for developing breeding strategies to improve resistance. A panel of 301 genotypes from Afghanistan was phenotyped over two crop seasons using a mixture of virulent B. sorokiniana isolates and genotyped using DArTSeq to obtain genome-wide markers. Fifty genotypes (16.6%) showed disease scores less than the resistant control. Principal component analysis using the genotypic data clustered the genotypes into five different groups. Among models used for genome-wide association mapping, the multilocus mixed model, and fixed and random model circulating probability unification algorithms were most effective in identifying significant marker-trait associations (MTA). Twenty-five MTAs at p ≤ .001 were identified on chromosomes 1A, 1B, 1D, 2B, 2D, 3A, 3B, 4A, 5A, 5B, 6A, 7A, and 7D, indicating the quantitative nature of resistance to SB. Phenotypic variation explained by these markers ranged from 2.0% to 17.7%, and genomic regions on the chromosomes 1D, 2D, 3A, 3B, 4A, 5A, and 5B coincided with loci identified in previous studies. Three single nucleotide polymorphism (SNP) markers on chromosomes 1B (SNP 1113207) and 5A (SNPs 5411867 and 998276) were significant in both crop seasons as well as in the combined analysis across seasons. Marker 5411867 is close to Vrn-A1, shown to be associated with SB in previous studies. Furthermore, among known SB resistance genes, Sb2 on chromosome 5B was predicted to be significant in this panel. 相似文献
5.
S.K. Jalota K.B. Singh R.K. Gupta Anil Sood S. Panigrahy 《Agricultural Water Management》2009,96(7):1096-1104
Individual effect of different field scale management interventions for water saving in rice viz. changing date of transplanting, cultivar and irrigation schedule on yield, water saving and water productivity is well documented in the literature. However, little is known about their integrated effect. To study that, field experimentation and modeling approach was used. Field experiments were conducted for 2 years (2006 and 2007) at Punjab Agricultural University Farm, Ludhiana on a deep alluvial loamy sand Typic Ustipsamment soils developed under hyper-thermic regime. Treatments included three dates of transplanting (25 May, 10 June and 25 June), two cultivars (PR 118 inbred and RH 257 hybrid) and two irrigation schedules (2-days drainage period and at soil water suction of 16 kPa). The model used was CropSyst, which has already been calibrated for growth (periodic biomass and LAI) of rice and soil water content in two independent experiments. The main findings of the field and simulation studies conducted are compared to any individual, integrated management of transplanting date, cultivar and irrigation, sustained yield (6.3-7.5 t ha−1) and saved substantial amount of water in rice. For example, with two management interventions, i.e. shifting of transplanting date to lower evaporative demand (from 5 May to 25 June) concomitant with growing of short duration hybrid variety (90 days from transplanting to harvest), the total real water saving (wet saving) through reduction in evapotranspiration (ET) was 140 mm, which was almost double than managing the single, i.e. 66 mm by shifting transplanting or 71 mm by growing short duration hybrid variety. Shifting the transplanting date saved water through reduction in soil water evaporation component while growing of short duration variety through reduction in both evaporation and transpiration components of water balance. Managing irrigation water schedule based on soil water suction of 16 kPa at 15-20 cm soil depth, compared to 2-day drainage, did not save water in real (wet saving), however, it resulted into apparent water saving (dry saving). The real crop water productivity (marketable yield/ET) was more by 17% in 25th June transplanted rice than 25th May, 23% in short duration variety than long and 2% in irrigation treatment of 16 kPa soil water suction than 2-days drainage. The corresponding values for the apparent crop water productivity (marketable yield/irrigation water applied) were 16, 20 and 50%, respectively. Pooled experimental data of 2 years showed that with managing irrigation scheduling based on soil water suction of 16 kPa at 15-20 cm soil depth, though 700 mm irrigation water was saved but the associated yield was reduced by 277 kg ha−1. 相似文献
6.
A series of substituted 4-methylcoumarins was synthesised and the members tested for their toxicity towards mycelial growth of seven phytopathogenic fungi in culture. Rhizoctonia solani, Alternaria alternata and Fusarium solani exhibited maximum sensitivity to these compounds whereas Pythium aphanidermatum, Colletotrichum falcatum, Drechslera oryzae and Macrophomina phaseolina were relatively less sensitive. 6-Ethyl-3-n- propyl-7-hydroxy4-methylcoumarin ( I ) was relatively toxic towards all fungi except C. falcatum, P. aphanidermatum and M. phaseolina. The 6-n-butyl ( III ) and 6-(1, 1, 3, 3-tetramethylbutyl) ( VI ) derivatives were highly toxic to R. solani with EC50, values of lμg ml?1. 相似文献
7.
Starch has been the most popular and economic size material. Synthetic binders have also been developed to be used as size material to improve weaving loom efficiency. Some synthetic size materials have got restrictions in use mainly because of ecological reasons. In the recent years, many modifications have come up in the starch as a sizing agent. Different modification can give different properties, which can be suited for a particular application. In the present study, for comparative analysis of different varieties of natural starch, modified starch and synthetic size material have been evaluated and mechanical properties like cohesion power, adhesion power, abrasion resistance, bending rigidity etc. were studied. PVA shows best properties among all size material. Among modified starch, starch ester shows better properties. 相似文献
8.
The effects of hybridization of glass fibre on oil palm empty fruit bunch (EFB) and recycled polypropylene-based composites are described in this paper. The compounding process involved extrusion followed by injection moulding technique to prepare the samples for characterizations. Fibre loading were considered as 40 % of the total weight of the blends and EFB:glass fibre ratio was maintained as 30:70, 50:50, 70:30 and 90:10. Two types of coupling agents of maleic anhydride-grafted polypropylene such as polybond-3200 and fusabond P-613 of different molecular weight and maleic anhydride level were used to improve the interfacial adhesion between the fibres and the matrix. Composites were characterized by density, melt flow index, tensile, Izod impact and flexural testing. Morphological images of the fractured surfaces of the composites were examined by field-emission scanning electron microscopy. Samples were also characterized by thermal tests such as thermogravimetric analysis and differential scanning calorimetry to evaluate the thermal and crystalline properties, respectively. Optimization of hybridization of the fibres and effect of coupling agents were evaluated in terms of various properties of the samples. The composite prepared with EFB:glass fibre ratio of 70:30 showed better reinforcing properties than that of others. 相似文献
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10.
Establishment of ornamental and aesthetic plants in hot, arid conditions of India is difficult due to the prevailing climatic, edaphic and biotic factors. Effect of turfgrass on the growth of ornamental plants in hot arid conditions has not been studied so far anywhere in the world. A study was conducted on the campus of Arid Forest Research Institute, Jodhpur, India to assess the performance of a few ornamental plant species in combination with turfgrass and without turfgrass with respect to different soil tilling intervals. Growth of plants was better with turfgrass than without turfgrass. We suggest adopting a soil tilling interval of 30 days to achieve optimum growth of ornamental plant species in terms of height and crown diameter. Our results can help reduce labor costs and achieving better landscapes in fewer days in hot urban conditions of Indian sub continent. 相似文献