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41.
Eighty-one isolates presumptively identified as Pasteurella multocida from a variety of diseases in animals in Zimbabwe were subjected to biochemical characterization, capsular typing and RAPD analysis. The majority of isolates (over 80%) were assigned into named taxa and were predominantly P. multocida subsp. multocida and P. multocida subsp. septica, whilst the remainder were unassigned. Serogroup A was predominant among the three capsular types (A, B and D) of P. multocida detected. Three main RAPD clusters and three subclusters were observed among the majority of isolates (93.8%), whilst the remainder was found to be weakly related. Nine different groups of strains with similar RAPD profiles (100% similarity) were also observed. The reference strain of capsular serogroup F clustered with the reference strain of P. multocida subsp. septica, whilst all other serogroups clustered with reference strains of subsp. multocida and gallicida. Notably, serogroups A and D were observed to be closely related to the reference strain of subsp. multocida. The relationship between biotype, capsular type, host origin and disease manifestation was not clear-cut. However, most pig isolates of subsp. multocida clustered together as did most cattle isolates of subsp. multocida. RAPD tended to separate subsp. multocida from septica. 相似文献
42.
An efficient, in vitro clonal propagation protocol has been established for Gardenia latifolia Ait. using mature nodal explants on Murashige and Skoog (MS) medium fortified with cytokinins (BA/Kn/2-iP) (1.0–5.0 mg l?1) in combination with auxin IAA (0.5 mg l?1). Maximum bud break (87 %) with shoot number (7.2 ± 0.26) observed on MS medium supplemented with BA (4.0 mg l?1) and IAA (0.5 mg l?1). Maximum number of shoots (30 ± 0.46) with shoot length of (0.9 ± 0.03 cm) observed on MS medium supplemented with BA (2.0 mg l?1), Kn (2.0 mg l?1) and IAA (0.5 mg l?1). Further elongation of shoots (3.5 ± 0.06 cm) was achieved on MS medium supplemented with BA (1.0 mg l?1) and IAA (0.1 mg l?1). About 70 % of root induction occurred in half-strength MS medium supplemented with IBA (4.0 mg l?1) in 4–6 weeks. Further elongation of roots with average length (9.0 cm) was achieved in culture bottles containing vermiculite and ¼ strength MS salts. After their partial hardening in these bottles for 30 days they were transferred to pots containing a mixture of soil and vermicompost (1:1) for acclimatization. The acclimatized plantlets were established in the field successfully with 85 % survival rate. 相似文献
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Narinder S. Saini Jitender MohindrooShashi K. Mahajan PhD Mulinti RaghunathAshwani Kumar PhD Vandana SangwanTarunbir Singh PhD Navdeep SinghSimrat S. Singh DVM PhD Arun AnandKiranjeet Singh PhD 《Journal of Equine Veterinary Science》2013
This article describes the surgical management of uterine torsion by midline celiotomy and cesarean section on 12 mares presented with signs of colic to a teaching veterinary hospital. The mares were either in full term of gestation (n = 7) or in advanced stage of pregnancy (n = 5). Six mares were in first parity. Uterine torsion was diagnosed by per rectal and per vaginal examinations. For surgical intervention, mares were anesthetized using a combination of xylazine (1.1 mg/kg) and ketamine (2.2 mg/kg), intravenously. After intubation, the animals were maintained on halothane (n = 4) or isoflurane (n = 8) inhalation anesthesia. Midline celiotomy was performed, and foals were delivered by cesarean section. In 11 mares, before closing the abdominal wound, the uterus was detorted manually and confirmed for its normal position. Both anesthetic protocols using halothane and isoflurane were found satisfactory for surgical correction of uterine torsion. After long-term follow-up, the study reported 75.0% (9/12) survival rate for mares. One mare was euthanized because of devitalized, necrosed, and adhered uterus to the abdominal wall. Of the nine surviving mares, seven were successfully bred. Three foals were born alive, and only one could survive on long-term basis. Of the nine dead foals, two had umbilical cord torsion. 相似文献
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Kaushal Kishore Upreti Ravindra Mohan Bhatt Periyasamy Panneerselvam Lakki Reddy Varalakshmi 《International Journal of Fruit Science》2016,16(2):191-209
Effects of arbuscular mycorrhizal fungi (AMF) alone or in combination with bacterial consortium (AMF+BC) inoculation prior to induced salinity (NaCl @ 150 or 250 mM) were studied on root growth; plant biomass; leaf area; Na+ and K+ contents; leaf water potential (Ψw); osmotic potential (Ψπ); photosynthesis rate (Pn); and contents of chlorophyll, phytohormones, and polyamines in the grape rootstock ‘Dogridge’, popular among Indian vine growers. AMF inoculation in the NaCl untreated rootstocks plants increased root growth, root and shoot biomass, and leaf area and improved leaf Ψw, Ψπ, Pn, and chlorophyll content, and also countered the stress-induced decline in the NaCl treated plants. The abscisic acid (ABA), cytokinins, and polyamine-spermidine and spermine contents in the leaves of NaCl untreated or treated were significantly increased by the AMF inoculation. Among the treatments, AMF with BC was relatively more effective than AMF alone with respect to changes in above morpho-physiological characters. The results depicted that AMF (AMF alone or AMF+BC) inoculation significantly improved salinity tolerance of grape rootstock and tolerance is induced by improvements in plant water balance, K+:Na+ ratio, and Pn, besides distinct accumulations in ABA and polyamines-spermine and spermidine. The above findings have potential in suggesting the AMF usefulness in improving the efficacy of ‘Dogridge’ rootstock in grape cultivation under salt affected soils. 相似文献
49.
Aditya Pratap Umashanker Prajapati Chandra Mohan Singh Sanjeev Gupta Meenal Rathore Nupur Malviya Rakhi Tomar Ajeet Kumar Gupta Swapnila Tripathi Narendra Pratap Singh 《Plant Breeding》2018,137(3):235-249
Grain legumes, the important constituents of sustainability‐based cropping systems and energy‐limited vegetarian diets have long been the subject of scientific research. Tremendous technological strides were made in the so‐called orphan crops, in terms of both varietal improvement and generation of basic information. Despite recalcitrancy and high genotype dependency, in vitro culture techniques such as organogenesis, in vitro mutagenesis, embryo rescue and in vitro gene transfer have been deployed for improvement of several grain legumes and these played an important role in introgression of desirable genes from related and distant species and creation of additional genetic variability. Stable and reproducible regeneration protocols resulted in the development of genetically modified chickpea, pigeon pea, cowpea, mungbean, etc., while embryo rescue was deployed successfully for recovery of interspecific recombinants, a few of them exploited for the development of commercial cultivars. Nevertheless, doubled haploidy witnessed limited success and protoplast regeneration and in vitro mutagenesis remained of academic interest. The present review focuses on the progress, achievements, constraints and perspectives of using in vitro technology in grain legume improvement. 相似文献
50.
A. Josephrajkumar Chandrika Mohan J. Poorani Merin Babu Daliyamol V. Krishnakumar Vinayaka Hegde P. Chowdappa 《Phytoparasitica》2018,46(1):57-61
Scavenging action of Leiochrinus nilgirianus Kaszab (Coleoptera: Tenebrionidae) on sooty mould deposition on coconut palms due to heavy honeydew production by the invasive rugose spiralling whitefly, Aleurodicus rugioperculatus Martin (Hemiptera: Aleyrodidae), is reported for the first time from Kerala, India. Adult beetles, averaging 2.07?±?0.9 / leaflet, with a maximum of five beetles per leaflet, and immature stages were generally confined to the abaxial of the palm leaves during daytime, but were found feeding on sooty mould during morning hours in damp conditions. The specially aided adaptive leg features of L. nilgirianus with bristle-like hairs on the undersurface of tarsomeres probably aid in proper adhesion on sooty mould laden plant surface and well developed tarsal claws that perhaps assist swift movement on fungus-laden leaflets. On an average one adult beetle could clear 1–2 mm2 sooty mould laden area in a period of one minute. In situ habitat conservation of L. nilgirianus would help to reduce the sooty mould at no cost in the most natural and eco-friendly manner avoiding chemical management options and other expensive methods. 相似文献