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61.
Organics, biological, and inorganic fertilizers play a crucial role for improving crop yield and soil properties. Accordingly, we assessed their impact on yield, microbial activities, and transformations of carbon (C), nitrogen (N), phosphorus (P), and sulfur (S) in soils under a 12-year-old intensively cultivated rice (Oriza sativa L.), mustard (Brassica juncea L.), sesame (Sesamum indicum L.) system with sole inorganic (NPK); NPK + farmyard manure (NPKF); NPK + green manure (NPKG) (Sesbania sesban L.), and NPK + green manure + bio-fertilizer (NPKGB) (Azotobacter chroococcum+ pseudomonas putida) treatments in sub-tropical India. The system yield was much higher with NPKF (23%) and NPKGB (18%) than that with NPK. Organic supplementation had a favorable influence on soil microbial biomass C (Cmic), N (Nmic), and activities of extracellular enzymes. Results of principal component and multiple regression analyses showed significant influence of Cmic on system yield (R2 = 91, = 0.001) and S availability (R2 = 62, = 0.001). Similarly, mineralizable N and acid phosphatase could predict significantly soil available N (R2 = 85, = 0.001) and P (R2 = 51; = 0.001), respectively. Results thus indicated that integrated nutrient management (NPKF/G) improved system yield, nutrient accumulation, and microbial activities in soils.  相似文献   
62.
从 Madhupur 林区的不同地点采集了 Acacia auriculi-formis A. Cunn. ex Benth., A. mangium Wild., Artocarpus het-erophyllus Lamk. C., Dalbergia sissoo Roxb. ex A. P. D., Euca-lyptus camaldulensis Dehnn., Hevea brasiliensis (Wild. ex Juss) Muell. Arg., Swietenia macrophylla King. and Tectona grandis L. 8个树种的根和根际土。采用简单常规的根围土壤真菌孢子分离、形态鉴定和树木细根染色、显微镜观察等方法,进行了孟加拉国Madhupur林区内不同森林树种中丛枝菌根多样性的研究。图2表2参46。  相似文献   
63.
This study investigates the effect of single leaf litter of Terminalia arjuna (Ta) and Prosopis juliflora (Pj), mixed leaf litters [Ta, Pj, Azadirachta indica (Ai) and Albizia procera (Ap)] and paddy straw (Ps; Oryza sativa) on chemical properties and microbial activities of slightly sodic (SS), moderately sodic (MS) and highly sodic (HS) soils during 1 year in vitro decomposition process. For this purpose, equal amount (60 g) of single leaf litter [Ta (C : N = 43) and Pj (C : N = 38)], mixed leaf litters [1/4 of Ta, Pj, Ai and Ap (C : N = 30)] and Ps (C : N = 107) was added to equal amount (600 g) of SS, MS and HS soils. After addition of litters, changes in soil organic carbon (SOC), available nitrogen (Nav), microbial biomass carbon, nitrogen, soil respiration, microbial quotient (Cmic : Corg) and metabolic quotient (qCO2) were observed at 2 months intervals for the whole year in greenhouse at constant soil moisture. The respective annual increase, at the end of the experiment, in SOC and Nav was highest in MS soil (40% and 45%), whereas soil microbial biomass and soil respiration showed decreasing trend from HS soil (39% and 29%) to SS soil (28% and 21%). The highest SOC was mineralized in the MS (42%) and HS (32%) soils containing litter of Ta; although greater (20%) accumulation of SOC in SS soil was noticed with mixed leaf litters. The study reveals that MS and HS soils comparatively showed fast decomposition of litters and significant increase in carbon, nitrogen and microbial activities. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
64.
Reasons for performing study: Two studies report variability in proliferation and limited adipocyte differentiation of equine peripheral blood‐derived adult mesenchymal stem cells, thus casting doubt on their adipogenic potential. Peripheral blood can be a valuable source of adult mesenchymal stem cells if cell culture conditions permissive for their adherence, proliferation and differentiation are defined. Hyperbaric oxygen treatment has been reported to mobilise haematopoietic progenitor stem cells into the peripheral blood in humans and mice, but similar experiments have not been done in horses. Objectives: To optimise cell culture conditions for isolation, propagation and differentiation of adult stem cells from peripheral blood and to assess the effect of hyperbaric oxygen treatment on adult stem cell concentrations. Methods: Peripheral blood was collected from the jugular vein of 6 research mares, and mononuclear cells were isolated. They were subjected to cell culture conditions that promote the adherence and proliferation of adult stem cells. The cells were characterised by their adherence, expression of cellular antigen markers, and trans‐differentiation. Each horse was subjected to 3 hyperbaric oxygen treatments, and stem cells were compared before and after treatments. Stem cells derived from adipose tissue were used as controls. Results: One‐third of the horses yielded viable stem cells from peripheral blood, positive for CD51, CD90 and CD105, and demonstrated osteocyte, chondrocyte and adipocyte differentiation. Hyperbaric oxygen treatment resulted in a significant increase in CD90‐positive cells. Horses that did not yield any cells pretreatment did so only after 3 hyperbaric oxygen treatments. Conclusions and potential relevance: Peripheral blood can be a valuable source of adult stem cells, if one can identify reliable equine‐specific markers, provide methods to increase the number of circulating progenitor cells and optimise cell culture conditions for growth and viability. Our findings are important for further studies towards technological advances in basic and clinical equine regenerative medicine.  相似文献   
65.
66.
In the lungworm-endemic areas of Kashmir, 6-10 week old lambs of Karnah and Kashmir Merino breeds were vaccinated with two doses of 50 kR gamma-irradiated larvae of Dictyocaulus filaria, given a month apart. Assessed on the basis of reduced prevalence and significantly lower faecal larval output over an eight-month observation period, vaccinated lambs showed a high degree of resistance to naturally acquired D. filaria infection. The results also show that vaccination against D. filaria provided some degree of protection against infection with other lungworm species.  相似文献   
67.
Summary Four groups of calves (A, B, C and D) each consisting of five calves were used for the present study. Group A calves were givenCorynebacterium parvum alone. Group B calves were inoculated with inactivated ground-up-tick supernate (GUTS) prepared fromHyalomma anatolicum anatolicum infected withTheileria annulata plusC. parvum. Group C received only inactivated GUTS. All the surviving calves of groups A to C were exposed on day 45 post-inoculation to a lethal tick challenge along with susceptible control calves of group D. All the calves of groups A and B withstood the challenge whereas all the calves of groups C and D died of theileriosis. Complement fixing antibodies were detected in calves of groups B and C. A significant decrease in neutrophils and a significant increase in monocytes was observed in calves of groups A and B. No significant changes were seen in other cell types. The results of this study demonstrated thatC. parvum alone may be used as an immunostimulant for producing non-specific resistance againstT. annulata.
Proteccion Del Ganado Contra La Infeccion DeTheileria annulata UtilizandoCorynebacterium parvum
Resumen Se utilizaron para el presente estudio, cuatro grupos de terneros (A, B, C y D), cada uno conformado por cinco animales. Los terneros del grupo A fueron inoculados conCorynebacterium parvum únicamente. El grupo B, se inoculó con un sobrenadante inactivado de garrapatas molidas preparado deHyalomma anatolicum anatolicum infectadas conTheileria annulata másC. parvum; el grupo C recibió molido de garrapatas inactivado. Todos los terneros sobrevivientes de los grupos A y C fueron expuestos, a los 45 días de la inoculación, a una descarga letal de garrapatas infectadas, como tambien los terneros del grupo D. Todos los terneros de los grupos A y B sobrevivieron la descarga, mientras que los animales de los grupos C y D murieron de theileriosis. Se detectaron anticuerpos fijadores de complemento, en terneros de los grupos B y C. Los resultados demuerstran que elC. parvum solo, podría utilizarce como inmunoestimulante para crear resistencia no específica contraTheileria annulata.

Protection Des Bovins Contre L'infection ATheileria annulata Par L'utilisation DeCorynebacterium parvum
Résumé Quatre groupes de veaux (A, B, C et D), chacun composé de cinq veaux, ont été utilises dans la présente étude. On a administré desCorynebacterium parvum uniquement aux veaux du groupe A. Les veaux du groupe B ont été inoculé avec le surnageant de broyat de tique (SBT préparé à partir deHyalomma anatolicum anatolicum infecté parTheileria annulata et avec duC. parvum. Le groupe C a reçu seulement du SBT inactivé. Tous les veaux des groupes A à C qui avaient survécu ont été exposés le 45e jour après inoculation à une épreuve léthale de tiques avec les veaux du groupe D. Tous les veaux des groupes A et B ont résisté à l'épreuve tandis que les veaux des groupes C et D sont morts de theileriose. Des anticorps fixant le complément ont été décelés chez des veaux des groupes B et C. Les résultats de cette étude ont démontré queC. parvum seule peut être utilisée comme immunostimulant pour créer une résistance non spécifique àT. annulata.
  相似文献   
68.
The osmotic fragility of erythrocytes in lambs experimentally infected with Dictyocaulus filaria was studied weekly for 71 weeks. In acute infection, the erythrocytic fragility increased from the third week of infection onwards, reached its peak by the eleventh week and declined thereafter. However, in the chronic immune-carrier stage, this increase in the fragility did not return to normal until the end of the experiment. This enhanced fragility showed a positive correlation with the faecal larval count, worm burden and the extent of lung damage in lambs.  相似文献   
69.
Groups of Theileria annulata infected Hyalomma anatolicum anatolicum adults prefed on a calf for 1 to 6 days were separately ground in tissue culture medium-199, supplemented with bovine albumin powder, Fraction-V. Supernatant fluid was collected, made up with additional medium, so that each millilitre represented material from 25 ticks, and was injected subcutaneously into groups of cross-bred male calves. The results indicated that ground-up tick supernate (GUTS) prepared from unfed ticks was not infective, whereas that prepared from 1 to 6 days prefed ticks was infective. GUTS prepared from 3 days prefed ticks appeared to contain highest infectivity and 1 ml of it induced fatal theileriosis.  相似文献   
70.
In Europe, the English yew species (Taxus baccata L.) is endangered. Intensive human land-use, including forest management, has caused a decrease of the yew populations all over Europe. In Austria, gene conservation forests are used for the in situ conservation of populations of this rare tree species by silvicultural treatments. In order to improve the conservation management in these gene conservation forests, this study addresses the relation between competition and viability of yew populations through the use of structural diversity indices. The structural indices, which include mingling, tree–tree distance, diameter, and tree height differentiation, were determined for a structural group of four trees as well as the neighbouring trees of the male and female yews at the monitoring plots on a regular grid in three gene conservation forests. Although the three study sites provided quite different environmental conditions for English yew, the vitality of each individual yew was influenced by the inter-specific competition of the neighbouring tree species at all sites. Low vitality was associated with a small mean distance to neighbours and large tree height differentiation. In conclusion, we suggest that a combination of different structural indicators is needed for an integrative assessment of conservation status in the gene conservation forests. This would help improve the evaluation of the impact management has on yew population viability.  相似文献   
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