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71.
Pahar, B. and Rai, A., 1997. The characterization of infectious bursal disease virus strains/isolates from field outbreaks in India. Veterinary Research Communications, 21 (4), 289-301Three infectious bursal disease virus (IBDV) isolates were adapted to culture in chick embryo fibroblast cells in which they produced a cytopathic effect. The isolates were identified as IBDV by virus neutralization tests using a standard hyperimmune serum against infectious bursal disease, physicochemical properties and their pathogenicity in chick embryos and chicks. The IBDV S394 strain was antigenically different from IBDV S194/IBDV S494 as well as from the IBDV Intermediate Georgia strain, one of the vaccine strains in use in India.  相似文献   
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Genetic Resources and Crop Evolution - The study on Himalayan allium spices was undertaken with specific reference to commercially important taxa belonging to the genus Allium viz. A. stracheyi...  相似文献   
74.
Excess moisture (water-logging) during the summer–rainy season is one of the major production constraints for maize (Zea mays L.) in a large area of Southeast Asia. Identification and development of genotypes capable of withstanding the stress conditions could be an ideal and affordable approach suitable for resource poor maize-growing farmers of such areas. We attempted to identify the most susceptible/critical crop stage(s) of maize for excess moisture stress, and to develop a screening technique and selection strategies for identification of germplasm tolerant to excess moisture stress. Among the four crop stages, i.e. early seedling (V2), knee-high (V7), tasseling (VT) and milk stage (R1), V2 was found to be highly susceptible, followed by the V7 stage. A screening technique (cup method) was developed/standardized, and was found to be an efficient technique for large-scale screening of maize genotypes against excess soil moisture stress. Germplasm was screened using this technique followed by field evaluation at the V7 growth stage (seventh leaf visible). Excess soil moisture stress severely affected various growth and biochemical parameters, impaired anthesis and silking, and eventually resulted in poor kernel development and yield. However, remarkable variability was found among the genotypes studied. Genotypes with good carbohydrate accumulation in stem tissues, moderate stomatal conductance, <5 days ASI, high root porosity, and early brace root development ability have been found to have good tolerance against the hypoxia/anoxia caused by excess soil moisture conditions.  相似文献   
75.
The colony growth of some phylloplane fungi of wheat viz. Alternaria alternata, Aspergillus favus, Amiger, Cladosportium cladosporioides, Curvularia lunata, Drechslera australiensis, Epicoccum purpurascens, Fusarium oxysporum, Penicillium chrysogenum and P. citrinum were studied in chamber fumigation experiments exposed to 2669 ± 105 μg SO2 m?3 and 708.33 ± 55 μg NH3 m?3 air, separately, for 10, 30 and 60 min. The colony growth of all the test fungi was significantly (P=0.01/0.005) inhibited on prolonged period of SO2/NH3 exposure. However, some of the test fungi namely A. favus, A. niger, E. purpurascens and F. oxysporum showed growth stimulation after 10 min exposure of SO2. Similarly, the growth of C. lunata and F. oxysporum increased only after 10 min exposure of NH3. The inhibitory effect of SO2/NH3 was directly correlated with the exposure times.  相似文献   
76.
Ali  Zafar  Rai  S. K.  Jan  Sami  Raina  Kavita 《Genetic Resources and Crop Evolution》2022,69(6):2011-2027
Genetic Resources and Crop Evolution - Drought stress is currently one of the major threats to the global food security as it primarily is the main cause behind yield loss and hence overall...  相似文献   
77.
European Journal of Plant Pathology - Symptoms of bunchy top, little leaf, leaf chlorosis with chlorotic streaks, leaf necrosis and stunted growth were noticed in two banana cultivars, Champa and...  相似文献   
78.
An experiment was conducted by planting Hardwickia binata Roxb. at 200, 400 and 800 trees ha???1, intercrops viz., Brassica campestris (mustard) and Glycine max (soybean) were sown from the second year onwards in winter and summer respectively at the National Research Centre for Agroforestry, Jhansi, U.P., India with the objectives of evaluating agrosilvicultural potential of the system and to study the effect of tree densities on ecophysiology of understorey crops. Tree growth was affected by both density and intercrop in the initial years of growth. Photosynthetic photon flux density (PPFD) available to the intercrops reduced with increasing densities. Transpiration rate and stomatal conductance in intercrops decreased due to the presence of trees. No significant changes in leaf temperature were observed till the fifth year of the growing season. Yield was significantly higher in pure crop in comparison with all the densities in mustard. Soybean yield under 200 trees ha???1 was comparable to that of the pure crop. Trees at the density of 200 trees ha???1 provided a conducive microenvironment to the intercrops.  相似文献   
79.
India's 2013 National Food Security Act identifies Anganwadi centers (the courtyard shelter) as responsible for ensuring the food and nutrition for mothers and children. This article proposes four essential reforms that must take place to revitalize the languishing Anganwadi system: (a) strengthen implementation of the Integrated Child and Development Services (ICDS) through greater outreach and education; (b) boost incentives for Anganwadi workers and Anganwadi health workers; (c) bring together different government stakeholders to provide the integrative framework needed; and (d) improve monitoring and evaluation of Anganwadis so as to better gauge not just performance of workers, but also health and nutrition outcomes among women and children.  相似文献   
80.
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