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61.
Peste des petits ruminants (PPR) is an important viral disease of sheep and goats, endemic in India. The study was undertaken to characterize the local PPRV by sequencing fusion (F) protein and nucleoprotein (N) gene segments and phylogenetic analysis, so as to focus on genetic variation in the field viruses. Selected regions of PPRV genome were amplified from clinical samples collected from 32 sheep and goats by RT-PCR and the resulting amplicons were sequenced for phylogenetic analysis. The phylogenetic tree based on the 322bp F gene sequences of PPRV from five different locations clustered them into lineage 4 along with other Asian isolates. While the 425bp N gene sequences revealed a different pattern of branching, yielding three distinct clusters for Nigerian, Turkey and Indian isolates. Thus, classification of PPRV into lineages based on the N gene sequences appeared to yield better picture of molecular epidemiology for PPRV.  相似文献   
62.
Genetic Resources and Crop Evolution - Zea mays ssp. parviglumis is the progenitor of maize and assume to have tolerance against various biotic and abiotic stresses. It...  相似文献   
63.
Improving the level and stability of grain yield is the primary objective of wheat breeding programs in the Eastern Gangetic Plains (EGP) of South Asia. A regional wheat trial, the Eastern Gangetic Plains Yield Trial (EGPYT), was initiated by CIMMYT in collaboration with national wheat research programs in Bangladesh, Nepal, and India in 1999–2000 to identify wheat genotypes with high and stable grain yield, disease resistance, and superior agronomic traits for the EGP region. A set of 21 wheat experimental genotypes selected from a regional wheat screening nursery in South Asia, three improved widely grown cultivars (Kanchan, PBW343 and Bhrikuti), and one long-term cultivar (Sonalika) were tested at 9–11 sites in six wheat growing seasons (2000–2005) in the EGP. The 21 experimental genotypes were different in each year, whereas the four check cultivars were common. In each year, one or more of the experimental genotypes showed high and stable grain yield and acceptable maturity, plant height, and disease resistance compared to the check cultivars. Three improved cultivars have already been commercially released in the region through EGPYT and many germplasm lines have been used in the breeding programs as parents. Identification of wheat genotypes with high-grain yield in individual sites and high and stable yield across the EGP region underlines their value for regional wheat breeding programs attempting to improve grain yield and agronomic performance.  相似文献   
64.
Isolated mesophyll cells from leaflets of Arachis hypogaea can be cultured in a simple, defined liquid nutrient medium containing minerals, with an appropriate source of ammonia, sugar, 2,4-dichlorophenoxyacetic acid, and kinetin. The significance of such a simple medium in understanding the problems of cell metabolism, growth, and morphogenesis is discussed.  相似文献   
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66.
Digestibility of fiber components namely neutral detergent fiber (total content of cellwall) cellulose, hemicellulose and lignin are estimated in 14 healthy vegetarian men during adlibitum feeding and at 3 energy levels namely 2526, 2868 and 3290 kcals/day. Values of digestibility for adlibitum experiments were 34.17±2.3 for neutral detergent fiber (NDF), 30.1±3.9 for cellulose and 53.4±3.0 for hemicellulose and 8.1±2.6 for lignin. There was a considerable variability in digestibility of fiber components between individuals.  相似文献   
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68.
Plant-based phosphorus (P) remediation strategies have been suggested to reduce high P accumulation in soil. Eleven fodder soybean genotypes were evaluated to explore their potential for the removal of P from poultry manure-enriched soils. Field experiments were conducted at a site that had a history of heavy poultry manure applications. Green house experiments were conducted using the soils selected for field trials to confirm the results. Harvesting of whole plants, excluding roots of the genotypes, was done at the pod formation stages and plant samples were oven dried at 70°C for three days. The dry samples were ground and analyzed for total P content. Genotype 091734, provided the maximum P removal from amended and unamended soils. Fodder soybean genotypes could play an important role in the extraction of P from poultry manure-enriched soils, which are important from the ecological point of view.  相似文献   
69.
Wild pigs are a free-ranging invasive species capable of inflicting significant damage on rural property. Wildlife management personnel may benefit from understanding the negative societal impact of wild pigs. A statewide mail survey of randomly selected landowners was conducted in rural Tennessee counties known to have wild pigs. The economic value of damage caused by wild pigs in 2015 in these counties was estimated at $26.22 million, whereas the cost incurred in control and eradication was $2.09 million. Input-output modeling of damage in these counties on the state’s economy showed $32.8 million in lost industrial output, $4.6 million in lost labor income, and 332 jobs or job equivalents affected. Findings are useful in understanding the types of damage, and the extent of these impacts on the rural economy. They could also facilitate comparing the expected benefit with the cost of control programs in Tennessee and comparable areas facing similar invasions from wild pigs.  相似文献   
70.
The importance of reduced tillage in sustainable agriculture is well recognized. Reduced-tillage practices (which may or may not involve retention of crop residues) and their effects differ from those of conventional tillage in several ways: soil physical properties; shifts in host–weed competition; soil moisture availability (especially when sowing deeply or under stubble); and the emergence of pathogen populations that survive on crop residues. There may be a need for genotypes suited to special forms of mechanization (e.g. direct seeding into residues) and to agronomic conditions such as allelopathy, as well as specific issues relating to problem soils. This article examines issues and breeding targets for researchers who seek to improve crops for reduced-tillage systems. Most of the examples used pertain to wheat, but we also refer to other crops. Our primary claim is that new breeding initiatives are needed to introgress favourable traits into wheat and other crops in areas where reduced or zero-tillage is being adopted. Key traits include faster emergence, faster decomposition, and the ability to germinate when deep seeded (so that crops compete with weeds and use available moisture more efficiently). Enhancement of resistance to new pathogens and insect pests surviving on crop residues must also be given attention. In addition to focusing on new traits, breeders need to assess germplasm and breeding populations under reduced tillage. Farmer participatory approaches can also enhance the effectiveness of cultivar development and selection in environments where farmers’ links with technology providers are weak. Finally, modern breeding tools may also play a substantial role in future efforts to develop adapted crop genotypes for reduced tillage.  相似文献   
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