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71.
Twelve mouse monoclonal antibodies (MAbs) were developed against an Indian vaccine strain of foot and mouth disease virus (FMDV) type Asia-1 WBN 117/85. The MAbs were tested for their ability to bind to whole virus particle, trypsin-treated 146S (TT-146S) virus particle, sub-viral (12S and disrupted virus) antigens by ELISA and to neutralize virus infectivity in cell culture. Extensive characterization of MAbs revealed the existence of three different groups based on the binding of non-overlapping epitopes. Eight type Asia-1 specific MAbs (RF7, RF8, RD10, RE11, RC11, RC10/O, RB11 and RC10/M), which formed group 1 (G1), were found to bind a neutralizing, trypsin-sensitive (TS) and conformational epitope. Two MAbs (WB8 and WC3) in group 2 (G2) were found to bind a non-neutralizing, trypsin-resistant, conformational and 12S-specific epitope, which was intertypically conserved in all the four serotypes of FMDV (O, A, C and Asia-1) prevalent in India. Two MAbs (KG10 and KF10), which formed group 3 (G3), were found to be against a non-neutralizing, TS and conformational epitope, common to types Asia-1 and A. Members of G1 were IgG2a isotype, while those of G2 and G3 were IgG1 and IgG2b isotypes, respectively. Antigenic analysis of 31 FMDV type Asia-1 field isolates and two vaccine strains, using a panel of type Asia-1-specific MAbs, revealed antigenic similarity of the virus isolates tested and non-existence of neutralization escape mutants. The developed MAbs have practical utility, especially in the manufacture of FMD vaccine, diagnosis and FMDV characterization.  相似文献   
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73.
Field efficacies of two insect growth regulators (IGRs) at two recommended application rates, buprofezin at 370 and 555 g AI ha(-1) and lufenuron at 37 and 49 g AI ha(-1), were determined against the sweet potato whitefly, Bemisia tabaci (Gennadius), and the cotton bollworm, Helicoverpa armigera (Hübner), in experimental plots of cotton at the Directorate of Cotton Research, Faisalabad, Pakistan. Adverse effects of the IGRs on populations of associated arthropod predators, namely geocorids, chrysopids, coccinellids, formicids and arachnids, were also assessed. Both IGRs significantly reduced populations of B. tabaci at each application rate 24, 48 and 72 h after treatment, and higher doses were more effective than lower doses. Buprofezin was not effective against H. armigera at any tested dose for any time of treatment in any spray. Lufenuron applied at 37 and 49 g AI ha(-1) effectively suppressed H. armigera populations, resulting in significant reductions in crop damage. At lower doses, both IGRs appeared safe to predator populations, which did not differ significantly in IGR-treated versus untreated control plots. Population densities of formicids and coccinellids were significantly lower at high concentrations of both IGRs in treatment plots, possibly as a result of reduced prey availability. The potential role of buprofezin and lufenuron for control of B. tabaci and H. armigera in a spray programme and the likelihood of direct toxic effects of IGRs on predatory fauna of cotton are discussed.  相似文献   
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This paper analyzes the diversity, consumption and gathering patterns, and uses of wild edible plants among the tribal communities living in cold arid region of Indian Himalaya. Eco-geographically, extremely cold climate, open vegetation, strong afternoon winds and loose soils characterize the region. Wild edible plants have special significance in the livelihoods of tribal people particularly during harsh winters when nothing grows on field. We gathered information on 164 wild edible plant species belonging to 100 genera and 37 families sharing 14% of total plants species occurring here. Around 83% plant species were present in pure wild state while 17% were in semi wild state/cultivated occasionally. Wild plants are eaten more as vegetable and it was found that out of 101 plants used as vegetable, 57 are cooked and eaten and the rest (44) eaten raw. The species like Pinus gerardiana, Prunus armeniaca, Hippophae rhamnoides, Bunium persicum are harvested more for commerce in the downtown markets while Lepidium latifolium, Taraxacum officinale, Urtica hyperborea, Capparis spinosa, Fagopyrum tataricum, Malva verticillata, and Rhodiola heterodonta are preferred for their medicinal and nutritional properties locally. Infrastructure development, more tourists flow, agricultural intensification, more jobs and business opportunities have led to rapid changes in the life styles and food habits of the people. Consequently, the age-old tradition of gathering wild edible plants is fading particularly among younger generations. Nevertheless, people do realize the importance of wild edible plants, and therefore to harness the benefits of this unique diversity participatory management and conservation programs, investigations on nutritional and pharmacological attributes, and regulated market support for some important WEPs have taken up in the region.  相似文献   
76.
The present paper reports the development of novel braided structures using polyamide 6.6 fibers for application as artificial anterior cruciate ligaments (ACLs). The developed structures were circular braids, axially reinforced with either a number of core yarns or braided structures. Tensile behavior of these structures was characterized and the effects of number of axial yarns or braids and, the number of yarns used in the axial braids were thoroughly investigated. From the experimental results, it was observed that the braided structures with axial braids could mimic the load-elongation behaviour of native ACL. The average breaking extension and strain at toe region were 30 % and 4.3 % respectively, which are in the range of native ACLs. The maximum breaking force and stiffness achieved with 7 axial braids, each produced using 6 yarns were 274 N and 13.5 N/mm respectively and, both breaking force and stiffess showed linear increase with the number of axial braids as well as number of yarns used in the axial braids. Therefore, it is possible to design an artificial graft using these novel braided sturctures with mechanical properties similar to that of native ACLs, through adjustment of these structural parameters, as these braided structures have much smaller diameter (0.5 mm) than native ACLs (11 mm).  相似文献   
77.
Asian cultivated rice shows allelic variation in sodium transporter, OsHKT1;5, correlating with shoot sodium exclusion (salinity tolerance). These changes map to intra/extracellularly-oriented loops that occur between four transmembrane-P loop-transmembrane (MPM) motifs in OsHKT1;5. HKT1;5 sequences from more recently evolved Oryza species (O. sativa/O. officinalis complex species) contain two expansions that involve two intracellularly oriented loops/helical regions between MPM domains, potentially governing transport characteristics, while more ancestral HKT1;5 sequences have shorter intracellular loops. We compared homology models for homoeologous OcHKT1;5-K and OcHKT1;5-L from halophytic O. coarctata to identify complementary amino acid residues in OcHKT1;5-L that potentially enhance affinity for Na+. Using haplotyping, we showed that Asian cultivated rice accessions only have a fraction of HKT1;5 diversity available in progenitor wild rice species (O. nivara and O. rufipogon). Progenitor HKT1;5 haplotypes can thus be used as novel potential donors for enhancing cultivated rice salinity tolerance. Within Asian rice accessions, 10 non-synonymous HKT1;5 haplotypic groups occur. More HKT1;5 haplotypic diversities occur in cultivated indica gene pool compared to japonica. Predominant Haplotypes 2 and 10 occur in mutually exclusive japonica and indica groups, corresponding to haplotypes in O. sativa salt-sensitive and salt-tolerant landraces, respectively. This distinct haplotype partitioning may have originated in separate ancestral gene pools of indica and japonica, or from different haplotypes selected during domestication. Predominance of specific HKT1;5 haplotypes within the 3 000 rice dataset may relate to eco-physiological fitness in specific geo-climatic and/or edaphic contexts.  相似文献   
78.
Journal of Crop Science and Biotechnology - Plant productivity is significantly affected by several environmental stresses. Excess amount of salt in the soil is one of the environmental stresses...  相似文献   
79.
A large global land area is affected by saline, alkali (sodic), and acid soil conditions. Cool season food legumes are important crops in many countries with such adverse soils. Tolerant genotypes have been identified in many crops, including legumes. However, very little has been published on selection of tolerant cool season food legume crops. The inadequate knowledge and understanding of the responses of cool season food legume crops to these abiotic stresses, necessitates action by a collaborative network of interdisciplinary teams to make rapid progress in identifying tolerant germplasm and developing cultivars better adapted to unfavorable soil conditions.  相似文献   
80.
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