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91.
The effects of total electrolyte concentrations of the equilibrium solutions (t.e.c.) on Ca2+-Na+ exchange equilibria in two soil samples (high and low in organic matter, clay content and CEC) were studied. Homoionic (Na+-saturated) soil samples were equilibrated with solutions having a large range in sodium adsorption ratio (SAR) at 25, 50, 75 and 100 meq. 1-1 t.e.c. The exchange equilibria data were analysed, using a thermodynamic approach and the selectivity coefficients of Gapon (1933), Vanselow (1932) and Krishnamoorthy et al. (1948) (KG, KV and KKDO). At a given proportion of Ca2+: Na+ in the equilibrium solution, the development of the exchangeable sodium percentage (ESP) in both soil samples increased with the increase in t.e.c. At a given SAR, the effect of t.e.c. on the development of ESP was less on a soil sample with high organic matter (O.M.), clay content and cation exchange capacity (CEC) than on a soil sample with low O.M., clay content and CEC. The values of exchange selectivity coefficients decreased with the increase in t.e.c, and did not remain constant throughout the exchange isotherm for any of the t.e.c. tried.  相似文献   
92.
This study was conducted to compare the efficacy of combinations of morphine, dexmedetomidine and maropitant in preventing the changes in electroencephalographic (EEG) indices of nociception in anaesthetized dogs subjected to a noxious electrical stimulus. In a crossover study, eight healthy adult dogs were randomly allocated to four groups: Mor: morphine 0.6 mg/kg; Dex + Mor: morphine 0.3 mg/kg + dexmedetomidine 5 μg/kg; Maro + Mor: morphine 0.3 mg/kg + maropitant 1 mg/kg; and Dex + Maro + Mor: morphine 0.2 mg/kg + dexmedetomidine 3 μg/kg + maropitant 0.7 mg/kg. Following intramuscular administration of test drugs in a minimal anaesthesia model, a supramaximal electrical stimulus (50 V at 50 Hz for 2 s) was applied and the EEG data were recorded. There were significant increases (p < .05) in the poststimulus median frequency (F50) only in groups Mor and Maro + Mor. Dex + Mor group had a significantly lower change in F50 and F95 compared to all other treatment groups. There was no correlation of the changes in EEG frequencies with blood plasma concentration of the drugs during and after noxious stimulation. Combination of dexmedetomidine and morphine was most effective in abolishing the changes in EEG indices in response to a noxious stimulus indicating a supra-additive interaction between these two drugs.  相似文献   
93.
Natural occurrence of mosaic disease was observed on basil (Ocimum sanctum L.) in Aligarh, U. P., India, during 2008. The disease could be transmitted by sap inoculations from naturally infected O. sanctum to O. sanctum and some test plant species. Cucumber mosaic virus (CMV) was detected by RT-PCR using coat protein gene specific primers of CMV (Acc. AM180922 & AM180923), which resulted in the expected size ~650 bp amplicon in infected samples. The amplicon was cloned, sequenced and data were deposited in GenBank Acc. EU600216. The sequence data analysis revealed 97–99% identities at both nucleotide and amino acid levels with the CMV strains of subgroup II reported worldwide. Based on the high sequence identities and close phylogenetic relationships with CMV subgroup II strains, the virus under study has been identified as a new isolate of CMV subgroup II and designated as CMV-Basil.  相似文献   
94.
A severe mosaic disease of pointed gourd (Trichosanthes dioica Roxb.) was observed with significant disease incidence in Gopalganj, India, during 2008. Begomovirus was detected from symptomatic leaf samples by polymerase chain reaction (PCR) using coat protein gene-specific primers of a well characterized begomovirus which revealed positive amplification of expected size ~800 bp DNA band. To confirm begomovirus association, the complete DNA-A was amplified using three sets of begomovirus DNA-A primers. The amplicons were cloned, sequenced, and sequence of the complete DNA-A (2757 nt) was determined by combining the sequence data of all amplicons (Accession no. GQ268327). The sequence data showed 99–93% sequence identities and close phylogenetic relationships with isolates of Ageratum enation virus (AgEV). The begomovirus associated with mosaic disease of T. dioica was identified as an isolate of Ageratum enation virus, which is a new record from India.  相似文献   
95.
BACKGROUND: Vector‐borne plant disease management can be enhanced by deployment of antifeedants in addition to the use of broad‐spectrum neurotoxic insecticides. The effects of pymetrozine on Asian citrus psyllid (ACP), Diaphorina citri Kuwayama, feeding behaviour, survival and transmission of Candidatus Liberibacter asiaticus (Las), the presumed causal pathogen of huanglongbing, were investigated. RESULTS: Pymetrozine applied at 52 and 104 µg mL?1 to citrus plants [Swingle citrumelo (X Citroncirus webberi Ingram and Moore)] modified the feeding behavior of ACP and increased the amount of time spent performing non‐penetration behaviors while decreasing the time spent performing ingestion behaviors compared with the controls 1 day after treatment. However, the antifeedant effect of pymetrozine subsided 5 days after application. Pymetrozine reduced the survival of both adults and nymphs on treated plants compared with the control. However, it had a greater impact on survival of nymphs than on survival of adults. Pymetrozine applied at 52 and 104 µg mL?1 on Las‐infected ‘Valencia’ sweet orange plants [Citrus sinensis L. (Osbeck)] reduced acquisition (12 and 21% respectively) and transmission (11 and 18% respectively) of Las by feeding ACP adults compared with the controls; however, these reductions were not statistically significant. CONCLUSIONS: Pymetrozine exhibited moderate antifeedant effects by modifying the feeding behavior of ACP adults with short residual activity. The impact of pymetrozine on survival of nymphs was greater than on adults at the higher concentrations tested. Pymetrozine also reduced the acquisition and transmission of Las by feeding ACP adults up to 21 and 18%, respectively, compared with untreated controls. Copyright © 2010 Society of Chemical Industry  相似文献   
96.
A new variant of Potato spindle tuber viroid (PSTVd) was detected for the first time from dahlia grown in Japan. The dahlia isolate of PSTVd formed a quasi-species and a major sequence variant consisting of 361 nucleotides in length, including five substitutions, three insertions, and one deletion, when compared to the intermediate strain from potato. In bioassays with the new isolate, Rutgers tomato developed mild stunting and leaf curling.  相似文献   
97.
1. The inheritance of various plumage colour variants and their underlying interactions were investigated in a large flock of Japanese quail maintained at CARI (India) by conducting reciprocal crosses between four breeding stocks inheriting Pharaoh, White Breasted, White and Brown plumages, followed by test crosses. 2. Based on the proportion of plumage-colour types in the progeny, putative genotypes were determined for parents and offspring for each of the crosses. 3. The White and Brown phenotypes were attributed to the Panda (S) and Roux (Br) loci respectively in agreement with contemporary quail stocks. 4. The White Breasted plumage type present in our stock was caused by a novel mutation with dominant gene action at an autosomal locus that was not allelic to either Panda or the White feather locus. 5. A recessive epistatic action of the Panda locus (S) on White Breasted (Wb) resulted in a White colour phenotype. 6. A novel phenotype, White Breasted-Brown was co-expressed with the Br and Wb loci. 7. It was concluded that breeding for customized feather colour phenotypes in Japanese quail using colour mutations was feasible and would be advantageous in order to overcome the limitations of legislation to protect wildlife in India.  相似文献   
98.
This study involved cloning and sequencing of the coding regions of all 10 Toll-like receptor (TLR) genes of goat. Goat TLR 1-10 gene sequences revealed a high degree of nucleotide identity with sheep and cattle sequences (>90%) and 75-85% with pig, mouse and human sequences. At the amino acid level, 85-99% similarity was observed with sheep and cattle and 60-85% with pig, mouse and human. TLR9c DNA of goat showed the highest amino acid identity to that of sheep (99%) while TLR8 cDNA showed the lowest identity of 88.7% to that of sheep. Variations were seen in the number of leucine rich repeats (LRRs) of goat TLRs as compared to other ruminant species with maximum differences in the TLR3 gene. Phylogenetic analysis through molecular evolution and genetic analysis (MEGA) software and multi dimensional scaling revealed a high degree of conservation of goat TLRs with those from other species. However when the TIR domain of all the TLRs were compared, goat TLR7 TIR alone showed a high divergence of 19.3 as compared to sheep sequences. This is the first report of the full-length cDNA sequences of all the 10 TLR genes of goats which would be a useful tool for the study of evolutionary lineages and for phylogenetic analysis.  相似文献   
99.
ABSTRACT: Cyprinid herpesvirus 3 (CyHV-3) is the aetiological agent of a mortal and highly contagious disease in common and koi carp. The skin is the major portal of entry of CyHV-3 in carp after immersion in water containing the virus. In the present study, we used in vivo bioluminescence imaging to investigate the effect of skin mucus removal and skin epidermis lesion on CyHV-3 entry. Physical treatments inducing removal of the mucus up to complete erosion of the epidermis were applied on a defined area of carp skin just before inoculation by immersion in infectious water. CyHV-3 entry in carp was drastically enhanced on the area of the skin where the mucus was removed with or without associated epidermal lesion. To investigate whether skin mucus inhibits CyHV-3 binding to epidermal cells, tail fins with an intact mucus layer or without mucus were inoculated ex vivo. While electron microscopy examination revealed numerous viral particles bound on the fins inoculated after mucus removal, no particle could be detected after infection of mucus-covered fins. Finally, anti-CyHV-3 neutralising activity of mucus extract was tested in vitro. Incubation of CyHV-3 with mucus extract reduced its infectivity in a dose dependent manner. The present study demonstrates that skin mucus removal and epidermal lesions enhance CyHV-3 entry in carp. It highlights the role of fish skin mucus as an innate immune protection against viral epidermal entry.  相似文献   
100.
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