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31.
The present study focuses on hybridization program involving two species belonging to two different vandaceous genera, viz., Ascocentrum ampullaceum (Roxb.) Schltr. var. auranticum, a narrow endemic orchid of Manipur and Vanda coerulea Griff., an endangered orchid of Appendix I of CITES (Convention on International Trade in Endangered Species of Wild Fauna and Flora), to synthesize the primary hybrid genus with intermediate and improved characters in the F1 generation. Observations on the crossability in the present bigeneric cross between V. coerulea and A. auranticum had been achieved with 60% success when V. coerulea was taken as female parent. Murashige and Skoog (MS) basal medium at half-strength was effective for the development of the hybrid seedlings of V. coerulea × A. auranticum followed by Vacin and Went (VW) and Knudson C (KC) media. The best response of seedling growth was observed on MS medium at half-strength supplemented with 2.3 μM kinetin + 0.5 μM α-naphthalene acetic acid with maximum shoot height (2.7 cm), leaf number (4.6) and root number (4.1) after 150 days of inoculation. The survival percentage and growth performance of the seedlings were found to be higher (80% survival) in potting substrate consisting of brick:charcoal in the ratio 2:1 mulched with moss (Sphagnum sp.) than in potting substrate consisting of brick:charcoal:tree fern in the ratio 2:1:1. The first flowering was observed in the hybrid seedlings of V. coerulea × A. auranticum after 2 years of transfer to the ex vitro environment. Morphologically, the flowers differed from that of the parents clearly showing the success of the hybridization experiment. Registration of the hybrid has been made with the Royal Horticultural Society with the nomenclature Ascocenda ‘Kangla’ (No. T128725). 相似文献
32.
Asheesh Shanker Aarti BhargavaRicha Bajpai Stuti SinghSucharita Srivastava Vinay Sharma 《Scientia Horticulturae》2007
Characterization of microsatellites is extremely important for the development of molecular markers. Here, we present the detection and abundance of microsatellites or simple sequence repeats (SSRs) in UniGene sequences of Citrus sinensis. A total of 427 SSRs were mined in 8786 UniGene sequences downloaded from National Center for Biotechnology Information (NCBI). Depending on the repeat units, the length of SSRs ranged from 14 to 21 for mono-, 14 to 48 for di-, 18 to 48 for tri-, 24 to 40 for tetra- and 42 bp for hexa-nucleotide repeats. Average density of SSRs (1SSR/12.92 kb of 5518.71 kb sequences mined) suggests that only 4.43% of sequences contained SSRs. Di-nucleotide repeats were most frequent repeat type (49.41%) followed by tri-nucleotide repeats (41.45%). An attempt was made to design primer pairs for 427 identified SSRs but these were found only for 216 sequences. The positions of SSRs with respect to open reading frame (ORF) detected and annotation of sequences containing SSRs were also carried out to assign function to each of the sequences. 相似文献
33.
Analysis and in vivo assay of B. abortus agglutinating and non-agglutinating antibodies 总被引:2,自引:0,他引:2
Studies were made of physicochemical and immunochemical characteristics of Brucella abortus agglutinating and non-agglutinating antibodies in the sera of cattle repeatedly injected with living B. abortus (Strain 1119). Both agglutinating and non-agglutinating antibody were shown to be IgG1, and by immunodiffusion against rabbit anti-cattle gamma-globulin, agglutinating antibody gave a precipitation line of identity with that given by non-agglutinating antibody. Whilst agglutinating antibody increased clearance of antigen from the blood of passively protected mice, non-agglutinating antibody did not enhance clearance. Determination of the spleen infection index in mice pre-treated with agglutinating and non-agglutinating antibody showed that in animals passively immunized with non-agglutinating antibody the number of living (infecting) bacteria was approximately 4 times higher than in the case of agglutinating antibody. The possible potentiation of chronic B. abortus infection by non-agglutinating antibody is discussed. 相似文献
34.
Rao GS Ramesh S Ahmad AH Tripathi HC Sharma LD Malik JK 《Veterinary research communications》2001,25(3):197-204
The pharmacokinetics of enrofloxacin and its active metabolite ciprofloxacin were investigated in goats after a single intramuscular administration of enrofloxacin at 2.5 mg/kg body weight. The plasma concentrations of enrofloxacin and ciprofloxacin were determined simultaneously by a HPLC method. The peak concentrations (C
max) of enrofloxacin (1.13 g/ml) and ciprofloxacin (0.24 g/ml) were observed at 0.8 and 1.2 h, respectively. The elimination half-life (t
1/2), volume of distribution (V
d(area)), total body clearance (ClB) and mean residence time (MRT) of enrofloxacin were 0.74 h, 1.42 L/kg, 1329 ml/h per kg and 1.54 h, respectively. The t
1/2, area under the plasma concentration–time curve (AUC) and the MRT of ciprofloxacin were 1.38 h, 0.74 g h/ml and 2.73 h, respectively. The metabolic conversion of enrofloxacin to ciprofloxacin was appreciable (36%) and the sum of the plasma concentrations of enrofloxacin and ciprofloxacin was maintained at or above 0.1 g/ml for up to 4 h. Enrofloxacin appears to be useful for the treatment of goat diseases associated with pathogens sensitive to this drug. 相似文献
35.
Alexander Ciji Prakash Sharma Manchi Rajesh Biju S. Kamalam Annu Sharma Pragyan Dash M. S. Akhtar 《Aquaculture Research》2021,52(1):130-141
Periodic changes in reproductive hormone levels, gonadal histology and gonadosomatic index (GSI) of snow trout, Schizothorax richardsonii, were examined to ascertain annual cycle of gonadal development and reproductive status in their natural habitat. In females, there were coherent changes in plasma 17β‐oestradiol and vitellogenin along with GSI, oocyte maturation and vitellogenic progression, collectively indicating two distinct maturation peaks during the months of September and February. Coinciding with this, in males, plasma 11‐keto testosterone was also noticeably higher during September and February, with highest GSI values in September. However, plasma 17α, 20β‐dihydroxyprogesterone levels in males were found to be persistently high from September to February. This observation suggests the potential presence of matured oozing males over a longer period, unlike in females. Overall, the close association between reproductive hormone levels, GSI and gonadal maturation stages in males and females (particularly, the presence of postovulatory follicle complexes) with apparent natural synchronization clearly indicates that S. richardsonii breeds twice in a year, possibly during late September to early November and late February to early April in the coldwater riverine habitats of the Indian Himalayan region. 相似文献
36.
Chitra Nehra Avinash Marwal Rakesh Kumar Verma Megha Mishra Pradeep Sharma 《The Journal of Horticultural Science and Biotechnology》2019,94(4):475-480
India is one of the world’s largest producers of papaya. Viruses, mainly begomoviruses and potyviruses, cause a significant loss in papaya production. The study described here has identified a new species of begomovirus and a new species of betasatellite infecting Carica papaya in India. The sequences of the begomovirus and betasatellite show 90.03% nucleotide sequence identity to an isolate of Radish leaf curl virus and 92.25% identity to an isolate of Tomato leaf curl betasatellite, respectively. Maximum likelihood phylogenetic tree of begomovirus sequence of isolate DP2 (KX353622) showed distant relationships with previously characterised begomoviruses. Recombination analysis proposed six recombination breakpoints in begomovirus genome with other geographical begomovirus isolates. 相似文献
37.
Paddy and Water Environment - The paddy straw was collected in the form of bales with three mechanical process CI (stubble shaver + rectangular baler), CII (stubble... 相似文献
38.
Luke Randall Katharina Heinrich Robert Horton Lucy Brunton Matthew Sharman Victoria Bailey-Horne Meenaxi Sharma Ian McLaren Nick Coldham Chris Teale Jeff Jones 《Research in veterinary science》2014
Waste milk samples from 103 farms in England and Wales were examined for the presence of β-lactam antibiotics and ESBL-producing Enterobacteriaceae. Approximately 10 months after the initial sampling, further waste milk, environmental and faecal samples from farms shown to be positive for CTX-M Escherichia coli were investigated further. Isolates with an ESBL phenotype were tested by PCR for the presence of blaCTX-M, blaOXA, blaSHV and blaTEM genes. Isolates positive for blaCTX-M were sequenced to determine CTX-M type. Representative isolates were further examined by PFGE, plasmid replicon typing and serotyping. Of particular interest, 21.4% of waste milk samples contained residues of the cephalosporin cefquinome, which was significantly associated with CTX-M bacteria. Such bacteria occurred in 5.8% of the waste milk samples (including 3.9% CTX-M E. coli). CTX-M types identified were 1, 14, 14b and 15, but none of the E. coli were serotype O25, the serotype of the human pandemic strain. 相似文献
39.
The role of excretory-secretory metabolites of Fasciola gigantica in modulating the delayed type of hypersensitivity in the host (rats) was investigated. Eighteen rats of either sex, aged 3-4 months, were assigned to three groups of 6 animals each. Rats in group 1 served as non-inoculated controls and each rat in this group was administered only Freund's complete adjuvant on day 7. Animals in groups 2 and 3 were administered inoculation dose(s) of somatic F gigantica antigen (SFgA) and excretory-secretory F gigantica antigens (ESFgA) according to the experimental schedule. The delayed-type hypersensitivity was monitored by assessing alterations in the foot pad thickness, its histopathology and lymphocyte proliferation assay. It was observed that the ESFgA caused diminution in delayed-type hypersensitivity response to a significant level (p <0.01) against SFgA in rats. This finding was further confirmed by lower stimulation indices of peripheral blood mononuclear cell in rats sensitized with ESFgA prior to inoculation of SFgA (group 1) than in nonsensitized rats receiving only SFgA (group 2). 相似文献
40.
1. To detect polymorphism in various quail lines, Randomly Amplified Polymorphic DNA (RAPD) markers were tested and were found to be effective. 2. Twenty decamer primers were selected at random and tested, and 6 of these generated distinct polymorphic patterns between the quail lines. 3. Out of a total of 60 bands amplified using 6 selected primers, 19 (31.7%) were found to be polymorphic. 4. Genetic similarity within the lines ranged from 0.726 in HBW to 0.836 in KLQ. 5. Genetic similarity estimates between the populations ranged from 0.709 to 0.808. 相似文献