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541.
Genetic analysis of river,swamp and hybrid buffaloes of north‐east India throw new light on phylogeography of water buffalo (Bubalus bubalis) 下载免费PDF全文
B.P. Mishra P.K. Dubey B. Prakash P. Kathiravan S. Goyal D.K. Sadana G.C. Das R.N. Goswami V. Bhasin B.K. Joshi R.S. Kataria 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2015,132(6):454-466
This study analysed buffaloes from north‐east India and compared their nuclear and mitochondrial DNA variations with buffaloes of mainland India, China, Mediterranean and South‐East Asia. Microsatellite genotypes of 338 buffaloes including 210 from six north‐east Indian buffalo populations and three mainland Indian breeds were analysed to evaluate their genetic structure and evolutionary relationships. Phylogenetic analysis and multidimensional scaling plot of pairwise FST revealed the clustering of all swamp‐type buffaloes of north‐east India with Lower Assamese (significantly hybrid type) buffaloes in one plane and all the mainland river buffaloes in another plane while the upper Assamese buffaloes being distinct from both these clusters. Analysis of mtDNA D‐loop region of 530‐bp length was performed on 345 sequences belonging to 23 buffalo populations from various geographical regions to establish the phylogeography of Indian water buffalo. The swamp buffaloes of north‐east India clustered with both the lineages of Chinese swamp buffalo. Multidimensional scaling display of pairwise FST derived from mitochondrial DNA data showed clustering of upper Assamese, Chilika and Mediterranean buffaloes distinctly from all the other Indian buffalo populations. Median‐joining network analysis further confirmed the distinctness and ancestral nature of these buffaloes. The study revealed north‐east region of India forming part of the wider hybrid zone of water buffalo that may probably extend from north‐east India to South‐East Asia. 相似文献
542.
An experiment was conducted on the three indica rice ( Oryza sativa L.) cultivars IR 42, CR 383-10 and FR 13A, which are susceptible to submergence, submergence-avoiding and tolerant to submergence, respectively. A deleterious effect of submergence was noted as both above-ground dry matter accumulation and chlorophyll content decreased during submergence and subsequent re-aeration. However, the rate of reduction was lower in the tolerant cultivar. The tolerant cultivar FR 13A maintained higher dry weight during submergence and subsequent re-aeration and accumulated lower proline and malondialdehyde contents than the other cultivars. The activities of the enzymes catalase, peroxidase and superoxide dismutase, expressed on a per g fresh weight of leaves basis, were higher in FR 13A than in the other cultivars, both under water and 24 h after the initiation of re-aeration. However, ascorbic acid oxidase activity was lower in FR 13A. The cultivar CR 383-10, which has the capacity to accumulate more above-ground dry matter under normal conditions, showed a greater elongation ability under submergence and was similar to the susceptible cultivar IR 42 in terms of enzyme activities and the other parameters investigated during submergence and subsequent re-aeration. 相似文献
543.
Recent advances in alien gene transfer in wheat 总被引:3,自引:0,他引:3
Summary The recent advances in alien gene transfer from distantly-related species into wheat are reviewed in the present paper. The main achievements during the last ten years include the great expansion of the range of wide hybridization and development of new techniques for production and characterization of wheat-alien chromosome translocations. Updated results of wide hybridization since 1983 and comprehensive characterization of wheat-alien translocation lines in our laboratory are compiled. The future outlook for alien gene transfer in wheat is also discussed. 相似文献
544.
Summary C-banding andin situ hybridization were used to determine the chromosomal constitution of the greenbug-resistant germplasm GRS 1204. The results showed that this line had the radiation-induced non-homoeologous wheat-rye translocation chromosomes T2AS-1RS·1RL and T2AL·2AS-1RS. C-banding analysis further revealed the presence of a wheat-Agropyron elongatum translocation chromosome T1BL·1BS-3Ae#1L in line GRS 1204, that was derived from Teewon. The greenbug resistance of line GRS 1204 is similar to that of line GRS 1201 that was earlier shown to have the greenbug resistance geneGb6 located on the 1RS arm of the wheat-rye translocation chromosome T1AL·1RS. BecauseGb6 in line GRS 1204 is present on one of the non-homoeologous translocation chromosomes, agronomically line GRS 1201 should be the better adapted source ofGb6 resistance and be used in cultivar improvement. 相似文献
545.
Summary Forty F6 lines, the two parental lines, and a susceptible check cultivar of wheat (Triticum aestivum L.) were inoculated in the young flag leaf stage with leaf rust (Puccinia recondita f.sp. tritici) and evaluated for latent period, receptivity, and uredinium size in a greenhouse experiment. Genotypic (rg) and phenotypic (rp) correlations between latent period and uredinium size were –0.81 and –0.62, respectively. A negative correlation (rg=–0.50, rp=–0.41) was found between latent period and receptivity and a positive correlation (rg=0.28, rp=0.26) between uredinium size and receptivity was found. Area under the disease progress curve (AUDPC) and final rust severity (FRS) obtained from a subsequent field study with common entries were negatively correlated with latent period and positively correlated with uredinium size. Correlations of receptivity with both AUDPC and FRS were not significant. The distributions of F6 family mean uredinia size and latent period were continuous between slow rusting and fast rusting parents: however, the distribution for receptivity was discrete. Narrow-sense heritability estimates were 63%, 57%, and 47% for uredinium size, latent period, and receptivity, respectively. Estimates of the minimum number of effective factors were three for latent period and three or four for the uredinium size and receptivity. The components are controlled by closely linked genes or due to pleotropic effects of the same gene.Abbeviations AUDPC -
Area under the disease progress curve
- FRS -
Final rust severity 相似文献
546.
Dash S Das SK Samal J Ojha PK Patra JK Thatoi H 《Veterinary research communications》2011,35(8):541-552
Specific and non-specific immune response to different doses of formalin killed whole cell vaccine of Aeromonas hydrophila to Indian major carp (Labeo rohita) was evaluated in laboratory condition. Three different doses (105 CFU/ml, 107 CFU/ml, 1010 CFU/ml) were administered (0.2 ml/fish) intraperitoneally for 1 month. Among the three doses, 1010 CFU/ml elicited the highest antibody and protective response followed by the doses 107 CFU/ml and 105 CFU/ml. Upon challenge with the virulent strain of A. hydrophila, the relative percentage of survival was recorded up to 80% at highest dose of 1010 CFU/ml. The non-specific responses, similar to the specific immune responses were also maximum at highest dose of 1010 CFU/ml. Similar to the specific immune responses, the non-specific responses were maximum at highest dose of 1010 CFU/ml. Therefore, dose containing 1010 CFU/ml of formalin killed cells was found to be the most effective dose for vaccination which increased the immunity in Indian
major carp (Labeo rohita) to a larger extent. 相似文献
547.
Cryptosporidium infection may have adverse effect in health and production potential of cattle herd. The exact profile of Cryptosporidium infection in bovine population of India in general, particularly from Kolkata is scarce. We here report systematic investigation of clinical and genetic profiling of promiscuous Cryptosporidium infection in selected representative cattle farms from Kolkata as well as some surrounding local areas. The current study was conducted in the period of October to September, 2000–2001 with 149 diarrhoeic and non-diarrhoeic cattle of different age groups from two Government cattle farms, Harringhata Cattle Unit and Kalyani State Livestock Farm and animals raised by local farmers. Among these 149 samples, diarrhoea was recorded in 79 cases (53%) and non-diarrhoeic in 70 (46.9%). Out of 149 faecal samples screened microscopically, 32.9% from diarrhoeic faecal samples and 7.1% from healthy faecal samples revealed the presence of oocysts. Cryptosporidium genus was confirmed by DNA typing with nested PCR. The PCR-RFLP analysis was carried out for genotype identification. In course of PCR-RFLP, unique band patterns were obtained in two of our samples. The unusual RFLP products were characterized by DNA sequencing and homology analysis with other reported variants. This is the first report of identification and characterization of such a variant from the area of present investigation. Further study will be required to understand the phylogenetic origin and functional significance in virulence and morbidity of this genotype. 相似文献
548.
In India, wheat is prone to being heavily infested with weeds, which cause considerable yield losses. Agronomic practices, including sowing method, influence weed interference in wheat growth. A herbicide mixture is usually more effective than a single herbicide for controlling a broad-spectrum of weeds. It may prevent weed species shift and delay resistance development in weeds. This study attempted to develop an integrated approach, combining a modified sowing method with applying a herbicide mixture for efficient weed management in wheat. We found that flat bed missing-row sowing resulted in significant reductions in: (i) the three-year mean population densities of grassy, broad-leaved and total weeds at 40 days after sowing (d.a.s), (ii) total weed population density and biomass (dry weight) at 60 d.a.s., compared to a mainly, furrow-irrigated raised bed system. Applying a tank-mix of fenoxaprop-p-ethyl at 0.08 kg/ha and isoproturon at 0.4 kg/ha applied 30 d.a.s. resulted in significant reductions in total weed population density and biomass, leading to a significant improvement in wheat growth and yield compared to either a weedy check or a regime of fenoxaprop-p-ethyl applied at 0.10 kg/ha. However, a combination of the flat bed missing-row sowing and tank-mix application of fenoxaprop-p-ethyl 0.08 kg/ha and isoproturon 0.4 kg/ha 30 d.a.s. resulted in higher wheat yield through better management of weeds compared with other sowing/ weed control combinations. 相似文献
549.
Babesia bigemina infection in yak (Poephagus grunniens L.): Molecular detection and characterization
B.C. Saravanan S. Das S.J. Siju A.K. Tewari M. Sankar M.A. Kataktalware K.P. Ramesha 《Veterinary parasitology》2013
Yaks contribute significantly in the Himalayan high land economy. Specific information on prevalence of babesiosis in yaks is lacking. A fast and reliable PCR assay targeting Babesia bigemina small subunit ribosomal RNA sequence (SS rRNA) was laboratory standardized for molecular detection of B. bigemina in yaks. Restriction digestion of the PCR amplified 675 bp target sequence with Vsp I confirmed the prevalent species of Babesia as B. bigemina. Nucleotide sequencing and phylogenetic analysis of PCR amplified 675 bp SS rRNA sequence revealed a close genetic relationship with other bovine isolates of B. bigemina. A PCR based survey involving 94 blood samples of yak from the National Research Centre on Yak, Dirang, Arunachal Pradesh detected infection in 5.32% of yak blood samples, which was significantly higher in comparison to microscope based detection of infection in 2.13% blood smears. This is the first report on sensitive PCR based detection of B. bigemina infection in yaks and PCR-RFLP and nucleotide sequence analysis based molecular characterization of the B. bigemina isolated from yaks. 相似文献
550.