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1.
Ten species of Lepadella Bory de St. Vincent, 1826, including one new species and one new form, are documented from North-Eastern India. Two of these species are new records from this country and six are new reports from N.E. region. Comments are also made on the status and distribution of various Indian taxa. 相似文献
2.
John F. Lehmkuhl 《Plant Ecology》1994,111(1):29-43
Eight grassland associations with ten phases and two riverine forest associations were identified on the floodplains of Chitwan National Park in lowland Nepal. TwoThemeda arundinacea associations were primarily stable edaphic associations on mollic soils, often with aquic moisture regimes.Themeda associations were floristically similar to adjacent sal forest. Four mixed tall-grass associations primarily ofNarenga porphyrocoma, Saccharum bengalense, andSaccharum spontaneum were identified. These andThemeda arundinacea types were characterized by a very weak component of woody species. Two grass-shrub associations ofSaccharum bengalense andNarenga porphyrocoma with a strong woody species component typical of riverine forest were described.Trewia nudiflora-Bombax ceiba riverine forest and mixed riverine forest types also were identified on the basis of understory composition. Mixed tall-grass and grass-shrub associations appeared to represent early and late phases of grassland succession to riverine forest. Trajectories of succession are controlled primarily by fire and wildlife grazing. The classification refines the general classifications applied to the central Terai of Nepal and India, and should provide insight for classification of other Terai riverine grasslands.Abbreviations DS
Dabadghao and Shankarnarayan's 1973 grassland classification for India
- IMCY
Imperata cylindrica
- NAFA
Narenga fallax
- NAPO
Narenga porphyrocoma
- PHKA
Phragmites karka
- SABE
Saccharum bengalense
- SASP
Saccharum spontaneum
- THAR
Themeda arundinacea 相似文献
3.
B. K. Sharma 《Hydrobiologia》1990,199(1):29-33
Nine species and subspecies of the genus Testudinella are reported from North-Eastern India. Of these, six are new to India and eight to the North-Eastern region. Remarks are made on their distribution. 相似文献
4.
Hiranya Sudasinghe Tharindu Ranasinghe Kumudu Wijesooriya Rohan Pethiyagoda Lukas Rüber Madhava Meegaskumbura 《Ecology and evolution》2022,12(6)
Ricefishes of the genus Oryzias occur commonly in the fresh and brackish waters in coastal lowlands ranging from India across Southeast Asia and on to Japan. Among the three species of Oryzias recorded from peninsular India, two widespread species, O. carnaticus and O. dancena, have previously been reported from Sri Lanka based on museum specimens derived from a few scattered localities. However, members of the genus are widespread in the coastal lowlands of Sri Lanka, a continental island separated from India by the shallow Palk Strait. Although recent molecular phylogenies of Adrianichthyidae represent near‐complete taxon representation, they lack samples from Sri Lanka. Here, based on sampling at 13 locations representative of the entire geographic and climatic regions of the island''s coastal lowlands, we investigate for the first time the molecular phylogenetic relationships and phylogeography of Sri Lankan Oryzias based on one nuclear and two mitochondrial markers. Sri Lankan Oryzias comprise two distinct non‐sister lineages within the javanicus species group. One of these is represented by samples exclusively from the northern parts of the island; it is recognized as O. dancena. This lineage is recovered as the sister group to the remaining species in the javanicus group. The second lineage represents a species that is widespread across the island''s coastal lowlands. It is recovered as the sister group of O. javanicus and is identified as O. cf. carnaticus. Ancestral‐range estimates suggest two independent colonizations of Indian subcontinent and Sri Lanka by widespread ancestral species of Oryzias during two discrete temporal windows: late Miocene and Plio‐Pleistocene. No phylogeographic structure is apparent in Sri Lankan Oryzias, suggesting that there are no strong barriers to gene flow and dispersal along the coastal floodplains, as is the case also for other generalist freshwater fishes in the island. 相似文献
5.
6.
Prevalence of duodenal ulcer-promoting gene (dupA) of Helicobacter pylori in patients with duodenal ulcer in North Indian population 总被引:1,自引:0,他引:1
Arachchi HS Kalra V Lal B Bhatia V Baba CS Chakravarthy S Rohatgi S Sarma PM Mishra V Das B Ahuja V 《Helicobacter》2007,12(6):591-597
BACKGROUND: The duodenal ulcer (DU)-promoting gene (dupA) of Helicobacter pylori has been identified as a novel virulent marker associated with an increased risk for DU. The presence or absence of dupA gene of H. pylori present in patients with DU and functional dyspepsia in North Indian population was studied by polymerase chain reaction (PCR) and hybridization analysis. MATERIALS AND METHODS: One hundred and sixty-six patients (96 DU and 70 functional dyspepsia) were included in this study. In addition, sequence diversity of dupA gene of H. pylori found in these patients was analyzed by sequencing the PCR products jhp0917 and jhp0918 on both strands with appropriate primers. RESULTS: PCR and hybridization analyses indicated that dupA gene was present in 37.5% (36/96) of H. pylori strains isolated from DU patients and 22.86% (16/70) of functional dyspepsia patients (p < or = .05). Of these, 35 patients with DU (97.2%) and 14 patients with functional dyspepsia (81.25%) were infected by H. pylori positive for cagA genotype. Furthermore, the presence of dupA was significantly associated with the cagA-positive genotype (p < or = .02). CONCLUSION: Results of our study have shown that significant association of dupA gene with DU in this population. The dupA gene can be considered as a novel virulent marker for DU in this population. 相似文献
7.
Rupesh K. LUHARIYA ;Kuldeep K. LAL ;Rajeev K. SINGH ;Vindhya MOHINDRA ;Arti GUPTA ;Prachi MASIH ;Arvind K. DWIVEDI ;Rakhi DAS ;U. K. CHAUHAN ;J. K. JENA 《动物学报(英文版)》2014,(4):460-471
ATPase 6/8 gene (842 bp) of mitochondrial DNA was sequenced in Labeo rohita samples (n = 253) collected from nine rivers belonging to four river basins; Indus, Ganges, Brahmaputra and Mahanadi. Analysis revealed 44 haplotypes with high haplotype diversity (Hd) 0.694 and low nucleotide diversity (π) 0.001. The within population variation was larger (83.44%) than among population differences (16.56%). The mean Fsv value (0.166; P 〈 0.05) for overall populations revealed moderate level of genetic structuring in the wild L. rohita populations. The haplotype network presented a single clade for wild L. rohita population, from different rivers. Negative values for Fu's index (Fs), mismatch distribution analysis indicated period of expansion in L. rohita population. The time after recent expansion was estimated for each population, between 0.042 to 0.167 mya. The pattern of Isolation by Distance (IBD) was not significant (r = -0.113, P 〈 0.287), when all the sampling locations were compared (Mantel test), however, when an outlier (Indus, Brahmaputra and Mahanadi) was removed from the whole population set, a clear positive correlation between pairwise Fsv and geographic distance (Km) was seen. The analysis of data demonstrated that ATPase6/8 gene polymorphism is a potential marker to understand genetic population structure of wild L. rohita existing in different rivers. The study identified population substructure in wild L. rohita with common ancestral origin [Current Zoology 60 (4): 460--471, 2014]. 相似文献
8.
描述尖瘤属Acrocyrtus印度1新种,陈氏尖瘤A.cheni sp.nov.。 相似文献
9.
Palak Arora Zahoor A. Wani Tanveer Ahmad Phalisteen Sultan Suphla Gupta Syed Riyaz-Ul-Hassan 《Fungal biology》2019,123(5):373-383
A total of 266 endophytic fungal isolates were recovered from 1019 tissue segments of Glycyrrhiza glabra collected from four different locations in the North-Western Himalayas. The endophytes grouped into 21 genera and 38 different taxa. The host had strong affinity for the genus Phoma, followed by Fusarium. The species richness was highest at the sub-tropical location, followed by the sub-temperate location and the temperate locations, respectively. The tissue specificity of endophytes was also evident. Some endophytes showed potential antimicrobial activity against phyto-pathogens indicating that they may be helpful to the host in evading pathogens. All the endophytic taxa produced the plant growth promoting hormone, indole acetic acid (IAA), though in varying concentrations. None of these endophytes caused any symptoms of disease in co-cultivation with the tissue cultured plants. Further, all the endophytes had a positive influence on the phenolic and flavonoid content of the host. Three endophytes, Stagonosporopsis cucurbitacearum, Bionectria sp. and Aspergillus terreus also increased the host root (rhizome) and shoot growth visibly. Such endophytes are potential candidates for developing endophyte-based technologies for sustainable cultivation and enhanced productivity of G. glabra. This is the first report of community structure and biological properties of fungal endophytes associated with G. glabra. 相似文献
10.
Dev Karan Neena Dahiya Ashok K. Munjal Patricia Gibert Brigitte Moreteau Ravi Parkash Jean R. David 《Evolution; international journal of organic evolution》1998,52(3):825-831
Desiccation and starvation tolerance were measured along latitudinal transects in three Drosophilid species (Drosophila ananassae, D. melanogaster, and Zaprionus indianus) of the Indian subcontinent. In each case, significant latitudinal clines were observed; desiccation tolerance increased with latitude while starvation tolerance decreased. Such field observations suggest that desiccation and starvation tolerance are fitness related traits that are independently selected in nature and genetically independent. It was, however, difficult to relate these genetic changes with precise climatic variables, except winter temperature. The overall negative correlation between the two traits, which was evidenced in natural populations, contrasts with a positive correlation generally observed in various laboratory selection experiments and that also seems to exist between different species. These observations point to the difficulty of interpreting correlations among fitness-related traits when different evolutionary levels are compared, and also different sets of data, that is, field versus laboratory studies. 相似文献