PCR based molecular characterization of Nepenthes khasiana Hook. f.—pitcher plant

Nepenthes khasiana Hook. f. belonging to monotypic family Nepenthaceae is a rare, endangered, dioecious member of the carnivorous plant found in North-East India. The plant is endemic to the Indian state of Meghalaya and is distributed throughout the state from West Khasi hills to East Khasi hills, Jaintia hills and East, West to South Garo hills from 1,000 to ca. 1,500 m altitude. Multi-locus analysis using PCR based Random Amplified Polymorphic DNA (RAPD) and Inter Simple Sequence Repeats (ISSR) markers were used for the first time to assess the genetic diversities of N. khasiana Hook. f. collected from different parts of Meghalaya. It was observed that RAPD analysis showed more polymorphism than ISSR fingerprinting in revealing genetic polymorphism in N. khasiana Hook. f. The result of cluster analysis by using UPGMA method showed that the groups based on pooled RAPD–ISSR genetic similarity were more similar than the groups based on RAPD. Furthermore, genetic similarity reveals variability within the population at Jarain of Jaintia hills, while between populations the Baghmara region differs from the others with at least 40% dissimilarity. The results show a broad range of genetic diversity within the populations of N. khasiana Hook. f

Assessing genetic diversity of Tecomella undulata (Sm) - an endangered tree species using amplified fragment length polymorphisms-based molecular markers

Tecomella undulata is an important agro-forestry tree in the western parts of India, which has been included in the list of endangered plant species due to over exploitation. There is an urgent need to formulate appropriate conservation and breeding strategies to save this versatile tree. Quantification of genetic diversity in the existing populations of T. undulata prevalent in India, is an essential first step towards this objective. The present work was undertaken to investigate the utility of amplified fragment length polymorphism (AFLP) markers in the assessment of genetic diversity and phenetic relationship among 42 T. undulata plants collected from different regions of India. Eight AFLP primer combinations generated a total of 338 bands across the 42 T. undulata accessions screened. On an average, 42 AFLP fragments were amplified per reaction. Of the total 338 AFLP fragments, 71.7% was polymorphic across all the accessions. From the AFLP data, a similarity matrix based on Jaccard's coefficient was calculated which was used for constructing a phenetic dendrogram using UPGMA analysis. T. undulata accessions represented high levels of genetic variation as indicated by GS values ranging from 0.721 to 0.83, at which 42 T. undulata accessions grouped together. The pattern of grouping in the phenogram was highly consistent as indicated by high values of cophenetic correlation (r = 0.87, P = 1) as also by high bootstrap values at the key nodes. Principal correspondence analysis also Cited By since 1996 This article has been cited 0 times in Scopus. Inform me when this document is cited in Scopus: E-mail Alert Find related documents In Scopus based on On the Web based on title Document Type: Article View references (31) references authors keywords authors keywords Page 1 of 5 Scopus - Current Science: Assessing genetic diversity of Tecomella undulata (Sm.) - An endangered... 02/04/2008 http://www.scopus.com/scopus/record/display.url?view=basic&eid=2-s2.0-3 revealed that T. undulata accessions were scattered on the plot. Based on our study, it may be concluded that there is a high level of genetic diversity in T. undulata accessions analysed, which may be attributed to its out-crossing nature. Our study may be useful in identifying diverse genetic stocks of T. undulata, which may then be conserved on priority basis. Author Keywords AFLP; Conservation; Genetic diversity; Molecular makers; Tecomella undulata References (31) view in table layout Select: Page 1. (1982) The Wealth of India, 10, pp. 134-136. Publications and Information Directorate, CSIR, New Delhi, Anon 2. Jindal, S.K., Kackar, N.L., Solanki, K.R. Evaluation of Tecomella undulata (Sm.) SEEM germplasm from western Rajasthan in situ (1985) Trans. Indian Soc. Desert Technol. Univ. Cent. Desert Stud, 10, pp. 33-37. 3. Jindal, S.K., Solanki, K.R., Kackar, N.L. Phenology and breeding systems of Rohida (Tecomella undulata (Sm.) SEEM) (1985) Indian J. For, 8, pp. 317-320. 4. Jindal, S.K., Kackar, N.L., Solanki, K.R. Germplasm collection and genetic variability in Rohida (Tecomella undulata (Sm.) Seem) in western Rajasthan (1987) Indian J. For, 10, pp. 52-55. 5. Rao, A., Kiran-Bala, V., Lahiri, A.N., Bala, K. Influence of trees on microorganisms of aridisol and its fertility (1989) Indian For, 115, pp. 680-683. 6. Azam, M.M. Anti-HIV agents and other compounds from Tecomella undulata (1999) Orient. J. Chem, 15, pp. 375-377. Cited 2 times. 7. Dushyent, G., Bohra, A. Toxic effects of various plant part extracts on the causal organism of typhoid fever (2000) Curr. Sci, 78, pp. 780-781. Cited 4 times. 8. Ahmad, F., Alam Khan, R., Rasheed, S. Preliminary screening of methanolic extracts of Celastrus paniculatus and Tecomella undulata for analgesic and antiinflammatory activities (1994) Journal of Ethnopharmacology, 42 (3), pp. 193-198. Cited 12 times. doi: 10.1016/0378-8741(94)90085-X 9. Jain, S.K., Rao, R.R. An assessment of threatened plants of India (1983) Botanical Survey of India, Howrah, p. 334. Page 2 of 5 Scopus - Cur

Analysis of Genetic Diversity of Persea bombycina ‘‘Som’’ Using RAPD-Based Molecular Markers

The utility of RAPD markers in assessing genetic diversity and phenetic relationships in Persea bombycina, a major tree species for golden silk (muga) production, was investigated using 48 genotypes from northeast India. Thirteen RAPD primer combinations generated 93 bands. On average, seven RAPD fragments were amplified per reaction. In a UPGMA phenetic dendrogram based on Jaccard’s coefficient, the P. bombycina accessions showed a high level of genetic variation, as indicated by genetic similarity. The grouping in the phenogram was highly consistent, as indicated by high values of cophenetic correlation and high bootstrap values at the key nodes. The accessions were scattered on a plot derived from principal correspondence analysis. The study concluded that the high level of genetic diversity in the P. bombycina accessions may be attributed to the species’ outcrossing nature. This study may be useful in identifying diverse genetic stocks of P. bombycina, which may then be conserved on a priority basis

A review of data needed to parameterize a dynamic model of measles in developing countries

<p>Abstract</p> <p>Background</p> <p>Dynamic models of infection transmission can project future disease burden within a population. Few dynamic measles models have been developed for low-income countries, where measles disease burden is highest. Our objective was to review the literature on measles epidemiology in low-income countries, with a particular focus on data that are needed to parameterize dynamic models.</p> <p>Methods</p> <p>We included age-stratified case reporting and seroprevalence studies with fair to good sample sizes for mostly urban African and Indian populations. We emphasized studies conducted before widespread immunization. We summarized age-stratified attack rates and seroprevalence profiles across these populations. Using the study data, we fitted a "representative" seroprevalence profile for African and Indian settings. We also used a catalytic model to estimate the age-dependent force of infection for individual African and Indian studies where seroprevalence was surveyed. We used these data to quantify the effects of population density on the basic reproductive number <it>R</it>₀.</p> <p>Results</p> <p>The peak attack rate usually occurred at age 1 year in Africa, and 1 to 2 years in India, which is earlier than in developed countries before mass vaccination. Approximately 60% of children were seropositive for measles antibody by age 2 in Africa and India, according to the representative seroprevalence profiles. A statistically significant decline in the force of infection with age was found in 4 of 6 Indian seroprevalence studies, but not in 2 African studies. This implies that the classic threshold result describing the critical proportion immune (<it>p</it>_c) required to eradicate an infectious disease, <it>p</it>_c= 1-1/<it>R</it>₀, may overestimate the required proportion immune to eradicate measles in some developing country populations. A possible, though not statistically significant, positive relation between population density and <it>R</it>₀for various Indian and African populations was also found. These populations also showed a similar pattern of waning of maternal antibodies. Attack rates in rural Indian populations show little dependence on vaccine coverage or population density compared to urban Indian populations. Estimated <it>R</it>₀values varied widely across populations which has further implications for measles elimination.</p> <p>Conclusions</p> <p>It is possible to develop a broadly informative dynamic model of measles transmission in low-income country settings based on existing literature, though it may be difficult to develop a model that is closely tailored to any given country. Greater efforts to collect data specific to low-income countries would aid in control efforts by allowing highly population-specific models to be developed.</p