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Suresh Kumar Dubey Alpana Singh Takeshi Watanabe Susumu Asakawa Ankit Singla Hironori Arai Kazuyuki Inubushi 《Biology and Fertility of Soils》2014,50(2):369-379
Soil characteristics regulate various belowground microbial processes including methanogenesis and, consequently, affect the structure and function of methanogenic archaeal communities due to change in soil type which in turn influences the CH4 production potential of soils. Thus, five different soil orders (Alfisol, Entisol, Inceptisol, Podzol and Vertisol) were studied to assess their CH4 production potential and also the methanogenic archaeal community structure in dryland irrigated Indian paddy soils. Soil incubation experiments revealed CH4 production to range from 178.4 to 431.2 μg CH4 g-1 dws in all soil orders as: Vertisol<Inceptisol<Entisol<Podzol<Alfisol. The numbers of methanogens as quantified using real-time quantitative polymerase chain reaction (qPCR) targeting mcrA genes varied between 0.06 and 72.97 (×106 copies g-1 dws) and were the highest in Vertisol soil and the least in Alfisol soil. PCR-denaturing gradient gel electrophoresis (DGGE)-based approach targeting 16S rRNA genes revealed diverse methanogenic archaeal communities across all soils. A total of 43 DGGE bands sequenced showed the closely related groups to Methanomicrobiaceae, Methanobacteriaceae, Methanocellales, Methanosarcinaceae, Methanosaetaceae and Crenarchaeota. The composition of methanogenic groups differed among all soils and only the Methanocellales group was common and dominant in all types of soils. The highest diversity of methanogens was found in Inceptisol and Vertisol soils. Methane production potential varied significantly in different soil orders with a positive relationship (p?<?0.05) with methanogens population size, permanganate oxidizable C (POXC) and CO2 production. The present study suggested that CH4 production potential of different soils depends on physicochemical properties, methanogenic archaeal community composition and the population size. 相似文献
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Alpana Kulhari Arun Sheorayan Navneet Saxena Chander Mohan Manisha Mangal Ashok Chaudhury Ashok K. Dhawan Rajwant K. Kalia 《Genetic Resources and Crop Evolution》2013,60(3):1173-1180
The oleo-gum resin of Commiphora wightii (Arn.) Bhandari, a pharmacologically important balsamiferous woody shrub, has been used in treating various ailments and disorders since ancient times (2000 B.C.) due to the presence of steroidal compound guggulsterone. Two bioactive isomers of guggulsterone, E and Z, are responsible for lipid- and cholesterol-lowering and anti-cancerous activities. Further, guggul has been approved as food supplement by US-FDA as well as Council of Europe. Indiscriminate harvest of C. wightii from wild with negligible conservation efforts has lead to its inclusion in IUCN assemblage of endangered plant species. For identification of high guggulsterone yielding ecotypes of C. wightii, using high-performance thin-layer chromatographic (HPTLC) analysis, stem samples were collected from 50 plants from eleven locations in arid tracts of Haryana, Gujarat and Rajasthan. Dried, powdered material was subjected to extraction with petroleum ether using soxhlet apparatus. Samples were spotted on precoated activated silica plates (60F-254) and were developed using toluene–acetone (9:1 v/v) as mobile phase. The analysis was carried out in the absorbance mode at 250 nm using HPTLC scanner. The regression analysis data for the calibration plots for E and Z guggulsterone showed good linear relationship with R2 = 1 and 0.9897, respectively. Highest concentration of guggulsterone E (284 μg/g dry wt) was found in the accession collected from Palana, Bikaner whereas highest guggulsterone Z concentration (89.5 μg/g dry wt) was found in the accession collected from CAZRI, Jodhpur. 相似文献
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Alpana Kulhari Arun Sheorayan Sanjay Kalia Ashok Chaudhury Rajwant K. Kalia 《Genetic Resources and Crop Evolution》2012,59(6):1223-1254
Commiphora wightii (Arn.) Bhandari syn. C. mukul Engl. (Burseraceae) is an economically and pharmacologically important slow growing, dioecious, balsamiferous woody, multipurpose shrub heading towards extinction. Commonly known as “Guggul” due to the presence of steroidal compound guggulsterone in the oleo-gum resin, it has been used in treating various ailments and disorders since ancient times (2000 B.C.). Evaluation and confirmation of hypolipidemic effects of guggul based on Ayurvedic text in 1960s provided a new insight into its pharmacological applications. Two bioactive isomers of guggulsterone, E and Z, are responsible for lipid- and cholesterol-lowering activities. Recently, it has been shown to have anti-cancerous activity also. It is found in the dry regions of Indian subcontinent, namely India, Pakistan and Bangladesh. Ruthless and unscientific harvesting of oleo-gum resin from the wild, by local populations, for economic benefits with negligible conservation efforts has made this species endangered and has led to its inclusion in Red Data Book of IUCN. Although this plant has many excellent traits, adequate attention has not been focused on its conservation and improvement. Conventional propagation methods i.e., seeds, cuttings and air layering are in place but have many limitations. Therefore, application of modern biotechnological tools needs to be standardized for harnessing maximum benefits from this pharmaceutically important plant. An efficient regeneration system needs to be in place for improvement of this genus through genetic transformation and production of useful metabolites in cell cultures. Studies are in progress for micropropagation through shoot multiplication and somatic embryogenesis, as well as for secondary metabolite (guggulsterone) production in callus cultures and bioreactors. No selected germplasm is available for C. wightii since it is a wild plant. Breeding programs have not yet been started due to lack of systematic cultivation and conservation programs. Moreover, little information has been gathered regarding the genetic variability in this species using RAPD and ISSR markers. No details are available about genetic makeup and QTL linkage maps. Investigations are in progress to search sex linked markers in this dioecious species. Research is also in progress to decipher the molecular mechanisms underlying various pharmacological actions of guggul. Since the approval of use of guggul as a food supplement by United States Food and Drug Administration in 1994, an exponential increase in research publications on various aspects of research on guggul have been published. Present communication summarizes the problems, progress made and suggests some future directions of research for this important endangered medicinal plant. 相似文献
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Alpana Anupam Jahangir Imam Syed Mohammad Quatadah Anantha Siddaiah Shankar Prasad Das Mukund Variar Nimai Prasad Mandal 《水稻科学》2017,24(1):10-20
We genotyped 74 rice germplasms including Tripura's local landraces, improved varieties, cultivars and breeding lines and other rice varieties using molecular markers for genetic diversity, drought QTLs, and blast resistance genes. The number of alleles per locus ranged from 2 to 5 with an average of 2.9. The polymorphic information content value per locus ranged from 0.059 (RM537) to 0.755 (RM252) with an average of 0.475. Cluster analysis based on 30 simple sequence repeat markers revealed 5 clusters and also indicated the presence of variability within the rice accessions. The drought QTL qDTY2.1 was found in 56.0% of germplasms and qDTY1.1 was detected in only 6.8% of the germplasms. Out of seven rice blast resistance genes screened, only two rice varieties, RCPL-1-82 and Buh Vubuk (Lubuk), were positive for four blast resistance genes while only Releng possessed two blast resistance genes. Among 74 rice germplasms, only three accessions, Releng, RCPL1-82 and Buh Vubuk (Lubuk), possessed both drought-related QTLs and blast resistance genes. Overall, the 74 indigenous rice genotypes showed low level of genetic diversity, which is in contrast to high level of genetic diversity among rice varieties in northeast India, where highlights the good farming practice, conservation of germplasms and the limitation of molecular markers employed in this study. The presence of both drought related QTLs and blast resistance genes in some of the germplasms can be useful in future breeding programmes. 相似文献
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