Phenolic and flavonoid contents in leaf extracts of Bergenia ligulata have been analysed for the... more Phenolic and flavonoid contents in leaf extracts of Bergenia ligulata have been analysed for their contribution in antimicrobial and antioxidant activities. The extracts were prepared in three solvents (separately) following maceration and soxhelt methods.The antimicrobial activity was tested using disc diffusion assay against a range of microorganisms along with the determination of minimum inhibitory concentration (MIC), while the antioxidant activity was tested following DPPH assay. Leaf extracts exhibited antimicrobial activity against all the three groups of microorganisms; results coincided with respective MIC. In general, the methanol extracts prepared through maceration favoured the determination of antimicrobial and antioxidant activities. Maximum values for phenolic and flavonoid contents were obtained in macerated methanol and ethyl acetate extracts, respectively. The statistical correlations exhibited the extent of the contribution of phenolic and flavonoid contents in antimicrobial and antioxidant activities and also indicated the involvement of other plant metabolites.
The present paper deals with the rhizosphere effect exerted on the microbial communities by ten r... more The present paper deals with the rhizosphere effect exerted on the microbial communities by ten representative and important tree species of the Indian Himalayan region. The study covered a wide altitudinal range (1200 to 3610 m above mean sea level) representing subtropical to subalpine climatic conditions. The rhizosphere to soil (R:S) ratio was found to range from 0.2 to 3.5, 0.3 to 2.9, and 0.3 to 3.4, for bacteria, actinomycetes and fungi, respectively. Barring a few exceptions, generally the tree species of subtropical and temperate regions exerted a slight stimulatory effect on the rhizosphere microorganisms. Coniferous species of the subtropical and temperate locations viz., Cedrus, Pinus and Taxus supported relatively higher microbial population in the rhizosphere in comparison to other species. Abies pindrow (a conifer), Betula utilis, and Rhododendron campanulatum, species of the subalpine region were found to exert a distinct negative rhizosphere effect. The negative rhizosphere effect coincided with lowering of the soil pH in the rhizosphere region.
Field-based experiments were conducted to evaluate the promotion abilities of Bacillus subtilis N... more Field-based experiments were conducted to evaluate the promotion abilities of Bacillus subtilis NRRL B-30408 for growth of lentil (Lens esculenta Moench) at a mountain location of Indian Himalaya in two consecutive years. Observations were recorded for plant growth, yield, nodulation, root colonization by arbuscular mycorrhizal and endophytic fungi, and other related parameters. A positive influence of bacterial inoculation on plant biomass and yield-related parameters was recorded in both years. The significant increase in growth and nodule numbers as well as leghaemoglobin and protein concentrations of nodules indicated an enhancement in efficiency of the Rhizobium-legume symbiosis due to bacterial inoculation. An increase in protein concentration was also recorded for shoots, leaves, and seeds. Due to bacterial inoculation, there was an increase in colonization by endophytic fungi and a simultaneous decrease in colonization by arbuscular mycorrhizal fungi in roots. Based on the results of this field study, inoculation with suitable plant growth-promoting rhizobacteria instead of dual inoculation is suggested as a better option for improving the yield and related attributes of a primary dietary legume such as lentil.
A psychrotolerant phosphate solubilizing fungus has been isolated from the rock soil of a cold de... more A psychrotolerant phosphate solubilizing fungus has been isolated from the rock soil of a cold desert site in Indian Himalaya. The fungus grows from 4 to 35°C (optimum 21°C), and from 2 to 13.5 pH (optimum 9) under laboratory conditions. Based on phenotypic characters and 26S rDNA analysis, the fungus is identified as Paecilomyces hepiali. In quantitative estimation that was carried out at 9, 14, and 21°C, the fungus solubilized maximum phosphate at 14°C. In view of the slow growth and persistence of the desired activity at low temperature, the estimation was carried out for a longer period, i.e., up to 6 weeks. The suboptimal conditions for growth and biomass production were found to be optimal for phosphate solubilization by the fungus. At 14 and 9°C, the solubilization touched its maximum on day 42. Decline in pH was found to be significantly correlated with the phosphate solubilization at all the temperatures, under consideration. The acid phosphatase activity was found to be more prominent than alkaline phosphatase in culture filtrate. High performance thin layer chromatography (HPTLC) analysis showed production of six organic acids, gluconic and a-keto glutaric acid being in maximum amount in the culture filtrate. The study has ecological significance in view of the nutrient cycling under low temperature environment, prevalent in Himalayan region.
Three species of Aspergillus, namely, A. niger, A. glaucus and A. sydowii, isolated from soil sam... more Three species of Aspergillus, namely, A. niger, A. glaucus and A. sydowii, isolated from soil samples collected from the Indian Himalayan Region (IHR), have been investigated for solubilization of aluminium phosphate and iron phosphate in the presence of different carbon and nitrogen sources. Preference of each fungal species varied for nitrogen and carbon sources, in terms of phosphate-solubilization. Among three species, Aspergillus niger gave the best results; it solubilized 32% and 8% of the supplemented aluminium phosphate and iron phosphate, respectively. The results indicated that the effect of carbon and nitrogen sources can influence the phosphate solubilizing efficiency of all the three Aspergillus spp. tested. All the three species were found to be plant-growth promoters in bioassays conducted under greenhouse conditions. The Al and Fe phosphate solubilization efficiency, investigated in the present study, is at the lower end of their previously reported tricalcium phosphate solubilization efficiency. The cultures are likely to have better field applications in agrobiotechnology, due to their potential towards solubilization of Al and Fe phosphates, which are known to have lower solubility through microbial activity.
On-farm inoculation trials have been conducted to evaluate the potential of Bacillus subtilis NRR... more On-farm inoculation trials have been conducted to evaluate the potential of Bacillus subtilis NRRL B-30408 in respect of plant growth promotion, for two consecutive years, under rainfed conditions at a mountain location in the Indian Himalayan Region (IHR). For this, one cereal (Oryza sativa) and two millets (Eleusine coracana and Echinochloa frumentacea), were used as test crops. Observations were recorded in terms of plant growth, yield, chlorophyll content, and root colonization by various groups of microorganisms. Positive influence of bacterial inoculation on all the three crops, statistically significant in case of most parameters examined as compared to untreated controls, was recorded in both the years. There was a significant increase in chlorophyll concentration in leaves of inoculated plants. While the bacterial inoculation stimulated the free living bacterial and actinomycetes populations in the rhizosphere, the fungal population was somewhat suppressed; indicative of the antifungal property of the inoculant. The treatment also enhanced the colonization of arbuscular mycorrhizae (AM), and the endophytes associated with the roots. In conclusion, the plant growth promotion, recorded as a result of microbial inoculation, is attributed to the microbial shift in the native microflora of the rhizosphere. Based on the results of this field study, B. subtilis NRRL B-30408 can be proposed as an efficient bioinoculant for the hill crops, grown under rainfed conditions of the mountain ecosystem. The main aim of this study was on farm demonstration of the microbe based technology with peoples' participation, with a view of adoption of the technology by the farmers.
is for personal use only and shall not be selfarchived in electronic repositories. If you wish to... more is for personal use only and shall not be selfarchived in electronic repositories. If you wish to self-archive your work, please use the accepted author's version for posting to your own website or your institution's repository.
Dendrocalamus strictus ((Roxb.) Nees) was tested as a perennial host plant for propagation of an ... more Dendrocalamus strictus ((Roxb.) Nees) was tested as a perennial host plant for propagation of an arbuscular mycorrhizal (AM) fungal consortium, initially isolated from rhizosphere of tea plants growing in the colder regions. The host performance in terms of colonization and spore production was compared with two annual hosts. The mycorrhizal dependency and growth enhancement potential were analyzed to test the suitability of D. strictus as a host plant. After 90 days of growth, 77.2% roots of D. strictus were found to be colonized by AM fungi with a spore count of 7 per g soil. AM fungal colonization and spore density values were lower in case of the host plants tested. Growth of D. strictus plants was found to be enhanced, in terms of all studied parameters; significant increases were recorded in shoot length as well as fresh and dry weight of shoots, a part of commercial importance. Similarly, P content, protein concentration, chlorophyll a and chlorophyll b contents were found to increase significantly. These data suggest that D. strictus can be used for the multiplication of AM fungi, isolated originally from the rhizosphere of tea; simultaneously, higher shoot biomass can provide additional economic benefit, using this environment friendly technology.
Soil samples, collected after the fire operations at agricultural sites under shifting cultivatio... more Soil samples, collected after the fire operations at agricultural sites under shifting cultivation in northeast India, were subjected to physico-chemical and microbial analysis. The fire affected various physico-chemical properties of the soil. Significant differences in pH and electrical conductivity were recorded in soil of fired and fallow plots. Significantly higher amounts of total organic carbon and nitrogen were estimated in fallow plots as compared to the fired. Difference in total phosphates was not significant. The fire operations resulted in stimulation of microbial communities. The bacteria were the most affected group followed by actinomycetes and fungi, respectively. The bacterial and actinomycetes counts were significantly higher in fired plots as compared to the fallow plots. The representative bacterial species recovered from the 'fired plots' belonged to the genus Bacillus and Pseudomonas. 16S rRNA analysis revealed their maximum similarity with B. clausii, B. licheniformis, B. megaterium, B. subtilis, B. thuringiensis, P. aeruginosa and P. stutzeri. Most of these species were found to be positive for phosphate solubilization and antagonism in plate based assays. In view of the importance of Bacillus and Pseudomonas species in plant growth promotion and biocontrol, recovery of these species after fire operations is indicative of the microbiological merit of shifting cultivation.
Your article is protected by copyright and all rights are held exclusively by Springer-Verlag and... more Your article is protected by copyright and all rights are held exclusively by Springer-Verlag and the University of Milan. This e-offprint is for personal use only and shall not be selfarchived in electronic repositories. If you wish to self-archive your article, please use the accepted manuscript version for posting on your own website. You may further deposit the accepted manuscript version in any repository, provided it is only made publicly available 12 months after official publication or later and provided acknowledgement is given to the original source of publication and a link is inserted to the published article on Springer's website. The link must be accompanied by the following text: "The final publication is available at link.springer.com".
A long term study has been carried out for over a decade across various tea gardens, located in d... more A long term study has been carried out for over a decade across various tea gardens, located in different parts of Indian Himalayan Region (IHR), with a focus on rhizosphere microbiology of tea. Occurrence of 'negative rhizosphere effect' exerted by the established tea bushes, in contrast to the normal stimulatory effect exhibited by the plants in general as well as young tea bushes, is the first and foremost feature associated with tea plants. Colonization by large populations of antagonists and lowering of the soil pH are the other important characteristics associated with tea rhizosphere. With a view of scaling down the use of chemical fertilizers, experiments were conducted on isolation, characterization and formulation of suitable microbial inoculants for use in tea plantations across hilly regions. Based on a number of attributes related to plant growth promotion and disease control, selected bacterial and mycorrhizal species have been developed in suitable formulations for application in tea plantations. The post-application observations indicated the benefits of microbial inoculations on seed, cutting and tissue culture raised tea plants. The present paper is an attempt to review the basic and applied research work carried out on rhizosphere microbiology of tea, particularly in the last two decades, with reference to possible application in the tea industry.
Laccase production by a temperature and pH tolerant fungal strain (GBPI-CDF-03) isolated from a g... more Laccase production by a temperature and pH tolerant fungal strain (GBPI-CDF-03) isolated from a glacial site in Indian Himalayan Region (IHR) has been investigated. The fungus developed white cottony mass on potato dextrose agar and revealed threadlike mycelium under microscope. ITS region analysis of fungus showed its 100% similarity with Trametes hirsuta. The fungus tolerated temperature from 4 to 48 ∘ C ± 2 (25 ∘ C opt.) and pH 3-13 (5-7 opt.). Molecular weight of laccase was determined approximately 45 kDa by native PAGE. Amplification of laccase gene fragment (corresponding to the copper-binding conserved domain) contained 200 bp. The optimum pH for laccase production, at optimum growth temperature, was determined between 5.5 and 7.5. In optimization experiments, fructose and ammonium sulfate were found to be the best carbon and nitrogen sources, respectively, for enhancing the laccase production. Production of laccase was favored by high carbon/nitrogen ratio. Addition of CuSO 4 (up to 1.0 mM) induced laccase production up to 2-fold, in case of 0.4 mM concentration. Addition of organic solvents also induced the production of laccase; acetone showed the highest (2-fold) induction. The study has implications in bioprospecting of ecologically resilient microbial strains.
Your article is protected by copyright and all rights are held exclusively by The National Academ... more Your article is protected by copyright and all rights are held exclusively by The National Academy of Sciences, India. This e-offprint is for personal use only and shall not be selfarchived in electronic repositories. If you wish to self-archive your article, please use the accepted manuscript version for posting on your own website. You may further deposit the accepted manuscript version in any repository, provided it is only made publicly available 12 months after official publication or later and provided acknowledgement is given to the original source of publication and a link is inserted to the published article on Springer's website. The link must be accompanied by the following text: "The final publication is available at link.springer.com".
Mana village (Chamoli district, Uttarakhand, India), situated in high altitudes (3,238 m above me... more Mana village (Chamoli district, Uttarakhand, India), situated in high altitudes (3,238 m above mean sea level) of Indian Himalayan region, represents cold desert climatic conditions. At Mana, potato is grown from May to September, while the site remains snow clad for approximately six months (from October to April). Soil samples, collected from Mana potato fields, were analyzed for cultivable microbial diversity along with the chemical and enzymatic properties. The analysis revealed colonization of soil by microflora in moderate numbers (up to 10 7 CFU/g soil) with limited species level. 25 morphologically distinct microbial isolates belonging to Gram +ve and Gram −ve bacteria, actinomycetes, and fungi including yeast were isolated. The bacteria were tentatively identified as species of Bacillus and Pseudomonas, while the majority of the fungal isolates belonged to the species of Penicillium. These microbial isolates possessed plant growth promotion and biocontrol properties assessed mainly in terms of production of indole acetic acid and hydrolytic enzymes and phosphate solubilization. The soil, when used as "inoculum" in plant based bioassays, exhibited positive influence on plant growth related parameters. The limited diversity of cold tolerant microbial species also extends opportunity to understand the resilience possessed by these organisms under low temperature environment.
Phenolics Antioxidants Indian Himalayan Region (IHR) a b s t r a c t Aims: To determine the influ... more Phenolics Antioxidants Indian Himalayan Region (IHR) a b s t r a c t Aims: To determine the influence of location, seasonal variation and solvent system in production of phytochemicals and antioxidants from ginkgo leaves.
Phenolic and flavonoid contents in leaf extracts of Bergenia ligulata have been analysed for the... more Phenolic and flavonoid contents in leaf extracts of Bergenia ligulata have been analysed for their contribution in antimicrobial and antioxidant activities. The extracts were prepared in three solvents (separately) following maceration and soxhelt methods.The antimicrobial activity was tested using disc diffusion assay against a range of microorganisms along with the determination of minimum inhibitory concentration (MIC), while the antioxidant activity was tested following DPPH assay. Leaf extracts exhibited antimicrobial activity against all the three groups of microorganisms; results coincided with respective MIC. In general, the methanol extracts prepared through maceration favoured the determination of antimicrobial and antioxidant activities. Maximum values for phenolic and flavonoid contents were obtained in macerated methanol and ethyl acetate extracts, respectively. The statistical correlations exhibited the extent of the contribution of phenolic and flavonoid contents in antimicrobial and antioxidant activities and also indicated the involvement of other plant metabolites.
The present paper deals with the rhizosphere effect exerted on the microbial communities by ten r... more The present paper deals with the rhizosphere effect exerted on the microbial communities by ten representative and important tree species of the Indian Himalayan region. The study covered a wide altitudinal range (1200 to 3610 m above mean sea level) representing subtropical to subalpine climatic conditions. The rhizosphere to soil (R:S) ratio was found to range from 0.2 to 3.5, 0.3 to 2.9, and 0.3 to 3.4, for bacteria, actinomycetes and fungi, respectively. Barring a few exceptions, generally the tree species of subtropical and temperate regions exerted a slight stimulatory effect on the rhizosphere microorganisms. Coniferous species of the subtropical and temperate locations viz., Cedrus, Pinus and Taxus supported relatively higher microbial population in the rhizosphere in comparison to other species. Abies pindrow (a conifer), Betula utilis, and Rhododendron campanulatum, species of the subalpine region were found to exert a distinct negative rhizosphere effect. The negative rhizosphere effect coincided with lowering of the soil pH in the rhizosphere region.
Field-based experiments were conducted to evaluate the promotion abilities of Bacillus subtilis N... more Field-based experiments were conducted to evaluate the promotion abilities of Bacillus subtilis NRRL B-30408 for growth of lentil (Lens esculenta Moench) at a mountain location of Indian Himalaya in two consecutive years. Observations were recorded for plant growth, yield, nodulation, root colonization by arbuscular mycorrhizal and endophytic fungi, and other related parameters. A positive influence of bacterial inoculation on plant biomass and yield-related parameters was recorded in both years. The significant increase in growth and nodule numbers as well as leghaemoglobin and protein concentrations of nodules indicated an enhancement in efficiency of the Rhizobium-legume symbiosis due to bacterial inoculation. An increase in protein concentration was also recorded for shoots, leaves, and seeds. Due to bacterial inoculation, there was an increase in colonization by endophytic fungi and a simultaneous decrease in colonization by arbuscular mycorrhizal fungi in roots. Based on the results of this field study, inoculation with suitable plant growth-promoting rhizobacteria instead of dual inoculation is suggested as a better option for improving the yield and related attributes of a primary dietary legume such as lentil.
A psychrotolerant phosphate solubilizing fungus has been isolated from the rock soil of a cold de... more A psychrotolerant phosphate solubilizing fungus has been isolated from the rock soil of a cold desert site in Indian Himalaya. The fungus grows from 4 to 35°C (optimum 21°C), and from 2 to 13.5 pH (optimum 9) under laboratory conditions. Based on phenotypic characters and 26S rDNA analysis, the fungus is identified as Paecilomyces hepiali. In quantitative estimation that was carried out at 9, 14, and 21°C, the fungus solubilized maximum phosphate at 14°C. In view of the slow growth and persistence of the desired activity at low temperature, the estimation was carried out for a longer period, i.e., up to 6 weeks. The suboptimal conditions for growth and biomass production were found to be optimal for phosphate solubilization by the fungus. At 14 and 9°C, the solubilization touched its maximum on day 42. Decline in pH was found to be significantly correlated with the phosphate solubilization at all the temperatures, under consideration. The acid phosphatase activity was found to be more prominent than alkaline phosphatase in culture filtrate. High performance thin layer chromatography (HPTLC) analysis showed production of six organic acids, gluconic and a-keto glutaric acid being in maximum amount in the culture filtrate. The study has ecological significance in view of the nutrient cycling under low temperature environment, prevalent in Himalayan region.
Three species of Aspergillus, namely, A. niger, A. glaucus and A. sydowii, isolated from soil sam... more Three species of Aspergillus, namely, A. niger, A. glaucus and A. sydowii, isolated from soil samples collected from the Indian Himalayan Region (IHR), have been investigated for solubilization of aluminium phosphate and iron phosphate in the presence of different carbon and nitrogen sources. Preference of each fungal species varied for nitrogen and carbon sources, in terms of phosphate-solubilization. Among three species, Aspergillus niger gave the best results; it solubilized 32% and 8% of the supplemented aluminium phosphate and iron phosphate, respectively. The results indicated that the effect of carbon and nitrogen sources can influence the phosphate solubilizing efficiency of all the three Aspergillus spp. tested. All the three species were found to be plant-growth promoters in bioassays conducted under greenhouse conditions. The Al and Fe phosphate solubilization efficiency, investigated in the present study, is at the lower end of their previously reported tricalcium phosphate solubilization efficiency. The cultures are likely to have better field applications in agrobiotechnology, due to their potential towards solubilization of Al and Fe phosphates, which are known to have lower solubility through microbial activity.
On-farm inoculation trials have been conducted to evaluate the potential of Bacillus subtilis NRR... more On-farm inoculation trials have been conducted to evaluate the potential of Bacillus subtilis NRRL B-30408 in respect of plant growth promotion, for two consecutive years, under rainfed conditions at a mountain location in the Indian Himalayan Region (IHR). For this, one cereal (Oryza sativa) and two millets (Eleusine coracana and Echinochloa frumentacea), were used as test crops. Observations were recorded in terms of plant growth, yield, chlorophyll content, and root colonization by various groups of microorganisms. Positive influence of bacterial inoculation on all the three crops, statistically significant in case of most parameters examined as compared to untreated controls, was recorded in both the years. There was a significant increase in chlorophyll concentration in leaves of inoculated plants. While the bacterial inoculation stimulated the free living bacterial and actinomycetes populations in the rhizosphere, the fungal population was somewhat suppressed; indicative of the antifungal property of the inoculant. The treatment also enhanced the colonization of arbuscular mycorrhizae (AM), and the endophytes associated with the roots. In conclusion, the plant growth promotion, recorded as a result of microbial inoculation, is attributed to the microbial shift in the native microflora of the rhizosphere. Based on the results of this field study, B. subtilis NRRL B-30408 can be proposed as an efficient bioinoculant for the hill crops, grown under rainfed conditions of the mountain ecosystem. The main aim of this study was on farm demonstration of the microbe based technology with peoples' participation, with a view of adoption of the technology by the farmers.
is for personal use only and shall not be selfarchived in electronic repositories. If you wish to... more is for personal use only and shall not be selfarchived in electronic repositories. If you wish to self-archive your work, please use the accepted author's version for posting to your own website or your institution's repository.
Dendrocalamus strictus ((Roxb.) Nees) was tested as a perennial host plant for propagation of an ... more Dendrocalamus strictus ((Roxb.) Nees) was tested as a perennial host plant for propagation of an arbuscular mycorrhizal (AM) fungal consortium, initially isolated from rhizosphere of tea plants growing in the colder regions. The host performance in terms of colonization and spore production was compared with two annual hosts. The mycorrhizal dependency and growth enhancement potential were analyzed to test the suitability of D. strictus as a host plant. After 90 days of growth, 77.2% roots of D. strictus were found to be colonized by AM fungi with a spore count of 7 per g soil. AM fungal colonization and spore density values were lower in case of the host plants tested. Growth of D. strictus plants was found to be enhanced, in terms of all studied parameters; significant increases were recorded in shoot length as well as fresh and dry weight of shoots, a part of commercial importance. Similarly, P content, protein concentration, chlorophyll a and chlorophyll b contents were found to increase significantly. These data suggest that D. strictus can be used for the multiplication of AM fungi, isolated originally from the rhizosphere of tea; simultaneously, higher shoot biomass can provide additional economic benefit, using this environment friendly technology.
Soil samples, collected after the fire operations at agricultural sites under shifting cultivatio... more Soil samples, collected after the fire operations at agricultural sites under shifting cultivation in northeast India, were subjected to physico-chemical and microbial analysis. The fire affected various physico-chemical properties of the soil. Significant differences in pH and electrical conductivity were recorded in soil of fired and fallow plots. Significantly higher amounts of total organic carbon and nitrogen were estimated in fallow plots as compared to the fired. Difference in total phosphates was not significant. The fire operations resulted in stimulation of microbial communities. The bacteria were the most affected group followed by actinomycetes and fungi, respectively. The bacterial and actinomycetes counts were significantly higher in fired plots as compared to the fallow plots. The representative bacterial species recovered from the 'fired plots' belonged to the genus Bacillus and Pseudomonas. 16S rRNA analysis revealed their maximum similarity with B. clausii, B. licheniformis, B. megaterium, B. subtilis, B. thuringiensis, P. aeruginosa and P. stutzeri. Most of these species were found to be positive for phosphate solubilization and antagonism in plate based assays. In view of the importance of Bacillus and Pseudomonas species in plant growth promotion and biocontrol, recovery of these species after fire operations is indicative of the microbiological merit of shifting cultivation.
Your article is protected by copyright and all rights are held exclusively by Springer-Verlag and... more Your article is protected by copyright and all rights are held exclusively by Springer-Verlag and the University of Milan. This e-offprint is for personal use only and shall not be selfarchived in electronic repositories. If you wish to self-archive your article, please use the accepted manuscript version for posting on your own website. You may further deposit the accepted manuscript version in any repository, provided it is only made publicly available 12 months after official publication or later and provided acknowledgement is given to the original source of publication and a link is inserted to the published article on Springer's website. The link must be accompanied by the following text: "The final publication is available at link.springer.com".
A long term study has been carried out for over a decade across various tea gardens, located in d... more A long term study has been carried out for over a decade across various tea gardens, located in different parts of Indian Himalayan Region (IHR), with a focus on rhizosphere microbiology of tea. Occurrence of 'negative rhizosphere effect' exerted by the established tea bushes, in contrast to the normal stimulatory effect exhibited by the plants in general as well as young tea bushes, is the first and foremost feature associated with tea plants. Colonization by large populations of antagonists and lowering of the soil pH are the other important characteristics associated with tea rhizosphere. With a view of scaling down the use of chemical fertilizers, experiments were conducted on isolation, characterization and formulation of suitable microbial inoculants for use in tea plantations across hilly regions. Based on a number of attributes related to plant growth promotion and disease control, selected bacterial and mycorrhizal species have been developed in suitable formulations for application in tea plantations. The post-application observations indicated the benefits of microbial inoculations on seed, cutting and tissue culture raised tea plants. The present paper is an attempt to review the basic and applied research work carried out on rhizosphere microbiology of tea, particularly in the last two decades, with reference to possible application in the tea industry.
Laccase production by a temperature and pH tolerant fungal strain (GBPI-CDF-03) isolated from a g... more Laccase production by a temperature and pH tolerant fungal strain (GBPI-CDF-03) isolated from a glacial site in Indian Himalayan Region (IHR) has been investigated. The fungus developed white cottony mass on potato dextrose agar and revealed threadlike mycelium under microscope. ITS region analysis of fungus showed its 100% similarity with Trametes hirsuta. The fungus tolerated temperature from 4 to 48 ∘ C ± 2 (25 ∘ C opt.) and pH 3-13 (5-7 opt.). Molecular weight of laccase was determined approximately 45 kDa by native PAGE. Amplification of laccase gene fragment (corresponding to the copper-binding conserved domain) contained 200 bp. The optimum pH for laccase production, at optimum growth temperature, was determined between 5.5 and 7.5. In optimization experiments, fructose and ammonium sulfate were found to be the best carbon and nitrogen sources, respectively, for enhancing the laccase production. Production of laccase was favored by high carbon/nitrogen ratio. Addition of CuSO 4 (up to 1.0 mM) induced laccase production up to 2-fold, in case of 0.4 mM concentration. Addition of organic solvents also induced the production of laccase; acetone showed the highest (2-fold) induction. The study has implications in bioprospecting of ecologically resilient microbial strains.
Your article is protected by copyright and all rights are held exclusively by The National Academ... more Your article is protected by copyright and all rights are held exclusively by The National Academy of Sciences, India. This e-offprint is for personal use only and shall not be selfarchived in electronic repositories. If you wish to self-archive your article, please use the accepted manuscript version for posting on your own website. You may further deposit the accepted manuscript version in any repository, provided it is only made publicly available 12 months after official publication or later and provided acknowledgement is given to the original source of publication and a link is inserted to the published article on Springer's website. The link must be accompanied by the following text: "The final publication is available at link.springer.com".
Mana village (Chamoli district, Uttarakhand, India), situated in high altitudes (3,238 m above me... more Mana village (Chamoli district, Uttarakhand, India), situated in high altitudes (3,238 m above mean sea level) of Indian Himalayan region, represents cold desert climatic conditions. At Mana, potato is grown from May to September, while the site remains snow clad for approximately six months (from October to April). Soil samples, collected from Mana potato fields, were analyzed for cultivable microbial diversity along with the chemical and enzymatic properties. The analysis revealed colonization of soil by microflora in moderate numbers (up to 10 7 CFU/g soil) with limited species level. 25 morphologically distinct microbial isolates belonging to Gram +ve and Gram −ve bacteria, actinomycetes, and fungi including yeast were isolated. The bacteria were tentatively identified as species of Bacillus and Pseudomonas, while the majority of the fungal isolates belonged to the species of Penicillium. These microbial isolates possessed plant growth promotion and biocontrol properties assessed mainly in terms of production of indole acetic acid and hydrolytic enzymes and phosphate solubilization. The soil, when used as "inoculum" in plant based bioassays, exhibited positive influence on plant growth related parameters. The limited diversity of cold tolerant microbial species also extends opportunity to understand the resilience possessed by these organisms under low temperature environment.
Phenolics Antioxidants Indian Himalayan Region (IHR) a b s t r a c t Aims: To determine the influ... more Phenolics Antioxidants Indian Himalayan Region (IHR) a b s t r a c t Aims: To determine the influence of location, seasonal variation and solvent system in production of phytochemicals and antioxidants from ginkgo leaves.
Uploads
Papers by Anita Pandey
were prepared in three solvents (separately) following maceration and soxhelt methods.The antimicrobial activity was tested using disc diffusion assay against a range of
microorganisms along with the determination of minimum inhibitory concentration (MIC), while the antioxidant activity was tested following DPPH assay. Leaf extracts exhibited antimicrobial activity against all the three groups of microorganisms; results coincided with respective MIC. In general, the methanol extracts prepared through
maceration favoured the determination of antimicrobial and antioxidant activities. Maximum values for phenolic and flavonoid contents were obtained in macerated
methanol and ethyl acetate extracts, respectively. The statistical correlations exhibited the extent of the contribution of phenolic and flavonoid contents in antimicrobial and
antioxidant activities and also indicated the involvement of other plant metabolites.
were prepared in three solvents (separately) following maceration and soxhelt methods.The antimicrobial activity was tested using disc diffusion assay against a range of
microorganisms along with the determination of minimum inhibitory concentration (MIC), while the antioxidant activity was tested following DPPH assay. Leaf extracts exhibited antimicrobial activity against all the three groups of microorganisms; results coincided with respective MIC. In general, the methanol extracts prepared through
maceration favoured the determination of antimicrobial and antioxidant activities. Maximum values for phenolic and flavonoid contents were obtained in macerated
methanol and ethyl acetate extracts, respectively. The statistical correlations exhibited the extent of the contribution of phenolic and flavonoid contents in antimicrobial and
antioxidant activities and also indicated the involvement of other plant metabolites.