Singh H.R.,Tocklai Tea Research Institute |
Singh H.R.,Institutional Biotech Hub |
Deka M.,Gauhati University |
Das S.,Tocklai Tea Research Institute |
Das S.,Institute of Bioresources and Sustainable Development
Functional and Integrative Genomics | Year: 2015
Tea is the second most consumed beverage in the world. A crop loss of up to 43 % has been reported due to blister blight disease of tea caused by a fungus, Exobasidium vexans. Thus, it directly affects the tea industry qualitatively and quantitatively. Solanum tuberosum class I chitinase gene (AF153195) is a plant pathogenesis-related gene. It was introduced into tea genome via Agrobacterium-mediated transformation with hygromycin phosphotransferase (hpt) gene conferring hygromycin resistance as plant selectable marker. A total of 41 hygromycin resistant plantlets were obtained, and PCR analysis established 12 plantlets confirming about the stable integration of transgene in the plant genome. Real-time PCR detected transgene expression in four transgenic plantlets (T28, C57, C9, and T31). Resistance to biotrophic fungal pathogen, E. vexans, was tested by detached leaf infection assay of greenhouse acclimated plantlets. An inhibitory activity against the fungal pathogen was evident from the detached leaves from the transformants compared with the control. Fungal lesion formed on control plantlet whereas the transgenic plantlets showed resistance to inoculated fungal pathogen by the formation of hypersensitivity reaction area. This result suggests that constitutive expression of the potato class I chitinase gene can be exploited to improve resistance to fungal pathogen, E. vexans, in economical perennial plantation crop like tea. © 2015, Springer-Verlag Berlin Heidelberg.
Deb M.,Assam University |
Adhikary P.,Institutional Biotech Hub |
Slama P.,Mendel University in Brno |
Havlicek Z.,Mendel University in Brno |
And 3 more authors.
Acta Universitatis Agriculturae et Silviculturae Mendelianae Brunensis | Year: 2015
Phayre's leaf-monkeys (Trachipithecus phayrei) or Phayre's langurs are old world monkeys that inhabit South-East Asian tropical forests. The species is under a severe threat due to large scale habitat destruction and disturbances by people living near the habitat of langurs. The present study recorded the aggressive behavior of male langurs towards domestic dogs in the Cachar district of Assam. Response of each member in the troop was observed. The sophisticated behavior of males in safeguarding the weaker members was observed. In conclusion, the harassment by domestic dogs may result in the expulsion of Phayre's langurs from their native habitat.
Bhorali P.,Deptt. of Biotechnology |
Bhorali P.,Assam Agricultural University |
Gohain B.,Deptt. of Biotechnology |
Gupta S.,Institutional Biotech Hub |
And 11 more authors.
Indian Journal of Genetics and Plant Breeding | Year: 2012
Fungal diseases are one of the biggest threats for plant growth, development and productivity. Exobasidium vexans is an obligate biotrophic fungal pathogen of tea that causes blister blight, a devastating disease resulting in significant crop losses. A study was carried out to do a comprehensive transcriptome profiling utilizing cDNAAFLP and SSH along with qRT-PCR based expression profiling, with the objective of identification of blister blight inducible defense-related transcripts in tea, particularly in a resistant cultivar. This could potentially be utilized for development of molecular markers associated with resistance blister blight. Candidate transcripts were screened using cDNA-AFLF method, which are differentially expressed between a resistant and a susceptible cultivar under blister blight stress. Further, SSH libraries were constructed for identification of blister blight induced ESTs in the resistant cultivar. In silico analysis, functional annotation and characterization showed that E. vexans challenge rapidly modulates the expression of a large repertoire of genes associated with an array of biochemical processes, particularly defense. A high level of E. vexans-dependent induction was detected for most of the selected genes through qRT-PCRbased expression profiling of selected ESTs. This entire collection of blister blight induced ESTs includes genes involved not only in defense, but in metabolism, energy, transport, protein modification, cell wall fortification, oxidative stress response and signal transduction, which have either direct or indirect implications in conferring plant defense or resistance responses. A number of novel genes were also identified, which need to be investigated further for their probable roles in defense progression. The data provide potential candidates for improving resistance to blister blight either by marker assisted breeding or genetic engineering and sequence information for marker development (SNPs and SSRs), microarray construction, and genome annotation and the information accrued is expected to accelerate molecular characterization of genes of interest.
Malakar C.,Institutional Biotech Hub |
Choudhury P.P.N.,Institutional Biotech Hub |
Choudhury P.P.N.,S S College
Asian Journal of Pharmaceutical and Clinical Research | Year: 2015
It has been noteworthy from the ancient times; the human race is dependent on the use of traditional plant-based medicines as well as polyherbal preparations. And from the last few decades several research works are carried out which confirms the potentiality of these natural sources as a good source of medications. Ipomoea aquatica was among such plant having good nutraceutical applications and is commonly consumed as a vegetable and is commonly found in tropical Asia, India, Africa and Australia, etc. The plant is considered to be a good source of vitamins, minerals, plant proteins, fibers, etc. as well as the plant is supposed to have tremendous pharmacological importance. The present review aims to present a brief overview of the medicinal use as well pharmacological value of the plant. © 2015 Asian Journal of Pharmaceutical and Clinical Research. All rights reserved.
Bhaigyabati T.,Institutional Biotech Hub |
Devi P.G.,Imphal College |
Bag G.C.,Imphal College
Research Journal of Pharmaceutical, Biological and Chemical Sciences | Year: 2014
Hedychium species is one of the important aromatic, ornamental medicinal plants of North east India. In the present study, total flavonoid content and antioxidant activity of aqueous rhizome extract of three Hedychium species namely H. rubrum, H. coronarium and H. spicatum were investigated. In antioxidant activity: free radical scavenging activity, reducing power and total antioxidant activity were determined and expressed in terms of standard used for the respective assay. Total flavonoid content of aqueous rhizome extract of H. rubrum, H. coronarium and H. spicatum in terms of quercetin equivalent (QE) was 3.22, 2.77 and 0.74 μg/100g of extract respectively. In DPPH assay H. rubrum (32.3%) showed the highest free radical scavenging activity followed by H. coronarium (21%) and lowest activity in H. Spicatum (5.76%). In reducing power method, both standard ascorbic acid and sample extracts were found to be increased in a dose dependent manner. Total antioxidant activity of aqueous rhizome extract of H. rubrum, H. coronarium and H. spicatum in terms of ascorbic acid equivalent (AAE) was 207.3, 157.5 and 102.6 μg/ml of extract. The present data indicates that aqueous rhizome extract of all the three Hedychium species are potential source of antioxidant which may be due to the presence of flavonoid in the extracts. Among the three Hedychium species, H. rubrum was found to have the highest total flavonoid content and antioxidant activity.
Kashyap D.,Institutional Biotech Hub |
Sarmah P.,Institutional Biotech Hub |
Sarma A.,Institutional Biotech Hub
Research Journal of Medicinal Plant | Year: 2015
Hibiscus sabdariffa L. (Roselle; Malvaceae) has been used traditionally as food, in herbal drinks, in hot and cold beverages, as flavouring agent in the food industry and as herbal medicine. The calyx of the roselle plant has long been recognised as a source of antioxidants. The objective of this study was to evaluate antioxidant activity, free radical-scavenging and total phenolic content in calyces and epi-calyces of the roselle plant. Methanol extracts showed a positive correlation between phenolic content and antioxidant activity, as with the increase of their phenolic content (134.32±1.82 μg GAE mg-1 for the red variant and 154.60±1.54 μg GAE mg-1 for the white variant), the antioxidant activity of the of the two variants also increases (118.66±0.96 and 102.54±1.08 μg mL-1, respectively). So have the potential to be used as food antioxidants. Moreover, nutritionally both the variants are rich in protein, crude fibre, ascorbic acid. © 2015 Academic Journals Inc.
Sarmah P.,Institutional Biotech Hub |
Dutta S.,Pandu College |
Sarma A.,Institutional Biotech Hub
Agroforestry Systems | Year: 2016
Momordica cochinchinensis Spreng., belonging to family cucurbitaceae, is a large climber generally found under wild growing condition in the Cachar hills region of Assam, India. The fruits of this tuberous plant are supposed to possess high nutritional and medicinal properties and have been widely used in many traditional medicine practices. The present study was carried out to scientifically validate the presence of nutritional property and antioxidant activity of Momordica cochinchinensis found in this part of India. The experimental result reveals that the fruits have a high nutraceutical property and a considerable amount of antioxidative activity as the IC50 value was found to be 294.13 ± 0.46 μg/ml. © 2016 Springer Science+Business Media Dordrecht