UPASI Tea Research Foundation

Valparai, India

UPASI Tea Research Foundation

Valparai, India

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Prabu G.R.,UPASI Tea Research Foundation | Prabu G.R.,Karpagam University | Mandal A.K.A.,UPASI Tea Research Foundation | Mandal A.K.A.,Vellore Institute of Technology
Genomics, Proteomics and Bioinformatics | Year: 2010

MicroRNAs (miRNAs) are a newly identified class of small non-protein-coding post-transcriptional regulatory RNA in both plants and animals. The use of computational homology based search for expressed sequence tags (ESTs) with the Ambros empirical formula and other structural feature criteria filter is a suitable combination towards the discovery and isolation of conserved miRNAs from tea and other plant species whose genomes are not yet sequenced. In the present study, we blasted the database of tea (Camellia sinensis) ESTs to search for potential miRNAs, using previously known plant miRNAs. For the first time, four candidate miRNAs from four families were identified in tea. Using the newly identified miRNA sequences, a total of 30 potential target genes were identified for 11 miRNA families; 6 of these predicted target genes encode transcription factors (20%), 16 target genes appear to play roles in diverse physiological processes (53%) and 8 target genes have hypothetical or unknown functions (27%). These findings considerably broaden the scope of understanding the functions of miRNA in tea. © 2010 Beijing Genomics Institute.

Prabu G.R.,UPASI Tea Research Foundation | Prabu G.R.,Karpagam University | Thirugnanasambantham K.,UPASI Tea Research Foundation | Mandal A.K.A.,UPASI Tea Research Foundation | And 2 more authors.
Biologia Plantarum | Year: 2012

Nucleoside diphosphate kinase (NDPK) operates in the homeostasis of cellular nucleoside triphosphate (NTP) pools and the cytosolic NDPK1 is the main NDPK isoform in plants, accounting for more than 70 % of total NDPK activity in plant. A full length cDNA (697 bp), designated as CsNDPK1 was cloned from Camellia sinensis (L.) O. Kuntze leaves. Sequence analysis of CsNDPK1 shows several motifs, binding and catalytic sites which are highly conserved among other NDPKs. Southern blot analysis revealed that tea genome has two copies of CsNDPK1. Transcription pattern analysis indicated that CsNDPK1 is expressed in all tissues examined, but expressed more in buds than in other organs. © 2012 Springer Science+Business Media B.V.

Thirugnanasambantham K.,UPASI Tea Research Foundation | Prabu G.,UPASI Tea Research Foundation | Prabu G.,Karpagam University | Palanisamy S.,UPASI Tea Research Foundation | And 3 more authors.
Applied Biochemistry and Biotechnology | Year: 2013

Abstract Bud dormancy is of ecological and economical interest due to its impact on tea (Camellia sinensis (L.) O. Kuntze) plant growth and yield. Growth regulation associated with dormancy is an essential element in plant's life cycle that leads to changes in expression of large number of genes. In order to identify and provide a picture of the transcriptome profile, cDNA library was constructed from dormant bud (banjhi) of tea. Sequence and gene ontology analysis of 3,500 clones, in many cases, enabled their functional categorization concerning the bud growth. Based on the cDNA library data, the putative role of identified genes from tea is discussed in relation to growth and dormancy, which includes morphogenesis, cellular differentiation, tropism, cell cycle, signaling, and various metabolic pathways. There was a higher representation of unknown processes such as unknown molecular functions (65.80 %), unknown biological processes (62.46 %), and unknown cellular components (67.42 %). However, these unknown transcripts represented a novel component of transcripts in tea plant bud growth and/or dormancy development. The identified transcripts and expressed sequence tags provides a valuable public resource and preliminary insights into the molecular mechanisms of bud dormancy regulation. Further, the findings will be the target of future expression experiments, particularly for further identification of dormancy-related genes in this species. © Springer Science+Business Media New York 2013.

Krishnaraj T.,UPASI Tea Research Foundation | Gajjeraman P.,UPASI Tea Research Foundation | Gajjeraman P.,Karpagam University | Palanisamy S.,UPASI Tea Research Foundation | And 3 more authors.
Plant Physiology and Biochemistry | Year: 2011

Growth regulation associated with dormancy is an essential element in plant's life cycle that leads to changes in expression of large number of genes. Forward and reverse suppression subtractive hybridization (SSH) libraries were developed to identify and characterize the genes associated with bud (banjhi) dormancy in tea (Camellia sinensis (L.) O. Kuntze). Efficiency of subtraction was confirmed by comparing the abundance of β-actin gene. A total of 17 and 45 unique sequences were obtained from forward and reverse SSH library respectively. Many of the differentially regulated genes have unknown (41.1% and 26.7%) or hypothetical functions (11.7% and 2.2%) in forward and reverse SSH library respectively, while others have a role in cell growth and metabolism. Further, semi-quantitative RT-PCR was carried out for selected genes to validate the quality of ESTs from SSH library. Gene Ontology analysis identified a greater association of these ESTs in cellular metabolic pathways and their relevance to bud dormancy. Based on the EST data, the putative role of identified genes from tea is discussed in relation to dormancy, which includes various metabolic and signalling pathways. We demonstrated that SSH is an efficient tool for enriching up- and down-regulated genes related to bud dormancy in tea. This study represents an attempt to investigate banjhi dormancy in tea under field conditions, and the findings indicate that there is a potential to develop new approaches to modulate dormancy in this species. © 2011 Elsevier Masson SAS.

Vasanthakumar D.,UPASI Tea Research Foundation Tea Research Institute | Babu A.,Tea Research Association | Shanmugapriyan R.,UPASI Tea Research Foundation | Subramaniam S.R.,UPASI Tea Research Foundation Tea Research Institute
International Journal of Acarology | Year: 2013

Azter (azadirachtin 0.15% EC), a neem-based pesticide, was evaluated for acaricidal activity against the red spider mite (RSM) Oligonychus coffeae at three different concentrations (1125, 2250 and 3375 mL/ha) under laboratory and field conditions. All the tested concentrations caused 100% mortality under laboratory conditions. When RSMs were provided with Azter-treated leaves for egg-laying, the numbers of eggs laid were significantly lower than that on untreated control leaves. Application of Azter did not affect the non-target organisms such as Mallada desjardinsi and Oligota pygmaea (natural enemies of RSM). Based on the results obtained from the laboratory studies, a field study was conducted to confirm the acaricidal effect of Azter and the results revealed the potential utility of this neem-based biopesticide as safer for natural enemies in an integrated pest management programme against RSM to minimize the pesticide load in the tea ecosystem. © 2013 Copyright Taylor and Francis Group, LLC.

Kottur G.,UPASI Tea Research Foundation | Venkatesan S.,Cavinkare Research Center | Kumar R.S.S.,Harrisons Malayalam Ltd | Murugesan S.,UPASI Tea Research Foundation
Journal of the Science of Food and Agriculture | Year: 2010

Background: Quality of tea depends on the cultivar and climatic conditions. Biochemical pathways within the plant and climatic factors can result in noticeable changes in chemical composition, which determine the quality of tea. Black tea quality attributes are influenced by various forms of catechins, namely gallated, non-gallated, dihydroxylated and trihydroxylated catechins and their ratios. Hence the variations in grouped catechins and their synthesizing enzyme in relation to quality of south Indian black tea grown in different seasons and different cultivars were studied. Results: Gallated, non-gallated, dihydroxylated, trihydroxylated catechins and catechin index were significantly higher in crop shoots harvested during summer. A significant and wide diversity in various forms of catechins was noticed among the cultivars tested. Among the cultivars, UPASI-3 registered the higher amount of various forms of catechins and activity of phenylalanine ammonia lyase (PAL), followed by UPASI-9 and UPASI-17 respectively, while the lowest amount was exhibited by 'Assam' seedlings and TRI-2043. Conclusion: Overall quality as evaluated by tea tasters was positively correlated to the cultivars and seasons tested. This positive correlation can be attributed to higher levels of grouped catechins and PAL activity. Thus the contents of various forms of catechins could be themost important quality parameter of the south Indian black teas. © 2010 Society of Chemical Industry.

Jayaganesh S.,UPASI Tea Research Foundation | Venkatesan S.,Cavinkare Research Center | Senthurpandian V.K.,Anna University
Asian Journal of Biochemistry | Year: 2011

A study was conducted with different sources of magnesium fertilizers on biochemical parameters like chlorophyll, carotenoids, polyphenols, catechins and amino acid of green leaves in tea. Amino acid and polyphenols are increased due to magnesium sulphate application. Among the various treatments, the application of magnesium sulphate along with reduction of potassium input decreased the biochemical parameters. The content of chlorophyll and carotenoids were higher in magnesium sulphate applied blocks followed by kieserite application. Catechin content was higher due to kieserite and magnesium sulphate applications. After one year of experimentation, the leaf samples collected from the experimental blocks were mini manufactured and analysed for their quality parameters. Theaflavins, thearubigins, total liquor colour and highly polymerised substances were higher in magnesium sulphate and kieserite applied plots. TLC and HPS were higher due to magnesium sulphate application. The different sources of soil applied magnesium directly influenced the amino acid content made of tea and it was higher in magnesium sulphate and magnesium nitrate applied blocks. Flavor index was also estimated for price realization in made tea and it increased due to soil application of magnesium. Among different sources, magnesium sulphate has yielded higher amount of flavor followed by kieserite application. Application as per standard practices along with 50% reduction of potassium fertilizer yielded higher amount of CFC. Water extract content was higher in magnesium sulphate applied blocks and lower in magnesium nitrate application. Green leaf yield and organoleptic evaluation revealed that among different source like magnesium sulphate, magnesite, magnesium nitrate and kieserite, the cost benefit ratio was higher for magnesium sulphate. © 2011 Academic Journals Inc.

Venkatesan S.,Cavinkare Research Center | Jayaganesh S.,UPASI Tea Research Foundation
Research Journal of Phytochemistry | Year: 2010

The excess potassium (K) application to the soil reduces the availability of magnesium (Mg) and vice versa due to antagonism. A pot culture experiment was carried out in which pots were filled with 4 kg of soil to which magnesium sulphate was added externally so as to have 100, 250, 500, 750,1000, 2000, 5000 and 10000 mg of Mg kg-1 of soil. Excess magnesium has induced some toxicity symptoms like development of coppery color along the marginal veins at the initial stage. The mid rib region was also slightly affected. Extensive coppery color developed all over the leaf surface and defoliation of leaf occurred during the final staged of toxicity. The plant, which received 10000 mg of Mg2+ kg-1 died on 20th day after imposing treatments and the plants, which received 5000 mg of Mg2+ kg-1, died on 45th day. The surviving plants were uprooted and separated into leaves, stem, root and soil, on which chemical analysis was carried out. Surprisingly, at any given treatment the accumulation of Mg in root was higher than that of leaf and stem. This study confirmed the antagonism existing between K and Mg and synergism existing between the P and Mg. The ammo acid content increased in tea leaf up to 1000 mg treatment and then gradually decreased. © 2010 Academic Journals Inc.

Sarkar S.,UPASI Tea Research Foundation | Seenivasan S.,UPASI Tea Research Foundation | Asir R.P.S.,UPASI Tea Research Foundation
Journal of Hazardous Materials | Year: 2010

Biodegradation of miticide propargite was carried out in vitro by selected Pseudomonas strains isolated from tea rhizosphere. A total number of 13 strains were isolated and further screened based on their tolerance level to different concentrations of propargite. Five best strains were selected and further tested for their nutritional requirements. Among the different carbon sources tested glucose exhibited the highest growth promoting capacity and among nitrogen sources ammonium nitrate supported the growth to the maximum. The five selected Pseudomonas strain exhibited a range of degradation capabilities. Mineral salts medium (MSM) amended with glucose provided better environment for degradation with the highest degradation potential in strain SPR 13 followed by SPR 8 (71.9% and 69.0% respectively). © 2009.

Rahman V.J.,UPASI Tea Research Foundation | Babu A.,UPASI Tea Research Foundation | Roobakkumar A.,UPASI Tea Research Foundation | Perumalsamy K.,UPASI Tea Research Foundation | And 2 more authors.
Archives of Phytopathology and Plant Protection | Year: 2012

The predatory mite, N. longispinosus preys up on red spider mite, O. coffeae infesting tea in south India. An attempt has been made to determine the predatory potential, prey stage preference and optimum predator-prey ratio of N. longispinosus under laboratory and green house conditions. When 50 adult female O. coffeae were given, the number of adults reduced by eight days along with an increase in the number of predators. The larvae hatched from the eggs laid by O. coffeae were fed by predatory mite. N. longispinosus preyed up on all life stages with a preference to larvae and nymphs of red spider mite. Predator-prey ratios of 1:33 and 1:50 were effective in lab, and 1:25 was found to be effective in green house. These results revealed that N. longispinosus could be used as a successful biocontrol candidate of O. coffeae in tea through augmentation or mass rearing and field release. © 2012 Copyright Taylor and Francis Group, LLC.

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