Mahasen Ranatunga | TECNALIA - Academia.edu (original) (raw)
Papers by Mahasen Ranatunga
![Research paper thumbnail of Utilization of within location non-replicated multi-locational yield trials and GGE biplot methods for testing adaptability of tea [(Camellia sinensis (L.) O. Kuntze)] over diverse environments](https://attachments.academia-assets.com/97548465/thumbnails/1.jpg)
](Indian Journal of Genetics and Plant Breeding (The)
Selection of tea [Camellia sinensis (L.) O. Kuntze] cultivars with wide adaptability over diverse... more Selection of tea [Camellia sinensis (L.) O. Kuntze] cultivars with wide adaptability over diverse environments is an important criteria to get prior information to recommend the cultivar for a particular region. A study was carried out to identify the most adaptable and stable tea genotypes for recommendation in the Up-country tea growing region in Sri Lanka by evaluating several potential tea genotypes for their wide adaptability and stability over diverse environments based on the analysis of GE interaction using within location non-replicated multi-environmental yield trials and GGE biplot methods. Six promising tea genotypes with desirable agronomic traits selected based on preliminary yield trials were evaluated along with a standard check in large scale within location non-replicated multi-locational yield trials at six locations (tea estates) in the Up-country tea growing region in Sri Lanka. The crop yields were recorded by harvesting green leaves in every seven days for thr...
Copyright © 2015 P. A. Nimal Punyasiri et al. This is an open access article distributed under th... more Copyright © 2015 P. A. Nimal Punyasiri et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Chemical analysis of the Sri Lankan tea (Camellia sinensis, L.) germplasm would immensely contribute to the success of the tea breeding programme. However, the polyphenols, particularly catechins (flavan-3-ols), are readily prone to oxidation in the conventional method of sample preparation. Therefore, optimization of the present sample preparation methodology for the profiling of metabolites is much important. Two sample preparation methodologies were compared, fresh leaves (as in the conventional procedures) and freeze-dried leaves (a new procedure), for quantification of major metabolites by employing two cultivars, one is known to be high quality black tea and the other low quality black tea. The amounts of major metabolit...
Sensors and Materials, 2021
![Research paper thumbnail of Advances in Tea [Camellia sinensis (L.) O. Kuntze] Breeding](https://attachments.academia-assets.com/84362581/thumbnails/1.jpg)
](Advances in Plant Breeding Strategies: Nut and Beverage Crops, 2019
Genetic Resources and Crop Evolution, 2018
Tea (Camellia sinensis L.) is the most widely-consumed beverage in the world. The biochemical com... more Tea (Camellia sinensis L.) is the most widely-consumed beverage in the world. The biochemical components of tea leave include polyphenols (catechins and flavonoides), alkaloids (caffeine, theobromine, theophylline, etc.), volatile compounds, polysaccharides, amino acids, lipids and vitamins show a variety of bioactivities. Prolong cross-pollination nature of tea plants have produced considerable heritable variation, resulting in a high level of genetic diversity. The collection and conservation of the cultivars, landraces and wild relatives of the tea plant provides breeders with fundamental materials from which new cultivars are to be developed. The major role of tea breeding is to improve productivity, enhance tolerant to biotic and abiotic stress, and increase tea flavor and quality. Dissection of the genetic basis of these traits provides the potential for accelerating the breeding process by developing new tools such as marker-assisted selection. Therefore present review provides an overview of the biochemical and metabolite diversity of the global tea germplasm and its characterization and utilization.
International Journal of Current Microbiology and Applied Sciences, 2018
International Journal of Biodiversity, 2017
The role of tea germplasm in crop improvement, though well recognized, yet lacks sufficient infor... more The role of tea germplasm in crop improvement, though well recognized, yet lacks sufficient information depriving its optimum use. About 600 accessions are conserved as tea germplasm in Sri Lanka and only 4% have been frequently utilized in breeding. Floral morphological characters are useful descriptors for preliminary characterization of genetic resources and particularly pistil traits are considered as reliable criteria in taxonomical studies of higher plants. The objectives of the present study were to conduct a comprehensive analysis on floral diversity of tea germplasm to determine the nature and extent of genetic structure of tea germplasm and to categorize accessions into major taxa. Eighty-nine accessions from the tea germplasm were characterized using 16 floral traits. Results indicated presence of considerable variation among germplasm accessions. Accessions were categorized into five different groups based on the diversity of floral traits and highly discriminating acces...
The Journal of Horticultural Science and Biotechnology, 2017
ABSTRACT Tea (Camellia sinensis L.) is well known for its biochemical constituents that define th... more ABSTRACT Tea (Camellia sinensis L.) is well known for its biochemical constituents that define the product quality and confer pest and disease resistance. Seven major metabolites – epicatechin (EC), epicatechin gallate (ECg), epigallocatechin (EGC), epigallocatechin gallate (EGCg), caffeine, theobromine, and gallic acid – of 87 beverage type and six non-beverage type tea accessions from Sri Lankan tea germplasm were profiled using HPLC and LC-MS/MS. All seven metabolites varied widely in the beverage type accessions. The non-beverage types only contained gallic acid and epicatechin. Results prove the presence of high EC and ECg contents in green leaves to be a reliable marker for identifying high-quality black tea-producing accessions. High EC and low EGCg contents in green tea leaves appear to enhance traits of resistance to blister blight disease. Significant variations detected in theobromine, caffeine, and total polyphenol content define the affinity of germplasm to the main three tea taxa, and we conclude that C. sinensis ssp. lasiocalyx predominates the Sri Lankan germplasm collection.
International Journal of Food Science, 2016
Flavonol glycosides in tea leaves have been quantified as aglycones, quercetin, myricetin, and ka... more Flavonol glycosides in tea leaves have been quantified as aglycones, quercetin, myricetin, and kaempferol. Occurrence of the said compounds was reported in fruits and vegetable for a long time in association with the antioxidant potential. However, data on flavonols in tea were scanty and, hence, this study aims to envisage the flavonol content in a representative pool of accessions present in the Sri Lankan tea germplasm. Significant amounts of myricetin, quercetin, and kaempferol have been detected in the beverage type tea accessions of the Sri Lankan tea germplasm. This study also revealed that tea is a good source of flavonol glycosides. TheCamellia sinensisvar.sinensisshowed higher content of myricetin, quercetin, and total flavonols than var.assamicaand ssp.lasiocalyx. Therefore flavonols and their glycosides can potentially be used in chemotaxonomic studies of tea germplasm. The nonbeverage type cultivars, especiallyCamellia rosafloraandCamellia japonicaRed along with the exo...
Journal of Analytical Methods in Chemistry, 2015
Chemical analysis of the Sri Lankan tea (Camellia sinensis, L.) germplasm would immensely contrib... more Chemical analysis of the Sri Lankan tea (Camellia sinensis, L.) germplasm would immensely contribute to the success of the tea breeding programme. However, the polyphenols, particularly catechins (flavan-3-ols), are readily prone to oxidation in the conventional method of sample preparation. Therefore, optimization of the present sample preparation methodology for the profiling of metabolites is much important. Two sample preparation methodologies were compared, fresh leaves (as in the conventional procedures) and freeze-dried leaves (a new procedure), for quantification of major metabolites by employing two cultivars, one is known to be high quality black tea and the other low quality black tea. The amounts of major metabolites such as catechins, caffeine, gallic acid, and theobromine, recorded in the new sampling procedure via freeze-dried leaves, were significantly higher than those recorded in the conventional sample preparation procedure. Additionally new method required less a...
Resumen Formación de una colección testigo preliminar de recursos genéticos de té (Camellia sinen... more Resumen Formación de una colección testigo preliminar de recursos genéticos de té (Camellia sinensis (L.) O. Kuntze) en Sri Lanka Se destaca la necesidad de adoptar un método más amplio, con una progresión lógica que vaya de la conservación al or-denamiento y utilización de los recursos genéticos de té en Sri Lanka. Se recogió información disponible sobre taxonomía, pedigree, origen geográfico e historia del cultivo de 500 accesiones de germoplas-ma conservadas en el Instituto de Inves-tigación de Té en Sri Lanka. Los recursos genéticos de té comprenden tanto tipos bebibles como no bebibles, y la mayoría de las accesiones son de la especie C. sinensis, con muy poca representación de especies silvestres y otras relaciona-das con ellas. No se han caracterizado adecuadamente los rasgos agronómicos de la mayoría de las accesiones de ger-moplasma. El empleo recurrente de los mismos progenitores en los programas de cultivo ha restringido aún más la diversidad del patrimonio genético de té...
Success of tea micro-propagation is hindered by severe microbial contamination of explants. This ... more Success of tea micro-propagation is hindered by severe microbial contamination of explants. This study aimed at developing an effective sterilization protocol by combin- ing pre harvesting sterilization measures with five differ- ent surface sterilization protocols using nodal explants taken from six new tea cultivars. Attempts were also made to identify the most abundant contaminants in tea and to incorporate fungicides to the culture medium in order to control them. Impact of pre harvesting sterihza- tion measures (maintaining mother bushes inside a propagator with a fungicide spraying schedule) to reduce contaminations of nodal explants was inconsistent among accessions. Among the five surface sterilization techniques tested, treatment with 0.1% HgCl2 for 10 minutes yielded the best results as it improved the number of clean and alive nodal explants (45.25 %). It was found that treatments with acidified bleach and bleach, ethanol and Tween 20 mixture were ineffective in reduction of contamination (>75%) and treatments with acidified bleach and benlate mixture where cuttings were kept overnight in a refrigerator resulted severe browning of explants (44.08%). Results revealed that two fungi Pestalotiopsis and Aspelgitlus were the most prominent con- taminants found in tea stern nodal culture resulted 67.50/o and 25% contaminations of explant respectively. When fungicides (Hexaconazole and Chlorothalonil) were added to the MS medium, high survival percentage of explants (>60%) were observed As this was a prelimi- nary study further studies in this regard is suggested to explore possibility of replacing HgCl2 by fungicide added medium.
No: 307 Plant Science and Forestry Owing to the long-term nature of conventional tea cultivar dev... more No: 307 Plant Science and Forestry Owing to the long-term nature of conventional tea cultivar development programme, Tea Research Institute of Sri Lanka has perfected an embryo culture protocol for hybrid seeds and successfully integrated it to accelerate the release of new tea cultivars. Unless the resultant regenerants are genetically similar and phenotypically uniform, they cannot be used in the breeding programmes. This study was aimed to assess the genetic similarity of embryo cultured tea plants using morphological and RAPD markers. Three embryo cultured plant progenies generated from controlled hybridization between TRI 2025 × PK 2, TRI 3013 × DT 95 and TRI 3013 × C. sasanqua were assessed with 28 standard morphological descriptors and six RAPD markers. Results of both quantitative and qualitative morphological analysis indicated that only one and two individuals from the cross combinations of TRI 2025 × PK2 and TRI 3013 × DT 95, respectively were not phenotypically similar t...
Seeds obtained from bi- and poly-clonal seed gardens with different parental combinations of know... more Seeds obtained from bi- and poly-clonal seed gardens with different parental combinations of known VP cultivars were used to establish seedling plantations and their performances were evaluated in comparison to standard VP cultivars in on-station trials representing four regions for over two pruning cycles. Yield and tolerance to biotic and abiotic stresses were assessed to identify promising seed materials. Seed materials collected from from Reucastle, St Coombs, Anhettigama, Salawa, Halpe, Karadupona and Sapumalkanda seed gardens recorded yields comparable to standard cultivars, depending on the regions where testing was carried out. About 70% of the individual seedlings in the above seed sources showed tolerance to shot- hole borer in the trial carried out in Uva. Majority of the seed sources were found to be tolerant / moderately tolerant to canker (Macrophoma) in the low country regional trial while majority of seed sources showed their high levels of tolerance to moisture stre...
At the Tea Research Institute of Sri Lanka conservation aspects on tea germplasm in ex-situ gene ... more At the Tea Research Institute of Sri Lanka conservation aspects on tea germplasm in ex-situ gene bank as living collection was initiated in 1986. Currently, over 600 accessions are being maintained in field gene bank and efforts have been taken to characterize, evaluate and utilize them in the tea breeding program. This paper highlights the significant achievements in the areas of germplasm collection, conservation, characterization and evaluation and their use in tea breeding program giving prominence to the cost effective complementary strategies adopted in germplasm conservation and holistic approaches followed in germplasm characterization to facilitate managerial activities. Over the years, the methods for detecting genetic diversity have expanded from analysis of discrete morphological variants, to biochemical approaches and to co-efficient of pedigree analysis to methods based on DNA markers. This kind of an approach, where genetic diversity assessment is supplemented with a ...
Tea is the second most popular and economically important beverage in the world. The chemical con... more Tea is the second most popular and economically important beverage in the world. The chemical constituents of tea flush (Camellia sinensis, L.) play a major role in defining the quality of the final product. However, limited work has been documented on the quantitative analysis of the variation of a broad range of metabolites in tea cultivars. The present study is the first attempt on a large scale metabolite profiling of the Sri Lankan tea germplasm using high throughput techniques. Tea flush samples of 87 germplasm accessions collected from the ex situ field gene bank of the Tea Research Institute of Sri Lanka were freeze-dried and analyzed for total polyphenols (TPP) by the ISO/14502-1 spectrophotometric method. The quantitative analysis of six major metabolites (caffeine, four catechins and theobromine) was performed by the ISO/14502-2 method usingAgilent 1260 Infinity HPLC system. The TPP content varied from 153.08±11.64 to 287.88±6.53 mg/g dry weight (dw). The contents of the ...
Indian Journal of Genetics and Plant Breeding (The)
Selection of tea [Camellia sinensis (L.) O. Kuntze] cultivars with wide adaptability over diverse... more Selection of tea [Camellia sinensis (L.) O. Kuntze] cultivars with wide adaptability over diverse environments is an important criteria to get prior information to recommend the cultivar for a particular region. A study was carried out to identify the most adaptable and stable tea genotypes for recommendation in the Up-country tea growing region in Sri Lanka by evaluating several potential tea genotypes for their wide adaptability and stability over diverse environments based on the analysis of GE interaction using within location non-replicated multi-environmental yield trials and GGE biplot methods. Six promising tea genotypes with desirable agronomic traits selected based on preliminary yield trials were evaluated along with a standard check in large scale within location non-replicated multi-locational yield trials at six locations (tea estates) in the Up-country tea growing region in Sri Lanka. The crop yields were recorded by harvesting green leaves in every seven days for thr...
Copyright © 2015 P. A. Nimal Punyasiri et al. This is an open access article distributed under th... more Copyright © 2015 P. A. Nimal Punyasiri et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Chemical analysis of the Sri Lankan tea (Camellia sinensis, L.) germplasm would immensely contribute to the success of the tea breeding programme. However, the polyphenols, particularly catechins (flavan-3-ols), are readily prone to oxidation in the conventional method of sample preparation. Therefore, optimization of the present sample preparation methodology for the profiling of metabolites is much important. Two sample preparation methodologies were compared, fresh leaves (as in the conventional procedures) and freeze-dried leaves (a new procedure), for quantification of major metabolites by employing two cultivars, one is known to be high quality black tea and the other low quality black tea. The amounts of major metabolit...
Sensors and Materials, 2021
Advances in Plant Breeding Strategies: Nut and Beverage Crops, 2019
Genetic Resources and Crop Evolution, 2018
Tea (Camellia sinensis L.) is the most widely-consumed beverage in the world. The biochemical com... more Tea (Camellia sinensis L.) is the most widely-consumed beverage in the world. The biochemical components of tea leave include polyphenols (catechins and flavonoides), alkaloids (caffeine, theobromine, theophylline, etc.), volatile compounds, polysaccharides, amino acids, lipids and vitamins show a variety of bioactivities. Prolong cross-pollination nature of tea plants have produced considerable heritable variation, resulting in a high level of genetic diversity. The collection and conservation of the cultivars, landraces and wild relatives of the tea plant provides breeders with fundamental materials from which new cultivars are to be developed. The major role of tea breeding is to improve productivity, enhance tolerant to biotic and abiotic stress, and increase tea flavor and quality. Dissection of the genetic basis of these traits provides the potential for accelerating the breeding process by developing new tools such as marker-assisted selection. Therefore present review provides an overview of the biochemical and metabolite diversity of the global tea germplasm and its characterization and utilization.
International Journal of Current Microbiology and Applied Sciences, 2018
International Journal of Biodiversity, 2017
The role of tea germplasm in crop improvement, though well recognized, yet lacks sufficient infor... more The role of tea germplasm in crop improvement, though well recognized, yet lacks sufficient information depriving its optimum use. About 600 accessions are conserved as tea germplasm in Sri Lanka and only 4% have been frequently utilized in breeding. Floral morphological characters are useful descriptors for preliminary characterization of genetic resources and particularly pistil traits are considered as reliable criteria in taxonomical studies of higher plants. The objectives of the present study were to conduct a comprehensive analysis on floral diversity of tea germplasm to determine the nature and extent of genetic structure of tea germplasm and to categorize accessions into major taxa. Eighty-nine accessions from the tea germplasm were characterized using 16 floral traits. Results indicated presence of considerable variation among germplasm accessions. Accessions were categorized into five different groups based on the diversity of floral traits and highly discriminating acces...
The Journal of Horticultural Science and Biotechnology, 2017
ABSTRACT Tea (Camellia sinensis L.) is well known for its biochemical constituents that define th... more ABSTRACT Tea (Camellia sinensis L.) is well known for its biochemical constituents that define the product quality and confer pest and disease resistance. Seven major metabolites – epicatechin (EC), epicatechin gallate (ECg), epigallocatechin (EGC), epigallocatechin gallate (EGCg), caffeine, theobromine, and gallic acid – of 87 beverage type and six non-beverage type tea accessions from Sri Lankan tea germplasm were profiled using HPLC and LC-MS/MS. All seven metabolites varied widely in the beverage type accessions. The non-beverage types only contained gallic acid and epicatechin. Results prove the presence of high EC and ECg contents in green leaves to be a reliable marker for identifying high-quality black tea-producing accessions. High EC and low EGCg contents in green tea leaves appear to enhance traits of resistance to blister blight disease. Significant variations detected in theobromine, caffeine, and total polyphenol content define the affinity of germplasm to the main three tea taxa, and we conclude that C. sinensis ssp. lasiocalyx predominates the Sri Lankan germplasm collection.
International Journal of Food Science, 2016
Flavonol glycosides in tea leaves have been quantified as aglycones, quercetin, myricetin, and ka... more Flavonol glycosides in tea leaves have been quantified as aglycones, quercetin, myricetin, and kaempferol. Occurrence of the said compounds was reported in fruits and vegetable for a long time in association with the antioxidant potential. However, data on flavonols in tea were scanty and, hence, this study aims to envisage the flavonol content in a representative pool of accessions present in the Sri Lankan tea germplasm. Significant amounts of myricetin, quercetin, and kaempferol have been detected in the beverage type tea accessions of the Sri Lankan tea germplasm. This study also revealed that tea is a good source of flavonol glycosides. TheCamellia sinensisvar.sinensisshowed higher content of myricetin, quercetin, and total flavonols than var.assamicaand ssp.lasiocalyx. Therefore flavonols and their glycosides can potentially be used in chemotaxonomic studies of tea germplasm. The nonbeverage type cultivars, especiallyCamellia rosafloraandCamellia japonicaRed along with the exo...
Journal of Analytical Methods in Chemistry, 2015
Chemical analysis of the Sri Lankan tea (Camellia sinensis, L.) germplasm would immensely contrib... more Chemical analysis of the Sri Lankan tea (Camellia sinensis, L.) germplasm would immensely contribute to the success of the tea breeding programme. However, the polyphenols, particularly catechins (flavan-3-ols), are readily prone to oxidation in the conventional method of sample preparation. Therefore, optimization of the present sample preparation methodology for the profiling of metabolites is much important. Two sample preparation methodologies were compared, fresh leaves (as in the conventional procedures) and freeze-dried leaves (a new procedure), for quantification of major metabolites by employing two cultivars, one is known to be high quality black tea and the other low quality black tea. The amounts of major metabolites such as catechins, caffeine, gallic acid, and theobromine, recorded in the new sampling procedure via freeze-dried leaves, were significantly higher than those recorded in the conventional sample preparation procedure. Additionally new method required less a...
Resumen Formación de una colección testigo preliminar de recursos genéticos de té (Camellia sinen... more Resumen Formación de una colección testigo preliminar de recursos genéticos de té (Camellia sinensis (L.) O. Kuntze) en Sri Lanka Se destaca la necesidad de adoptar un método más amplio, con una progresión lógica que vaya de la conservación al or-denamiento y utilización de los recursos genéticos de té en Sri Lanka. Se recogió información disponible sobre taxonomía, pedigree, origen geográfico e historia del cultivo de 500 accesiones de germoplas-ma conservadas en el Instituto de Inves-tigación de Té en Sri Lanka. Los recursos genéticos de té comprenden tanto tipos bebibles como no bebibles, y la mayoría de las accesiones son de la especie C. sinensis, con muy poca representación de especies silvestres y otras relaciona-das con ellas. No se han caracterizado adecuadamente los rasgos agronómicos de la mayoría de las accesiones de ger-moplasma. El empleo recurrente de los mismos progenitores en los programas de cultivo ha restringido aún más la diversidad del patrimonio genético de té...
Success of tea micro-propagation is hindered by severe microbial contamination of explants. This ... more Success of tea micro-propagation is hindered by severe microbial contamination of explants. This study aimed at developing an effective sterilization protocol by combin- ing pre harvesting sterilization measures with five differ- ent surface sterilization protocols using nodal explants taken from six new tea cultivars. Attempts were also made to identify the most abundant contaminants in tea and to incorporate fungicides to the culture medium in order to control them. Impact of pre harvesting sterihza- tion measures (maintaining mother bushes inside a propagator with a fungicide spraying schedule) to reduce contaminations of nodal explants was inconsistent among accessions. Among the five surface sterilization techniques tested, treatment with 0.1% HgCl2 for 10 minutes yielded the best results as it improved the number of clean and alive nodal explants (45.25 %). It was found that treatments with acidified bleach and bleach, ethanol and Tween 20 mixture were ineffective in reduction of contamination (>75%) and treatments with acidified bleach and benlate mixture where cuttings were kept overnight in a refrigerator resulted severe browning of explants (44.08%). Results revealed that two fungi Pestalotiopsis and Aspelgitlus were the most prominent con- taminants found in tea stern nodal culture resulted 67.50/o and 25% contaminations of explant respectively. When fungicides (Hexaconazole and Chlorothalonil) were added to the MS medium, high survival percentage of explants (>60%) were observed As this was a prelimi- nary study further studies in this regard is suggested to explore possibility of replacing HgCl2 by fungicide added medium.
No: 307 Plant Science and Forestry Owing to the long-term nature of conventional tea cultivar dev... more No: 307 Plant Science and Forestry Owing to the long-term nature of conventional tea cultivar development programme, Tea Research Institute of Sri Lanka has perfected an embryo culture protocol for hybrid seeds and successfully integrated it to accelerate the release of new tea cultivars. Unless the resultant regenerants are genetically similar and phenotypically uniform, they cannot be used in the breeding programmes. This study was aimed to assess the genetic similarity of embryo cultured tea plants using morphological and RAPD markers. Three embryo cultured plant progenies generated from controlled hybridization between TRI 2025 × PK 2, TRI 3013 × DT 95 and TRI 3013 × C. sasanqua were assessed with 28 standard morphological descriptors and six RAPD markers. Results of both quantitative and qualitative morphological analysis indicated that only one and two individuals from the cross combinations of TRI 2025 × PK2 and TRI 3013 × DT 95, respectively were not phenotypically similar t...
Seeds obtained from bi- and poly-clonal seed gardens with different parental combinations of know... more Seeds obtained from bi- and poly-clonal seed gardens with different parental combinations of known VP cultivars were used to establish seedling plantations and their performances were evaluated in comparison to standard VP cultivars in on-station trials representing four regions for over two pruning cycles. Yield and tolerance to biotic and abiotic stresses were assessed to identify promising seed materials. Seed materials collected from from Reucastle, St Coombs, Anhettigama, Salawa, Halpe, Karadupona and Sapumalkanda seed gardens recorded yields comparable to standard cultivars, depending on the regions where testing was carried out. About 70% of the individual seedlings in the above seed sources showed tolerance to shot- hole borer in the trial carried out in Uva. Majority of the seed sources were found to be tolerant / moderately tolerant to canker (Macrophoma) in the low country regional trial while majority of seed sources showed their high levels of tolerance to moisture stre...
At the Tea Research Institute of Sri Lanka conservation aspects on tea germplasm in ex-situ gene ... more At the Tea Research Institute of Sri Lanka conservation aspects on tea germplasm in ex-situ gene bank as living collection was initiated in 1986. Currently, over 600 accessions are being maintained in field gene bank and efforts have been taken to characterize, evaluate and utilize them in the tea breeding program. This paper highlights the significant achievements in the areas of germplasm collection, conservation, characterization and evaluation and their use in tea breeding program giving prominence to the cost effective complementary strategies adopted in germplasm conservation and holistic approaches followed in germplasm characterization to facilitate managerial activities. Over the years, the methods for detecting genetic diversity have expanded from analysis of discrete morphological variants, to biochemical approaches and to co-efficient of pedigree analysis to methods based on DNA markers. This kind of an approach, where genetic diversity assessment is supplemented with a ...
Tea is the second most popular and economically important beverage in the world. The chemical con... more Tea is the second most popular and economically important beverage in the world. The chemical constituents of tea flush (Camellia sinensis, L.) play a major role in defining the quality of the final product. However, limited work has been documented on the quantitative analysis of the variation of a broad range of metabolites in tea cultivars. The present study is the first attempt on a large scale metabolite profiling of the Sri Lankan tea germplasm using high throughput techniques. Tea flush samples of 87 germplasm accessions collected from the ex situ field gene bank of the Tea Research Institute of Sri Lanka were freeze-dried and analyzed for total polyphenols (TPP) by the ISO/14502-1 spectrophotometric method. The quantitative analysis of six major metabolites (caffeine, four catechins and theobromine) was performed by the ISO/14502-2 method usingAgilent 1260 Infinity HPLC system. The TPP content varied from 153.08±11.64 to 287.88±6.53 mg/g dry weight (dw). The contents of the ...