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Screening of Adoptive Elite Tea (Camellia sinensis) Clones
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作者 Muhammad Razaq Hasnain Alam +1 位作者 Muhammad Ishfaq Salahuddin 《Journal of Northeast Agricultural University(English Edition)》 CAS 2015年第4期33-36,共4页
The research screening of adoptive elite tea clones was conducted at NTRI, Mansehra during 2011-2012. Nine clones 101Aa, 105aa, 108aa, 561aa, ll7aa, 219ab, 470bb and 180bd were evaluated for seedling performance. Rand... The research screening of adoptive elite tea clones was conducted at NTRI, Mansehra during 2011-2012. Nine clones 101Aa, 105aa, 108aa, 561aa, ll7aa, 219ab, 470bb and 180bd were evaluated for seedling performance. Randomized complete block design was used with three replications. Data was recorded on various morphological characters after 8 months. The results showed that high survival percentage, shoot length, number of roots plant-1, number of leaves plant1 and root length were observed in clone 105aa. While the highest fresh weight and dry weight of leaves were observed in clones 117aa and 105aa. The clone 105aa was drought resistant, high survival percentage and root growth. On the basis of the results, clone 105aa was recommended for cultivation through cuttings in the hilly areas of Pakistan where unequal rainfall distribution was a major hitch. 展开更多
关键词 tea camellia sinensis clone
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Genetic analyses of ancient tea trees provide insights into the breeding history and dissemination of Chinese Assam tea(Camellia sinensis var.assamica)
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作者 Miao-Miao Li Muditha K.Meegahakumbura +5 位作者 Moses C.Wambulwa Kevin S.Burgess Michael Möller Zong-Fang Shen De-Zhu Li Lian-Ming Gao 《Plant Diversity》 SCIE CAS CSCD 2024年第2期229-237,共9页
Chinese Assam tea(Camellia sinensis var.assamica)is an important tea crop with a long history of cultivation in Yunnan,China.Despite its potential value as a genetic resource,its genetic diversity and domestication/br... Chinese Assam tea(Camellia sinensis var.assamica)is an important tea crop with a long history of cultivation in Yunnan,China.Despite its potential value as a genetic resource,its genetic diversity and domestication/breeding history remain unclear.To address this issue,we genotyped 469 ancient tea plant trees representing 26 C.sinensis var.assamica populations,plus two of its wild relatives(six and three populations of C.taliensis and C.crassicolumna,respectively)using 16 nuclear microsatellite loci.Results showed that Chinese Assam tea has a relatively high,but comparatively lower gene diversity(H_(S)=0.638)than the wild relative C.crassicolumna(H_S=0.658).Clustering in STRUCTURE indicated that Chinese Assam tea and its two wild relatives formed distinct genetic groups,with considerable interspecific introgression.The Chinese Assam tea accessions clustered into three gene pools,corresponding well with their geographic distribution.However,New Hybrids analysis indicated that 68.48%of ancient Chinese Assam tea plants from Xishuangbanna were genetic intermediates between the Puer and Lincang gene pools.In addition,10%of the ancient Chinese Assam tea individuals were found to be hybrids between Chinese Assam tea and C.taliensis.Our results suggest that Chinese Assam tea was domesticated separately in three gene pools(Puer,Lincang and Xishuangbanna)in the Mekong River valley and that the hybrids were subsequently selected during the domestication process.Although the domestication history of Chinese Assam tea in southwestern Yunnan remains complex,our results will help to identify valuable genetic resources that may be useful in future tea breeding programs. 展开更多
关键词 tea plant Hybrid origin Genetic diversity Domestication history camellia sinensis var.assamica camellia taliensis
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Variation in Catechin Composition of Popularly Cultivated Tea Clones in East Africa (Kenya)
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作者 Leonida Cherotich Samson M. Kamunya +4 位作者 Amos Alakonya Solomon W. Msomba Marie A. Uwimana John K. Wanyoko Phillip O. Owuor 《American Journal of Plant Sciences》 2013年第3期628-640,共13页
Tea polyphenols and catechins have gained prominence in determination of tea quality. Tea leaves contain large amounts of catechins and their derivatives and these have shown positive effects on human health. An exper... Tea polyphenols and catechins have gained prominence in determination of tea quality. Tea leaves contain large amounts of catechins and their derivatives and these have shown positive effects on human health. An experiment was carried out to determine the level of catechins and polyphenols in 20 new clones found in two distinct tea growing areas. The trial comprising twenty clones was established in two distinct sites in Kenya using randomized complete block design with three replicates and consisted of 10 popular cultivars widely cultivated in the Lake Victoria Basin and additional 10 newly improved clones. Tea leaf samples were collected across two seasons;dry and wet seasons. Tea quality parameters entailing catechins, caffeine and total polyphenols was generated for the 20 clones across the two seasons and sites. The ISO 14502-1 and ISO 14502-1:2005 procedures were used for polyphenol and catechin analyses, respectively. The ANOVA results generated indicated that the level of catechins and polyphenols in tea were significantly different (p 0.05) and varietal dependent. Generally, the assam varieties had higher levels of catechins and polyphenols than the chinary and cambod varieties, indicating why they are popularly cultivated in the East African region and whose tea quality is highly regarded. Furthermore, the results from principle component analysis (PCA) grouped the clones into three major clusters with one comprising of high quality assam varieties, a mixture of moderate quality assam, cambod and chinary varieties and low catechin content assam anthocyanin-rich variety. It is concluded that the level of catechins in tea plants are varietal dependent, although environmental stress has effects on the synthesis of flavanoids. The results demonstrated that the differences in the accumulation of catechins among the tea clones could be important for the discrimination of clonal diversity. 展开更多
关键词 tea Health camellia sinensis CATECHINS VARIATION Kenya
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Comparative Effect of Ca, K, Mn and B on Post-Drought Stress Recovery in Tea [<i>Camellia sinensis</i>(L.) O <i>Kuntze</i>] 被引量:6
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作者 Hrishikesh Upadhyaya Biman K. Dutta +1 位作者 Lingaraj Sahoo Sanjib K. Panda 《American Journal of Plant Sciences》 2012年第4期443-460,共18页
Tea (Camellia sinensis) is one of the most important economic crops. Being perennial in nature, tea plant often experiences natural drought, which affects its growth and productivity. The present investigation was und... Tea (Camellia sinensis) is one of the most important economic crops. Being perennial in nature, tea plant often experiences natural drought, which affects its growth and productivity. The present investigation was undertaken to understand the mechanism of post-drought stress recovery on rehydration and the effect of nutrients in the recovery process of the selected clones of Camellia sinensis L. (TV-1, TV-20, TV-29 & TV-30). The results demonstrated that decrease in relative water content (RWC), dry mass of leaf and antioxidants like-ascorbate and glutathione in all the tested clones, as a result of imposed water stress, which caused damage was not permanent. Increase in phenolic content with decrease in O2-, H2O2 and lipid peroxidation was indication of the recovery of stress induced oxidative damage following the post stress rehydration. Further, the post drought recovery was enhanced by foliar spray of K, Ca, Mn & B. Differential activities of enzymes like SOD, CAT, POX, GR and PPO in response to foliar spray of nutrients in rehydrated plant improved the recovery process. The present study reveals that the tested nutrients (K, Ca, Mn & B) showed some positive response in influencing growth and antioxidative responses during post drought recovery process, where K and Ca showed comparatively better effect in improving post drought recovery potential in tea plant. 展开更多
关键词 DROUGHT POST DROUGHT RECOVERY (PDR) Calcium Potassium Boron Manganese camellia sinensis (tea)
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Quantitative Analysis of ATP Sulfurylase and Selenocysteine Methyltransferase Gene Expression in Different Organs of Tea Plant (<i>Camellia sinensis</i>) 被引量:3
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作者 Shaoqiang Tao Juan Li +4 位作者 Xungang Gu Yanan Wang Qiang Xia Bing Qin Lin Zhu 《American Journal of Plant Sciences》 2012年第1期51-59,共9页
Tea plant (Camellia sinensis) has unique biological features for the study of cellular and molecular mechanisms, an evergreen broad-leaved woody plant which can accumulate selenium in soil abundant of Selenium. Expres... Tea plant (Camellia sinensis) has unique biological features for the study of cellular and molecular mechanisms, an evergreen broad-leaved woody plant which can accumulate selenium in soil abundant of Selenium. Expression of the genes related to Selenium (Se) metabolism is an adaptation to the soil environment for a long period. The purpose of the present study was to explore if there exist differences of expression about these genes in tea plant between growing in Selenium-abundant and normal soil. A quantitative real-time reverse transcription polymerase chain reaction (Q-RT-PCR) assay was done for quantification of ATP sulfurylase (APS) and selenocysteine methyltransferase (SMT) mRNA normalized to Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) gene in tea plant. Young leaves, mature leaves and tender roots from tea plants growing in soil abundant of Selenium were respectively obtained from Shitai County, Anhui Province, and also the relevant materials of the selenium un-enriched tea plant planted at agricultural garden of Ahui Agriculture University were taken as control for real-time PCR analysis. The results showed that APS1, APS2 and SMT expression levels for either young or mature leaves in selenium-enriched tea plant were lower than that in ordinary (selenium un-enriched) tea plant. In contrast, the APS1, APS2 and SMT expression level of roots in selenium-enriched tea plant were all higher than that in ordinary tea plant. APS1 gene expression level of roots in selenium-enriched tea plant was about 1.6 times higher than that in the ordinary tea plant, APS2 gene expression level was about 4.8-fold higher than that in the ordinary tea plant, SMT gene expression level was about 3.3 times higher than that in the ordinary tea plant. Among various tissues of selenium-enriched tea plant, APS1 gene relative expression level of young leaves was similar to or slightly higher than mature leaves, and the one of roots was the lowest among them;APS2 gene relative expression level of young leaves was similar to or slightly higher than the roots, and the one of mature leaves was the lowest among them;SMT gene relative expression level of young leaves was similar to or slightly higher than mature leaves, and the one of roots was the highest among them. Our results suggest that there existed correlation between selenium and expression levels of these genes. 展开更多
关键词 Quantitative Real-Time Polymerase Chain Reaction ATP Sulfurylase SELENOCYSTEINE METHYLTRANSFERASE tea Plant (camellia sinensis)
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Identification of miRNAs and target genes regulating catechin biosynthesis in tea (Camellia sinensis) 被引量:3
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作者 SUN Ping ZHANG Zhen-lu +5 位作者 ZHU Qiu-fang ZHANG Guo-ying XIANG Ping LIN Yu-ling LAI Zhong-xiong LIN Jin-ke 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2018年第5期1154-1164,共11页
Micro RNAs(miRNAs) are endogenous non-protein-coding small RNAs that play crucial and versatile regulatory roles in plants. Using a computational identification method, we identified 55 conserved miRNAs in tea(Came... Micro RNAs(miRNAs) are endogenous non-protein-coding small RNAs that play crucial and versatile regulatory roles in plants. Using a computational identification method, we identified 55 conserved miRNAs in tea(Camellia sinensis) by aligning miRNA sequences of different plant species with the transcriptome library of tea strain 1005. We then used quantitative real-time PCR(qRT-PCR) to analyze the expression of 31 identified miRNAs in tea leaves of different ages, thereby verifying the existence of these miRNAs and confirming the reliability of the computational identification method. We predicted which miRNAs were involved in catechin synthesis using ps RNAtarget Software based on conserved miRNAs and catechin synthesis pathway-related genes. Then, we used RNA ligase-mediated rapid amplification of c DNA ends(RLM-RACE) to obtain seven miRNAs cleaving eight catechin synthesis pathway-related genes including chalcone synthase(CHS), chalcone isomerase(CHI), dihydroflavonol 4-reductase(DFR), anthocyanidin reductase(ANR), leucoanthocyanidin reductase(LAR), and flavanone 3-hydroxylase(F3H). An expression analysis of miRNAs and target genes revealed that miR529d and miR156 g-3 p were negatively correlated with their targets CHI and F3H, respectively. The expression of other miRNAs was not significantly related to their target genes in the catechin synthesis pathway. The RLM-RACE results suggest that catechin synthesis is regulated by miRNAs that can cleave genes involved in catechin synthesis. 展开更多
关键词 teacamellia sinensis miRNA catechin synthesis gene
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Induced Polyploidy as a Tool for Increasing Tea(Camellia sinensis L.) Production 被引量:1
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作者 Hasnain Alam Muhammad Razaq Salahuddin 《Journal of Northeast Agricultural University(English Edition)》 CAS 2015年第3期43-47,共5页
Tea (Camellia sinensis L.) represents different ploidy levels. In the present paper, we reviewed the recent data on the diploid, aneuploid and polyploid formed their origin and chemically induced polyploidy and pred... Tea (Camellia sinensis L.) represents different ploidy levels. In the present paper, we reviewed the recent data on the diploid, aneuploid and polyploid formed their origin and chemically induced polyploidy and predicted it role in teagenetic improvement for better yield. Different polidy levels had different effects on tea physiology. Tetraploid and triploid had more vigour and hardness due to increased size of cells, while triploid could have even more vigours due to increased size of cells and sterilities. Chemically induced polyploidy had been found an important tool for improving plant physiology and production, therefore, induced polyploids should be produced to overcome the problem of low yield and limited rainfall in tea growing areas. 展开更多
关键词 tea camellia sinensis POLYPLOIDY
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Peroxidase Inhibition and Antioxidant Activity of Bulk-Marketed Black Tea (<i>Camellia sinensis</i>L.) from the Democratic Republic of the Congo 被引量:1
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作者 Nadege Ngombe Kabamba Joyce Mbuyi Katalayi +8 位作者 Jimmy Kabeya Kabengele Grace Nkakapen Djoumbissi Marie Joe Kabongo Kapinga Thé ophile Mbemba Fundu Dieudonné Tshitenge Tshitenge Pascal Dibungi T. Kalenda Paulin Mutwale Kapepula 《Journal of Biosciences and Medicines》 2019年第9期66-80,共15页
The widely known leaves of Camellia sinensis (L.) derive the most consumed beverage globally. All over the world, like in the Democratic Republic of the Congo (DR Congo), they are marketed in the form of packaged and ... The widely known leaves of Camellia sinensis (L.) derive the most consumed beverage globally. All over the world, like in the Democratic Republic of the Congo (DR Congo), they are marketed in the form of packaged and in bulk black tea. The aim of this study was to report the microscopic botanical features, the chromatographic fingerprints, the antioxidant activities, and the peroxidase inhibition of bulk-marketed black teas consumed in DR Congo. The microscopic analysis of powders from unpackaged black tea marketed in DR Congo allowed the identification of specific microscopical features, which are characteristic to C. sinensis (L.) such as numerous asterosclerites, numerous fragments of unicellular trichomes;fragments of abaxial epidermis consisting of cells with slightly wavy walls, numerous anomocytic stomata, and the detection of biological contaminants, e.g. the dust mites. TLC and HPLC analysis indicated that flavonoids (hyperoside, rutin) and phenolic acids (chlorogenic acid, gallic acid) were major phenolic compounds, along with other secondary metabolites. Aqueous extracts from all bulk-marketed black teas exhibited good antioxidant activities at the concentrations range of 1 - 20 μg·mL-1 using in vitro ABTS and DPPH assays. These extracts showed equally inhibitory effects on myeloperoxidase (MPO) and horseradish peroxidase (HRP) activities at the concentration ranges of 1 - 20 μg·mL-1 and 20 - 100 μg·mL-1 respectively. Bulk-marketed black teas consumed in DR Congo possess antioxidant and anti-inflammatory properties comparable to packaged Ceylon tea largely marketed. The observed bioactivities support the health benefits of the consumed black tea by Congolese people, despite the storage conditions to be improved in order to preserve its nutritional and therapeutic assets. 展开更多
关键词 Antioxidant Activity Black tea camellia sinensis HRP L-012 MITES MYELOPEROXIDASE
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Genome-Wide Characterization of the Cellulose Synthase Gene Superfamily in Tea Plants(Camellia sinensis)
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作者 Qianqian Li Qi Zhao +2 位作者 Xinzhuan Yao Baohui Zhang Litang Lu 《Phyton-International Journal of Experimental Botany》 SCIE 2022年第10期2163-2189,共27页
The cellulose synthase gene superfamily,including Cellulose synthase A(CesA)and cellulose synthase-like(Csl)gene families,is responsible for the synthesis of cellulose and hemicellulose,respectively.The CesA/Csl genes... The cellulose synthase gene superfamily,including Cellulose synthase A(CesA)and cellulose synthase-like(Csl)gene families,is responsible for the synthesis of cellulose and hemicellulose,respectively.The CesA/Csl genes are vital for abiotic stress resistance and shoot tenderness regulation of tea plants(Camellia sinensis).However,the CesA/Csl gene family has not been extensively studied in tea plants.Here,we identified 53 CsCesA/Csl genes in tea plants.These genes were grouped into five subfamilies(CsCesA,CsCslB,CsCslD,CsCslE,CsCslG)based on the phylogenetic relationships with Arabidopsis and rice.The analysis of chromosome distribution,gene structure,protein domain and motif revealed that most genes in CsCesA,CsCslD and CsCslE subfamilies were conserved,whereas CsCslB and CsCslG subfamily members are highly diverged.The transcriptome analysis showed that most CsCesA/Csl genes displayed tissue-specific expression pattern.In addition,members of CsCslB4,CsCesA1/3/6,CsCslB3/4,CsCslD3,CsCslE1 and CsCslG2/3 subfamilies were up-regulated under drought and cold stresses,indicating their potential roles in regulating stress tolerance in tea plants.Furthermore,the expression levels of CsCslG2_6 and CsCslD3_5 in different tissues and cultivars,respectively,were positively correlated with the cellulose content that is negatively related with shoot tenderness.Thus,these two genes were speculated to be involved in the regulation of shoot tenderness in tea plants.Our findings may help elucidate the evolutionary relationships and expression patterns of the CsCesA/Csl genes in tea plants,and provide more candidate genes responsible for stress tolerance and tenderness regulation in tea plants for future functional research. 展开更多
关键词 tea plant(camellia sinensis) cellulose synthase superfamily PHYLOGENY stress resistance shoot tenderness regulation
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In vitro anti-hyaluronidase activity of Sri Lankan low grown orthodox orange pekoe grade black tea(Camellia sinensis L.) 被引量:2
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作者 Wanigasekera Daya Ratnasooriya Walimuni Prabhashini Kaushalya Mendis Abeysekera Chatura Tissa Dayendra Ratnasooriya 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2014年第12期959-963,共5页
Objective:To access the anti-hyaluronidase activity of Sri Lankan low grown orthodox orange pekoe(OP) grade black tea with a view to develop an anti-aging skin formulation.Methods:Five concentrations(0.125,0.250,0.500... Objective:To access the anti-hyaluronidase activity of Sri Lankan low grown orthodox orange pekoe(OP) grade black tea with a view to develop an anti-aging skin formulation.Methods:Five concentrations(0.125,0.250,0.500,1.000 and 2.000 mg/mL) of black tea brew(BTB) were made using a freeze dried sample of Sri Lankan low grown orthodox OP grade black tea which was prepared according to international organization for standardization specification.Epigallocatechin gallate(EGCG) was used as the reference agent(concentrations tested:0.012,0.025,0.050,0.100 and 0.200 mg/mL).Anti-hyaluronidase activity of BTB and EGCG in vitro were ascertained spectrometrically using hyaluronic acid(from rooster comb)and bovine testicular hyaluronidase.Results:The results revealed that BTB had moderate[IC_(50)=(1.09±0.12) mg/mL]and dose dependent(r^2=0.94) anti-hyaluronidase activity.EGCG also exhibited dose dependent(r^2=0.93,P<0.05) anti-hyaluronidase activity which was superior[IC_(50)=(0.09±0.00) mg/mL]to BTB.Conclusions:Sri Lankan low grown orthodox OP gradc black tca has promising antihyaluronidase activity in vitro and has the potential to be used as an anti-aging cosmaceutical.In addition,it may prove useful as a beverage in the management of allergy,some joint diseases and cnvenomation. 展开更多
关键词 ORTHODOX EGCG ORANGE GALLATE specification camellia formulation moderate herbal ALLERGY
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Influence of Location of Production, Season and Genotype on Caffeine and Flavan-3-ols in Young Green Tea (Camellia sinensis) Leaves in Kenya 被引量:1
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作者 Bowa O. Kwachl Philip O. Owuor +2 位作者 David M. Kamau John K. Wanyoko Samson M. Kamunya 《Journal of Agricultural Science and Technology(B)》 2013年第8期557-574,共18页
关键词 生产区域 季节变化 茶叶品种 肯尼亚 咖啡因 地点 黄烷 茶树
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Preparation of high molecular weight (HMW) genomic DNA from tea plant (Camellia sinensis) for BAC library construction 被引量:1
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作者 LIN Jin-ke Dave Kudrna Rod A Wing 《Journal of Agricultural Science and Technology》 2009年第1期1-10,共10页
关键词 基因组DNA BAC文库 超高分子量 幼龄茶树 HMW C库 制备 细菌人工染色体
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Effect of Enriched Cattle Manure on Soil Nutrient Status, Nitrogen Uptake and Yield of Tea (Camellia sinensis)
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作者 Vivian Moroamoche Kekana Isaiah Tabu +1 位作者 David Kamau Robert Obura 《Journal of Agricultural Science and Technology(A)》 2014年第2期123-128,共6页
关键词 土壤养分状况 茶叶产量 氮素吸收 茶树 牛粪 无机肥料 富集 氮磷钾肥
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Functional Components of Tea(Camellia Sinensis)Germplasms Collected in Korea
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作者 Min-Seuk Lee Joo Yoo +1 位作者 Jin-Ho Lee Kwan Jeong Song 《茶叶》 2013年第4期199-200,共2页
This study was carried out to obtain useful information and to search quality related components for breeding of tea by analysis of Korean local tea leaves at Sulloc-Cha R&D center in Jeju Island,Korea.It was also... This study was carried out to obtain useful information and to search quality related components for breeding of tea by analysis of Korean local tea leaves at Sulloc-Cha R&D center in Jeju Island,Korea.It was also conducted to measure the major agronomic characteristics of 300 local germplasms.These results allowed us to select some superior lines as genetic resources for green-tea breeding and research genotypes. 展开更多
关键词 种质资源收集 茶树育种 功能组件 韩国 农艺性状 遗传资源 基因型
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Genetic Diversity Analysis of Wild Tea Plants in Yunnan Province Using EST-SSR Markers 被引量:4
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作者 Meng ZHOU Youyong LI +5 位作者 Xuemei SUN Jiajin WANG Jin XIE Hao CHENG Yungang WANG Benying LIU 《Agricultural Biotechnology》 CAS 2015年第1期9-15,共7页
In this study, 27 pairs of EST-SSR primers were employed to analyze the genetic diversity and genetic relationship of 100 wild tea plant germplasm re- sources and 22 cultivars, according to the results, a total of 88 ... In this study, 27 pairs of EST-SSR primers were employed to analyze the genetic diversity and genetic relationship of 100 wild tea plant germplasm re- sources and 22 cultivars, according to the results, a total of 88 polymorphic bands were amplified with 27 pairs of primers; the variation of effective alleles accounted for 69.01% ; a total of 183 genotypes were detected, with a variation range of 4 -11 ; averagely 6.78 genotypes were amplified with each primer pair; Shannon index (I) of 27 primer pairs ranged from 0.32 to I. 35, with an average of 0.88 ; the observed heterozygosity (0.52) was basically consistent with the expected het- erozygosity (0.52) ; the average polymorphism heterozygosity was 0.48, which was very close to 0.50 ; the average Nei's index was 0.51, which was higher than 0. 50 ; the average polymorphism information content (PIC) was 0.52, which was higher than 0.50, indicating high genetic diversity among wild tea germplasm resources in Yuunan Province. According to the clustering results, based on geographical origins and genetic backgrounds, 122 materials were clustered into 14 categories. Dendrogram based on Nei's genetic distance revealed complex genetic relationships among wild tea germplasm resources in Yunnan Province. This study provided certain reference for subsequent preservation, development and research of wild tea germplasm resources in China. 展开更多
关键词 tea plant[ camellia sinensis (L.) O. Kuntze] EST-SSR Genetic diversity Genetic relationship
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Antimicrobial activity of green tea extract against isolates of methicillin-resistant Staphylococcus aureus and multi-drug resistant Pseudomonas aeruginosa 被引量:8
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作者 Maksum Radji Rafael Adi Agustama +1 位作者 Berna Elya Conny Riana Tjampakasari 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2013年第8期663-667,共5页
Objective:To evaluate antibacterial activity of the Indonesian water soluble green tea extract,Camellia sinensis,against clinical isolates of methicillin-resistantStaphylococcus aureus (S.aureus)(MRSA)and multi-drug r... Objective:To evaluate antibacterial activity of the Indonesian water soluble green tea extract,Camellia sinensis,against clinical isolates of methicillin-resistantStaphylococcus aureus (S.aureus)(MRSA)and multi-drug resistant Pseudomonas aeruginosa(MDR-P.aeruginosa).Methods:Antimicrobial activity of green tea extract was determined by the disc diffusion method and the minimum inhibitory concentration(MIC)was determined by the twofold serial broth dilutions method.The tested bacteria using in this study were the standard strains and multi-drug resistant clinical isolates of S.aureus and P.aeruginosa,obtained from Laboratory of Clinical Microbiology,Faculty of Medicine,University of Indonesia.Results:The results showed that the inhibition zone diameter of green tea extracts forS.aureus ATCC 25923 and MRSA were(18.970依0.287)mm,and(19.130依0.250)mm respectively.While the inhibition zone diameter forP.aeruginosa ATCC 27853 and MDR-P.aeruginosawere(17.550依0.393)mm and(17.670依0.398)mm respectively.The MIC of green tea extracts againstS.aureus ATCC 25923 and MRSA were 400μg/mL and 400μg/mL,respectively,whereas the MIC for P.aeruginosa ATCC 27853 and MDR-P.aeruginosawere 800μg/mL,and 800μg/mL,respectively.Conclusions:Camellia sinensisleaves extract could be useful in combating emerging drug-resistance caused by MRSA andP.aeruginosa. 展开更多
关键词 camellia sinensis Green tea ANTIBACTERIAL activity MIC Multi-drug resistant bacteria
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Discrimination of Green,Oolong,and Black Teas by GC-MS Analysis of Characteristic Volatile Flavor Compounds 被引量:29
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作者 Susanne Baldermann Ziyin Yang +4 位作者 Tsuyoshi Katsuno Vo Anh Tu Nobuyuki Mase Yoriyuki Nakamura Naoharu Watanabe 《American Journal of Analytical Chemistry》 2014年第9期620-632,共13页
Tea is one of the most consumed beverages in the world and its quality is influenced by geographical origin and production methods. This study focuses on the volatile aroma components of 38 tea products from China, Ja... Tea is one of the most consumed beverages in the world and its quality is influenced by geographical origin and production methods. This study focuses on the volatile aroma components of 38 tea products from China, Japan, Indonesia, Sri-Lanka, and Chinese Taipei;among them 7 green teas, 13 oolong teas, and 18 black teas. The volatiles were extracted from the infusions using PorapakQ-resin, concentrated, and analyzed by gas chromatography-mass spectrometry. The components were identified by authentic reference compounds or preliminary based on their mass spectra. Different manufacturing processes yield different blends of aroma compounds. In general, the contents of total volatiles, aliphatics, aromatics, and terpenoids increased with the fermentation degree, whereas jasmine lactone and indole were the highest in oolong teas. Some particular manufacturing processes, for example, the use of tea leaves infested by the tea green leafhopper, lead to higher contents of volatiles in final products as in Oriental Beauty oolong tea. The relative peak areas determined for 82 volatiles were the basis for the statistical analysis and highlight the potential of multivariate analysis to distinguish tea samples of different categories. 展开更多
关键词 AROMA camellia sinensis FERMENTATION Clustering Analysis tea
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New Process for Extracting Oil and Starch from Tea Seeds 被引量:8
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作者 Jinzhong Jiang Cuijuan Ren Zibu Wang Changjiang Qian Yuxiao Shen Ya Yang 《Journal of Food Science and Engineering》 2013年第12期699-703,共5页
关键词 茶叶籽 工艺包 淀粉 取油 生产过程 天然产品 生产成本 茶籽油
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Nitrogen and Potassium Dynamics in Tea Cultivation as Influenced by Fertilizer Type and Application Rates 被引量:1
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作者 Kibet Sitienei Patrick G. Home +1 位作者 David M. Kamau John K. Wanyoko 《American Journal of Plant Sciences》 2013年第1期59-65,共7页
As the most important cultural practices for tea production, single effects of nitrogen (N) and potassium (K) fertilization on yield are well documented but their dynamics are poorly understood. It was necessary there... As the most important cultural practices for tea production, single effects of nitrogen (N) and potassium (K) fertilization on yield are well documented but their dynamics are poorly understood. It was necessary therefore to assess the dynamics of nitrogen and potassium in tea cultivation environment as influenced by fertilizer application rates. This objective led to a comprehensive field investigation in strongly acidic soils tea plots at Tea Research Foundation of Kenya, Kangaita substation in Kerugoya using clone TRFK 11-4 ina 3 × 3, N × K factorial RCB design. Treatments were nitrogen (0, 100 and 200 Kg N·ha-1·yr.-1) as urea and potassium (0, 40 and 80 Kg K2O·ha-1·yr.-1) as Muriate of potash (MoP) replicated thrice. Tea yield, plant biomass and plant nutrient concentrations were measured for calculation of plant nutrient uptake. Nutrients accumulated in the plants and removed from harvest were considered as nutrient loss, while fertilizer was considered as nutrient inputs gain to soil. In the interaction, there was no much difference between N-K treatments and crop N removal except mature and maintenance leaves, but there was a positive linear relationship between N applied and the yield of made tea and negative linear relationship between K applied and yield of made tea. The results from the study also showed that fertilizer inputs generally surpassed the crop nutrient demands (nutrient loss from harvest). 展开更多
关键词 camellia sinensis (L.) DYNAMICS cloneS Concentration NUTRIENT Removals
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Physicochemical Properties and Functional Compounds of Commercial Green Tea Seed Oil 被引量:2
20
作者 Jong-Bang Eun Anggi Hapsari Bipin Vidya 《茶叶》 2013年第4期333-337,共5页
Physicochemical properties of green tea seed oil including cold test,color,flash point,gravity,refraction index,moisture content,acid value,iodine value,unsaponifiable matter and saponification value were investigated... Physicochemical properties of green tea seed oil including cold test,color,flash point,gravity,refraction index,moisture content,acid value,iodine value,unsaponifiable matter and saponification value were investigated.Fatty acid composition and catechin content of the oil was determined by GC and HPLC analysis.The oil is stable at low temperature.High flash point(267.8 ± 5.1℃) showed the high thermal stability of green tea seed oil as well,which support for suitability to use as cooking oil.Specific gravity and refraction index of green tea seed oil was found as 0.913 and 1.4679,respectively.Color of the oil was measured as 99.7 ± 0.2 for lightness,1.9 ± 0.1 for greenness and 6.6 ± 0.1 for yellowness.Acid value(KOH mg/ml),iodine value,unsaponifiable matter(%) and saponification value of green tea seed oil were 0.21,104.1,0.11 and 215,respectively.Fatty acids compositions of green tea seed oil was found to be dominated by oleic acid(81.3%) and presence of minor amount of linoleic acid(4.8%),palmitic acid(4.6%),palmitoleic acid(3.3%),linolenic acid(3.2%) and stearic acid(1.0%).The presence of antioxidative compounds such as(-)-epicatechingallate(207.2 ± 0.2 g /g) and(-)-epigallocatechin gallate(99.5 ± 0.6 g/g) in the oil could enhance its shelf life during storage. 展开更多
关键词 理化性质 茶籽油 化合物 脂肪酸组成 没食子酸酯 商业 热稳定性 不皂化物
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