Tea Plant Camellia Sinensis Research Articles

Total phenolic-flavonoids contents, anti-leishmanial, antimicrobial and antioxidant potentials of Pakistani tea brands and tea plant Camellia sinensis

Total phenolic-flavonoids contents, anti-leishmanial, antimicrobial and antioxidant potentials of Pakistani tea brands and tea plant Camellia sinensis

Identification and Expression Analysis of the SBP-box Gene Family Related to Abiotic Stress in Tea Plant (Camellia sinensis (L.) O. Kuntze)

Identification and Expression Analysis of the SBP-box Gene Family Related to Abiotic Stress in Tea Plant (Camellia sinensis (L.) O. Kuntze)

Haplotype-resolved genome assembly provides insights into evolutionary history of the tea plant Camellia sinensis

Tea is an important global beverage crop and is largely clonally propagated. Despite previous studies on the species, its genetic and evolutionary history deserves further research. Here, we present a haplotype-resolved assembly of an Oolong tea cultivar, Tieguanyin. Analysis of allele-specific expression suggests a potential mechanism in response to mutation load during long-term clonal propagation. Population genomic analysis using 190 Camellia accessions uncovered independent evolutionary histories and parallel domestication in two widely cultivated varieties, var. sinensis and var. assamica. It also revealed extensive intra- and interspecific introgressions contributing to genetic diversity in modern cultivars. Strong signatures of selection were associated with biosynthetic and metabolic pathways that contribute to flavor characteristics as well as genes likely involved in the Green Revolution in the tea industry. Our results offer genetic and molecular insights into the evolutionary history of Camellia sinensis and provide genomic resources to further facilitate gene editing to enhance desirable traits in tea crops.

Beverages Containing Plant-Derived Polyphenols Inhibit Growth and Biofilm Formation of Streptococcus mutans and Children’s Supragingival Plaque Bacteria

Objectives: Polyphenols in edible berries and tea plant (Camellia sinensis) suppressed virulence factors of oral pathogens. We investigated if the commercially marketed plant polyphenols-containing beverages inhibited growth and biofilm formation of Streptococcus mutans and children’s dental plaque. Methods: Supragingival plaque collected from 16 children (7–11 years) were suspended in TSB for testing. Test beverages included 26 marketed packaged teas, ready-to-drink bottled raspberry flavored teas and cranberry juice cocktails with and without added sugars. Their effects on in vitro growth and biofilm formation of S. mutans and children’s plaque bacteria were determined after 24–48 h at 37 °C anaerobically in CDM with or without sucrose. Results: Brewed infusions from black, green and cinnamon or raspberry flavored teas bags inhibited growth and biofilm formation of children’s plaque bacteria. Compared to controls, bottled raspberry flavored teas and cranberry juice cocktails significantly inhibited growth and biofilm formation of test bacteria. Added sugar did not significantly impact the inhibition (p > 0.05). Biofilms formed in these beverages were loosely attached and easily dislodged from surfaces. Conclusions: Beverages rich in antimicrobial plant polyphenols reduce plaque adherence, may benefit oral health and are preferred over other sugary beverages. The concept of oral diseases prevention using natural foods/diet is innovative, practical and acceptable.

Characteristics of radionuclides in soil and tea plant (Camellia sinensis) in Hoa Binh, Vietnam

Characteristics of radionuclides in soil and tea plant (Camellia sinensis) in Hoa Binh, Vietnam

TeaAS: a comprehensive database for alternative splicing in tea plants (Camellia sinensis)

Alternative splicing (AS) increases the diversity of transcripts and proteins through the selection of different splice sites and plays an important role in the growth, development and stress tolerance of plants. With the release of the reference genome of the tea plant (Camellia sinensis) and the development of transcriptome sequencing, researchers have reported the existence of AS in tea plants. However, there is a lack of a platform, centered on different RNA-seq datasets, that provides comprehensive information on AS.To facilitate access to information on AS and reveal the molecular function of AS in tea plants, we established the first comprehensive AS database for tea plants (TeaAS, http://www.teaas.cn/index.php). In this study, 3.96 Tb reads from 66 different RNA-seq datasets were collected to identify AS events. TeaAS supports four methods of retrieval of AS information based on gene ID, gene name, annotation (non-redundant/Kyoto encyclopedia of genes and genomes/gene ontology annotation or chromosomal location) and RNA-seq data. It integrates data pertaining to genome annotation, type of AS event, transcript sequence, and isoforms expression levels from 66 RNA-seq datasets. The AS events resulting from different environmental conditions and that occurring in varied tissue types, and the expression levels of specific transcripts can be clearly identified through this online database. Moreover, it also provides two useful tools, Basic Local Alignment Search Tool and Generic Genome Browser, for sequence alignment and visualization of gene structure.The features of the TeaAS database make it a comprehensive AS bioinformatics platform for researchers, as well as a reference for studying AS events in woody crops. It could also be helpful for revealing the novel biological functions of AS in gene regulation in tea plants.

Identification, evolution, expression analysis of phospholipase D (PLD) gene family in tea (Camellia sinensis).

The online version contains supplementary material available at 10.1007/s12298-021-01007-0.

Effects of Plant Growth Regulators on Flower Abscission and Growth of Tea Plant Camellia sinensis (L.) O. Kuntze

The flowering of tea plant Camellia sinensis (L.) O. Kuntze consumes large amounts of water and nutrients and negatively affects the growth of tea plant. The effects of plant growth regulators, including ethephon, α-naphthalene acetic acid, salicylic acid, chlormequat, and paclobutrazol, were investigated on the abscission of flower buds and flowers on the tea plant. The occurrence of anthracnose Gloeosporium theae-sinesis Miyake and tea green leafhopper Empoasca onukii Matsuda on the tea plant were also investigated after exogenous application of these chemicals. Ethephon (at 800, 1200, and 1600 mg l−1), paclobutrazol (at 150, 300, and 600 mg l−1), and chlormequat (at 300 and 600 mg l−1) significantly promoted the abscission of flower buds and flowers and finally reduced the number of tea flowers in the tea plantations. These three compounds had almost no effect on the number of tea shoots. Moreover, paclobutrazol and chlormequat also suppressed the occurrence of anthracnose on the tea plant. Paclobutrazol and chlormequat induced the high catalase and peroxidase activities in the tea plant. In addition, the photosynthetic characteristics and biochemical components such as tea polyphenols in the tea plant leaves treated with plant growth regulators decreased significantly. There was a certain correlation between effects of ethephon and paclobutrazol on flower abscission and the expression of ACS and ETR. Overall, plant growth regulators could effectively reduce tea flowers and suppress anthracnose on the tea plant.

Genome-wide identification of SULTR genes in tea plant and analysis of their expression in response to sulfur and selenium.

Sulfur (S) is an essential macronutrient required by plants. Plants absorb and transport S through sulfate transporters (SULTRs). In this study, we cloned 8 SULTR genes (CsSULTR1;1/1;2/2;1/3;1/3;2/3;3/3;5/4;1) from tea plant (Camellia sinensis), all of which contain a typical sulfate transporter and antisigma factor antagonist (STAS) conserved domain. Phylogenetic tree analysis further divided the CsSULTRs into four main groups. Many cis-acting elements related to hormones and environmental stresses were found within the promoter sequence of CsSULTRs. Subcellular localization results showed that CsSULTR4;1 localized in the vacuolar membrane and that other CsSULTRs localized to the cellular membrane. The tissue-specific expression of the 8 CsSULTR genes showed different expression patterns during the active growing period and dormancy period. In particular, the expression of CsSULTR1;1 was highest in the roots, but that of CsSULTR1;2 was lowest in the dormancy period. The expression of CsSULTR1;1/1;2/2;1/3;2 was stimulated under different concentrations of selenium (Se) and S; moreover, CsSULTR1;2/2;1/3;3/3;5 was upregulated in response to different valences of Se.

Divergent DNA methylation contributes to duplicated gene evolution and chilling response in tea plants.

The tea plant (Camellia sinensis) is a thermophilic cash crop and contains a highly duplicated and repeat-rich genome. It is still unclear how DNA methylation regulates the evolution of duplicated genes and chilling stress in tea plants. We therefore generated a single-base-resolution DNA methylation map of tea plants under chilling stress. We found that, compared with other plants, the tea plant genome is highly methylated in all three sequence contexts, including CG, CHG and CHH (where H=A, T, or C), which is further proven to be correlated with its repeat content and genome size. We show that DNA methylation in the gene body negatively regulates the gene expression of tea plants, whereas non-CG methylation in the flanking region enables a positive regulation of gene expression. We demonstrate that transposable element-mediated methylation dynamics significantly drives the expression divergence of duplicated genes in tea plants. The DNA methylation and expression divergence of duplicated genes in the tea plant increases with evolutionary age and selective pressure. Moreover, we detect thousands of differentially methylated genes, some of which are functionally associated with chilling stress. We also experimentally reveal that DNA methyltransferase genes of tea plants are significantly downregulated, whereas demethylase genes are upregulated at the initial stage of chilling stress, which is in line with the significant loss of DNA methylation of three well-known cold-responsive genes at their promoter and gene body regions. Overall, our findings underscore the importance of DNA methylation regulation and offer new insights into duplicated gene evolution and chilling tolerance in tea plants.

Low temperature effects on carotenoids biosynthesis in the leaves of green and albino tea plant (Camellia sinensis (L.) O. Kuntze)

Tea plant (Camellia sinensis (L.) O. Kuntze) is one of the most important economic crops worldwide, and it has a positive effect on human health. The low temperature in late autumn and early/late spring cold often cause damage to the normal physiological activities of tea plant, thereby reducing the quality and yield of tea. As one of the essential pigment of higher plant, carotenoids play an important role in the physiological activities of higher plant. In addition, as an important precursor of tea aroma volatiles, carotenoids are the important factors involved in the formation of tea quality. In this study, the main carotenoids, lutein and β-carotene, in leaves of common green tea cultivar 'Longjing 43′ and albino tea cultivar 'White leaf No.1′ were detected after low temperature treatment at 4 ℃. The results showed that the contents of lutein and β-carotene in 'Longjing 43′ were higher than that in 'White leaf No.1′, respectively. The chlorophyll content in two tea cultivars decreased and was significant positive correlation with two kinds of carotenoid content at low temperature. Under low temperature, the genes related to the biosynthesis pathway of methylerythritol 4-phosphate (MEP) and carotenoids all showed varying degrees of response with the changes of lutein and β-carotene content. The relative expression levels of CsDXS1, CsPSY1 and CsCHXB were up-regulated and higher than other related genes. Expression analysis of carotenoids biosynthesis genes and its correlation with carotenoids accumulation confirmed the regulatory role of structural genes in tea plant at low temperature. Promoter prediction results showed that the CsDXR, CsHDS1 and CsCHXB contain low-temperature response element LTR. This study provides reference for further study on the dynamic changes of carotenoids during the growth of tea plant.

R2R3-MYB transcription factor family in tea plant (Camellia sinensis): Genome-wide characterization, phylogeny, chromosome location, structure and expression patterns

MYB transcription factors play essential roles in many biological processes and environmental stimuli. However, the functions of the MYB transcription factor family in tea plants have not been elucidated. Here, a total of 122 CsR2R3-MYB genes were identified from the chromosome level genome of tea plant (Camellia sinensis). The CsR2R3-MYB genes were phylogenetically classified into 25 groups. Results from the structure analysis of the gene, conserved motifs, and chromosomal distribution supported the relative conservation of the R2R3-MYB genes family in the tea plant. Synteny analysis indicated that 122, 34, and 112 CsR2R3-MYB genes were orthologous to Arabidopsis thaliana, Oryza sativa and C. sinensis var. ‘huangdan’ (HD), respectively. Tissue-specific expression showed that all CsR2R3-MYB genes had different expression patterns in the tea plant tissues, indicating that these genes may perform diverse functions. The expression patterns of representative R2R3-MYB genes and the regulatory network of the main anthocyanin components were analyzed, which suggested that CsMYB17 may played a key role in the regulation of cya-3-O-gal, del-3-O-gal, cya-3-O-glu and pel-3-O-glu. Results from the qRT-PCR validation of selected genes suggested that CsR2R3-MYB genes were induced in response to drought, cold, GA, and ABA treatments. Overall, this study provides comprehensive and systematic information for research on the function of R2R3-MYB genes in tea plants.

Analysis of inbreeding depression in the tea plant (Camellia sinensis) based on the self-compatible cultivar ‘Ziyan’

Most tea plants (Camellia sinensis) are considered self-incompatible (SI). It is difficult to identify self-compatible (SC) tea mutants through controlled hand-pollination. ‘Ziyan’ (ZY), a purple tea cultivar, was previously found to be SC by pedigree relationship reconstruction of its offspring using DNA markers. To assess the inbreeding depression in C. sinensis, in this study we identified 29 selfing progeny plants (SP) of ZY and compared their fitness traits and contents of secondary metabolites with the out-crossing progeny (OP, n = 38 plants) and the clonal mother ZY (n = 3 plants). The results showed that fitness traits, including root-collar diameter, matured leaf area, and fruit number of SP, were significantly lower than those of OP and ZY. Notably, the average fruit number of SP was only 9.0 % of ZY and 7.3 % of OP. The spring bud flush time of SP was also significantly later than the OP as indicated by the sprouting index on March 30th, 2020. However, the average content of anthocyanin of SP was 3.67 times that of OP. The total catechin and caffeine contents in SP were lower than those in OP and ZY, but less significantly. Together, the results indicated a strong inbreeding depression of fitness traits in the first selfing generation of ZY, while the impacts on secondary metabolites were not consistent. In addition, a possible homozygous lethal allele was found on LG03. The findings of this study have useful implications for inbred line-based breeding and researches in C. sinensis.

Transcriptomic responses to aluminum stress in tea plant leaves

Tea plant (Camellia sinensis) is a well-known Al-accumulating plant, showing a high level of aluminum (Al) tolerance. However, the molecular mechanisms of Al tolerance and accumulation are poorly understood. We carried out transcriptome analysis of tea plant leaves in response to three different Al levels (0, 1, 4 mM, for 7 days). In total, 794, 829 and 585 differentially expressed genes (DEGs) were obtained in 4 mM Al vs. 1 mM Al, 0 Al vs. 1 mM Al, and 4 mM Al vs. 0 Al comparisons, respectively. Analysis of genes related to polysaccharide and cell wall metabolism, detoxification of reactive oxygen species (ROS), cellular transport, and signal transduction were involved in the Al stress response. Furthermore, the transcription factors such as zinc finger, myeloblastosis (MYB), and WRKY played a critical role in transcriptional regulation of genes associated with Al resistance in tea plant. In addition, the genes involved in phenolics biosynthesis and decomposition were overwhelmingly upregulated in the leaves treated with either 0 Al and 4 mM Al stress, indicating they may play an important role in Al tolerance. These results will further help us to understand mechanisms of Al stress and tolerance in tea plants regulated at the transcriptional level.

Comparative chloroplast genomes: insights into the evolution of the chloroplast genome of Camellia sinensis and the phylogeny of Camellia

BackgroundChloroplast genome resources can provide useful information for the evolution of plant species. Tea plant (Camellia sinensis) is among the most economically valuable member of Camellia. Here, we determined the chloroplast genome of the first natural triploid Chinary type tea (‘Wuyi narcissus’ cultivar of Camellia sinensis var. sinensis, CWN) and conducted the genome comparison with the diploid Chinary type tea (Camellia sinensis var. sinensis, CSS) and two types of diploid Assamica type teas (Camellia sinensis var. assamica: Chinese Assamica type tea, CSA and Indian Assamica type tea, CIA). Further, the evolutionary mechanism of the chloroplast genome of Camellia sinensis and the relationships of Camellia species based on chloroplast genome were discussed.ResultsComparative analysis showed the evolutionary dynamics of chloroplast genome of Camellia sinensis were the repeats and insertion-deletions (indels), and distribution of the repeats, indels and substitutions were significantly correlated. Chinese tea and Indian tea had significant differences in the structural characteristic and the codon usage of the chloroplast genome. Analysis of sequence characterized amplified region (SCAR) using sequences of the intergenic spacers (trnE/trnT) showed none of 292 different Camellia sinensis cultivars had similar sequence characteristic to triploid CWN, but the other four Camellia species did. Estimations of the divergence time showed that CIA diverged from the common ancestor of two Assamica type teas about 6.2 Mya (CI: 4.4–8.1 Mya). CSS and CSA diverged to each other about 0.8 Mya (CI: 0.4–1.5 Mya). Moreover, phylogenetic clustering was not exactly consistent with the current taxonomy of Camellia.ConclusionsThe repeat-induced and indel-induced mutations were two important dynamics contributed to the diversification of the chloroplast genome in Camellia sinensis, which were not mutually exclusive. Chinese tea and Indian tea might have undergone different selection pressures. Chloroplast transfer occurred during the polyploid evolution in Camellia sinensis. In addition, our results supported the three different domestication origins of Chinary type tea, Chinese Assamica type tea and Indian Assamica type tea. And, the current classification of some Camellia species might need to be further discussed.

Construction of a DArT-seq marker–based genetic linkage map and identification of QTLs for yield in tea (Camellia sinensis (L.) O. Kuntze)

As the second most consumed non-alcoholic beverage, the tea plant (Camellia sinensis) has high economic value. Tea improvement efforts that largely target economic traits such as yield have traditionally relied on conventional breeding approaches. The tea plant’s perennial nature and its long generation time make conventional approaches time-consuming and labour-intensive. Biotechnology provides a complementary tool for accelerating tea improvement programmes through marker-assisted selection (MAS). Quantitative trait loci (QTLs) identified on linkage maps are an essential prerequisite to the implementation of MAS. QTL analysis was performed on yield data over 3 years (2010–2012) across two sites (Timbilil and Kangaita, in Kenya), based on two parental framework linkage maps arising from a population of 261 F1 progeny, derived from a reciprocal cross between GW Ejulu and TRFK 303/577. The maps contain 15 linkage groups each, this corresponds to the haploid chromosome number of tea (2n=2x=30). The total length of the parental maps was 1028.1 cM for GW Ejulu and 1026.6 cM for TRFK 303/577 with an average locus spacing of 5.5 cM and 5.4 cM, respectively. A total of 13 QTLs were identified over the three measurement years. The 13 QTLs had LOD values ranging from 1.98 to 7.24 and explained 3.4% to 12% of the phenotypic variation. The two sites had seven mutually detected QTLs.

Bacterial diversity in tea plant (Camellia sinensis) rhizosphere soil from Qinling Mountains and its relationship with environmental elements

The bacterial diversity in rhizosphere soil is closely associated with its environmental factors, such as, pH, moisture and organic contents. The aims of this study were to understand the bacterial diversity in tea plant Camellia sinensis rhizosphere soils and explore its relationship with major organic elements, water, and pH in tea plant rhizosphere soil. The tea plant rhizosphere soils were randomly collected from five locations at the south side of Qinling Mountains. The bacterial diversity in the soil was determined by high-throughput amplicon sequencing technology. The organic elements, pH and moisture in the soil were measured using traditional analysis methods. The correlations between bacterial diversity and environmental elements were analyzed by using the General Linear Model (GLM), Canonical Correspondence Analysis (CCA) and Spearman’s rank correlation coefficients methods. Acidobacteria, Actinobacteria, Bacteroidetes, Chloroflexi, Gemmatimonadetes, Planctomycetes, Proteobacteria and Verrucomicrobia were the dominant phyla in the soil samples. Water content, pH, organic carbon and total nitrogen were the environmental elements that had the greatest correlation with the bacterial diversity in the rhizosphere soil samples. Nitrogen had the greatest effect on the bacterial diversity at genus level. Carbon, potassium, water and pH were positively correlated with Pedobacter and Mucilaginibacter genera. The bacterial diversity in tea plant rhizosphere is closely associated with its environmental elements. The soil elements in tea plant rhizosphere could also be adjusted through the change of rhizobacteria diversity besides chemical fertilization.

‘Discovery’ of the tea plant Thea assamica (now, Camellia sinensis var. assamica) in the Indian territory in the 1830s

The tea plant (Camellia sinensis, Theaceae; previously Thea sinensis, Ternstrœmiaceae) is a highly sought-after beverage source today. In 2018 alone, c. 270 B L of tea was consumed throughout the world. Global recognition of green tea has enhanced majorly, especially in the later decades of the 20th century, because of the level of antioxidants (c. 450 mg of vitamin C equivalents) it includes, currently seen valuable in the general well-being of humans. In this article, I chronicle the events that steered the ‘discovery’ of Thea assamica (presently, C. sinensis var. assamica) in the wilderness of Upper Assam (the Ahôm country) and its commercial, large-scale production. William Griffith, who searched it and wrote on the T. assamica material growing in the Indian territory in the 1830s, examined the plant community in which the natural populations of T. assamica grew, in addition to writing on the soil and other related aspects vital for its large-scale cultivation. His notes shed light on an early understanding of the ‘ecosystem’ in which T. assamica grew in the wild. Griffith clarifies that they spread naturally along the river and creek beds in North-eastern India from the neighbouring Chinese territory over the last several hundreds of years. His remarks on the adaptations of the tea plant and other associated plants to specific soil types and on the top soil he found in tea-growing areas impress not only as remarkable but also as pioneering. His comments on the kinds of plants associated with the tea-plant populations and the general vegetation around the tea plant foreshadow the ecological concepts, ‘communities’ and ‘vegetation types’, which were recognized formally much later.

Genetic relationship analysis and molecular fingerprint identification of the tea germplasms from Guangxi Province, China.

The tea plant (Camellia sinensis) is an evergreen woody plant with a high economic value. Guangxi Province is adjacent to the origin center of the tea plant in southern China. It has abundant germplasm resources and is a historically important tea-producing province. However, there is little information about the genetic diversity, genetic introgression, and fingerprints of the tea germplasms from Guangxi Province. Here, we constructed a phylogenetic tree of 126 tea accessions from Guangxi Province using 20 SSR markers. This tree classified these tea accessions into three subgroups containing 19, 47, and 60 members, respectively. High genetic similarity was observed among the three subgroups, and the genetic diversity of the populations was ranked as follows: subgroup 3 > subgroup 2 > subgroup 1. Furthermore, we analyzed the genetic relationships among 168 tea accessions from Guangxi Province and neighboring provinces. The results of the population structure analysis were highly consistent with the clustering results, and genetic introgression was observed. We identified six SSRs as the core marker set, because they could sufficiently distinguish between all 126 tea accessions. The results provide a crucial theoretical basis for utilization and protection of tea germplasms from Guangxi Province, and will help improve the breeding and popularization of elite tea cultivars.

A Study Concerning the Black Sea Region Teas : Quality Parameters and the Possibility of Conversion to the New Products by R&D

The tea plant is one of the most consumed as beverages in the world’s oldest and widely which ranks second after water among non-alcoholic beverages. Our country is 7th in terms of agricultural areas allocated to tea plant (Camellia sinensis, (L)), and it is 5th in dry tea production in the World. Consuming so much tea has led scientists to investigate the effects of tea on health. These studies have shown that bioactive components in the tea have antimutagenic, anticarcinogenic, antibacterial, antiallergic and antioxidant properties. Tea is an important agricultural product in the Eastern Black Sea Region and employs approximately 22500 families. However, in our country, tea is consumed only as a beverage and as a small amount of by-products. The rich bioactive content of tea is too much to be underestimated. Also, considering the production of tea in our country, it is seen that it does not create enough added value and it does not one of the non-tea product's market. For this reason, the aim of this study is to introduce the quality of the regional teas and to evaluate the processability of the non-tea products other than drinking tea which is in the first place in the world and provide important employment for our people.