Time filter

Source Type

Tan L.-Q.,Chinese Academy of Agricultural Sciences | Tan L.-Q.,Sichuan Agricultural University | Wang L.-Y.,Chinese Academy of Agricultural Sciences | Wang L.-Y.,Key Laboratory of Tea Plant Biology and Resources Utilization | And 16 more authors.
Tree Genetics and Genomes | Year: 2016

Tea plant (Camellia sinensis) is a major beverage crop across the world. To uncover the genetic controls of agronomic traits and facilitate marker-assisted breeding (MAB) in tea plant, we constructed a saturated SSR-based linkage map using an F1 population derived from the crossing of ‘Longjin43’ × ‘Baihaozao’. A total of 483 SSR markers, consisting of 117 novel loci, 129 transferred from other tea plant maps, and 237 previously mapped, were successfully integrated into a new consensus map. The map has 15 linkage groups, covering 1226.2 cM in total with an average marker distance of 2.5 cM. The 126 markers in common enabled us to align this map to the reference genetic maps of tea plant. Phenotype data were collected in 2014 and 2015 for five traits: timing of spring bud flush (TBF), young shoot color (YSC), mature leaf length (MLL), mature leaf width (MLW), and leaf shape index (LSI, i.e., MLL/MLW). QTL analyses were performed for the five traits using the new consensus map and 15 QTLs were identified. The SSR markers, linkage map, and QTLs reported here are useful resources for future QTL mining, identification of causal genes, and MAB in tea plant. © 2016, Springer-Verlag Berlin Heidelberg.


Tan L.-Q.,Sichuan Agricultural University | Peng M.,Sichuan Agricultural University | Xu L.-Y.,Sichuan Agricultural University | Wang L.-Y.,Key Laboratory of Tea Plant Biology and Resources Utilization | And 6 more authors.
Tree Genetics and Genomes | Year: 2015

The improved clonal tea cultivars play a crucial role in the modern tea industry. In present study, we analyzed 128 elite clonal tea cultivars in China with 30 well-chosen simple sequence repeat (SSR) markers, aiming at (1) characterizing a set of DNA markers for unambiguously fingerprinting clonal tea cultivars and (2) confirming or identifying the parent-offspring (PO) relationships among them. The results showed that the markers are highly polymorphic among the tested cultivars with an average allele number of 10.4 per locus and an average polymorphic information content of 0.704. Robust fingerprinting power was demonstrated: It was possible to fully discriminate all 128 cultivars by a combination of four markers, and the overall possibility of finding two random individuals having the same genotypes across the 30 loci was estimated to be 4.8 × 10−33. Eight SSR loci were further recommended as a core marker set for fingerprinting the tea plant. Meanwhile, parentage analysis based on the fingerprint data revealed 47 pairs of putative PO relationships, among which 33 were in agreement with the known pedigree information, whereas the other 14 were newly identified in this study. The SSR markers and pedigree relationships reported here are valuable for tea cultivar identification and new breeding programs. © 2015, Springer-Verlag Berlin Heidelberg.


Tan L.Q.,Sichuan Agricultural University | Zhang C.C.,Chinese Academy of Agricultural Sciences | Qi G.N.,Sichuan Agricultural University | Wang L.Y.,Chinese Academy of Agricultural Sciences | And 8 more authors.
Genetics and Molecular Research | Year: 2015

Genetic maps are essential tools for quantitative trait locus analysis and marker-assisted selection breeding. In order to select parents that are highly heterozygous for genetic mapping, the heterozygosity (HS) of 24 tea cultivars (Camellia sinensis) was analyzed with 72 simple sequence repeat markers. In total, 359 alleles were obtained with an average of 4.99 per marker. The HSvaried greatly from 37.5 to 71.0% with an average of 51.3%. On average, tea cultivars from Fujian Province showed a higher level of heterozygosity (59.8%) than those from Zhejiang (48.5%) and Yunnan (44.5%), and the 12 national tea cultivars were generally more heterozygous than the 12 provincial cultivars. Unweighted pair-group analysis using the arithmetic average grouping divided the 24 cultivars into 2 groups that are consistent with the morphological classification. All dual combinations of the 24 cultivars were studied to calculate the percentage of mappable markers when using pseudo-testcross mapping strategy, and results showed that this value also varied greatly from 51.4 to 90.3%. The genetic relationships and HSdifferences among different cultivars were discussed, and tea cultivars with high HSwere recommended as cross parents for genetic mapping programs. ©FUNPEC-RP.


Wei K.,Chinese Academy of Agricultural Sciences | Wei K.,Key Laboratory of Tea Plant Biology and Resources Utilization | Wang L.,Chinese Academy of Agricultural Sciences | Wang L.,Key Laboratory of Tea Plant Biology and Resources Utilization | And 10 more authors.
PLoS ONE | Year: 2015

The ratio of dihydroxylated to trihydroxylated catechins (RDTC) is an important indicator of tea quality and biochemical marker for the study of genetic diversity. It is reported to be under genetic control but the underlying mechanism is not well understood. Flavonoid 3'- hydroxylase (F3'H) and flavonoid 3',5'-hydroxylase (F3'5'H) are key enzymes involved in the formation of dihydroxylated and trihydroxylated catechins. The transcriptome and HPLC analysis of tea samples from Longjing43 and Zhonghuang2 under control and shading treatment were performed to assess the F3'H and F3'5'H genes that might affect RDTC. A total of 74.7 million reads of mRNA seq (2×101bp) data were generated. After de novo assembly, 109,909 unigenes were obtained, and 39,982 of them were annotated using 7 public databases. Four key F3'H and F3'5'H genes (including CsF3'5'H1, CsF3'H1, CsF3'H2 and CsF3'H3) were identified to be closely correlated with RDTC. Shading treatment had little effect on RDTC, which was attributed to the stable expression of these key F3'H and F3'5'H genes. The correlation of the coexpression of four key genes and RDTC was further confirmed among 13 tea varieties by real time PCR and HPLC analysis. The coexpression of three F3'H genes and a F3'5'H gene may play a key role in affecting RDTC in Camellia sinensis. The current results may establish valuable foundation for further research about the mechanism controlling catechin composition in tea. © 2015 Wei et al.


Wang L.,Chinese Academy of Agricultural Sciences | Wang L.,National Center for Tea Plant Improvement | Wang X.,Chinese Academy of Agricultural Sciences | Wang X.,National Center for Tea Plant Improvement | And 9 more authors.
Scientia Horticulturae | Year: 2014

Tea plant (Camellia sinensis (L.) O. Kuntze) is an economically important woody crop with a currently unsequenced full genome, which limits the ability to perform functional genome studies. Next-generation Sequencing (NGS) technologies, such as RNA sequencing (RNA-seq), provide a powerful approach for quantifying the transcriptome. In this study, RNA-seq was conducted using the Roche 454 platform in tea new shoots, generating 612,014 high-quality reads with an average sequence length of 343 base pairs. After the de novo assembly, 60,479 unigenes consisting of 32,384 contigs and 28,095 singletons were detected, including 10,141 novel genes which showed no homology with reported Camellia sinensis sequences. To investigate the large-scale gene expression in different tea plant clones, a custom oligonucleotide microarray was developed using sequences from the RNA-seq study to design the probes because a commercial array is unavailable for the tea plant. A 4. ×. 44. K 60-mer oligo microarray consisting of 43,833 probes covering 42,440 unigene sequences and 1417 positive and negative Agilent control sequences was designed and used to analyze the expression profiles of four tea plant clones. The microarray data demonstrated that the dataset can be used for typical analyses, including principal component analysis (PCA) and differential gene expression analysis. The PCA showed that the four genotypes were differentiated from each other with good biological repeatability. To investigate the mechanism of higher amino acid content in 'Zhongcha 108', 'Zhonghuang 1' and 'Zhonghuang 2', genes involved in amino acid metabolism were analyzed and significant differential expression of a number of these genes was seen in the three cultivars compared to 'Longjing 43'. Twenty differentially expressed genes were validated by qRT-PCR, and the qRT-PCR results displayed a similar tendency in variation as the microarray results. We have developed a tea plant oligonucleotide microarray that can be used to analyze gene expression in the shoots of different tea plant clones without prior sequence knowledge. The combination of RNA-seq and custom microarray design was shown to be a powerful method for identifying differential expression genes among different tea cultivars. © 2014 Elsevier B.V.

Loading Key Laboratory of Tea Plant Biology and Resources Utilization collaborators
Loading Key Laboratory of Tea Plant Biology and Resources Utilization collaborators