Phylogenomic analyses reveal reticulate evolution between Neomicrocalamus and Temochloa (Poaceae: Bambusoideae).

Neomicrocalamus and Temochloa are closely related to bamboo genera. However, when considered with newly discovered and morphologically similar material from China and Vietnam, the phylogenetic relationship among these three groups was ambiguous in the analyses based on DNA regions. Here, as a means of investigating the relationships among the three bamboo groups and exploring potential sources of genomic conflicts, we present a phylogenomic examination based on the whole plastome, single-nucleotide polymorphism (SNP), and single-copy nuclear (SCN) gene datasets. Three different phylogenetic hypotheses were found. The inconsistency is attributed to the combination of incomplete lineage sorting and introgression. The origin of newly discovered bamboos is from introgressive hybridization between Temochloa liliana (which contributed 80.7% of the genome) and Neomicrocalamus prainii (19.3%), indicating that the newly discovered bamboos are closer to T. liliana in genetics. The more similar morphology and closer distribution elevation also imply a closer relationship between Temochloa and newly discovered bamboos.

Kengiochloa, a new bamboo genus to accommodate the morphologically unique species, Pseudosasapubiflora (Poaceae).

Pseudosasa was confirmed as polyphyletic by recent phylogenetic analyses, with Chinese species of Pseudosasa distantly related to those from Japan. Among the Chinese species of Pseudosasa, Pseudosasapubiflora is a morphologically unique as well as taxonomically problematic species endemic to South China, of which the generic designation is still uncertain. Molecular analyses based on both plastid and nuclear genomic data demonstrated that this species is closest to the recently published genus Sinosasa. Morphologically, the two are somewhat similar to each other in flowering branches developing at the nodes of every order of branches, raceme-like units of inflorescence with 3-5 short spikelets, each spikelet with few florets including a rudimentary one at the apex, and each floret with 3 stamens and 2 stigmas. However, P.pubiflora is very different from Sinosasa species in many reproductive and vegetative characters, such as the morphology of paracladia (lateral spikelet "pedicels"), the absence or existence of pulvinus at the base of paracladia, the relative length of the upper glume and the lowest lemma, the shape of lodicules and primary culm buds, the branch complement, the morphology of nodes, culm leaves and dried foliage leaf blades, and the number of foliage leaves per ultimate branchlet. The morphological and molecular evidence warrants recognition of a new genus to accommodate this unique species, which is here named Kengiochloa. After consulting related literature and examination of herbarium specimens or specimen photos, a taxonomic revision of K.pubiflora and its synonyms was made, and it was confirmed that four names, viz. P.gracilis, Yushanialanshanensis, Arundinariatenuivagina and P.parilis, should be merged with K.pubiflora, while Indocalamuspallidiflorus and Acidosasapaucifolia are distinct species.

Sinosasagracilis (Poaceae, Bambusoideae), a new combination supported by morphological and phylogenetic evidence.

The results of phylogenetic analysis, based on the whole chloroplast genome and morphological study support the transfer of a long ignored bamboo species, Sasagracilis, to the recently established genus, Sinosasa, in this study. Morphologically, this species differs from all the other known Sinosasa species by having very short (2-3 mm) foliage leaf inner ligules, which is unusual in this genus. A revised description of its morphology and colour photos are also provided.

A Novel Elucidation for Synflorescences of Chinese Bamboos.

The objective of this work is to elucidate the flowering structures of Chinese bamboos applying the synflorescence concept. To keep in line with grasses, the bamboo synflorescence is defined as a whole culm or a whole branch terminating in an inflorescence. For the first time, the repetitive and fundamental unit of bamboo synflorescences is clearly identified and termed as the "basic flowering branch". The basic flowering branch could be considered as the most simplified synflorescence for a bamboo species. Applying the synflorescence concept, the pseudospikelet is interpreted as a sort of basic flowering branch rather than a spikelet. Consequently, the synflorescence development pattern is consistent throughout the whole family. This study also marks the first recognition of both pseudospikelets and true spikelet flowering branches within the same bamboo synflorescence, which is observed in the genera Brachystachyum, Semiarundinaria and Menstruocalamus.

Chimonobambusasangzhiensis (Poaceae, Bambusoideae), a new combination supported by morphological and molecular evidence.

This study elucidates the taxonomic position of Indosasasangzhiensis in considering whether it belongs to Indosasa or Chimonobambusa. Based on morphological and molecular phylogenetic evidence, our results explicitly indicated that I.sangzhiensis should be a member of Chimonobambusa, rather than Indosasa, and is a distinct species closely related to C.communis, C.opienensis and C.puberula. Thus, the new combination Chimonobambusasangzhiensis (B.M.Yang) N.H.Xia & Z.Y.Niu is made. A detailed description as well as two color plates of this species are also provided.

The floral morphology of four Chinese Bambusa species (Poaceae, Bambusoideae) previously described only from vegetative material.

Due to their specialised flowering biology where frequent or even annual flowering is uncommon, reproductive materials of bamboos are not always available, so hampering taxonomic interpretation and research into other aspects. Bambusacontracta, B.corniculata, B.cornigera and B.subtruncata were established only based on vegetative materials and flowering or fruiting material has been hitherto unknown. The floral morphology of these four species is described for the first time and, correspondingly, epitypes are designated to support a more complete interpretation of the species.

Gelidocalamus fengkaiensis (Poaceae: Bambusoideae), a new bamboo species from Guangdong, China, with an analysis of branch development in relation to flowering.

BACKGROUND: Bamboos, widely distributed in temperate and tropical Asia, Africa and America, refer to a group of special plants in Poaceae, Bambusoideae. China is rich in bamboo species. However, due to a long flowering cycle, the flowering habit and the flowering structure of many bamboo species are still not well understood. Here, we report a new bamboo species from Guangdong, China and an analysis of its interesting branch development in relation to flowering. RESULTS: This species is similar to G. stellatus, the type species, but differs in the characteristics of its lemma and palea, mid-culm branch complement, and culm-sheath ligules. The initial branches at a culm node do not apically develop flowering structures during a flowering episode; instead, these form on what appears to be specialized flowering branches. CONCLUSIONS: The results of morphological comparison support the recognition of Gelidocalamus fengkaiensis as a new species. And during a flowering episode, two branch types ('foliage branch' and 'flowering branch') can be distinguished in this species.

Schizostachyum dakrongense (Poaceae, Bambusoideae), a new species from Dakrong Nature Reserve, Vietnam.

Schizostachyum dakrongense is a new species of woody bamboo from Dakrong Nature Reserve, Quang Tri Province, central Vietnam. It is closely related to S. hainanense but differs by its pseudospikelets having terminal rachilla segments with ciliate margin and 6 bracts; culm sheath with the base of the outer margin having a slight projection below its point of attachment at the node, as well as sheath blades usually less than half as long as the culm sheath proper; and leaf blades pale-puberulent and sparsely pilosulous on the abaxial surface. The new species is described and illustrated here.

Involvement of Salicylic Acid in Anthracnose Infection in Tea Plants Revealed by Transcriptome Profiling.

Anthracnose is a major leaf disease in tea plant induced by Colletotrichum, which has led to substantial losses in yield and quality of tea. The molecular mechanism with regards to responses or resistance to anthracnose in tea remains unclear. A de novo transcriptome assembly dataset was generated from healthy and anthracnose-infected leaves on tea cultivars "Longjing-43" (LJ43) and "Zhenong-139" (ZN139), with 381.52 million pair-end reads, encompassing 47.78 billion bases. The unigenes were annotated versus Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), National Center for Biotechnology Information (NCBI) non-redundant protein sequences (Nr), evolutionary genealogy of genes: Non-supervised Orthologous Groups (eggNOG) and Swiss-prot. The number of differential expression genes (DEGs) detected between healthy and infected leaves was 1621 in LJ43 and 3089 in ZN139. The GO and KEGG enrichment analysis revealed that the DEGs were highly enriched in catalytic activity, oxidation-reduction, cell-wall reinforcement, plant hormone signal transduction and plant-pathogen interaction. Further studies by quantitative reverse transcriptase polymerase chain reaction (qRT-PCR) and high-performance liquid chromatography (HPLC) showed that expression of genes involved in endogenous salicylic acid biosynthesis and also accumulation of foliar salicylic acid are involved in the response of tea plant to anthracnose infection. This study firstly provided novel insight in salicylic acid acting as a key compound in the responses of tea plant to anthracnose disease. The transcriptome dataset in this study will facilitate to profile gene expression and metabolic networks associated with tea plant immunity against anthracnose.

Inhibitory Effects of (-)-Epigallocatechin-3-gallate on Esophageal Cancer.

There is epidemiological evidence showing that drinking green tea can lower the risk of esophageal cancer (EC). The effect is mainly attributed to tea polyphenols and their most abundant component, (-)-epigallocatechin-3-gallate (EGCG). The possible mechanisms of tumorigenesis inhibition of EGCG include its suppressive effects on cancer cell proliferation, angiogenesis, DNA methylation, metastasis and oxidant stress. EGCG modulates multiple signal transduction and metabolic signaling pathways involving in EC. A synergistic effect was also observed when EGCG was used in combination with other treatment methods.

Bioavailability of Tea Catechins and Its Improvement.

Many in vitro studies have shown that tea catechins had vevarious health beneficial effects. However, inconsistent results between in vitro and in vivo studies or between laboratory tests and epidemical studies are observed. Low bioavailability of tea catechins was an important factor leading to these inconsistencies. Research advances in bioavailability studies involving absorption and metabolic biotransformation of tea catechins were reviewed in the present paper. Related techniques for improving their bioavailability such as nanostructure-based drug delivery system, molecular modification, and co-administration of catechins with other bioactives were also discussed.

Association of Tea Consumption with Risk of Alzheimer's Disease and Anti-Beta-Amyloid Effects of Tea.

Neurodegenerative disease Alzheimer's disease (AD) is attracting growing concern because of an increasing patient population among the elderly. Tea consumption is considered a natural complementary therapy for neurodegenerative diseases. In this paper, epidemiological studies on the association between tea consumption and the reduced risk of AD are reviewed and the anti-amyloid effects of related bioactivities in tea are summarized. Future challenges regarding the role of tea in preventing AD are also discussed.

Food-grade Encapsulation Systems for (-)-Epigallocatechin Gallate.

(-)-Epigallocatechin gallate (EGCG) has attracted significant research interest due to its health-promoting effects such as antioxidation, anti-inflammation and anti-cancer activities. However, its instability and poor bioavailability have largely limited its efficacy and application. Food-grade materials such as proteins, carbohydrates and lipids show biodegradability, biocompatibility and biofunctionality properties. Food-grade encapsulation systems are usually used to improve the bioavailability of EGCG. In the present paper, we provide an overview of materials and techniques used in encapsulating EGCG, in which the adsorption mechanisms of food-grade systems during in vitro digestion are reviewed. Moreover, the potential challenges and future work using food-grade encapsulates for delivering EGCG are also discussed.