Accumulation mechanism of metabolite markers identified by machine learning between Qingyuan and Xiushui counties in Polygonatum cyrtonema Hua.

Polygonatum cyrtonema Hua is a traditional Chinese medicinal plant acclaimed for its therapeutic potential in diabetes and various chronic diseases. Its rhizomes are the main functional parts rich in secondary metabolites, such as flavonoids and saponins. But their quality varies by region, posing challenges for industrial and medicinal application of P. cyrtonema. In this study, 482 metabolites were identified in P. cyrtonema rhizome from Qingyuan and Xiushui counties. Cluster analysis showed that samples between these two regions had distinct secondary metabolite profiles. Machine learning methods, specifically support vector machine-recursive feature elimination and random forest, were utilized to further identify metabolite markers including flavonoids, phenolic acids, and lignans. Comparative transcriptomics and weighted gene co-expression analysis were performed to uncover potential candidate genes including CHI, UGT1, and PcOMT10/11/12/13 associated with these compounds. Functional assays using tobacco transient expression system revealed that PcOMT10/11/12/13 indeed impacted metabolic fluxes of the phenylpropanoid pathway and phenylpropanoid-related metabolites such as chrysoeriol-6,8-di-C-glucoside, syringaresinol-4'-O-glucopyranosid, and 1-O-Sinapoyl-D-glucose. These findings identified metabolite markers between these two regions and provided valuable genetic insights for engineering the biosynthesis of these compounds.

Effects of Rhythm Control for Atrial Fibrillation on Cardiac Remodeling and Valvular Regurgitation in Patients with Heart Failure.

PURPOSE: Previous studies investigating cardiac remodeling and functional regurgitation of rhythm control for atrial fibrillation (AF) in heart failure (HF) are limited. Therefore, this study aimed to evaluate the impact of rhythm control for AF on cardiac remodeling and functional regurgitation in the spectrum of HF. Its effect on prognosis was explored. METHODS: According to the treatment strategies of AF, the cohort was classified into the rhythm control and rate control groups. To further detect the implications of rhythm control on cardiac remodeling, functional regurgitation, and outcomes in HF subtypes, patients were further divided into HF with reduced ejection fraction (HFrEF), HF with mildly reduced ejection fraction, and HF with preserved ejection fraction (HFpEF) subgroups. RESULTS: A total of 828 patients were enrolled, with 307 patients in the rhythm control group and 521 patients in the rate control group. Over a median follow-up time of 3.8 years, patients with rhythm control treatments experienced improvements in biatrial structure parameters, left ventricular ejection fraction, and functional regurgitation (mitral and tricuspid regurgitation) compared with rate control treatment (p < 0.05). Cox regression analysis demonstrated that rhythm control reduced the risks of all-cause mortality (HR 0.436 [95% CI, 0.218-0.871], p = 0.019) in HFpEF and HF-related admissions in HFrEF (HR 0.500 [95% CI, 0.330-0.757], p = 0.001) and HFpEF (HR 0.541 [95% CI, 0.407-0.720], p < 0.001); these associations were similar after adjusting for multiple confounders. CONCLUSIONS: Rhythm control therapy can be considered an appropriate treatment strategy for the management of AF in HF to improve cardiac remodeling, functional regurgitation, and prognosis.

Hormonal and Metabolomic Responses of Dendrobium catenatum to Infection with the Southern Blight Pathogen Sclerotium delphinii.

Southern blight caused by Sclerotium delphinii has a devastating effect on Dendrobium catenatum (an extremely valuable medicinal and food homologous Orchidaceae plant). However, the mechanisms underlying S. delphinii infection and D. catenatum response are far from known. Here, we investigated the infection process and mode of S. delphinii through microscopic observations of detached leaves and living plantlets and further explored the hormonal and metabolomic responses of D. catenatum during S. delphinii infection by using the widely targeted metabolome method. The results showed that S. delphinii infection involves two stages: a contact phase (12 to 16 h after inoculation) and a penetration stage (20 h after inoculation). S. delphinii hyphae could penetrate leaves directly (via swollen hyphae and the formation of an infection cushion) or indirectly (via stomatal penetration), causing water-soaked lesions on leaves within 24 to 28 h after inoculation and expanded thereafter. The content of jasmonates increased after the hyphal contact and remained at high levels during S. delphinii infection, whereas the ethylene precursor (1-aminocyclopropanecarboxylic acid) accumulated significantly after penetration. Furthermore, metabolites of the phenylpropanoid and flavonoid pathways were enriched after pathogen penetration, whereas several amino acids accumulated in significant amounts at the late stage of infection. Moreover, some other associated metabolites were significantly altered during pathogen infection. Therefore, the jasmonate, phenylpropanoid, flavonoid, and amino acid pathways could play crucial roles in D. catenatum resistance to S. delphinii infection. This study provides insight into the prevention and control of southern blight disease of D. catenatum.

Functional analysis of WOX family genes in Dendrobium catenatum during growth and development.

The WUSCHEL-Related Homeobox (WOX) family is a group of transcription factors unique to plants that play an important role in regulating key developmental processes such as stem cell maintenance and organ morphogenesis. As a rare and valuable Chinese herb, Dendrobium catenatum has a unique epiphytic lifestyle and growth and developmental characteristics, and a functional investigation of its WOX family genes can help to further understand the conserved and specific development of D. catenatum. In this study, we analyzed the phylogeny, spatio-temporal expression pattern and heterologous expression function of D. catenatum WOX family genes (DcWOX). The results showed that members of the D. catenatum WOX gene family could be divided into three evolutionary branches with significantly different tissue expression profiles. In transgenic Arabidopsis, overexpression of DcWOX4 resulted in significant dwarfism, pinnately leaf margins, and delayed flowering for 2 weeks; overexpression of DcWOX9 resulted in plant dwarfing, serrated leaf margin, delayed flowering for 1 week, and even male and female sterility in strong phenotype plants; overexpression of DcWOX11 caused curl downward leaf. The abnormal morphogenesis of DcWOX4/9/11 overexpression Arabidopsis leaves are related to the down-regulation of TCP family genes, CUC family genes and the up-regulation of KNOX family genes; Postponement of flowering is related to down-regulation of early flowering genes such as FT, SOC1 and CO. Therefore, this study showed that D. catenatum WOX family genes have important functions in regulating plant morphogenesis, leaf development, flowering time and fertility, further expanding the understanding of the WOX gene family function, and providing clues for the conservation and specificity during orchid development and evolution.

[Inhibitory effect of three strains of biocontrol microbes on pathogens causing rhizome rot of Polygonatum cyrtonema].

Rhizome rot is one of the main disease in the cultivation of Polygonatum cyrtonema, and it is also a global disease which seriously occurs on the perennial medicinal plants such as Panax notoginseng and P. ginseng. There is no effective control method at present. To identify the effects of three biocontrol microbes(Penicillium oxalicum QZ8, Trichoderma asperellum QZ2, and Brevibacillus amyloliquefaciens WK1) on the pathogens causing rhizome rot of P. cyrtonema, this study verified six suspected pathogens for their pathogenicity on P. cyrtonema. The result showed that Fusarium sp. HJ4, Colletotrichum sp. HJ4-1, and Phomopsis sp. HJ15 were the pathogens of rhizome rot of P. cyrtonema, and it was found for the first time that Phomopsis sp. could cause rhizome rot P. cyrtonema. Furthermore, the inhibitory effects of biocontrol microbes and their secondary metabolites on three pathogens were determined by confrontation culture. The results showed that the three tested biocontrol microbes significantly inhibited the growth of three pathogens. Moreover, the secondary metabolites of T. asperellum QZ2 and B. amyloliquefaciens WK1 showed significant inhibition against the three pathogens(P<0.05), and the effect of B. amyloliquefaciens WK1 sterile filtrate was significantly higher than that of high tempe-rature sterilized filtrate(P<0.05). B. amyloliquefaciens WK1 produced antibacterial metabolites to inhibit the growth of pathogens, and the growth inhibition rate of its sterile filtrate against three pathogens ranged from 87.84% to 93.14%. T. asperellum QZ2 inhibited the growth of pathogens through competition and antagonism, and P. oxalicum QZ8 exerted the inhibitory effect through competition. The research provides new ideas for the prevention and treatment of rhizome rot of P. cyrtonema and provides a basis for the di-sease control in other crops.

Effect of cultivation mode on bacterial and fungal communities of Dendrobium catenatum.

BACKGROUND: The orchid growth and development often associate with microbes. However, the interaction between plant performance and microbial communities within and surrounding plants is less understood. Dendrobium catenatum, which used to be an endangered orchid species, has become a billion dollar industry in China. Simulated natural cultivation modes, such as living tree epiphytic (LT) and cliff epiphytic (CE) cultivations, improve the production or quality of D. catenatum and contribute to the development of D. catenatum industry. In a previous study, morphological characteristics, anatomical structure, and main bioactive components (polysaccharides and ethanol-soluble extractives) of D. catenatum grown under LT and CE significantly differed from a facility cultivation mode, pot (PO) cultivation, were observed. Whether cultivation mode affects bacterial and fungal communities of D. catenatum, thereby affecting the chemical quality of this plant, need to be explored. RESULTS: Both three plant organs (leaf, stem, and root) and cultivating substrates obtained under three cultivation modes: living tree epiphytic (LT), cliff epiphytic (CE), and pot (PO) cultivation were examined by adopting high-throughput sequencing methods. Subsequently, bacterial and fungal correlations with D. catenatum main chemical components, stem polysaccharides and ethanol-soluble extractives and leaf phenols and flavonoids, were elucidated. The results showed that microbial communities of the plants and substrates are both influenced by the cultivation mode. However, the plants and their cultivating substrates exhibited different patterns of bacterial and fungal composition, with clearly distinguished dominant bacterial groups, but shared dominance among fungal groups. Bacteria and fungi differed in abundance, diversity, and community structure, depending on the cultivation environment and plant organ. Both bacterial and fungal communities were affected by cultivation mode and plant organ. In both plants and substrates, PO bacterial and fungal community structure differed significantly from those of LT and CE modes. Bacterial and fungal community structure differed significantly between roots and the other two plant organs examined (stems and leaves). Several bacteria and fungi were positively correlated with main chemical components in D. catenatum. CONCLUSIONS: The findings indicate that microbial communities of the plants and substrates were both influenced by the cultivation mode and plant organ, and some of them were positively correlated with main chemical components in D. catenatum. The research would enhance our understanding of interactions between Dendrobium and the microbial environment, and to provide a theoretical basis for the development of improved D. catenatum cultivation methods.

Out of the Himalaya-Hengduan Mountains: Phylogenomics, biogeography and diversification of Polygonatum Mill. (Asparagaceae) in the Northern Hemisphere.

Clarifying the process of formation of diversity hotspots and the biogeographic connection between regions is critical in understanding the impact of environmental changes on organismal evolution. Polygonatum (Asparagaceae) is distributed across the Northern Hemisphere. It displays an uneven distribution, with more than 50% of its species occurring in the Himalaya-Hengduan Mountains (HHM). Here, we generated a time-calibrated phylogeny of Polygonatum, based on whole-plastome data, to reconstruct the genus' biogeographical history and morphological/chromosomal evolution. Our phylogenetic analyses strongly support the monophyly of Polygonatum and its division into three sections (i.e., Verticillata, Sibirica, and Polygonatum). Polygonatum originated from the HHM region during the early-Miocene (c. 20.10 Ma), and began to radiate since the mid-Miocene, driven by the uplift of the Qinghai-Tibet Plateau (QTP), increasingly colder/arid climates following the mid-Miocene Climatic Optimum (MMCO), and intensification of the East Asian winter monsoon. Dispersal from the HHM region to other regions was facilitated by the intensification of East Asian summer monsoon in response to global climatic warming during the MMCO. Decreasing dysploidy accompanied by karyotype change and polyploidization in Polygonatum appears to be associated with its diversification and colonization of new ecological niches. Our results highlight the importance of regional tectonic activities and past climatic changes from the Neogene onwards to the spatial-temporal diversification and distribution patterns of plant lineages with a wide distribution in the Northern Hemisphere. They also contribute to the knowledge of the uneven species richness between East Asia and other regions.

Action Mechanisms of Effectors in Plant-Pathogen Interaction.

Plant pathogens are one of the main factors hindering the breeding of cash crops. Pathogens, including oomycetes, fungus, and bacteria, secrete effectors as invasion weapons to successfully invade and propagate in host plants. Here, we review recent advances made in the field of plant-pathogen interaction models and the action mechanisms of phytopathogenic effectors. The review illustrates how effectors from different species use similar and distinct strategies to infect host plants. We classify the main action mechanisms of effectors in plant-pathogen interactions according to the infestation process: targeting physical barriers for disruption, creating conditions conducive to infestation, protecting or masking themselves, interfering with host cell physiological activity, and manipulating plant downstream immune responses. The investigation of the functioning of plant pathogen effectors contributes to improved understanding of the molecular mechanisms of plant-pathogen interactions. This understanding has important theoretical value and is of practical significance in plant pathology and disease resistance genetics and breeding.

Jasmonate Signaling Pathway Modulates Plant Defense, Growth, and Their Trade-Offs.

Lipid-derived jasmonates (JAs) play a crucial role in a variety of plant development and defense mechanisms. In recent years, significant progress has been made toward understanding the JA signaling pathway. In this review, we discuss JA biosynthesis, as well as its core signaling pathway, termination mechanisms, and the evolutionary origin of JA signaling. JA regulates not only plant regeneration, reproductive growth, and vegetative growth but also the responses of plants to stresses, including pathogen as well as virus infection, herbivore attack, and abiotic stresses. We also focus on the JA signaling pathway, considering its crosstalk with the gibberellin (GA), auxin, and phytochrome signaling pathways for mediation of the trade-offs between growth and defense. In summary, JA signals regulate multiple outputs of plant defense and growth and act to balance growth and defense in order to adapt to complex environments.

[Relative molecular mass distribution and monosaccharide composition of polysaccharides in Polygonatum kingianum var.grandifolium].

Polygonatum kingianum var.grandifolium, different from most Polygonatum species in biological characteristics, sprouts and blooms in spring and autumn, respectively, and it is evergreen in winter.It is difficult to learn from the patterns of other Polygonatum plants because the chemical composition in P.kingianum var.grandifolium changes with phenology, which consequently restricts the production of high-quality medicinal and eatable substances.Samples of P.kingianum var.grandifolium in different months and ages collected from Xiushan, Chongqing were analyzed for polysaccharide content, polysaccharide relative molecular mass, and mono-saccharide composition by anthrone-sulfuric acid colorimetric assay, high-performance gel-permeation chromatography, and trimethylsilane(TMS) derivatization prior to GC-MS.The results showed that the polysaccharide content and composition in the rhizome of P.kingianum var.grandifolium were closely related to the growth period.New shoot sprouting promoted the accumulation of polysaccharides, and flowering and fruiting consumed polysaccharides.The highest polysaccharide content was found in April, reaching 134.04 mg·g~(-1).Polysaccharides in P.kingianum var.grandifolium were divided into five fractions according to the weight-average M_W, i.e., P1(2.02×10~7), P2(5.09×10~6), P3(1.37×10~6), P4(4.73×10~5), and P5(5.11×10~3), and P5 had the highest content.In terms of monosaccharide composition, polysaccharides were mainly composed of fructose, glucose, galactose, mannose, xylose, and arabinose with the average molar ratio of 1.31∶1.00∶0.90∶0.53∶0.22∶0.21.The results of the study provide a scientific basis for the precise harvesting and resource utilization of P.kingianum var.grandifolium.

JA signal-mediated immunity of Dendrobium catenatum to necrotrophic Southern Blight pathogen.

BACKGROUND: Dendrobium catenatum belongs to the Orchidaceae, and is a precious Chinese herbal medicine. In the past 20 years, D. catenatum industry has developed from an endangered medicinal plant to multi-billion dollar grade industry. The necrotrophic pathogen Sclerotium delphinii has a devastating effection on over 500 plant species, especially resulting in widespread infection and severe yield loss in the process of large-scale cultivation of D. catenatum. It has been widely reported that Jasmonate (JA) is involved in plant immunity to pathogens, but the mechanisms of JA-induced plant resistance to S. delphinii are unclear. RESULTS: In the present study, the role of JA in enhancing D. catenatum resistance to S. delphinii was investigated. We identified 2 COI1, 13 JAZ, and 12 MYC proteins in D. catenatum genome. Subsequently, systematic analyses containing phylogenetic relationship, gene structure, protein domain, and motif architecture of core JA pathway proteins were conducted in D. catenatum and the newly characterized homologs from its closely related orchid species Phalaenopsis equestris and Apostasia shenzhenica, along with the well-investigated homologs from Arabidopsis thaliana and Oryza sativa. Public RNA-seq data were investigated to analyze the expression patterns of D. catenatum core JA pathway genes in various tissues and organs. Transcriptome analysis of MeJA and S. delphinii treatment showed exogenous MeJA changed most of the expression of the above genes, and several key members, including DcJAZ1/2/5 and DcMYC2b, are involved in enhancing defense ability to S. delphinii in D. catenatum. CONCLUSIONS: The findings indicate exogenous MeJA treatment affects the expression level of DcJAZ1/2/5 and DcMYC2b, thereby enhancing D. catenatum resistance to S. delphinii. This research would be helpful for future functional identification of core JA pathway genes involved in breeding for disease resistance in D. catenatum.

[Effects of different storage conditions on edible quality and antioxidant activity of Polygonatum cyrtonema flowers].

The flower of Polygonatum cyrtonema has good edible and medicinal values. In this study, four samples of P. cyrtonema flowers from different regions were selected as test materials. The contents, composition and antioxidant activities of lipid-soluble pigments and alcohol-soluble components were determined under different light and temperature conditions, which help to reveal the discoloration reason and the composition variation patterns during storage. The results showed that light and temperature had different effects on the lipid-soluble pigments and alcohol-soluble components in the dried flowers during storage. After storage for 4 weeks, the contents of total chlorophyll, carotenoids, phenols and saponins in the samples exposed to light respectively decreased by 62.62%, 66.4%, 68.7% and 43.4% compared with those in the dark. The decreases in the contents of chlorophyll a, chlorophyll b, lutein, ß-carotene and zeaxanthin were 64.64%, 56.74%, 59.2%, 77.7% and 45.4%, respectively. The contents of pigments and components in the samples stored at-20 ℃ were significantly higher than those at room temperature and 4 ℃, indicating that low temperature was conductive to the stability of lipid-soluble pigments and alcohol-soluble components. The samples stored at low temperature and in the dark had the strongest free radical scavenging activity. The results suggest that P. cyrtonema dried flowers should be stored in low temperature environment without light, which can slow down the degradation of internal components. The study provides a theoretical basis for the production, processing and storage of P. cyrtonema flowers.

[Quality evaluation of Polygonatum cyrtonema based on HPLC fingerprint and multi-component quantitative analysis].

The medicinal and edible Polygonatum cyrtonema is one of the original species of Polygonati Rhizoma. In this study,HPLC fingerprints for 25 batches of P. cyrtonema from 6 provinces were established. A total of 14 common peaks were identified and the similarities of the fingerprints were in the range of 0. 939-0. 999. In additon, the partial least squares-discriminant analysis(PLSDA) demonstrated that the samples had low discriminability except for JX-1 and most components of them had no significant correlation with environmental factors such as longitude, latitude, and altitude. Thus, chemical composition specificity of P. cyrtonema in natural distribution areas had no obvious regularity and their variation might be induced by the local environment. This conclusion explained the lack of records about Dao-di area of Polygonati Rhizoma. However, JX-1 boasted significantly higher content of 5-hydroxymethylfurfural(HMF) and 4',5,7-trihydroxy-6,8-dimethylhomoisoflavone( HIF), thick and long inflorescence and rhizome, and extremely high yield. Therefore, excellent variety of P. cyrtonema might have great potential to improve the quality and yield of Polygonati Rhizoma. Moreover, three components of HMF, polygonalline A(PA), and HIF were identified in the fingerprint. Among them, HMF has the activities of blood rheology improvement, antioxidation, and anti-myocardial ischemia and PA is an indolizine alkaloid with potential anti-inflammatory activity. HIF, the characteristic homoisoflavone in Polygonatum, has the pharmacological activities of regulating blood glucose and anti-tumor. A quantitative analysis method can provide a theoretical basis for the improvement of the quality evaluation of Polygonati Rhizoma.

[Investigation on reproductive characteristics of Polygonatum cyrtonema].

The study is aimed to investigate the reproductive biology characteristics of Polygonatum cyrtonema, especially including phenology, flower bud differentiation, flowering timing, floral traits, pollen vigor and stigma receptivity. The results showed that P. cyrtonema forms inflorescence before the leaves spread. In the wild, P. cyrtonema is mainly pollinated by insects such as bumblebees, with a seed setting rate of 65.12%. The seed setting rate of indoor single plant isolation or self-pollination enclosed by parchment paper bag is 0, indicating that it is self-incompatible. In Lin'an city, seedlings begin to emerge from mid-March to early April(the temperature is higher than 7.5 ℃), buds begin to emerge from the end of March to mid-April, and then undergo the full bloom stage from mid-to-late April, and the final flowering stage from the end of April to mid-May. The whole flowering period lasts 36 to 45 days. There are obvious differences in the phenology of different provenances. The flowers come into bloom from the base to the top along the aboveground main axis, which usually contain 4-22 inflorescences with(2-) 4-10(-21) flowers per inflorescence. The flowering pe-riod for a single plant is 26-38 days. The single flower lasts about 20-25 days from budding to opening and withers 2 days after pollination, and then the ovary will gradually expand. If unpollinated, it will continue to bloom for 3-5 days and then wither. Flower development period is significantly related to pollen vigor and stigma remittance. The pollen viability is the highest when the flower is fully opened with anthers gathering on the stigma, and the receptivity is the strongest when the stigma protrudes out of the perianth and secretes mucus. The fruits and seeds ripen in October, and proper shading can ensure the smooth development and maturity of the seeds. This study provides a basis for the hybrid breeding and seed production of P. cyrtonema.

Genome-wide identification and expression profiling of SET DOMAIN GROUP family in Dendrobium catenatum.

BACKGROUND: Dendrobium catenatum, as a precious Chinese herbal medicine, is an epiphytic orchid plant, which grows on the trunks and cliffs and often faces up to diverse environmental stresses. SET DOMAIN GROUP (SDG) proteins act as histone lysine methyltransferases, which are involved in pleiotropic developmental events and stress responses through modifying chromatin structure and regulating gene transcription, but their roles in D. catenatum are unknown. RESULTS: In this study, we identified 44 SDG proteins from D. catenatum genome. Subsequently, comprehensive analyses related to gene structure, protein domain organization, and phylogenetic relationship were performed to evaluate these D. catenatum SDG (DcSDG) proteins, along with the well-investigated homologs from the model plants Arabidopsis thaliana and Oryza sativa as well as the newly characterized 42 SDG proteins from a closely related orchid plant Phalaenopsis equestris. We showed DcSDG proteins can be grouped into eight distinct classes (I~VII and M), mostly consistent with the previous description. Based on the catalytic substrates of the reported SDG members mainly in Arabidopsis, Class I (E(z)-Like) is predicted to account for the deposition of H3K27me2/3, Class II (Ash-like) for H3K36me, Class III (Trx/ATX-like) for H3K4me2/3, Class M (ATXR3/7) for H3K4me, Class IV (Su (var)-like) for H3K27me1, Class V (Suv-like) for H3K9me, as well as class VI (S-ET) and class VII (RBCMT) for methylation of both histone and non-histone proteins. RNA-seq derived expression profiling showed that DcSDG proteins usually displayed wide but distinguished expressions in different tissues and organs. Finally, environmental stresses examination showed the expressions of DcASHR3, DcSUVR3, DcATXR4, DcATXR5b, and DcSDG49 are closely associated with drought-recovery treatment, the expression of DcSUVH5a, DcATXR5a and DcSUVR14a are significantly influenced by low temperature, and even 61% DcSDG genes are in response to heat shock. CONCLUSIONS: This study systematically identifies and classifies SDG genes in orchid plant D. catenatum, indicates their functional divergence during the evolution, and discovers their broad roles in the developmental programs and stress responses. These results provide constructive clues for further functional investigation and epigenetic mechanism dissection of SET-containing proteins in orchids.

[Genome-wide identification and expression analysis of CSLA gene family of Dendrobium catenatum].

Glucomannan is the key active ingredient of Dendrobium catenatum, and CSLA family is responsible for glucomannan biosynthesis. In order to systematically evaluate the CSLA family members of D. catenatum, the bioinformatics methods were performed for genome-wide identification of DcCSLA gene family members through the genomic data of D. catenatum downloaded from the NCBI database, and further analyses of their phylogenetic relationship, gene structure, protein conserved domains and motifs, promoter cis-elements and gene expression profiles in response to stresses. The results showed that D. catenatum contains 13 CSLA members, all of which contain 9-10 exons. In the evolutionary relationship, CSLA genes were clustered into 5 groups, DcCSLA genes were distributed in all branches. Among which the ancestral genes of groupI existed before the monocot-dicot divergence, and groupⅡ-Ⅴ only existed in the monocot plants, indicating that group Ⅰ represents the earliest origin group. CSLA proteins are characteristic of the signature CESA_CaSu_A2 domain. Their promoter regions contain cis elements related to stresses and hormones. Under different stress treatments, low temperature induces the expression of DcCSLA5 and inhibits the expression of DcCSLA3. Infection of Sclerotium delphinii inhibits DcCSLA3/4/6/8/9/10 expression. Under the treatment of jasmonic acid, DcCSLA11 expression was significantly up-regulated, and DcCSLA2/5/7/12/13 were significantly down-regulated. These results laid a foundation for further study on the function of DcCSLA genes in glucomannan biosynthesis and accumulation.

[Main nutrients and functional ingredients in shoots of Polygonatum cyrtonema].

In order to reveal the main nutrients and functional ingredients in the shoots of Polygonatum cyrtonema, the polysaccharides, proteins, amino acids, and total phenols were determined. The tested samples cultured in Ma'nijiaonong, Hengtang village, Tianmushan town, Lin'an, Zhejiang, which were collected from three provenances(Pan'an and Longquan in Zhejiang and Qingyang in Anhui). The results showed that the polysaccharide content of the shoots varied from 2.34% to 12.73%, roughly one-third of rhizomes. The protein content varied from 107.75 to 192.49 mg·g~(-1), nearly 5.50 times more than rhizomes. Moreover, the average of total amino acid content was 193.13-248.74 mg·g~(-1), approximately 4.16 times of rhizomes. And the essential amino acids account for 35.57%-39.44% of the total amino acids content, which was close to the standard of the ideal protein proposed by FAO/WHO(the essential amino acid/total amino acid is about 40%). In addition, the taste amino acids(TaAA) changed from 160.12 to 208.29 mg·g~(-1), revealing the material basis of "shoots were extremely delicious" in Chinese ancient herbal medicine. Additionally, the total phenols varied from 51.21-58.76 mg·g~(-1), about 2.96 times of rhizomes. The DPPH free radical scavenging rate of tested shoots was over 95%, which obviously superior to rhizomes. Therefore, the shoots of P. cyrtonema is a very high-quality vegetable and functional food with good development potential. Furthermore, the main nutrients and functional substances in P. cyrtonema shoots are closely related to the provenances and harvesting seasons. It is important to improve the quality and yield of the shoots by strengthening the variety of breeding and cultivation techniques.

[Main nutrients and functional ingredients in flowers of Polygonatum cyrtonema and P. filipes].

To reveal the main nutrients and functional ingredients in the flowers of Polygonatum cyrtonema and P. filipes, the content of the polysaccharides, saponins, amino acids, total phenols, mineral elements, and the DPPH free radical scavenging rates were determined. The flowers and rhizomes of P. cyrtonema were collected from Qingyang in Anhui and Qingyuan in Zhejiang, while the flowers and rhizomes of P. filipes were collected from Longyou in Zhejiang, respectively. The results showed that the polysaccharides content in flowers varied from 60.88 to 97.00 mg·g~(-1), about half of that in rhizomes. The saponins content in flowers varied from 32.55 to 40.93 mg·g~(-1), which was close to the content in rhizomes. The content of total phenols ranged from 40.79 to 50.95 mg·g~(-1), approximately 4.5 times of that in rhizomes. The total amino acids content in flowers was 111.85 to 131.03 mg·g~(-1), about 2.3 times of the content in rhizomes. The essential trace element content was abundant in flowers. The contents of heavy metal elements were all within the limits set by the standards. The DPPH free radical scavenging rate IC_(50) varied from 1.77 to 3.25 mg·mL~(-1), less than one-fifth of that in rhizomes, showing a significant superiority of antioxidant activity compared to rhizomes. The results initially revealed the fundamental of "the flowers exceed the rhizomes in effect", the common saying about the traditional Chinese medicinal herbs over the years, indicating a great developing potential of the flowers. Besides, as polysaccharides, saponins, amino acids, total phenols and other nutritive substances in flowers differ widely among species and provenances, it's important to develop variety breeding to improve the quality and yield of flowers.

[Changes of pigment components in Dendrobium catenatum flower under different storage conditions].

The flower color of Dendrobium catenatum(D. officinale) tends to fade during storage. In order to clarify the influence of storage conditions on the pigment components in flowers, two conditions were applied:temperature and illumination. The contents of pigments in the D. catenatum flower were determined by UV-Vis spectrophotometry and HPLC, and the changes of them during storage were analyzed. The results showed that illumination and temperature had an effect on the pigments of D. catenatum flower during sto-rage. Illumination significantly promoted the degradation of pigments. The contents of total chlorophyll, carotenoids and anthocyanins in the light samples were significantly lower than those in the dark. The total chlorophyll, carotenoids and anthocyanins in the light samples were decreased by 46.5%, 63.4%, and 69.2% respectively. Illumination had a greater effect on fat-soluble pigments than water-soluble pigments. Among the three temperature treatments, the contents of chlorophyll, carotenoid and anthocyanin were as follows:-20 ℃>4 ℃>room temperature, it is indicated that-20 ℃ was the best temperature to maintain the stability of pigment composition. The contents of chlorophyll a, chlorophyll b, ß-carotene, lutein and zeaxanthin in the light samples decreased by 34.8%, 69.0%, 72.5%, 61.6%, 36.1%, respectively. After storage for 5 months, the contents of chlorophyll, carotenoid and anthocyanin constituent at-20 ℃ was significantly higher than those at 4 ℃ and room temperature. The results show that light avoiding and low-temperature can effectively slow down the degradation of pigment components. Therefore, it is suggested that D. catenatum flower should be stored in light avoiding and low-temperature conditions in actual production and processing, which can prolong the usable time.

[Cloning and function analysis of promoter of DcCDPK8 from Dendrobium catenatum].

DcCDPK8 involved in abiotic stress such as low temperature and signal transduction of hormones ABA and MeJA,but the transcriptional regulation is still unclear. In order to study the core promoter region of DcCDPK8 gene in Dendrobium catenatum and explore its transcriptional regulation mechanism,the DcCDPK8 gene promoter sequence was cloned by PCR from D. catenatum. Promoter sequence function was studied by fusion of 5 'terminal deletion and GUS gene. The results showed that the promoter sequence of DcCDPK8 gene has a low-temperature responsive element( LTR) between~(-1) 749 bp and-614 bp,two MeJA responsive elements between~(-1) 749 bp and-230 bp,and one ABA responsive elements between-614 bp and-230 bp. Three 5'-end different deletion fragments were constructed to fuse the eukaryotic expression vectors p BI121 with GUS,which were transformed into tobacco leaves. The GUS activity under cold stress treatment was DcCDPK8-p1>DcCDPK8-p2>DcCDPK8-p3. GUS activity under exogenous ABA induction was DcCDPK8-p1>DcCDPK8-p2>DcCDPK8-p3,and GUS activity under exogenous MeJA induction was DcCDPK8-p1>DcCDPK8-p2>DcCDPK8-p3. It is speculated that the ABA response element( ARE) in the promoter sequences of DcCDPK8 is positive regulatory role in response to exogenous ABA,the MeJA cis-acting element plays a negative role in response to exogenous MeJA.