摘要：
Ampelopsis grossedentata, commonly known as "Vine Tea" and well-recognized for its rich flavonoid content, is mainly distributed in the southern regions of the Yangtze River basin in China. These regions include Hunan, Hubei, Jiangxi, and Guizhou provinces. Vine Tea is mainly consumed as an herbal tea and has garnered attention for its reported health benefits, including antioxidant, anti-inflammatory, anti-tumor, anti-diabetic, and neuroprotective properties. It has been used to alleviate coughs and sore throats (Zhang et al., 2021; Wang et al., 2017; Gao et al., 2009). In the Zhangjiajie region of Hunan province alone, the Vine Tea planting area reached 7,670.5 hectares and produced commercial goods worth 1.417 billion RMB in 2022. In May 2021, leaf margins and veins fading to yellowing mottling, and crumpling of leaf blades in the shape of a boat symptoms were found in ~16% of Vine Tea plants in the Sanjiakuan Township, Yongding District, Zhangjiajie region (29°15'E, 110°30' N) (Figure 1a, b, c). (Figure 1a, b, c). Phytoplasma-like microbial cells (small oval shaped bacterial cells, around 1000 nm in size) were observed in sieve tube cells in the phloem of diseased leaves using transmission electron microscopy. No such cell was observed in the phloem of healthy leaves (Figure 2a, b). To investigate the potential association between phytoplasma and the observed symptoms of the diseased plants, total DNA was isolated from ten diseasedeaves and compared with ten healthy leaves from the same field using SteadyPure Plant Genomic DNA Extraction Kit. The isolated DNAs were analyzed first in a direct PCR using universal phytoplasma primer pair R16mF2/R16mR1 targeting the 16S rRNA gene (Gundersen and Lee 1996) and specific pair rpF1/rpR1 (Lee et al. 1998) targeting the DNA fragment encoding partial ribosomal proteins (rp) L22 (complete) and S3 and S19 (partial). The initial amplified products were used as templates and further amplified by nested PCR respectively with primer pair R16F2n/R16R2 for the 16S rRNA gene (Lee et al. 1998) and the rpF2/rpR2 primer pair for the rp gene (Martini et al. 2007). No amplification was obtained with DNA from healthy leaf samples using any of the four primer pairs. The amplified fragments from diseased leaves by nested PCR were cloned and sequenced (Qingke Biotech, China). The obtained sequences have been deposited in GenBank with accession numbers OR282806 for the 16S rRNA gene and GenBank OR353012 for the rp gene. BLASTn analysis revealed that the partial 16S rRNA gene sequence in our sample shared 99.4% nucleotide sequence identity with 'Candidatus Phytoplasma sp.' (MW364378) and 'Peony yellows phytoplasma' (KY814723) of the 16SrI group. Similarly, our rp gene sequence shared 99.6% nucleotide identity with the rpI group of phytoplasma such as the 'Balsamine virescence phytoplasma' (JN572890) and 'Paulownia witches'-broom phytoplasma' (HM146079). Phylogenetic analysis of the 16S rRNA and rp sequences using MEGA version 7.0 revealed that the phytoplasma strain associated with A. grossedentata yellow leaf syndrome in our study site belonged to the 16SrI (Candidatus Phytoplasma asteris) group of phytoplasma (Figure 3a, b). Using the interactive online phytoplasma classification tool iPhyClassifier (Zhao et al., 2009), virtual restriction fragment length polymorphism (RFLP) analysis of the 16S rRNA gene sequences showed our strain having a distinct RFLP map but was closest to that of the onion yellow phytoplasma 16SrI-B subgroup (GenBank accession number: AP006628), with a similarity coefficient of 0.94 (Figure 4a, b). To confirm phytoplasma transmission, healthy plants were inoculated with three scions of infected plants of A. grossedentata. After 16 days, the new leaves of the inoculated A. grossedentata showed yellow leaf symptoms (Figure 5a, b, c), akin to the symptoms originally observed in the field, and the outer contour of the leaf margin appeared chlorotic. After 26 days, primer pairs R16mF2/R16R1 and R16F2n/R16R2 were used for nested PCR detection of phytoplasma in symptomatic A. grossedentata leaves. Phytoplasma was detected in the first and second leaves of symptomatic branches and leaves while negative control showed no amplification. Sequencing of the amplified fragments showed 100% nucleotide identity to the strain from the grafting source. Our results indicated that the pathogen and the disease can be transmitted by tissue grafting, consistent with the biological characteristics of phytoplasma, and further confirmed that the phytoplasma was the pathogen of yellow leaf syndrome of A. grossedentata. Toour knowledge, this is the first report of phytoplasma of group 16SrI affecting A. grossedentata.
通讯机构：
[Li, YL; Cao, FX ] H;[Li, M ] C;Hunan Agr Univ, Coll Hort, Changsha 410128, Peoples R China.;Minist Educ, Engn Res Ctr Hort Crop Germplasm Creat & New Varie, Changsha 410128, Peoples R China.;Hunan Midsubtrop Qual Plant Breeding & Utilizat En, Changsha 410128, Peoples R China.
关键词：
Bract development;Bougainvillea glabra;MADS-box;Squamosa promoter binding protein (SBP);Plant hormone signal transduction;Chlorophyll metabolic pathways
摘要：
BACKGROUND: Bracts are important for ornamental plants, and their developmental regulation process is complex; however, relatively little research has been conducted on bracts. In this study, physiological, biochemical and morphological changes in Bougainvillea glabra leaves, leaf buds and bracts during seven developmental periods were systematically investigated. Moreover, transcriptomic data of B. glabra bracts were obtained using PacBio and Illumina sequencing technologies, and key genes regulating their development were screened. RESULTS: Scanning electron microscopy revealed that the bracts develop via a process involving regression of hairs and a color change from green to white. Transcriptome sequencing revealed 79,130,973bp of transcript sequences and 45,788 transcripts. Differential gene expression analysis revealed 50 expression patterns across seven developmental periods, with significant variability in transcription factors such as BgAP1, BgFULL, BgCMB1, BgSPL16, BgSPL8, BgDEFA, BgEIL1, and BgBH305. KEGG and GO analyses of growth and development showed the involvement of chlorophyll metabolism and hormone-related metabolic pathways. The chlorophyll metabolism genes included BgPORA, BgSGR, BgPPH, BgPAO and BgRCCR. The growth hormone and abscisic acid signaling pathways involved 44 and 23 homologous genes, and coexpression network analyses revealed that the screened genes BgAPRR5 and BgEXLA1 are involved in the regulation of bract development. CONCLUSIONS: These findings improve the understanding of the molecular mechanism of plant bract development and provide important guidance for the molecular regulation and genetic improvement of the growth and development of ornamental plants, mainly ornamental bracts.
关键词：
activity zone;landscape features;seasonal and diurnal variations;urban park;visitation density
摘要：
Urban parks are the main place for physical activities, generating numerous benefits to enhance human well-being. Many studies have investigated the impacts of landscape features on park visitation but ignored their seasonal and diurnal variations. Taking the Hunan Martyr Park in China as an example, this study aims to assess the seasonal and diurnal variations in the impacts of landscape features on visitation density. We quantified visitation density for 109 activity zones for both daytime and nighttime in summer and winter and investigated the impacts of landscape features of the activity zone and the surrounding environments on visitation density based on 16 quantitative indicators. The results show that: (1) The impacts of ground condition, connection to water, distance to park entrances, and distance to stores were consistent in different periods. Paved activity zones, zones close to water, zones further away from the park entrances, and zones closer to the stores had significantly higher visitation density. (2) Shading degree, connected pathway, and distance to toilets had contrasting impacts between summer and winter. Zones with a higher shading degree attracted more visitors in summer and deterred visitors in winter. Zones with fewer pathways connected and zones farther away from toilets had higher visitation density in summer but not in winter. (3) Shading degree, number of trees, presence of facilities (e.g., benches, tables, pavilion, and light devices), and connected pathway had contrasting impacts between daytime and nighttime. Zones with a high shading degree, zones with benches and pavilions, and zones without trees had higher visitation density in the daytime. Zones with light devices, zones with more connected pathways, and zones without tables had higher visitation density at nighttime. These findings highlighted the seasonal and diurnal variation of the impacts of landscape features on park visitation and can help to improve urban park design, especially for cities with hot summers and cold winters.
作者机构：
[Zhang, Donglin; Zhang, Yifan; Yu, Xiaoying; Li, Yanlin; Xiong, Xingyao; Liu, Yang; Li, YL] Hunan Agr Univ, Coll Hort, Hunan Midsubtrop Qual Plant Breeding & Utilizat En, Engn Res,Ctr Hort Crop Germplasm Creat & New Varie, Changsha 410128, Peoples R China.;[Lin, Ling] Hunan Agr Univ, Sch Econ, Changsha 410128, Peoples R China.;[Xiong, Xingyao] Chinese Acad Agr Sci, Agr Genom Inst Shenzhen, Shenzhen 518120, Peoples R China.;[Li, Yanlin; Xiong, Xingyao; Li, YL] Kunpeng Inst Modern Agr, Foshan 528225, Peoples R China.;[Zhang, Donglin] Univ Georgia, Dept Hort, Athens, GA 30602 USA.
通讯机构：
[Yu, XY; Li, YL ] H;Hunan Agr Univ, Coll Hort, Hunan Midsubtrop Qual Plant Breeding & Utilizat En, Engn Res,Ctr Hort Crop Germplasm Creat & New Varie, Changsha 410128, Peoples R China.;Kunpeng Inst Modern Agr, Foshan 528225, Peoples R China.;Nanyang Technol Univ, Sch Biol Sci, 60 Nanyang Dr, Singapore 637551, Singapore.
关键词：
Loropetalumchinense var. rubrum;WRKY;expression pattern;genome-wide analysis;light quality
摘要：
The WRKY gene family plays important roles in plant growth and development, as well as in the responses to biotic and abiotic stresses. Loropetalum chinense var. rubrum has high ornamental and medicinal value. However, few WRKY genes have been reported in this plant, and their functions remain unknown. To explore the roles that the WRKY genes play in L. chinense var. rubrum, we identified and characterized 79 LcWRKYs through BLAST homology analysis and renamed them (as LcWRKY1-79) based on their distribution on the chromosomes of L. chinense var. rubrum. In this way, according to their structural characteristics and phylogenetic analysis, they were divided into three groups containing 16 (Group I), 52 (Group II), and 11 (Group III) WRKYs, respectively. LcWRKYs in the same group have similar motifs and gene structures; for instance, Motifs 1, 2, 3, 4, and 10 constitute the WRKY domain and zinc-finger structure. The LcWRKY promoter region contains light response elements (ACE, G-box), stress response elements (TC-rich repeats), hormone response elements (TATC-box, TCA-element), and MYB binding sites (MBS, MBSI). Synteny analysis of LcWRKYs allowed us to establish orthologous relationships among the WRKY gene families of Arabidopsis thaliana, Oryza sativa, Solanum lycopersicum L., Vitis vinifera L., Oryza sativa L., and Zea mays L.; furthermore, analysis of the transcriptomes of mature leaves and flowers from different cultivars demonstrated the cultivar-specific LcWRKY gene expression. The expression levels of certain LcWRKY genes also presented responsive changes from young to mature leaves, based on an analysis of the transcriptome in leaves at different developmental stages. White light treatment led to a significant decrease in the expression of LcWRKY6, 18, 24, 34, 36, 44, 48, 61, 62, and 77 and a significant increase in the expression of LcWRKY41, blue light treatment led to a significant decrease in the expression of LcWRKY18, 34, 50, and 77 and a significant increase in the expression of LcWRKY36 and 48. These results enable a better understanding of LcWRKYs, facilitating the further exploration of their genetic functions and the molecular breeding of L. chinense var. rubrum.
作者机构：
[Mo, Qiong; Zhang, Damao; Yu, Xiaoying; Xiong, Xingyao; Li, Yanlin; Liu, Yang; Li, YL] Hunan Agr Univ, Coll Hort, Engn Res Ctr Hort Crop Germplasm Creat & New Varie, Hunan Midsubtrop Qual Plant Breeding & Utilizat En, Changsha 410128, Peoples R China.;[Lin, Ling] Hunan Agr Univ, Sch Econ, Changsha 410128, Peoples R China.;[Li, Weidong] Hunan Acad Agr Sci, Hunan Hort Res Inst, Hunan Key Lab Germplasm Innovat & Comprehens Utili, Changsha 410125, Peoples R China.;[Xiong, Xingyao; Li, Yanlin; Li, YL] Chinese Acad Agr Sci, Agr Genom Inst Shenzhen, Shenzhen 518120, Peoples R China.;[Xiong, Xingyao; Li, Yanlin; Li, YL] Kunpeng Inst Modern Agr, Foshan 528225, Peoples R China.
通讯机构：
[Yu, XY; Xiong, XY; Li, YL ] H;Hunan Agr Univ, Coll Hort, Engn Res Ctr Hort Crop Germplasm Creat & New Varie, Hunan Midsubtrop Qual Plant Breeding & Utilizat En, Changsha 410128, Peoples R China.;Chinese Acad Agr Sci, Agr Genom Inst Shenzhen, Shenzhen 518120, Peoples R China.;Kunpeng Inst Modern Agr, Foshan 528225, Peoples R China.;Nanyang Technol Univ, Sch Biol Sci, 60 Nanyang Dr, Singapore 637551, Singapore.
关键词：
L. chinense var. rubrum;bHLH transcription factor;expression analyses;anthocyanin
摘要：
<jats:p>The basic helix–loop–helix (bHLH) transcription factor family is the second-largest transcription factor family in plants. Members of this family are involved in the processes of growth and development, secondary metabolic biosynthesis, signal transduction, and plant resistance. Loropetalum chinense var. rubrum is a critical woody plant with higher ornamental and economic values, which has been used as ornamental architecture and traditional Chinese herbal medicine plants. However, the bHLH transcription factors in Loropetalum chinense var. rubrum (L. chinense var. rubrum) have not yet been systematically demonstrated, and their role in the biosynthesis of anthocyanin is still unclear. Here, we identified 165 potential LcbHLHs genes by using two methods, and they were unequally distributed on chromosomes 1 to 12 of the genome of L. chinense var. rubrum. Based on an evolutionary comparison with proteins from Arabidopsis and Oryza sativa, these bHLH proteins were categorized into 21 subfamilies. Most LcbHLHs in a particular subfamily had similar gene structures and conserved motifs. The Gene Ontology annotation and Cis-elements predicted that LcbHLHs had many molecular functions and were involved in processes of plant growth, including the biosynthesis of flavonoids and anthocyanins. Transcriptomic analysis revealed different expression patterns among different tissues and cultivars of L. chinense var. rubrum. Many LcbHLHs were expressed in the leaves, and only a few genes were highly expressed in the flowers. Six LcbHLHs candidate genes were identified by bioinformatics analysis and expression analysis. Further Real-time quantitative PCR analysis and protein interaction network analysis showed that LcbHLH156, which is one of the candidate proteins belonging to the IIIf subfamily, could interact with proteins related to anthocyanin synthesis. Therefore, LcbHLH156 was transiently expressed in L. chinense var. rubrum to verify its function in regulating anthocyanin synthesis. Compared with the control group, red pigment accumulation appeared at the wound after injection, and the total anthocyanin content increased at the wound of leaves. These results lay a foundation for the research of the regulation mechanism of leaf colors in L. chinense var. rubrum and also provide a basis for the function of the LcbHLH family.</jats:p>
作者机构：
[李旭; 侯志勇; 谢永宏; Li, Xu; Zeng, Jing] Key Laboratory of Agro-ecological Processes in Subtropical Region, Dongting Lake Station for Wetland Ecosystem Research, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha;410125, China;[于晓英] College of Horticulture, Hunan Agricultural University, Changsha;410128, China;[李旭] 410125, China <&wdkj&> College of Horticulture, Hunan Agricultural University, Changsha
作者机构：
[陈倩如; 许璐; 张霞; 张大毛; 蔡文淇] College of Horticulture, Hunan Agricultural University, Hunan Mid-subtropical Quality Plant Breeding and Utilization Engineering Technology Research Center, Changsha, 410128, China;[李卫东] Hunan Prov. Key Laboratory of Germplasm Innovation and Comprehensive Utilization of Garden Flowers, Changsha, 410128, China;Engineering Research Center for Horticultural Crop Germplasm Creation and New Variety Breeding, Ministry of Education, Changsha, 410128, China;[于晓英; 李炎林] College of Horticulture, Hunan Agricultural University, Hunan Mid-subtropical Quality Plant Breeding and Utilization Engineering Technology Research Center, Changsha, 410128, China, Engineering Research Center for Horticultural Crop Germplasm Creation and New Variety Breeding, Ministry of Education, Changsha, 410128, China
通讯机构：
[Yu, X.; Li, Y.] C;College of Horticulture, China
摘要：
为探讨同一时间内黄心夜合Michelia martinii鲜叶、鲜嫩枝和鲜花的挥发油成分,利用气相色谱-质谱联用技术(GC-MS)对水蒸气蒸馏法提取的黄心夜合鲜叶、鲜嫩枝和鲜花挥发油成分进行了分析。结果表明:去掉峰值0.49以下的峰,从黄心夜合鲜叶、鲜嫩枝、鲜花分别检测出21种、31种和25种成分, 3种不同组织样品共有2,4-二异丙烯基-1-甲基环己烷、γ-依兰油烯、4(14),11-桉叶二烯、γ-榄香烯等4种成分,而鲜叶与鲜嫩枝都释放共同的12种挥发性成分,鲜嫩枝与鲜花都释放共同的13种挥发性成分,鲜叶与鲜花都释放共同的4种挥发性成分。黄心夜合鲜叶、鲜嫩枝和鲜花的挥发油成分在提取材料选择、挥发性成分利用与养生保健群落的营建等方面具有一定的应用参考。 <&wdkj&>To study volatile components from fresh leaves, fresh twigs, and fresh flowers of Michelia martinii at the same time, volatile oils were extracted by water-steam distillation from the fresh leaves, fresh twigs, and fresh flowers and then detected by gas chromatography-mass spectrometry (GC-MS). Results of GC-MS showed that the volatile oils contents from different organizations of M. martinii at the same time had ingredients of 21 kinds from fresh leaves, of 31 kinds from fresh twigs, and of 25 kinds from fresh flowers (peak values below 0.49 were neglected). Among the three fresh organizations of M. martinii, the common components were four kinds of ingredients, such as .gamma.-Elemene, gamma.-Muurolen, Eudesma-4(14),11-diene, and Cyclohexane, 2,4-diisopropenyl-1-methyl-. Four kinds of components were common to fresh leaves and fresh flowers, 13 kinds of components were common to fresh flowers and fresh twigs, and 12 kinds of components were common to fresh leaves and fresh twigs. The volatile oils of flowers were rich in terpenes and alcohols with terpenes dominated by monoterpenes up to 36.38%; content of the alcohol compounds was higher than terpenes with content as high as 54.77%. Terpene compounds had .gamma.-Cadinene, Caryophyllene oxide, .alpha.-Selinene, Spathulen, Diepicedrene-1-oxide, (+)-Ledene, -Aristolene, Eudesma-4 (14),11-diene, and DGermacrene D. While the alcohols had Eudesm-4 (14)-en-11-,2-(4,8-Dimethyl-3,7-cyclodecadien-1-yl)-2-p, Epiglobulol,.gamma.-Eudesmol, .tau.-Cadinol, Guaiol, and .delta.-Cadinol. In conclusion M. mar tinii could provide new application ideas on material selection of extracted essential oils, utilization of volatile components, and landscape community construction for health care.
摘要：
.This study aimed to investigate the hypolipidemic and antioxidant activities of volatile oils from Michelia martini Levl. The antioxidant property of volatile oils from Michelia martini in vitro was investigated by establishment of various systems. High fat diet induced rats were used to assess the hypolipidemic and antioxidant activities of Michelia martini volatile oils in vivo. The level of total cholesterol, triglycerides, high density lipoprotein cholesterol, low density lipoprotein cholesterol, alanine transaminase, aspartate aminotransferase, alkaline phosphatase and gamma-glutamyl transpeptidase in serum, and the activities of catalase, malondialdehyde, super oxide dismutase and glutathione in liver of rats were assayed by standard procedures. Our results showed that Michelia martini exhibits strong hypolipidemic and antioxidant activities both in vitro and vivo. Our data were also supplemented with histopathological studies on liver tissues and aorta sections of rats.
关键词：
Callus;Hydropriming;Paclitaxel;Taxoid-metabolite;Taxus chinensis var. mairei;Tube plantlet
摘要：
The half-sib population is an abundant of gene pool for selection breeding of lines or cultivars with high paclitaxel. The seeds, collected from the sampling tree of Taxus chinensis var. mairei, were exposed to hydropriming and incubated plantlets and which induced callus to screen stable and high paclitaxel content of cell lines. Seed dormancy was successfully broken with 100% germination rate by hydropriming for three to five days. Embryo germination was inhibited by illumination. The optimal medium for in vitro embryo germination was MS-modified media (BLG media) supplemented with 20 g/L sucrose, 5 g/L activated carbon and 7 g/L agar. The embryos were transferred to a 14 h photoperiod after seven days incubation in darkness. Seedling plantlets were obtained after fifty days in vitro. Embryonic calluses were induced with frequencies up to 73% and cultured in BLG medium supplemented with 2 mg/L 2,4-dichlorophenoxyacetic-D (2,4-D), 0.5 mg/L 6-benzyladenine (6-BA), 20 g/L sucrose and 7 g/L agar. The half-sib cell lines showed high variation levels of taxoids metabolite. Thus, a cell line with high paclitaxel content [60.87 mg/100 g fresh weight] was obtained. Our study provides a new strategy to achieve high seed germination rate and seedling plantlet growth of T. chinensis var. mairei. It is suitable for screening cell lines with high paclitaxel content, obtained from half-sib cells that initiated from the seedling plantlets of T. chinensis var. mairei. (C) 2019 Friends Science Publishers
