Abiotic stress treatment reveals expansin like A gene OfEXLA1 improving salt and drought tolerance of Osmanthus fragrans by responding to abscisic acid

Sweet osmanthus(Osmanthus fragrans) is a having general approval aromatic tree in China that is widely applied to landscaping and gardening. However, the evergreen tree adaptability is limited by many environmental stresses. Currently, limited information is available regarding the genetic analysis and functional identification of expansin genes in response to abiotic stress in sweet osmanthus. In this study, a total of 29 expansin genes were identified and divided into four groups by genome-wide analysis from the sweet osmanthus genome. Transcriptome and quantitative Real-time PCR analysis showed that the cell wall-localized protein expansin-like A(OfEXLA1) gene was significantly induced by salt and drought treatment. Histochemical GUS staining of transgenic Arabidopsis lines in which GUS activity was driven with the OfEXLA1 promoter, GUS activity was significantly induced by salt, drought, and exogenous abscisic acid(ABA). In yeast, we found OfEXLA1overexpression significantly improved the population of cells compared with wild-type strains after NaCl and polyethylene glycol(PEG)treatment. Additionally, OfEXLA1 overexpression not only promoted plant growth, but also improved the salt and drought tolerance in Arabidopsis. To gain insight into the role of ABA signaling in the regulation of OfEXLA1 improving abiotic tolerance in sweet osmanthus, four differentially expressed ABA Insensitive 5(ABI5)-like genes(OfABL4, OfABL5, OfABL7, and OfABL8) were identified from transcriptome, and dualluciferase(dual-LUC) and yeast one hybrid(Y1H) assay showed that OfABL4 and OfABL5 might bind to OfEXLA1 promoter to accumulate the OfEXLA1 expression by responding to ABA signaling to improve abiotic tolerance in sweet osmanthus. These results provide the information for understanding the molecular functions of expansin-like A gene and molecular breeding of sweet osmanthus in future.

Study on the molecular mechanism of Osmanthus fragrans Lour.on boosting immunity based on network pharmacology and molecular docking

Objective:To explore the molecular mechanism of Osmanthus Fragrans Lour.(OFL)in enhancing immunity.Methods:The compounds and action targets of OFL were collected from the Traditional Chinese Medicine Systematic Pharmacology Database and Analysis Platform.Protein targets of compounds were obtained from the UniProt database and relevant targets of boosting immunity were retrieved from the Genecards database.The Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis and Gene Ontology function enrichment analysis were performed through the DAVID analysis website,Visualization and Integrated Discovery.Finally,the results of the network analysis were validated by performing molecular docking using AutoDock vina.Results:A total of 7 active compounds and 167 potential active targets were identified in OFL.A total of 1549 genes with a correlation score of≥1 were retrieved from the Genecards website with the keyword“boost immunity”,and 107 genes were obtained by crossing the 167 genes of OFL with the 1549 genes of boosting immunity.A total of 4802 entries were obtained from Gene Ontology functional enrichment(P<0.05).A total of 234 signaling pathways were obtained through a Kyoto Encyclopedia of Genes and Genomes pathway analysis(P<0.05).Tumor necrosis factor(TNF)and interleukin 17(IL-17)signaling pathways were closely related to body immunity.The molecular docking results showed that all the core compounds in OFL the characteristics including low energy,a stable structure and high binding activity when bound to IL-17 and TNF-αprotein.Kaempferol showed the highest affinity with IL-17,and fucosterol showed the highest affinity with TNF-α.Conclusions:Through studies on network pharmacology and molecular docking,we have further demonstrated that OFL could enhance the immunity of the body through multi-component,multi-target and multi-pathway actions,and that IL-17/TNF-αsignalling pathway is the key molecular mechanism.

Differences in leaf functional traits between red and green leaves of two evergreen shrubs Photinia×fraseri and Osmanthus fragrans

Leaf functional traits are adaptations that enable plants to live under different environmental conditions. This study aims to evaluate the differences in leaf functional traits between red and green leaves of two evergreen shrubs Photinia × fraseri and Osrnanthus fragrans. Specific areas of red leaves are higher than that of green leaves in both species. Thus, the material investment per unit area and per lamina of red leaves is significantly lower than that of green leaves, implying an utmost effort of red leaves to increase light capture and use efficiency because of their low leafchlorophyll concentration. The higher petiole length of green leaves compared with that of red leaves indicates that adult green leaves may have large fractional biomass allocation to support the lamina structures in capturing light with maximum efficiency and obtaining a high growth rate. The high range of the phenotypic plasticity of leaf size, leaf thickness, single-leaf wet and dry weights, and leaf moisture of green leaves may be beneficial in achieving efficient control of water loss and nutrient deprivation. The high range of phenotypic plasticity of leaf chlorophyll concentration of red leaves may be advantageous in increasing resource （especially light） capture anduse efficiency because this leaf type is juvenile in the growth stage and has low leaf-chlorophyll concentration.

CPTA treatment reveals potential transcription factors associated with carotenoid metabolism in flowers of Osmanthus fragrans

Osmanthus fragrans is one of the top ten traditional flowers in China.It is divided into three different groups according to its color.α-Carotene and β-carotene are the main determinants to distinguish the color differences between three groups.However,the dominant genes and transcription factors involved in carotenoid metabolism remain unclear.CPTA treatment(0.7mmol·L−1)remarkably promoted lycopene,α-carotene and β-carotene contents in flowers.Transcriptome sequencing analysis revealed that CPTA treatment could trigger chain reactions in carotenoid metabolism pathway genes.Four up-regulated and 10 down-regulated transcription factors which have close association with carotenoid variation were significantly induced by CPTA treatment.The up-regulated TFs such as MYB43,MYB123,HSF,were further subjected to transcript expression determination in different cultivars with drastic colors.Among them,transcript expression of four up-regulated TFs coincided with the carotenoid accumulation in different cultivars.We selected up-regulated OfMYB43 to verify its function,which is related to stress tolerance and transcriptional regulation.Transient overexpression of OfMYB43 in O.fragrans flowers showed that it could remarkably promote the expression of PDS,ZISO,LCYE and CCD4,leading to increased accumulation of β-branch carotenoids.OfMYB43 was a potential positive regulator of carotenoid biosynthesis in O.fragrans flowers.This study provides insight into the molecular mechanism of carotenoid metabolism in O.fragrans.

Identification and quantification of the bioactive components in Osmanthus fragrans roots by HPLC-MS/MS

The roots of O. fragrans are also a valuable resource in addition to its flowers and fruits. In this study, the HPLC-MS/MS method used for analyzing the chemical constituents in O. fragrans roots extract was developed, which showed high sensitivity for both qualitative and quantitative analyses. Thirty-two compounds were first discovered in O. fragrans roots, one compound of which was reported for the first time. The simultaneous determination method for acteoside, isoacteoside, oleuropein and phillyrin was validated to be sensitive and accurate. Then it was applied to determine the content of bioactive components in O. fragrans roots from different cultivars. The content of oleuropein and phillyrin in the twelve batches was relatively stable, while the content of acteoside and isoacteoside varied greatly.Moreover, the therapeutic material basis and mechanism of O. fragrans roots exerting its traditional pharmacodynamics were analyzed by network pharmacology. The results showed that O. fragrans roots might be effective for the treatment of inflammation, cardiovascular diseases, cancer, and rheumatoid arthritis, which is consistent with the traditional pharmacodynamics of O. fragrans roots. This work can provide an analytical method for the comprehensive development of O. fragrans roots.

Study on Prediction of the First Flowering Date of Osmanthus fragrans

[ Objective] The study aimed to forecast the first flowering date of Osmanthus fragrans. [ Method] Based on the data about flowering stage of O. fragrans in Guilin City from 1999 -2012, the correlation between meteorological factors and the first flowering date of O. fragrans was analyzed, and a forecast model for the first flowering date of O. fragrans was established. EResult] Among meteorological factors, precipitation, humidity, temperature and sunshine hours could obviously affect the first flowering date of O. fragrans, especially humidity in August, temperature and sunshine hours in September. The forecast model could exactly forecast the first flowering date in the partial early or too late year, and the av- erage error of date was 6 days. The factors influencing the first flowering date of O. fragrans are complex, and there is an artificial error in record data of the flowering stage, so using a single model to forecast the first flowering date have some disadvantages. When forecasting the first flower- ing date, we should consider all influencing factors to get a good forecast result. [ Conclusion] The research could provide a new method to forecast the first flowednq date of O. fraclrans.

Development Prospects of Osmanthus fragrans Mixed Wine Based on Liquor and Spirits

As a plant resource, Osmanthus fragrans has both medicinal and edible effects. This paper reviews the active components and health-care functions of O. fragrans, and introduces the current research situation of O. fragrans mixed wine. In addition, combined with the development of new products of plant-based flower wine, it analyzes the development prospects of O. fragrans mixed wine based on liquor and spirits.

Analysis of Fragrance Composition in Three Cultivars of Osmanthus fragrans Albus Group Flower by Gas Chromatography-Mass Spectrometry

With supercritical CO2 fluid extraction（SCFE）, essential oil was extracted from three cultivars of Xianning osmanthus. The fresh osmanthus flower was processed with a petroleum ether digestion method to produce the extractum. The yields of essential oil and extractum were 0.19 % and 0.13 % （m/m） respectively. The essential oil and fragrance composition and content extracted were analyzed with gas chromatography-mass spectrometer （GC-MS）. The result showed that essential oil contained 36.99%（area/total area） of ionone, ionol and 13.11% of linalool; ionone and ionol contained in extractum were as high as up to 33.33%, while linalool up to 21.92%. Whether essential oil or extractum contains only about 40% fat acid and other ester matters. None of environmental estrogen （phthalic ester） was found in fragrance ingredients. The result also showed that the quality of O. fragrans Albus group fragrance in Xianning is better than that produced in Hangzhou and Anhui districts.

两种彩叶桂花新品种光合特性的比较研究

为了探讨2个彩叶桂花(Osmanthus fragrans L.)新品种(虔南桂妃、紫嫣公主)需光特性,测定4个不同桂花品种生长高峰期的光响应曲线。通过相关分析,探讨4种桂花净光合速率(Pn)。结果表明,各桂花品种净光合速率随光合有效辐射(PAR)的增加而迅速增加,在PAR>200μmol/(m^2·s)时逐渐稳定。净光合速率日变化的影响因子存在显著差异。两个彩叶桂花新品种的光饱和点(LSP)、光补偿点(LCP)与其他2个桂花品种的相比较低,弱光利用效率也较强,具有较好的耐阴性。

低温对桂花万点金叶肉细胞超微结构的影响

为探讨桂花万点金Osmanthus fragrans‘Wandian Jin’在低温胁迫下叶肉细胞溶酶体等细胞器超微结构的变化规律,以3年桂花品种万点金为试材,模拟自然降温过程胁迫桂花植株,经取样制片后,用透射电子显微镜拍照。结果表明:常温条件下,叶绿体线粒体结构正常;溶酶体数量较少。5℃低温处理时,部分叶绿体较之常温发生肿胀;嗜锇体和线粒体数量较之常温有增多现象;初级溶酶体和次级溶酶体并存,数量增多。0℃低温胁迫时,叶绿体膨胀加剧,部分呈椭球形;嗜锇体较多;淀粉粒有肿胀变大的现象;线粒体数量增多;次级溶酶体结构复杂多样,大小不一。-5℃低温胁迫处理时,叶绿体较前期的低温胁迫肿胀更加剧烈,部分叶绿体向细胞中央游离;线粒体增多;初级溶酶体和次级溶酶体数量增多,形态多样;叶肉细胞有胞内结冰和胞间结冰现象。

桂花OfCYP82C4基因的克隆及表达分析

本研究运用RT-PCR和RACE方法,从‘橙红丹桂’中克隆出了桂花OfCYP82C4基因。生物信息学分析表明,本实验所克隆的基因(全长1542 bp)是CYP450基因家族的成员之一;时空表达分析发现,OfCYP82C4基因在花器官中特异性高表达,营养器官根、叶中表达量均很低;在开花过程中OfCYP82C4的表达谱(从铃梗期到盛花期)与花瓣内β-胡萝卜素的含量变化趋势相似,从盛花初期至末花期,该基因表达量还在持续增加,到末花期达到峰值。据此我们推测OfCYP82C4基因可能参与桂花类胡萝卜素的代谢调控,在开花的中后期参与调节的花器官衰老的生理代谢过程。研究结果为深入系统地了解OfCYP82C4基因在桂花代谢过程中的调控功能提供理论依据。

盐胁迫对‘堰虹桂’生长、光合及离子分配的影响

以观赏价值高和抗逆性较强的‘堰虹桂’(Osmanthus fragrans‘Yanhong’)作为试验材料,研究了不同浓度(CK、3‰、5‰和7‰)盐(NaCl)胁迫对其幼苗生长、光合作用、蒸腾速率以及根系和叶片中Na^(+)和K^(+)分配的影响,以期判断该类植物是否耐盐以及耐盐的范围。研究发现,随着盐胁迫的增加,‘堰虹桂’幼苗抽梢量不受影响,但高生长在5‰和7‰时受到明显抑制;植株光合作用和蒸腾速率显著降低;随盐胁迫的增加,根系和叶片中的Na^(+)含量以及Na^(+)/K^(+)总体增加,而K^(+)含量则显著降低。通过生长和生理生化指标的综合分析发现,‘堰虹桂’若作为滨海盐渍化土壤绿化植物,只适合在<3‰的土壤盐浓度下种植。