Transcriptomic Analysis Reveals the Formation Mechanism of Anthocyanins Light-Independent Synthesis in Chrysanthemum

Chrysanthemum×morifolium is a horticultural crop which plays a vital role in theflower industry with signifi-cant economic value and has a cultivation history of over three thousand years in China.The accumulation of anthocyanins is always affected by light.Here,we revealed that anthocyanin accumulation is highly dependent on light in‘2021135’genotype chrysanthemum,while it is light-independent in‘2001402’genotype chrysanthe-mum.However,no literature has been reported regarding the non-photosensitive chrysanthemum in anthocya-nins light-independent synthesis pathways.Through the phenotype analysis of 44 F1 generations,we found that light-independence is a dominant trait which can be stable inherited by progeny.The transcriptome of the rayflorets of‘2021135’and‘2001402’under light and bagging treatment were sequenced and analyzed.Based on weighted gene co-expression network analysis(WGCNA),K-means analysis,and Real-Time Quantitative Poly-merase Chain Reaction(RT-qPCR)analysis,16 genes were highly correlated with the anthocyanin content.The anthocyanin content of rayflorets treated with different light-quality conditions indicated that blue light signifi-cantly affected anthocyanin accumulations.Through Yeast one-hybrid analysis,CmBIC1.1 and CmBIC1.2 can directly regulate the anthocyanin structural gene CmCHS2.In our study,we revealed the important characteristics of light-independent anthocyanin synthesis in chrysanthemums and screened regulatory factors in light-depen-dent and light-independent anthocyanin synthesis pathways.The results laid the groundwork for subsequent ana-lysis of the molecular mechanism involved in the light-independent synthesis of anthocyanins in chrysanthemums.

Flavonoid extracts from chrysanthemum with appropriate anthocyanins turn blue when exposed to iron ions

Although some species that accumulate only cyanidin(Cy)in nature can produce blue flowers through iron ions,there has been no evidence of blue chrysanthemums being generated in this manner.This study revealed that flavonoid extracts from the ray florets of the chrysanthemum cultivar‘Wandai Fengguang’turned blue when exposed to Fe^(3+).Samples that could turn blue were labeled as CB(Cy-determined blue flowers),while samples that did not turn blue were labeled as CN(Cy-determined non-blue flowers).After a series of experiments,a stable screening system was established using flavonoid extracts containing NaAc buffer at pH 5.5 and a total anthocyanin concentration(TAC)of 30 μmol·L^(-1),and the addition of Fe^(3+)from 0 to 0.25 μmol·L^(-1)allowed for the selection of five CB samples from 39 chrysanthemum cultivars.All five CB samples exhibited flower color phenotypes that belonged to Cluster-I with redness(a*)values ranging from 29.03 to 45.99,yellowness(b*)values from-11.31 to 3.77,and brightness(L*)values from 29.07 to 45.99.Additionally,the ratio of TAC to total luteolin concentration(TLC)was found to be a critical factor for distinguishing between CB and CN samples.To realize the desired blue hue in the flavonoid extracts with the participation of Fe^(3+),a TAC to TLC ratio of 2.25 and above is required.Moreover,the protoplasts and ray florets of CB samples that turned blue with the involvement of Fe^(2+)showed great potential for cultivating blue chrysanthemums through ferric-anthocyanin chelate.Overall,this study reveals that blue flowers can be cultivated through the increase in the iron ion concentration,combined with the accumulation of Cy.

FLOWERING LOCUS T(FT)in Photosensitive Type Chrysanthemum Accelerates Flowering in Arabidopsis

FLOWERING LOCUS T(FT)is an important factor for integrating flowering signals through the photoperiod pathway,which significantly promotes flowering.Most chrysanthemum varieties are short-day plants,sensitive to the photoperiod,which limits their ornamental and annual production supply.In this study,we aim to analyze the nutrients and flowering-related genes of chrysanthemums with different photoperiod types and to clone and verify the function of the flowering-related gene CmFT.We found that the formation of floral buds requires the accumulation of starch while consuming soluble sugars and the expression patterns of flowering-related genes GIGANTEA(GI),CONSTANS(CO),and FT in C.morifolium‘Zilian’and C.morifolium‘Zihongtuogui’had a certain synchronization during floral buds differentiation according to our quantitative validation,and the expression levels of CmGI,CmCO and CmFT in C.morifolium‘Zihongtuogui’were higher than those in C.morifolium.‘Zilian’in the later stage of differentiation.CmFT was cloned from photosensitive chrysanthemums-C.morifolium‘Zihongtuogui’and polypeptide alignment and phylogenetic analysis showed that CmFT was clustered in FT-like subfamily.In further functional verification,we obtained two Arabidopsis transgenic lines.Our results showed that CmFT transgenic ft mutant lines can significantly accelerate flowering in Arabidopsis.Thus,we can initially confirm that CmFT plays an important role in promoting flowering,which may be the key reason for the photosensitivity of C.morifolium‘Zihongtuogui’.Overall,the results of this study are of great importance in revealing the flowering mechanism of different photoperiod types of chrysanthemums.

Pharmacological effects of volatile oil from chrysanthemum and its associated mechanisms:a review

Volatile oil(VO)is the main chemical component of common plants in Chrysanthemum genus,and it possesses several beneficial pharmacological properties,including bacteriostatic,antioxidant,anti-tumor,anti-inflammatory,antipyretic,analgesic,antiosteoporotic,antihypertensive,sedative,and hypnotic effects.To date,research on the effective components of Chrysanthemum extract has mainly focused on flavonoids,whereas limited data are available on the chemical constituents and underlying mechanisms of action of the VO components.In this review,the pharmacological activities and mechanisms of VO are comprehensively reviewed with the aim of providing a foundation for further development for medicinal,aromatherapy,and diet therapy applications.

CmMYB3-like negatively regulates anthocyanin biosynthesis and flower color formation during the post-flowering stage in Chrysanthemum morifolium

Color fading caused by a decrease in anthocyanin accumulation during the post-flowering stage significantly affects postharvest quality of chrysanthemum.However,the underlying mechanism by which anthocyanin accumulation decreases during the post-flowering stage still unclear,which greatly restricts design of molecular breeding in chrysanthemum.Here,a chrysanthemum SG7 R2R3 MYB transcription factor(TF),CmMYB3-like,was identified to have a function in regulating anthocyanin biosynthesis during the post-flowering stage.Quantitative real time PCR(qRT-PCR)assays showed that the expression of CmMYB3-like was gradually downregulated when anthocyanin content increased during the flowering stage and was significantly upregulated during the post-flowering stage.Genetic transformation of chrysanthemum and dual-luciferase assays in N.benthamiana leaves showed that CmMYB3-like suppressed anthocyanin accumulation by inhibiting the transcription of CmCHS and CmANS directly and that of CmF3H indirectly.However,overexpression or suppression of CmMYB3-like did not affect the biosynthesis of flavones or flavonols.Genetic transformation of chrysanthemum revealed that the overexpression of CmMYB3-like inhibited anthocyanin accumulation,but its suppression prevented the decrease in anthocyanin accumulation during the post-flowering stage.Our results revealed a crucial role of CmMYB3-like in regulating the color of petals during the post-flowering stage and provided a target gene for molecular design breeding to improve the postharvest quality of chrysanthemum.

基于主成分及聚类分析的药用菊花品种产量与品质综合评价

为防止品种混杂,筛选药用或茶用菊花的专用品种,以不同产地来源的8个药用菊花品种16个样品为试材,采用超高效液相色谱法和比色法测定不同产地药用菊花的品质成分含量;并基于主成分分析和聚类分析,对不同产地药用菊花品种产量与品质进行综合评价。结果表明,不同产地药用菊花品种单株花头数变异系数(39.03%)最大,是构成药用菊花单株花头干重的主要因素(r=0.800),以枣庄红心菊单株花头数(496.50)最多、单株花头干重最高;绿原酸、3,5-O-二咖啡酰基奎宁酸和总黄酮等药效成分在不同来源的样本中差异显著(P<0.05),上述三种成分在滁州产滁菊中相对含量较高,分别为3.75%、8.07%、16.08%,这与其品质成分综合评价结果一致,说明滁州滁菊药效较优。13个性状指标的主成分分析提取出药效因子、高产因子、总黄酮因子和花径因子4个主成分,其累计贡献率为84.34%;综合评价得分排在前3位的依次为枣庄引种的红心菊、早小洋菊、滁菊。结合聚类分析结果,判定在原产地,滁州滁菊适于药用;在枣庄引种地,红心菊为优选的高产品种,早小洋菊为综合品质优良的品种。通过建立药用菊花品种产量和品质的综合评价体系,可为我国药茶两用菊花新品种的引种筛选和药食同源利用提供理论依据。

基于深度主动学习与CBAM的细粒度菊花表型识别

针对菊花种类繁多,花型差别细微,准确标注比较困难的问题,基于深度主动学习与混合注意力机制模块(Convolutional block attention module,CBAM),提出了一种标号数据不足情况下的菊花表型智能识别方法和框架。首先,通过主动学习策略基于最优标号和次优标号法(Best vs second-best,BvSB)在未标记菊花样本中选取信息量较大的样本进行标记,并将标记后的样本放入训练样本中;其次,使用深度卷积神经网络ResNet50作为本文的主干网络训练标记样本,引入混合注意力机制模块CBAM,使模型能够更为准确地提取细粒度图像中的高层语义信息;最后,用更新后的训练样本继续训练分类模型,直到模型达到迭代次数后停止。实验结果表明,该方法在少量菊花标记样本下,精确率、召回率和F1值分别达到93.66%、93.15%和93.41%。本文方法可为标号数据不足情况下的菊花等花卉智能化识别提供技术支撑。

不同直插型基质对3种盆栽菊花生长的影响以及综合评价

为提高盆栽菊花(Chrysanthemum morifolium)扦插繁殖的成活率,提高菊花生产效率,以既有扦插基质又有营养基质的直插型基质代替传统栽培基质,设置了12种不同扦插基质,配合前期筛选的营养基质,扦插培养3种盆栽菊花‘辉煌’‘波尔多红’‘黄芙蓉’。测量其生长、生理以及光合指标,并利用主成分分析和隶属函数对不同直插型基质的盆栽菊花生长效果进行综合评价。结果表明:扦插基质为Z1(河沙)、Z2(珍珠岩)、Z3(蛭石)时,3个盆栽菊花品种的株高、茎粗、冠幅及花期等生长指标更具优势。‘辉煌’‘波尔多红’‘黄芙蓉’在Z2处理中的综合评价指数最高,分别为0.999、0.940、1.000,说明其育苗效果最好,可作为最佳直插型基质,其次为Z1、Z3处理。而扦插基质中,椰糠、稻壳和泥炭体积占比较大时,并不利于盆栽菊花的生长。

神农香菊R2R3-MYB转录因子CiMYB4在镉胁迫中的功能分析

为探究CiMYB4在镉胁迫下的功能,以课题组已获得的过表达CiMYB4烟草(CiMYB4-S)、野菊(CiMYB4-OE)和抑制表达野菊(CiMYB4-Ri)为材料,在镉胁迫条件下分别测定其生长相关指标、抗氧化酶活性、光合指标、地上部及根系的镉含量,并对耐镉相关基因PCS1、GSH1、ABCC1、HMA3的表达模式进行分析。研究结果表明:镉处理后,CiMYB4-S和CiMYB4-OE株系的根长、茎粗、株高和叶长、叶宽显著大于野生型对照(WT)株系,丙二醛(MDA)含量显著降低,超氧化物歧化酶(SOD)、过氧化物酶(POD)、过氧化氢酶(CAT)活性显著增强,叶片的光合能力和叶绿素含量显著增加,具有更强的镉富集和转运能力。同时,耐镉相关基因PCS1、GSH1、HMA3的表达水平显著提高;而CiMYB4-Ri株系的株高、地上部干重显著小于WT株系,MDA含量显著增加,SOD、POD、CAT活性显著降低,叶片的光合能力和叶绿素含量显著降低,镉富集和转运能力减弱。同时,耐镉相关基因PCS1、GSH1、HMA3的表达水平显著降低。上述结果表明CiMYB4能提高烟草和野菊对镉的耐受性。

干旱胁迫对彩菊切花幼苗根系构型和生理活性的影响

以6个品种彩菊切花幼苗为试材,通过盆栽和人工浇灌20 mmol·L^(-1)浓度PEG 6000模拟干旱胁迫处理,探究彩菊切花在干旱胁迫第5、10、15、20天时根系构型和生理指标变化,选出抗旱性强、适应宁夏地区大面积推广与种植的优良彩菊切花品种,以期为西部干旱地区菊花品种的推广提供参考依据。结果表明:随着干旱胁迫的持续,彩菊切花的根系总长度、根系总表面积、根系总体积与总根系指标的关联程度较大。除根系总体积外,根系平均直径与其他根系指标不存在相关性。与正常浇水相比,不同品种彩菊切花的叶片相对含水量和叶绿素含量不断下降,相对电导率和可溶性蛋白质含量升高,丙二醛和可溶性糖含量先上升后下降,过氧化物酶活性呈先下降后上升趋势,超氧化物歧化酶活性呈先上升再下降最后上升的趋势。

Interaction between MAPKs and MKPs in hexaploid chrysanthemum illuminates functional paralogue diversification in polyploids

Mitogen-activated protein kinases(MAPKs,also known as MPKs)regulate diverse cellular and physiological functions,and dual-specificity MAPK phosphatases(MKPs)modulate MAPK signalling through MAPK dephosphorylation and inactivation.Due to lacking of overall understanding for the regulatory networks between Chrysanthemum morifolium MKPs(CmMKPs)and C.morifolium MAPKs(CmMPKs),we systematically studied the interactions between four groups of CmMPKs and eight identified CmMKPs in chrysanthemum and found that the interaction between the specific CmMKP and the specific CmMPK differed from those in other plants.Furthermore,the expression of CmMKP1 and CmMKP1-LIKE1showed opposite trends during the development of chrysanthemum flower buds under salt treatment and Alternaria alternata inoculation,but these genes could interact with the same CmMPKs,providing insight into the subfunctionalization of paralogues.Amino acid variations(M87V,T277P and V6L)in dual-specificity protein phosphatases(DsPTP1)-LIKE1/2/3 changed the interactions of these proteins with the four CmMPK groups in chrysanthemum,providing evidence for the de/neofunctionalization of paralogues in polyploids,suggesting that we can identify the key functional sites of proteins by studying polyploid paralogues.

Optimization of Extraction Process of Polyphenols from Chrysanthemum morifolium and the Development of Chrysanthemum Rice Wine

[Objectives]This study was conducted to provide a theoretical basis for the extraction and comprehensive utilization of functional active components of Chrysanthemum morifolium polyphenols.[Methods]With C.morifolium as a raw material,polyphenols were extracted by water extraction.The extraction process of polyphenols were optimized by single factor tests on solid-liquid ratio,extracting time and times.Old rice wine selected as the base wine was added with C.morifolium polyphenol extract,honey,citric acid and other auxiliary materials to prepare a kind of chrysanthemum old rice wine.Through sensory analysis combined with fuzzy mathematics comprehensive evaluation method,the optimal formula of chrysanthemum old rice wine was determined,and the corresponding physicochemical indicators of the obtained chrysanthemum old rice wine were tested.[Results]The optimal soaking process for C.morifolium was as follows:extraction time of 20 min,a solid-liquid ratio of C.morifolium to warm water at 1:40,extraction times of 3 times.The physical and chemical indicators of the chrysanthemum wine obtained from the above optimal formula were as follows:sugar content 5%,ethanol content 11%,and pH value 4.04.The chrysanthemum old rice wine obtained was clear and transparent,and the fragrance of chrysanthemum was coordinated with the mellow aroma of rice wine.The taste was refreshing and suitable for the vast majority of people to drink.[Conclusions]The new type of chrysanthemum old rice wine combines the polyphenolic active substances in C.morifolium with the low ethanol content of old rice wine,which not only improves the utilization rate of C.morifolium,but also strengthens the health function of old rice wine products,improves the quality of old rice wine,and promotes the healthy and rapid development of the old rice wine industry.

Comparative Non Participating Transcriptome Analysis Response to Low Phosphorus by CmPht1;2 in Chrysanthemum

Chrysanthemum morifolium Ramat is one of the four major cut flowers in the world.Pht1 family is focus on the uptake and transport of phosphate in plants.In our previous studies,CmPht1;2 overexpression line(Oe1)had higher phosphate contents both in roots and shoots,and its root development was significantly enhanced than wild type(WT)at low phosphorus conditions in chrysanthemum.Metabolomics analysis showed that several metabolites had a change in pyruvate metabolism and tricarboxylic acid(TCA)cycle pathway.To explore the gene difference expression and the change of metabolic pathway between CmPht1;2-Oe1 and WT,we conducted the transcriptome analysis.A total of 617,681 and 207,271 unigenes were obtained from roots and shoots,respectively.They were classified into biological process,cellular component and molecular function by Gene Ontology(GO).In addition,450 different expression genes(DEGs)were found in the roots after 2 d treatment,and 1,787 DEGs were identified in shoots after 7 d treatment under LP condition between Oe1 and WT.From the top 20 pathways of DEGs assigned by Kyoto Encyclopedia of Genes and Genomes(KEGG),TCA cycle and pyruvate metabolism pathways mostly affected by overexpression of CmPht1;2 attracted our attention.This research will be helpful for elucidating the mechanism of effects by CmPht1;2 overexpression on growth,development and stress tolerance.

B Class Floral Homeotic Genes are Involved in the Petal Identity and Flower Meristem Determinations in Chrysanthemum morifolium

Chrysanthemum morifolium,an ornamental crop with diverse forms of inflorescence,is a good model for studying flower development in Asteraceae.However,the genetic background is complex and the mechanisms of regulating flower development are still unclear.Here,we identified two natural mutant lines of chrysanthemum and named them M1 and M2 according to the severity of the phenotype.Both lines showed defects in petal identity,and the petals of the M1 line had a mild phenotype:partially loss of petal identity and conversion of petals into green,leaf-like organs.The M2 line had severe phenotypes:in addition to severe petal defects,secondary inflorescences were produced in the capitulum to replace the normal ray and disc florets,which indicated a transformation of a flower meristem into an inflorescence meristem.Transcriptome sequencing of WT and M2 inflorescences was performed and found altered expression of floral organ development A,B and E class genes,where B and E class genes were significantly down-regulated.qRT-PCR analysis in both M1 and M2 lines revealed that the expression of three chrysanthemum class B genes CmAP3.1,CmAP3.2 and CmPI,was negatively correlated with phenotypic severity.This suggests that class B genes in chrysanthemum not only have conserved functions in determining petal identity but also were involved in the determinacy of the flower meristem.This study provides insights into the functions of class B genes in flower development,and is informative for dissecting the molecular mechanisms of flower development in chrysanthemum.

怀菊花茎叶中聚炔类化合物对ox-LDL诱导的HUVECs细胞损伤的保护作用

研究怀菊花茎叶中分离得到的聚炔类化合物对氧化低密度脂蛋白(oxidized low density lipoprotein,ox-LDL)诱导的人脐静脉内皮细胞(human umbilical vein endothelial cells,HUVECs)损伤的保护作用及初步探讨作用机制。采用ox-LDL(200μg/mL)处理HUVECs细胞建立内皮细胞损伤模型,同时给予聚炔类化合物1~10(100μg/mL)干预;通过CCK-8法检测细胞生存率,筛选出有细胞保护作用的目标化合物;采用目标化合物5和9(12.5、25、50、100μg/mL)干预细胞24 h,CCK-8检测细胞生存率,采用流式细胞术检测细胞凋亡率和活性氧(reactive oxygen species,ROS)生成率,酶联免疫(ELISA)检测细胞上清液中白介素-1β(interleukin-1β,IL-1β)、白介素-6(interleukin-6,IL-6)及肿瘤坏死因子-α(tumor necrosis factor-α,TNF-α)含量;细胞免疫印迹法(In-Cell Western)检测细胞中核转录因子-κB(nuclear transcription factor-κB,NF-κB)2p100/p52与NF-κBp65蛋白的相对表达水平。结果显示:与正常对照组(Con)相比,模型组(ox-LDL)中的细胞生存率明显下降,细胞凋亡率、ROS生成,炎性因子IL-1β、IL-6及TNF-α明显升高(P<0.01);与ox-LDL组相比,聚炔类化合物5和9可以明显提高HUVECs细胞的生存率、降低细胞凋亡率、ROS生成率,炎性因子IL-1β、IL-6及TNF-α的分泌(P<0.05或P<0.01),下调NF-κB2 p100/p52、NF-κB p65蛋白的表达(P<0.05或P<0.01)。综上所述,怀菊花茎叶中聚炔苷类成分可以改善ox-LDL诱导的HUVECs细胞损伤与功能障碍,其作用机制可能与NF-κB信号通路相关。

野菊花水提物对RAW264.7炎症细胞模型的抗炎作用及其机制

目的建立以脂多糖(LPS)诱导的RAW 264.7巨噬细胞为模型,探讨野菊花提取液(CID)通过核转录因子(NF-κB)信号通路发挥抗炎活性的作用及其分子机制。方法以噻唑蓝(MTT)法检测不同浓度CID对RAW 264.7巨噬细胞活性的影响以筛选适宜的实验浓度;分别采用Griess法和酶联免疫吸附试验(ELISA)测定50、100、200μg·mL^(-1) CID干预后各组细胞中一氧化氮(NO)和肿瘤坏死因子-α(TNF-α)、白细胞介素-6(IL-6)的释放量;实时荧光定量聚合酶链式反应(RT-PCR)分析各组中环氧合酶-2(COX-2)和诱导型一氧化氮合酶(iNOS)mRNA的相对表达水平;免疫印迹实验(WB)观察各组中nuclear factor-kappa B p65(NF-κB p65)、inhibitor kappa B(IκB-α)和磷酸化IκB-α(p-IκB-α)的蛋白表达。结果50~200μg·mL^(-1)的CID可显著降低LPS诱导RAW264.7巨噬细胞中NO、TNF-α和IL-6的生成量(P<0.01),并能下调COX-2和iNOX mRNA的相对表达(P<0.01)、下调p-IκB-α、总的NF-κB p65、细胞核NF-κB p65的蛋白相对含量(P<0.01),并上调IκB-α、细胞质NF-κB p65的相对含量(P<0.01)。结论CID可有效降低LPS诱导RAW 264.7巨噬细胞的炎症因子释放,其机制可能与通过减少TNF-α等关键蛋白表达以及通过抑制NF-κB等炎症信号通路激活来抑制炎症发生有关。

A network pharmacology-based investigation of the mechanism of action of chrysanthemum in treating dry eye

Background:Dry eye is a chronic inflammatory disease of the ocular surface that is caused by multiple factors,characterized by pain,visual disturbance,and ocular damage.It is a common ophthalmic disease worldwide and a hot research field for scholars both domestically and internationally.This article employs network pharmacology methods to analyze the mechanism of Chrysanthemum in treating dry eye,which is a promising approach.Methods:The TCMSP(http://tcmspw.com/tcmsp.php)was used to screen for candidate active ingredient molecules of chrysanthemum with oral bioavailability≥30%and drug similarity to chrysanthemum≥0.18 as parameters.The active ingredients of chrysanthemum were searched using the“Related Targets”column in the TCMSP,followed by target prediction.Subsequently,Cytoscape 3.6.0 was employed to construct a compound-target network for chrysanthemum.The Online Mendelian Inheritance in Man and DisGeNET databases were used to identify pathogenic genes associated with dry eye.Furthermore,the STRING database was used to construct an interaction network and bar graph of intersecting target proteins in chrysanthemum to analyze protein interactions and core targets.To obtain key targets of active ingredients of chrysanthemum for treating dry eye,active ingredients targets of chrysanthemum and dry eye targets were intersected using Venny.Finally,a drug-active ingredient-key target-disease network was constructed.Gene Ontology functional annotation of key targets was performed using the WEBGESTALT database,and Kyoto Encyclopedia of Genes and Genomes pathway enrichment was performed using the REACTOM database.Results:Eighty active ingredients of chrysanthemum corresponding to targets were obtained.Among active ingredients,508 predicted targets were identified,along with 4180 genes associated with dry eye and 45 key targets of chrysanthemum for treating dry eye.The functions of key targets primarily include regulation of gene expression,oxidative stress,immune response,apoptosis,proliferation,regulation of cellular inflammation-related factors,and angiogenesis.The primary pathways associated with key targets include interleukin signaling,metabolism,cytokine signaling in the immune system,immune system,and signal transduction.Conclusion:Chrysanthemum facilitates regulation through multiple molecules,targets,and pathways for treating dry eye,primarily inhibiting inflammation-related factors and pathways,thereby reducing inflammation of lacrimal gland tissue and improving dry eye.

气相色谱-串联质谱法测定菊花中29种农药残留量的不确定度评价

为建立菊花中29种农药残留的气相色谱-串联质谱测定方法及不确定度评价,采用气相色谱-串联质谱内标法测定菊花中29种农药残留的含量,并依据测量不确定度的相关评定标准与表示,通过建立数学模型,对检测过程中产生的不确定度进行分析与评价,包括标准溶液配制、标准曲线拟合、供试品测定3大方面.结果表明:菊花中29种农药质量浓度在0.002~0.1 mg/L内线性关系良好,回归方程决定系数R2为0.997 36~0.999 82,定量限0.002 03~1.18 963 mg/L,检出限0.000 64~0.356 89 mg/L,添加回收实验中测定平均回收率为69.85%~93.26%,29种农药测量数值为0.04、0.06、0.1 mg/kg时,得到扩展不确定度为0.004 787~0.058 935 mg/kg.测量结果不确定度显示标准工作液的配制和标准曲线拟合是本实验测定方法不确定度的主要影响因素,该实验结果可以为测定菊花中农药残留量的方法及不确定度评价提供参考.

干旱胁迫对‘济菊’生长及光合生理特性的影响

设置正常水平、轻度干旱、中度干旱、重度干旱4个不同的控水梯度,研究不同干旱胁迫条件下‘济菊’生长指标及光合生理特性参数的变化,为其规范化栽培提供参考。随着干旱胁迫程度的加剧和时间的持续,植株的生物量、叶片的相对含水量呈下降趋势,叶绿素含量先上升后下降;光合速率、蒸腾速率、气孔导度和胞间二氧化碳浓度总体均呈下降趋势,但胞间二氧化碳浓度在重度干旱条件下有一个先升后降的过程;超氧化物歧化酶、过氧化物酶和过氧化氢酶的活性均呈先上升后下降趋势。重度干旱胁迫下‘济菊’可持续耐旱21 d以上,说明‘济菊’具有很强的抗旱性,同时也表明一定范围的干旱胁迫下,‘济菊’可以通过保护酶实现自我调节来维持生理代谢以适应干旱环境。

添加牛粪堆肥对盆栽菊花生长及抑菌效果的影响

以3个菊花品种(‘辉煌’‘波尔多红’‘黄芙蓉’)为试材,采用添加不同比例(栽培基质与牛粪堆肥的体积比分别为1∶1、3∶1、5∶1)的牛粪堆肥进行基质复配的方法开展育苗试验,研究添加不同体积牛粪堆肥对栽培基质的理化性质以及盆栽菊花的形态、生理指标以及抑菌效果的影响,以期降低盆栽菊花染病机率,提高其观赏性。结果表明:随牛粪堆肥占比增加,基质容重增加,碱解氮、有效磷和速效钾含量增加,pH上升,孔隙度降低,EC值变化不明显。基质中添加牛粪堆肥可以显著促进盆栽菊花株高的伸长、花茎增粗、冠幅增大、叶片生长。3种盆栽菊花在对照中病情指数最高,可溶性蛋白质含量最低。处理盆栽菊花的成活率均为100%。在Y1处理下‘辉煌’长势最好,‘波尔多红’和‘黄芙蓉’在Y3处理时长势最好。‘辉煌’在Y1、Y2处理中病情指数最低,‘波尔多红’和‘黄芙蓉’在Y3处理中病情指数最低,因此在基质中适量添加牛粪堆肥能够促进盆栽菊花生长,降低其患病机率。