Floral scent serves as a key criterion for evaluating the ornamental value of flowering plants.Herbaceous peony(Paeonia lactiflora Pall.),a traditional Chinese ornamental species,is valued for its vibrant coloration,i...Floral scent serves as a key criterion for evaluating the ornamental value of flowering plants.Herbaceous peony(Paeonia lactiflora Pall.),a traditional Chinese ornamental species,is valued for its vibrant coloration,intricate floral morphology,and positive cultural symbolism.In this study,dynamic headspace adsorption coupled with gas chromatography-mass spectrometry was employed to analyze volatile organic compounds(VOCs)in flowers of 120 herbaceous peony cultivars at the half-opening stage.We detected 86 VOCs,comprising 25 aromatic compounds(79.70%),21 hydrocarbons(10.51%),29 terpenoids(8.37%),7 fatty acid derivatives(1.03%),and 4 heterocyclic compounds(0.38%).The cultivar‘Dr.Alexander Fleming’demonstrated the highest total VOC content,followed by‘Yuezhao Shanhe’and‘Daiyu’.The top five cultivars based on principal component analysis composite scores were‘Shajin Guanding’,‘Many Happy Returns’,‘Edulis Superba’,‘Huicui’,and‘Madame de Verneville’.The volatile compositions of these cultivars showed statistically representative characteristics.Aroma activity value analysis revealed 22 key aroma components(e.g.,3-hexen-1-ol,acetate,(Z)-,limonene,(E)-β-ocimene)and 15 modifying components(e.g.,methyl hexanoate,α-pinene,benzaldehyde).Domestic cultivars exhibited greater VOC diversity and higher content levels compared to introduced cultivars,with introduced cultivars demonstrating more pronounced compositional variation.Introduced cultivars primarily released nonanal and 1,4-dimethoxybenzene,associated with fruity-sweet notes,whereas domestic cultivars predominantly released 1,4-dimethoxybenzene and phenylethanol,characterized by sweet-floral aromas.Aromatic compounds primarily contributed to the overall aroma,with terpenoids as secondary contributors.This study systematically characterized the floral aroma components of herbaceous peony,providing a theoretical foundation for germplasm resource utilization in cut flower production,essential oil extraction,and aromatherapy applications.展开更多
Floral color and scent are crucial for plant-environment interactions,especially in reproduction by attracting pollinators for fertilization.They also have wide applications in cosmetic,pharmaceutical,and nutraceutica...Floral color and scent are crucial for plant-environment interactions,especially in reproduction by attracting pollinators for fertilization.They also have wide applications in cosmetic,pharmaceutical,and nutraceutical industries.Plant pigments are typically classified as chlorophylls,flavonoids,carotenoids,and betalains,while volatile organic compounds(VOCs)are grouped as terpenes,phenylpropanoids/benzenoids,and fatty acid derivatives.Significant progresses have been made in understanding the biosynthesis and regulation of these floral pigments and VOCs.Despite differences in their biosynthetic pathways,floral pigments and VOCs are biochemically connected and exhibit synergistic interactions during flower development and in response to biotic and abiotic stresses,suggesting the existence of pleiotropic regulators or complex mechanisms co-regulating their biosynthesis.In this review,we summarize and outline the metabolite pathways mainly integrating flavonoids,carotenoids,terpenes,and phenylpropanoids/benzenoids.We also provide a series of scenarios illustrating the coordinated regulation of floral color and scent.Finally,we suggest areas for future research.We hope this review will spark interest in this research direction and stimulate further studies.展开更多
韩素音国际翻译大赛于1989年创办,是中国翻译界组织时间最长、规模最大、影响最广的翻译大赛,并受到全国乃至海外青年翻译爱好者的欢迎和认可。第37届韩素音翻译大赛的英译汉竞赛原文是“Scent Makes a Place”,汉译英竞赛原文是“中华...韩素音国际翻译大赛于1989年创办,是中国翻译界组织时间最长、规模最大、影响最广的翻译大赛,并受到全国乃至海外青年翻译爱好者的欢迎和认可。第37届韩素音翻译大赛的英译汉竞赛原文是“Scent Makes a Place”,汉译英竞赛原文是“中华优秀传统文化的生命力”。本文以语义翻译与交际翻译理论为基础,选择“第37届韩素音翻译大赛”汉英与英汉竞赛原文为研究对象,从词汇层面、句法层面和语篇层面三个维度出发,探讨第37届韩素音翻译大赛的翻译过程。此外,本研究基于语义翻译与交际翻译理论的核心理念,探索这些原则在翻译实践中的实际应用,并在其中涉及了多种翻译方法,例如直译、意译以及增译、减译等。经过深入研究,为了更好地翻译出竞赛的文本,需要在语义上要注重原文的形式和结构,强调对原作者创作意图的忠实再现。在交际上,唤起读者心理或情绪方面的效果,同时满足中文读者的阅读偏好。 .展开更多
Jasmine(Jasminum sambac Aiton)is a well-known cultivated plant species for its fragrant flowers used in the perfume industry and cosmetics.However,the genetic basis of its floral scent is largely unknown.In this study...Jasmine(Jasminum sambac Aiton)is a well-known cultivated plant species for its fragrant flowers used in the perfume industry and cosmetics.However,the genetic basis of its floral scent is largely unknown.In this study,using PacBio,Illumina,10×Genomics and highthroughput chromosome conformation capture(Hi-C)sequencing technologies,a high-quality chromosome-level reference genome for J.sambac was obtained,exploiting a double-petal phenotype cultivar‘Shuangbanmoli’(JSSB).The results showed that the final assembled genome of JSSB is 580.33 Mb in size(contig N50=1.05 Mb;scaffold N50=45.07 Mb)with a total of 39618 predicted protein-coding genes.Our analyses revealed that the JSSB genome has undergone an ancient whole-genome duplication(WGD)event at 91.68 million years ago(Mya).It was estimated that J.sambac diverged from the lineage leading to Olea europaea and Osmanthus fragrans about 28.8 Mya.On the basis of a combination of genomic,transcriptomic and metabolomic analyses,a range of floral scent volatiles and genes were identified involved in the benzenoid/phenylpropanoid and terpenoid biosynthesis pathways.The results provide new insights into the molecular mechanism of its fragrance biosynthesis in jasmine.展开更多
Manglietia ventii is a highly endangered plant species endemic to Yunnan province in China, where there are only five known small populations. Despite abundant flowering there is very low fruit and seed set,and very f...Manglietia ventii is a highly endangered plant species endemic to Yunnan province in China, where there are only five known small populations. Despite abundant flowering there is very low fruit and seed set,and very few seedlings in natural populations, indicating problems with reproduction. The causes of low fecundity in M. ventii are not known, largely because of insufficient knowledge of the species pollination ecology and breeding system. We conducted observations and pollination experiments, and analyzed floral scents to understand the pollinatoreplant interactions and the role of floral scent in this relationship, as well as the species breeding system. Like the majority of Magnoliaceae, M. ventii has protogynous and nocturnal flowers that emit a strong fragrance over two consecutive evenings. There is a closing period(the pre-staminate stage) during the process of anthesis of a flower, and we characterize the key flowering process as an "open-close-reopen" flowering rhythm with five distinct floral stages observed throughout the floral period of this species: pre-pistillate, pistillate, pre-staminate, staminate,and post-staminate. Flowers are in the pistillate stage during the first night of anthesis and enter the staminate stage the next night. During anthesis, floral scent emission occurs in the pistillate and staminate stages. The effective pollinators were weevils(Sitophilus sp.) and beetles(Anomala sp.), while the role of Rove beetles(Aleochara sp.) and thrips(Thrips sp.) in pollination of M. ventii appears to be minor or absent. The major chemical compounds of the floral scents were Limonene, b-Pinene, a-Pinene, 1,8-Cineole, Methyl-2-methylbutyrate, p-Cymene, Methyl-3-methyl-2-butenoate and 2-Methoxy-2-methyl-3-buten, and the relative proportions of these compounds varied between the pistillate and staminate stages. Production of these chemicals coincided with flower visitation by weevils and beetles.The results of pollination experiments suggest that M. ventii is pollinator-dependent, and low seed set in natural populations is a result of insufficient pollen deposition. Thus, conservation of the species should focus on improving pollination service through the introduction of genetically variable individuals and increase in density of reproducing trees.展开更多
Quantitative real-time PCR(qPCR)is an effective and widely used method to analyze expression patterns of target genes.Selection of stable reference genes is a prerequisite for accurate normalization of target gene exp...Quantitative real-time PCR(qPCR)is an effective and widely used method to analyze expression patterns of target genes.Selection of stable reference genes is a prerequisite for accurate normalization of target gene expression by qRT-PCR.In Iris germanica L.,no studies have yet been published regarding the evaluation of potential reference genes.In this study,nine candidate reference genes were assessed at different flower developmental stages and in different tissues by four different algorithms(GeNorm,NormFinder,BestKeeper,and RefFinder).The results revealed that ACT11(Actin 11)and EF1α(Elongation factor 1 alpha)were the most stable reference genes in different tissues,whereas TUA(Tubulin alpha)and UBC9(Ubiquitin-protein ligase 9)were the most stable ones in different flower developmental stages.UBC9 and ACT11 were the most stable reference genes in all of the tested samples,while the SAMDC(S-Adenosylmethionine decarboxylase)showed the least stability.Finally,to validate the suitability of the selected reference genes,the relative expression level of IgTPS(beta-caryophyllene synthase)was assessed and highlighted the importance of suitable reference gene selection.This work constitutes the first systematic evaluation of potential reference genes in I.germanica and provides guidelines for future research on gene function and molecular mechanisms on I.germanica and related species.展开更多
Male muskrats(Ondatra zibethicus L.)secrete musk from their scent glands during musk secretion season.Musk plays an important role as a communication pheromone during the breeding season.In this study,gas chromatogra...Male muskrats(Ondatra zibethicus L.)secrete musk from their scent glands during musk secretion season.Musk plays an important role as a communication pheromone during the breeding season.In this study,gas chromatography–mass spectrometry(GC–MS)was used to analyze the main components of musk.The GC–MS results after methyl esterification showed that 71.55%of the musk is composed of fatty acids.The other components of muskrat musk include cholesterol(9.31%)and other organics.Transcriptome comparison between musk secretion and non-secretion seasons showed significant changes in the scent glands for 53 genes involved in fatty acid and cholesterol synthesis and metabolism regulatory pathways,which include fatty acid biosynthesis,elongation,and metabolism;steroid biosynthesis;steroid hormone biosynthesis pathways.A reverse transcription–polymerase chain reaction analysis confirmed these detected changes.Overall,our results indicated that lipid synthesis and metabolism play important roles in musk compound synthesis by providing energy for musk production,and the produced musk provides a mechanism for male muskrats to communicate with females during the breeding season.展开更多
This paper presents the advantages of information foraging theory matched with traditional information retrieval theory and user behavior analysis theory, a search content framework for information foraging theory is ...This paper presents the advantages of information foraging theory matched with traditional information retrieval theory and user behavior analysis theory, a search content framework for information foraging theory is described, on a thor- ough review of the two research branches i.e. the basic concept of information foraging theory and the elementary mod- els of information foraging theory, an extended framework is proposed,. Several problems for future research are also identified through.展开更多
Syringa species are important ornamentals with strong floral scent,of which monoterpenes are the main component.In this study,a new monoterpene synthase gene,named SoLIM,was collected from the flowers of Syringa oblat...Syringa species are important ornamentals with strong floral scent,of which monoterpenes are the main component.In this study,a new monoterpene synthase gene,named SoLIM,was collected from the flowers of Syringa oblata and S.oblata var.alba using a homologous cloning method.The full-length cDNA of SoLIM was1746 bp and encoded 581 amino acids.Sequence analysis showed that SoLIM contained the DDxxD and RRx8 W motifs,which are two typical conserved monoterpene synthase motifs,and was thus classified as belonging to the Tpsb subfamily.Using quantitative reverse-transcription PCR,SoLIM was significantly expressed in the petals and pistils of S.oblata and S.oblata var.alba,respectively.SoLIM expression peaked earlier than the D-limonene emissions in the diurnal experiments,but occurred later when D-limonene had peaked during the flowering phase,indicating that differences in SoLIM gene expression and D-limonene emissions existed.The synthesis of floral scent is thus associated with diverse regulatory mechanisms that require further investigation.展开更多
Diversity analysis among 23 rice varieties including 16 non-basmati scented accessions, 5 basmati accessions and 2 non-scented accessions was performed by random amplified polymorphic DNA （RAPD） and inter-simple seq...Diversity analysis among 23 rice varieties including 16 non-basmati scented accessions, 5 basmati accessions and 2 non-scented accessions was performed by random amplified polymorphic DNA （RAPD） and inter-simple sequence repeat （ISSR） marker systems. The varieties analyzed by 11 RAPD and 8 ISSR primers yielded an average of 65% and 80% polymorphism, respectively. The average number of polymorphic bands generated per RAPD primer was 6 and per ISSR primer was 5.87. RAPD and ISSR data analysis individually could not segregate basmati and non-basmati scented rice accessions. However, the analysis using a combined data could group basmati and non-basmati scented rice accessions separately. The bands present specifically among three accessions of non-basmati scented rice were also identified. The study revealed a high genetic diversity among non-basmati scented rice accessions.展开更多
Preference for uninfected mates is presumed beneficial as it minimizes one＇s risk of contracting an infection and infecting one＇s offspring. In avian systems, visual ornaments are often used to indi- cate parasite b...Preference for uninfected mates is presumed beneficial as it minimizes one＇s risk of contracting an infection and infecting one＇s offspring. In avian systems, visual ornaments are often used to indi- cate parasite burdens and facilitate mate choice. However, in mammals, olfactory cues have been proposed to act as a mechanism allowing potential mates to be discriminated by infection status. The effect of infection upon mammalian mate choice is mainly studied in captive rodents where ex- perimental trials support preference for the odors of uninfected mates and some data suggest scent marking is reduced in individuals with high infection burdens. Nevertheless, whether such effects occur in nonmodel and wild systems remains poorly understood. Here, we investigate the interplay between parasite load （estimated using fecal egg counts） and scent marking behavior in a wild population of banded mongooses Mungos mungo. Focusing on a costly protozoan parasite of the genus Isospora and the nematode worm Toxocara, we first show that banded mongooses that engage in frequent, intensive scent marking have lower Isospora loads, suggesting marking behavior may be an indicator trait regarding infection status. We then use odor presentations to demonstrate that banded mongooses mark less in response to odors of opposite sexed individuals with high Isospora and Toxocara loads. As both of these parasites are known to have detrimental effects upon the health of preweaned young in other species, they would appear key targets to avoid during mate choice. Results provide support for scent as an important ornament and mechanism for advertising parasitic infection within wild mammals.展开更多
We studied the influences of immune activation by thymus-dependent(sheep red blood cells,SRBC)and independent(bacterial lipopolysaccharide,LPS)antigens on odor signals and endocrine status in dwarf hamsters.Administra...We studied the influences of immune activation by thymus-dependent(sheep red blood cells,SRBC)and independent(bacterial lipopolysaccharide,LPS)antigens on odor signals and endocrine status in dwarf hamsters.Administration of SRBS to mature males resulted in a drop of sexual scent attractiveness of soiled bedding collected during 5 days after injection.This effect was accompanied with a decline of fecal testosterone.Reduction of the male scent attractiveness after SRBC treatment had maximum manifestation in males of dwarf hamsters with low humoral immune response to this challenge.Contrary to the effects of SRBC,males injected with LPS showed an increase of scent attractiveness.Differences in the time that mature females spent sniffing olfactory stimuli(LPS vs control),correlated positively with differences in concentration of testosterone in feces collected from LPS and saline treated males.We discuss the adaptive meaning of the opposite olfactory effects,which induced by activation of the nonspecific innate immunity with LPS and by activation of specific acquired immunity with SRBC.展开更多
Previous studies have shown that individuals responded preferentially to the mark of the top-scent donor relative to that of the bottom-scent donor of an over-mark. However, terrestrial mammals are likely to encounter...Previous studies have shown that individuals responded preferentially to the mark of the top-scent donor relative to that of the bottom-scent donor of an over-mark. However, terrestrial mammals are likely to encounter over-marks consisting of the scent marks of more than two same-sex conspecifics in the intersections of runways, near the nests of sexually receptive female conspecifics, and inside and along the borders of the territories of conspecifics. We determined how meadow voles, Microtus pennsylvanicus, respond to the marks of the top-, middle-, and bottom-scent donors of an over-mark. We tested the hypothesis that voles exposed to an over-mark will respond preferentially to the scent marks that were deposited more recently, the scent marks that were on top or near the top of the over-mark, compared to the scent marks that were deposited earlier or near the bot- tom of the over-mark. Voles spent more time investigating the mark of the top-scent donor than that of the either the middle- or bottom-scent donor. However, males but not female voles spent more time investigating the middle-scent mark than the bot- tom-scent mark. We also tested the hypothesis that voles evaluate and respond to over-marks differently from single scent marks. Voles spent more time investigating the marks of the top-, middle-, and bottom-scent donors compared to scent marks that were not part of the over-mark. Voles can distinguish among the overlapping scent marks of three scent donors and sex differences exist in the values they appear to attach to each of these scent marks [Current Zoology 57 （4）： 441-448, 2011 ].展开更多
Many mammal species can distinguish between opposite-sex conspecifics that differ in a certain trait. In that coat coloration is associated with differences in physiological and behavioral traits, coat color may affec...Many mammal species can distinguish between opposite-sex conspecifics that differ in a certain trait. In that coat coloration is associated with differences in physiological and behavioral traits, coat color may affect the attractiveness of odor cues produced by conspecifics. Individuals may be able to respond preferentially to conspecifics with a particular coat color. In the present study, we test the hypothesis that scent marks of brown and blond voles differ in their attractiveness to male and fe- male conspecifics. Male voles and brown females did not discriminate between blond- and brown-coated opposite-sex con- specifics suggesting that they are neither selecting potential mates dissociatively nor associatively. However, blond females be- haved as if the scent marks of blond males were more attractive than were the scent marks of brown males. Our data suggest that blond females who are already conspicuous to predators, may select blond males as mates because they do not appreciably in- crease the risk of detection to predators, particularly avian predators. Moreover, because these conspicuous males have survived to mate they may have good genes that reflect their relatively higher quality展开更多
Odors that induce psychological orbehavioral changes in the same species——fright in a catfish^2,sexual arousal in abull—are called pheromones^3.And nowheredo such odors have more profound aneffect than among the be...Odors that induce psychological orbehavioral changes in the same species——fright in a catfish^2,sexual arousal in abull—are called pheromones^3.And nowheredo such odors have more profound aneffect than among the bees,wasps,ants,and termites^4:Pheromones are the chemicalmessages that these insects use to organizetheir complex societies.The queen honeybee preserves hermonarchy^5 by exuding^6 an odor thatnhibits worker bees from laying eggs展开更多
基金funded by the National Natural Science Foundation of China[grant number U23A20211]the Key Scientific Research Project of Higher Education Institutions in Henan Province[grant number 24A220001].
文摘Floral scent serves as a key criterion for evaluating the ornamental value of flowering plants.Herbaceous peony(Paeonia lactiflora Pall.),a traditional Chinese ornamental species,is valued for its vibrant coloration,intricate floral morphology,and positive cultural symbolism.In this study,dynamic headspace adsorption coupled with gas chromatography-mass spectrometry was employed to analyze volatile organic compounds(VOCs)in flowers of 120 herbaceous peony cultivars at the half-opening stage.We detected 86 VOCs,comprising 25 aromatic compounds(79.70%),21 hydrocarbons(10.51%),29 terpenoids(8.37%),7 fatty acid derivatives(1.03%),and 4 heterocyclic compounds(0.38%).The cultivar‘Dr.Alexander Fleming’demonstrated the highest total VOC content,followed by‘Yuezhao Shanhe’and‘Daiyu’.The top five cultivars based on principal component analysis composite scores were‘Shajin Guanding’,‘Many Happy Returns’,‘Edulis Superba’,‘Huicui’,and‘Madame de Verneville’.The volatile compositions of these cultivars showed statistically representative characteristics.Aroma activity value analysis revealed 22 key aroma components(e.g.,3-hexen-1-ol,acetate,(Z)-,limonene,(E)-β-ocimene)and 15 modifying components(e.g.,methyl hexanoate,α-pinene,benzaldehyde).Domestic cultivars exhibited greater VOC diversity and higher content levels compared to introduced cultivars,with introduced cultivars demonstrating more pronounced compositional variation.Introduced cultivars primarily released nonanal and 1,4-dimethoxybenzene,associated with fruity-sweet notes,whereas domestic cultivars predominantly released 1,4-dimethoxybenzene and phenylethanol,characterized by sweet-floral aromas.Aromatic compounds primarily contributed to the overall aroma,with terpenoids as secondary contributors.This study systematically characterized the floral aroma components of herbaceous peony,providing a theoretical foundation for germplasm resource utilization in cut flower production,essential oil extraction,and aromatherapy applications.
基金supported by the National Natural Science Foundation of China(Grant Nos.32272751,32272750,31972445)the Department of Science and Technology of Jilin Province(Grant Nos.20220508112RC,20210101005JC)+1 种基金the“Pioneer”and“Leading Goose”R&D Program of Zhejiang(Grant No.2023C02028)the China Scholarship Council(Grant No.202006625007)。
文摘Floral color and scent are crucial for plant-environment interactions,especially in reproduction by attracting pollinators for fertilization.They also have wide applications in cosmetic,pharmaceutical,and nutraceutical industries.Plant pigments are typically classified as chlorophylls,flavonoids,carotenoids,and betalains,while volatile organic compounds(VOCs)are grouped as terpenes,phenylpropanoids/benzenoids,and fatty acid derivatives.Significant progresses have been made in understanding the biosynthesis and regulation of these floral pigments and VOCs.Despite differences in their biosynthetic pathways,floral pigments and VOCs are biochemically connected and exhibit synergistic interactions during flower development and in response to biotic and abiotic stresses,suggesting the existence of pleiotropic regulators or complex mechanisms co-regulating their biosynthesis.In this review,we summarize and outline the metabolite pathways mainly integrating flavonoids,carotenoids,terpenes,and phenylpropanoids/benzenoids.We also provide a series of scenarios illustrating the coordinated regulation of floral color and scent.Finally,we suggest areas for future research.We hope this review will spark interest in this research direction and stimulate further studies.
文摘韩素音国际翻译大赛于1989年创办,是中国翻译界组织时间最长、规模最大、影响最广的翻译大赛,并受到全国乃至海外青年翻译爱好者的欢迎和认可。第37届韩素音翻译大赛的英译汉竞赛原文是“Scent Makes a Place”,汉译英竞赛原文是“中华优秀传统文化的生命力”。本文以语义翻译与交际翻译理论为基础,选择“第37届韩素音翻译大赛”汉英与英汉竞赛原文为研究对象,从词汇层面、句法层面和语篇层面三个维度出发,探讨第37届韩素音翻译大赛的翻译过程。此外,本研究基于语义翻译与交际翻译理论的核心理念,探索这些原则在翻译实践中的实际应用,并在其中涉及了多种翻译方法,例如直译、意译以及增译、减译等。经过深入研究,为了更好地翻译出竞赛的文本,需要在语义上要注重原文的形式和结构,强调对原作者创作意图的忠实再现。在交际上,唤起读者心理或情绪方面的效果,同时满足中文读者的阅读偏好。 .
基金financially supported by the National Natural Science Foundation of China(Grant No.31772338)the Basic Scientific Research Business Special Project of Jiangsu Academy of Agricultural Sciences(Grant No.0090756100ZX)。
文摘Jasmine(Jasminum sambac Aiton)is a well-known cultivated plant species for its fragrant flowers used in the perfume industry and cosmetics.However,the genetic basis of its floral scent is largely unknown.In this study,using PacBio,Illumina,10×Genomics and highthroughput chromosome conformation capture(Hi-C)sequencing technologies,a high-quality chromosome-level reference genome for J.sambac was obtained,exploiting a double-petal phenotype cultivar‘Shuangbanmoli’(JSSB).The results showed that the final assembled genome of JSSB is 580.33 Mb in size(contig N50=1.05 Mb;scaffold N50=45.07 Mb)with a total of 39618 predicted protein-coding genes.Our analyses revealed that the JSSB genome has undergone an ancient whole-genome duplication(WGD)event at 91.68 million years ago(Mya).It was estimated that J.sambac diverged from the lineage leading to Olea europaea and Osmanthus fragrans about 28.8 Mya.On the basis of a combination of genomic,transcriptomic and metabolomic analyses,a range of floral scent volatiles and genes were identified involved in the benzenoid/phenylpropanoid and terpenoid biosynthesis pathways.The results provide new insights into the molecular mechanism of its fragrance biosynthesis in jasmine.
基金Funding(No.U1302262)to W.B.Sun from the NSFC-Yunnan joint fund on key projectsSurvey and Germplasm Conservation of PSESP in Southwest China(2017e2020,2017FY100100)+1 种基金partly supported by the Young Academic and Technical Leader Raising Foundation of Yunnan Province(2015HB091)the Science and Technology Research Program of Kunming Institute of Botany,the Chinese Academy of Science(KIB2016005)to G.Chen
文摘Manglietia ventii is a highly endangered plant species endemic to Yunnan province in China, where there are only five known small populations. Despite abundant flowering there is very low fruit and seed set,and very few seedlings in natural populations, indicating problems with reproduction. The causes of low fecundity in M. ventii are not known, largely because of insufficient knowledge of the species pollination ecology and breeding system. We conducted observations and pollination experiments, and analyzed floral scents to understand the pollinatoreplant interactions and the role of floral scent in this relationship, as well as the species breeding system. Like the majority of Magnoliaceae, M. ventii has protogynous and nocturnal flowers that emit a strong fragrance over two consecutive evenings. There is a closing period(the pre-staminate stage) during the process of anthesis of a flower, and we characterize the key flowering process as an "open-close-reopen" flowering rhythm with five distinct floral stages observed throughout the floral period of this species: pre-pistillate, pistillate, pre-staminate, staminate,and post-staminate. Flowers are in the pistillate stage during the first night of anthesis and enter the staminate stage the next night. During anthesis, floral scent emission occurs in the pistillate and staminate stages. The effective pollinators were weevils(Sitophilus sp.) and beetles(Anomala sp.), while the role of Rove beetles(Aleochara sp.) and thrips(Thrips sp.) in pollination of M. ventii appears to be minor or absent. The major chemical compounds of the floral scents were Limonene, b-Pinene, a-Pinene, 1,8-Cineole, Methyl-2-methylbutyrate, p-Cymene, Methyl-3-methyl-2-butenoate and 2-Methoxy-2-methyl-3-buten, and the relative proportions of these compounds varied between the pistillate and staminate stages. Production of these chemicals coincided with flower visitation by weevils and beetles.The results of pollination experiments suggest that M. ventii is pollinator-dependent, and low seed set in natural populations is a result of insufficient pollen deposition. Thus, conservation of the species should focus on improving pollination service through the introduction of genetically variable individuals and increase in density of reproducing trees.
基金The work was supported by the National Natural Science Foundation of China(31801901)the Natural Science Foundation of Jiangsu(BK20180314)+1 种基金the Foundation of Key Laboratory of Landscaping(KF201901),Ministry of Agriculture and Rural Affairs,Chinathe Jiangsu Key Laboratory for the Research and Utilization of Plant Resources(JSPKLB201814).
文摘Quantitative real-time PCR(qPCR)is an effective and widely used method to analyze expression patterns of target genes.Selection of stable reference genes is a prerequisite for accurate normalization of target gene expression by qRT-PCR.In Iris germanica L.,no studies have yet been published regarding the evaluation of potential reference genes.In this study,nine candidate reference genes were assessed at different flower developmental stages and in different tissues by four different algorithms(GeNorm,NormFinder,BestKeeper,and RefFinder).The results revealed that ACT11(Actin 11)and EF1α(Elongation factor 1 alpha)were the most stable reference genes in different tissues,whereas TUA(Tubulin alpha)and UBC9(Ubiquitin-protein ligase 9)were the most stable ones in different flower developmental stages.UBC9 and ACT11 were the most stable reference genes in all of the tested samples,while the SAMDC(S-Adenosylmethionine decarboxylase)showed the least stability.Finally,to validate the suitability of the selected reference genes,the relative expression level of IgTPS(beta-caryophyllene synthase)was assessed and highlighted the importance of suitable reference gene selection.This work constitutes the first systematic evaluation of potential reference genes in I.germanica and provides guidelines for future research on gene function and molecular mechanisms on I.germanica and related species.
基金This work was supported by Beijing Municipal Natural Science Foundation(Grant No.5202016)Fundamental research funds for the central universities(Grant No.2019YC18).
文摘Male muskrats(Ondatra zibethicus L.)secrete musk from their scent glands during musk secretion season.Musk plays an important role as a communication pheromone during the breeding season.In this study,gas chromatography–mass spectrometry(GC–MS)was used to analyze the main components of musk.The GC–MS results after methyl esterification showed that 71.55%of the musk is composed of fatty acids.The other components of muskrat musk include cholesterol(9.31%)and other organics.Transcriptome comparison between musk secretion and non-secretion seasons showed significant changes in the scent glands for 53 genes involved in fatty acid and cholesterol synthesis and metabolism regulatory pathways,which include fatty acid biosynthesis,elongation,and metabolism;steroid biosynthesis;steroid hormone biosynthesis pathways.A reverse transcription–polymerase chain reaction analysis confirmed these detected changes.Overall,our results indicated that lipid synthesis and metabolism play important roles in musk compound synthesis by providing energy for musk production,and the produced musk provides a mechanism for male muskrats to communicate with females during the breeding season.
文摘This paper presents the advantages of information foraging theory matched with traditional information retrieval theory and user behavior analysis theory, a search content framework for information foraging theory is described, on a thor- ough review of the two research branches i.e. the basic concept of information foraging theory and the elementary mod- els of information foraging theory, an extended framework is proposed,. Several problems for future research are also identified through.
基金supported by the Project of Construction of Innovative Teams and Teacher Career Development for Universities and Colleges under Beijing Municipality(IDHT20180509)the National Natural Science foundation of China(31201645)+1 种基金the Beijing Municipal Natural Science Foundation(6172006)key project of Beijing Municipal Education Commission(KZ201510020021)
文摘Syringa species are important ornamentals with strong floral scent,of which monoterpenes are the main component.In this study,a new monoterpene synthase gene,named SoLIM,was collected from the flowers of Syringa oblata and S.oblata var.alba using a homologous cloning method.The full-length cDNA of SoLIM was1746 bp and encoded 581 amino acids.Sequence analysis showed that SoLIM contained the DDxxD and RRx8 W motifs,which are two typical conserved monoterpene synthase motifs,and was thus classified as belonging to the Tpsb subfamily.Using quantitative reverse-transcription PCR,SoLIM was significantly expressed in the petals and pistils of S.oblata and S.oblata var.alba,respectively.SoLIM expression peaked earlier than the D-limonene emissions in the diurnal experiments,but occurred later when D-limonene had peaked during the flowering phase,indicating that differences in SoLIM gene expression and D-limonene emissions existed.The synthesis of floral scent is thus associated with diverse regulatory mechanisms that require further investigation.
文摘Diversity analysis among 23 rice varieties including 16 non-basmati scented accessions, 5 basmati accessions and 2 non-scented accessions was performed by random amplified polymorphic DNA （RAPD） and inter-simple sequence repeat （ISSR） marker systems. The varieties analyzed by 11 RAPD and 8 ISSR primers yielded an average of 65% and 80% polymorphism, respectively. The average number of polymorphic bands generated per RAPD primer was 6 and per ISSR primer was 5.87. RAPD and ISSR data analysis individually could not segregate basmati and non-basmati scented rice accessions. However, the analysis using a combined data could group basmati and non-basmati scented rice accessions separately. The bands present specifically among three accessions of non-basmati scented rice were also identified. The study revealed a high genetic diversity among non-basmati scented rice accessions.
文摘Preference for uninfected mates is presumed beneficial as it minimizes one＇s risk of contracting an infection and infecting one＇s offspring. In avian systems, visual ornaments are often used to indi- cate parasite burdens and facilitate mate choice. However, in mammals, olfactory cues have been proposed to act as a mechanism allowing potential mates to be discriminated by infection status. The effect of infection upon mammalian mate choice is mainly studied in captive rodents where ex- perimental trials support preference for the odors of uninfected mates and some data suggest scent marking is reduced in individuals with high infection burdens. Nevertheless, whether such effects occur in nonmodel and wild systems remains poorly understood. Here, we investigate the interplay between parasite load （estimated using fecal egg counts） and scent marking behavior in a wild population of banded mongooses Mungos mungo. Focusing on a costly protozoan parasite of the genus Isospora and the nematode worm Toxocara, we first show that banded mongooses that engage in frequent, intensive scent marking have lower Isospora loads, suggesting marking behavior may be an indicator trait regarding infection status. We then use odor presentations to demonstrate that banded mongooses mark less in response to odors of opposite sexed individuals with high Isospora and Toxocara loads. As both of these parasites are known to have detrimental effects upon the health of preweaned young in other species, they would appear key targets to avoid during mate choice. Results provide support for scent as an important ornament and mechanism for advertising parasitic infection within wild mammals.
文摘We studied the influences of immune activation by thymus-dependent(sheep red blood cells,SRBC)and independent(bacterial lipopolysaccharide,LPS)antigens on odor signals and endocrine status in dwarf hamsters.Administration of SRBS to mature males resulted in a drop of sexual scent attractiveness of soiled bedding collected during 5 days after injection.This effect was accompanied with a decline of fecal testosterone.Reduction of the male scent attractiveness after SRBC treatment had maximum manifestation in males of dwarf hamsters with low humoral immune response to this challenge.Contrary to the effects of SRBC,males injected with LPS showed an increase of scent attractiveness.Differences in the time that mature females spent sniffing olfactory stimuli(LPS vs control),correlated positively with differences in concentration of testosterone in feces collected from LPS and saline treated males.We discuss the adaptive meaning of the opposite olfactory effects,which induced by activation of the nonspecific innate immunity with LPS and by activation of specific acquired immunity with SRBC.
文摘Previous studies have shown that individuals responded preferentially to the mark of the top-scent donor relative to that of the bottom-scent donor of an over-mark. However, terrestrial mammals are likely to encounter over-marks consisting of the scent marks of more than two same-sex conspecifics in the intersections of runways, near the nests of sexually receptive female conspecifics, and inside and along the borders of the territories of conspecifics. We determined how meadow voles, Microtus pennsylvanicus, respond to the marks of the top-, middle-, and bottom-scent donors of an over-mark. We tested the hypothesis that voles exposed to an over-mark will respond preferentially to the scent marks that were deposited more recently, the scent marks that were on top or near the top of the over-mark, compared to the scent marks that were deposited earlier or near the bot- tom of the over-mark. Voles spent more time investigating the mark of the top-scent donor than that of the either the middle- or bottom-scent donor. However, males but not female voles spent more time investigating the middle-scent mark than the bot- tom-scent mark. We also tested the hypothesis that voles evaluate and respond to over-marks differently from single scent marks. Voles spent more time investigating the marks of the top-, middle-, and bottom-scent donors compared to scent marks that were not part of the over-mark. Voles can distinguish among the overlapping scent marks of three scent donors and sex differences exist in the values they appear to attach to each of these scent marks [Current Zoology 57 （4）： 441-448, 2011 ].
文摘Many mammal species can distinguish between opposite-sex conspecifics that differ in a certain trait. In that coat coloration is associated with differences in physiological and behavioral traits, coat color may affect the attractiveness of odor cues produced by conspecifics. Individuals may be able to respond preferentially to conspecifics with a particular coat color. In the present study, we test the hypothesis that scent marks of brown and blond voles differ in their attractiveness to male and fe- male conspecifics. Male voles and brown females did not discriminate between blond- and brown-coated opposite-sex con- specifics suggesting that they are neither selecting potential mates dissociatively nor associatively. However, blond females be- haved as if the scent marks of blond males were more attractive than were the scent marks of brown males. Our data suggest that blond females who are already conspicuous to predators, may select blond males as mates because they do not appreciably in- crease the risk of detection to predators, particularly avian predators. Moreover, because these conspicuous males have survived to mate they may have good genes that reflect their relatively higher quality
文摘Odors that induce psychological orbehavioral changes in the same species——fright in a catfish^2,sexual arousal in abull—are called pheromones^3.And nowheredo such odors have more profound aneffect than among the bees,wasps,ants,and termites^4:Pheromones are the chemicalmessages that these insects use to organizetheir complex societies.The queen honeybee preserves hermonarchy^5 by exuding^6 an odor thatnhibits worker bees from laying eggs
