Parasitic plants and their hosts communicate through haustorial connections.Nutrient deficiency is a common stress for plants,yet little is known about whether and how host plants and parasites communicate during adap...Parasitic plants and their hosts communicate through haustorial connections.Nutrient deficiency is a common stress for plants,yet little is known about whether and how host plants and parasites communicate during adaptation to such nutrient stresses.In this study,we used transcriptomics and proteomics to analyze how soybean(Glycine max)and its parasitizing dodder(Cuscuta australis)respond to nitrate and phosphate deficiency(-N and-P).After-N and-P treatment,the soybean and dodder plants exhibited substantial changes of transcriptome and proteome,although soybean plants showed very few transcriptional responses to-P and dodder did not show any transcriptional changes to either-N or-P.Importantly,large-scale interplant transport of mRNAs and proteins was detected.Although the mobile mRNAs only comprised at most 0.2%of the transcriptomes,the foreign mobile proteins could reach 6.8%of the total proteins,suggesting that proteins may be the major forms of interplant communications.Furthermore,the interplant mobility of macromolecules was specifically affected by the nutrient regimes and the transport of these macromolecules was very likely independently regulated.This study provides new insight into the communication between host plants and parasites under stress conditions.展开更多
than 80 Dendrobium species have been reported in China.However,there are only six Dendrobium species,namely,D.bigibbum var.superbum(syn.D.phalaenopsis),D.chrysanthum,D.fimbriatum,D.loddigesii,D.nobile,and D.officinale...than 80 Dendrobium species have been reported in China.However,there are only six Dendrobium species,namely,D.bigibbum var.superbum(syn.D.phalaenopsis),D.chrysanthum,D.fimbriatum,D.loddigesii,D.nobile,and D.officinale(syn.D.candidum),listed in the New Inventory of Existing Cosmetic Ingredients in China Launched.Artificial planting of Dendrobium species has been a great success in China.To better utilize Dendrobium resources for medicinal and cosmetic purposes,we summarize their traditional uses and pharmacologically active compounds for treating dermatological disorders in this review.“Orchidaceae”,“Dendrobium”,“traditional use”,“ethnobotany”,“dermatological disorder”,and“skin disease”were used as search terms to screen the literature.Cited references were collected between 1970 and 2020 from the Web of Science,China National Knowledge Internet(CNKI),SciFinder,Google Scholar,and Chinese books.From the search,it was found that there are 22 Dendrobium species with traditional uses in dermatological disorders,and 131 compounds from Dendrobium plants have been reported to possess anti-inflammatory,antimicrobial,antioxidant,antiaging,anti-psoriasis,and tyrosinase-inhibitory activities,implying that Dendrobium plants are important resources for the discovery of active compounds and the development of new drugs and cosmetics.D.crepidatum,D.denneanum,D.loddigesii,D.nobile,and D.officinale have been extensively studied.More research on other Dendrobium species is needed.The major active compounds found in Dendrobium species are phenanthrenes,alkaloids,flavonoids,phenylpropanoids,and lignans.Several compounds,such as loddigesiinol A,(S)-5-methoxy-2,4,7,9-tetrahydroxy-9,10-dihydrophenanthrene,(S)-4-methoxy-2,5,7,9-tetrahydroxy-9,10-dihydrophenanthrene,2,5-dihydroxy-4-methoxy-phenanthrene 2-O-β-d-glucopyranoside,(9R)-1,2,5,9-tetrahydroxy-9,10-dihydrophenanthrene 5-O-β-d-glucopyranoside,(+)-homocrepidine A,and vicenin 2,have significant anti-inflammatory activities and inhibit nitric oxide(NO)production with IC_(50) values less than 5μM,and these compounds are worthy of further study.展开更多
In the Qinba mountainous area of Central China,pig farming has a significant impact on the growth of the rural economy and has substantially increased farmer incomes.Traditional knowledge plays an important role in th...In the Qinba mountainous area of Central China,pig farming has a significant impact on the growth of the rural economy and has substantially increased farmer incomes.Traditional knowledge plays an important role in the selection of forage plant species for pig farming by local people.This study aimed to identify the forage plants used for pig feeding and to catalog indigenous knowledge regarding their use.During 2016 and 2017,ethnobotanical surveys and inventories were conducted in Zhuxi County,Hubei Province,China.Data were collected using semi-structured interviews,key informant reports,free listings,guided field walks,and participatory observations with 77 households in 16 villages in 13 towns/townships.The obtained data were analyzed using a relative frequency citation(RFC)index.Overall,145 wild forage plants from 91 genera and 31 families were recorded.The most cited families were Asteraceae,Polygonaceae,Urticaceae,Amaranthaceae,Fabaceae,Cruciferae,Caryophyllaceae,and Lamiaceae.Whole plants(75.9%)and tender leaves(12.4%)were the most frequently used parts of the plants.Most of the forage plants were herbaceous(88.9%).Almost all forage plants could be collected throughout the year(62.7%).Raw and cooked were the two main preparation methods.The most frequently cited species were Taraxacum mongolicum,Bidens pilosa,Sonchus oleraceus,Pilea verrucosa,and Pilea pumila var.obtusifolia.A total of 14 species were identified as the top forage plants in Zhuxi County based on their RFC values(RFC value greater than 0.5).Local people possess rich traditional knowledge about the utilization and management of forage plants for pig feeding.However,the maintenance of this traditional knowledge may be seriously threatened by changes in pig feeding modes and the lack of successors.Appropriate strategies and action plans have been suggested for the conservation of traditional knowledge associated with biodiversity and the sustainable use of forage species resources.These include 1)taking targeted measures to protect forage resources and associated traditional knowledge;2)strengthening research on the forage plants with the highest RFC values for nutritional value,digestibility,other functions,and ecological status;and 3)enhancing the identification of poisonous forage plants.展开更多
Haustorium formation is the characteristic feature of all parasitic plants and a vital process for successful parasitism.Previous investigations on haustorium initiation and development are constricted to induced proc...Haustorium formation is the characteristic feature of all parasitic plants and a vital process for successful parasitism.Previous investigations on haustorium initiation and development are constricted to induced processes by host-derived signals or synthetic analogs.Spontaneous haustorium formation in the absence of host signals,a process representing an early stage in the evolution of parasitic plants,remains largely unexplored.Lack of fast and frequent formation of spontaneous haustoria greatly hinders full understanding of haustorium formation in root hemiparasites.In this study,seedlings of Pedicularis kansuensis Maxim.,a facultative root hemiparasitic species in Orobanchaceae observed to produce many spontaneous haustoria,were grown in autoclaved water agar in the absence of any known haustoriuminducing stimulants.We aimed to test the temporal and developmental pattern of spontaneous haustorium formation.Also,effects of sucrose supply and root contact on spontaneous haustorium formation were tested.Spontaneous haustoria were observed starting from six days after germination,much earlier than previously reported root hemiparasites.A majority of the spontaneous haustoria formed on lateral roots.Percentage of seedlings with spontaneous haustoria was 28.8% when grown on water agar plates,with a mean of four haustoria per seedling two weeks after germination.Haustorium formation by seedlings grown in water agar amended with 2% sucrose was more than twice of those without sucrose amendment.Singly grown seedlings were able to develop spontaneous haustoria at similar levels as those grown with another conspecific seedling.In view of the fast and abundant formation of spontaneous haustoria,P.kansuensis may be developed as an excellent experimental system in future investigations for unraveling endogenous regulation of haustorium initiation and development in root hemiparasitic plants.展开更多
Compared with traditional genetic markers,genomic approaches have proved valuable to the conservation of endangered species.Paeonia ludlowii having rarely and pure yellow flowers,is one of the world’s most famous tre...Compared with traditional genetic markers,genomic approaches have proved valuable to the conservation of endangered species.Paeonia ludlowii having rarely and pure yellow flowers,is one of the world’s most famous tree peonies.However,only several wild populations remain in the Yarlung Zangbo Valley(Nyingchi and Shannan regions,Xizang)in China due to increasing anthropogenic impact on the natural habitats.We used genome-wide single nucleotide polymorphisms to elucidate the spatial pattern of genetic variation,population structure and demographic history of P.ludlowii from the fragmented region comprising the entire range of this species,aiming to provide a basis for conserving the genetic resources of this species.Unlike genetic uniformity among populations revealed in previous studies,we found low but varied levels of intra-population genetic diversity,in which lower genetic diversity was detected in the population in Shannan region compared to those in Nyingzhi region.These spatial patterns may be likely associated with different population sizes caused by micro-environment differences in these two regions.Additionally,low genetic differentiation among populations(Fst=0.0037)were detected at the species level.This line of evidence,combined with the result of significant genetic differentiation between the two closest populations and lack of isolation by distance,suggested that shared ancestry among now remnant populations rather than contemporary genetic connectivity resulted in subtle population structure.Demographic inference suggested that P.ludlowii probably experienced a temporal history of sharp population decline during the period of Last Glacial Maximum,and a subsequent bottleneck event resulting from prehistoric human activities on the Qinghai-Tibet Plateau.All these events,together with current habitat fragment and excavation might contribute to the endangered status of P.ludlowii.Our study improved the genetic characterization of the endangered tree peony(P.ludlowii)in China,and these genetic inferences should be considered when making different in situ and ex situ conservation actions for P.ludlowii in this evolutionary hotspot region.展开更多
Dendrobium nobile is an important medicinal and nutraceutical herb.Although the ingredients of D.nobile have been identified as polysaccharides,alkaloids,amino acids,flavonoids and bibenzyls,our understanding of the m...Dendrobium nobile is an important medicinal and nutraceutical herb.Although the ingredients of D.nobile have been identified as polysaccharides,alkaloids,amino acids,flavonoids and bibenzyls,our understanding of the metabolic pathways that regulate the synthesis of these compounds is limited.Here,we used transcriptomic and metabolic analyses to elucidate the genes and metabolites involved in the biosynthesis of carbohydrate and several secondary metabolites in the stems of D.nobile.A total of 1005 metabolites and 31,745 genes were detected in the stems of D.nobile.The majority of these metabolites and genes were involved in the metabolism of carbohydrates(fructose,mannose,glucose,xylulose and starch),while some were involved in the metabolism of secondary metabolites(alkaloids,β-tyrosine,ferulic acid,4-hydroxybenzoate and chrysin).Our predicted regulatory network indicated that five genes(AROG,PYK,DXS,ACEE and HMGCR) might play vital roles in the transition from carbohydrate to alkaloid synthesis.Correlation analysis identified that six genes(ALDO,PMM,BGLX,EGLC,XYLB and GLGA) were involved in carbohydrate metabolism,and two genes(ADT and CYP73A) were involved in secondary metabolite biosynthesis.Our analyses also indicated that phosphoenol-pyruvate(PEP) was a crucial bridge that connected carbohydrate to alkaloid biosynthesis.The regulatory network between carbohydrate and secondary metabolite biosynthesis established will provide important insights into the regulation of metabolites and biological systems in Dendrobium species.展开更多
Investigation of the relationships of phenotypic and epigenetic variations might be a good way to dissect the genetic or molecular basis of phenotypic variation and plasticity in plants. Castor bean(Ricinus communis L...Investigation of the relationships of phenotypic and epigenetic variations might be a good way to dissect the genetic or molecular basis of phenotypic variation and plasticity in plants. Castor bean(Ricinus communis L.), an important non-edible oilseed crop, is a mono-species genus plant in the family Euphorbiaceae. Since it displays rich phenotypic variations with low genetic diversity, castor bean is a good model to investigate the molecular basis of phenotypic and epigenetic variations. Cytosine DNA methylation represents a major molecular mechanism of epigenetic occurrence. In this study, epigenetic diversity of sixty landrace accessions collected worldwide was investigated using the methylationsensitive amplification polymorphism(MSAP) technique. Results showed that the epigenetic diversity(based on the polymorphism of DNA methylated loci) exhibited a medium variation(Ne=1.395,He=0.242,I=0.366) at the population level though the variation was great, ranging from 3.80% to 34.31% among accessions. Both population structure analysis and the phylogenetic construction(using the neighbor-joining criteria) revealed that the two main clades were identified, but they did not display a distinct geographic structure. After inspecting the location of polymorphic methylated loci on genome we identified that the polymorphic methylated loci occur widely in nuclear and organelle genomes. This study provides new data to understand phenotypic and epigenetic variations in castor bean.展开更多
Fertilization has been shown to have suppressive effects on arbuscular mycorrhizal fungi(AMF) and root hemiparasites separately in numerous investigations, but its effects on AMF in the presence of root hemiparasites ...Fertilization has been shown to have suppressive effects on arbuscular mycorrhizal fungi(AMF) and root hemiparasites separately in numerous investigations, but its effects on AMF in the presence of root hemiparasites remain untested. In view of the contrasting nutritional effects of AMF and root hemiparasites on host plants, we tested the hypothesis that fertilization may not show strong suppressive effects on AMF when a plant community was infested by abundant hemiparasitic plants. Plants and soil samples were collected from experimental field plots in Bayanbulak Grassland, where N and P fertilizers had been applied for three continuous years for control against a spreading root hemiparasite, Pedicularis kansuensis. Shoot and root biomass of each plant functional group were determined. Root AMF colonization levels, soil spore abundance, and extraradical hyphae length density were measured for three soil depths(0 e10 cm, 10 e20 cm, 20 e30 cm). Partial 18 S r RNA gene sequencing was used to detect AMF diversity and community composition. In addition, we analyzed the relationship between relative abundance of different AMF genera and environmental factors using Spearman's correlation method. In contrast to suppressive effects reported by many previous studies, fertilization showed no significant effects on AMF root colonization or AMF species diversity in the soil. Instead, a marked increase in soil spore abundance and extraradical hyphae length density were observed. However, fertilization altered relative abundance and AMF composition in the soil. Our results support the hypothesis that fertilization does not significantly influence the abundance and diversity of AMF in a plant community infested by P. kansuensis.展开更多
Zingiber cassumunar is an important plant used in traditional medicine and as a natural mosquito re-pellent.However,the compounds responsible for the repellent activity of the plant are still unknown.The aim of the st...Zingiber cassumunar is an important plant used in traditional medicine and as a natural mosquito re-pellent.However,the compounds responsible for the repellent activity of the plant are still unknown.The aim of the study is to identify the components of Z.cassumunar essential oil that show repellent activity against Aedes albopictus.We also evaluated the larvicidal and adulticidal activities of Z.cassumunar essential oil against Ae.albopictus.In-cage mosquito repellent experiments showed that Z.cassumunar essential oil possessed moderate repellent activity with a minimum effective dose(MED)of 0.16±0.01 mg/cm^(20,compared to reference standard N,N-diethyl-3-methylbenzamide(DEET,0.03±0.01 mg/cm^(20).Bioassay-guided fractionation identified the major active compound of Z.cassumunar essential oil as(-)-terpinen-4-ol(1)(MED:0.19±0 mg/cm^(20).We also found that Z.cassumunar essential oil showed moderate larvicidal activity against first instar larvae of Ae.albopictus with a LC50(50%lethal concentration)of 44.9 mg/L after 24 h.Fumigation bioassays showed that Z.cassumunar essential oil exhibits moderate adulticidal activity against Ae.albopictus with a LC50 of 5.44%,while(-)-terpinen-4-ol showed significant adulticidal activity with a LC50 of 2.10%after 24 h.This study verifies that the Z.cassumunar essential oil has mosquito repellent activity,and that(-)-terpinen-4-ol is mainly responsible for this activity.Furthermore,this study provides scientific support for the folk usage of Z.cassumunar essential oil as mosquito repellent and indicates that Z.cassumunar essential oil and(-)-terpinen-4-ol can be used as plant-derived repellents and insecticides for mosquito control.展开更多
mRNAs are transported within a plant through phloem.Aphids are phloem feeders and dodders(Cuscuta spp.)are parasites which establish phloem connections with host plants.When aphids feed on dodders,whether there is tra...mRNAs are transported within a plant through phloem.Aphids are phloem feeders and dodders(Cuscuta spp.)are parasites which establish phloem connections with host plants.When aphids feed on dodders,whether there is trafficking of mRNAs among aphids,dodders,and host plants and if aphid feeding a匚fects the mRNA transfer between dodders and hosts are unclear.We constructed a green peach aphid(GPA,Myzus persicae)-dodder(Cuscuta austra/is)-cucumber(Cucumis sativus)tritrophic system by infesting GPAs on C.australis,which parasitized cucumber hosts.We found that GPA feeding activated defense-related phytohormonal and transcriptomic responses in both C.australis and cucumbers and large numbers of mRNAs were found to be transferred between C.australis and cucumbers and between C.australis and GPAs;importantly,GPA feeding on C.australis greatly altered inter-species mobile mRNA profiles.Furthermore,three cucumber mRNAs and three GPA mRNAs could be respectively detected in GPAs and cucumbers.Moreover,our statistical analysis indicated that mRNAs with high abundances and long transcript lengths are likely to be mobile.This study reveals the existence of inter-species and even inter-kingdom mRNA movement among insects,parasitic plants,and parasite hosts,and suggests complex regulation of mRNA trafficking.展开更多
Hematophagous invertebrates such as mosquitoes,leeches,mites,ticks,lice and bugs cause various problems for humans.Considering reports on insecticide resistance and requirements for improved environmental and toxicolo...Hematophagous invertebrates such as mosquitoes,leeches,mites,ticks,lice and bugs cause various problems for humans.Considering reports on insecticide resistance and requirements for improved environmental and toxicological profiles,there is a continuing need to discover and develop new insecticides and repellents.Ethnobotanical surveys of traditional plant-based repellents provide a direct method of identifying plants for potential use.During five field surveys in Bulang,Jinuo and Lahu villages between August 2018 and July 2019,semi-structured interviews were conducted with 237 informants(151 male,86 female;mean age 63).Frequency of citation,use value,informant consensus factor and Jaccard index were employed to statistically analyze the collected data.A total of 709 use reports relating to 32 plant species and 71 remedies were collected.Similarities and differences between the three groups,as well as the Dai and Hani of Xishuangbanna,who were studied earlier,were shown through network analysis.These five ethnic groups living in the same area have a common understanding of traditional botanical knowledge against hematophagous invertebrates,but each group also possesses unique knowledge.Recording and protecting this traditional knowledge is potentially useful for protecting this cultural diversity and related biodiversity and can also have important practical applications.In this study,traditional knowledge provided us with many new potential plants for follow-up research for the development of new insecticides and repellents,among which Artemisia indica,Nicotiana tabacum and Clausena excavata are the most promising.展开更多
The evolution of photosynthesis is an important feature of mixotrophic plants.Previous inferences proposed that mixotrophic taxa tend to retain most genes relating to photosynthetic functions but vary in plastid gene ...The evolution of photosynthesis is an important feature of mixotrophic plants.Previous inferences proposed that mixotrophic taxa tend to retain most genes relating to photosynthetic functions but vary in plastid gene content.However,no sequence data are available to test this hypothesis in Ericaceae.To investigate changes in plastid genomes that may result from a transition from autotrophy to mixotrophy,the plastomes of two mixotrophic plants,Pyrola decorata and Chimaphila japonica,were sequenced at Illumina's Genome Analyzer and compared to the published plastome of the autotrophic plant Rhododendron simsii,which also belongs to Ericaceae.The greatest discrepancy between mixotrophic and autotrophic plants was that ndh genes for both P.decorata and C.japonica plastomes have nearly all become pseudogenes.P.decorata and C.japonica also retained all genes directly involved in photosynthesis under strong selection.The calculated rate of nonsynonymous nucleotide substitutions and synonymous substitutions of protein-coding genes(dN/dS) showed that substitution rates in shade plants were apparently higher than those in sunlight plants.The two mixotrophic plastomes were generally very similar to that of non-parasitic plants,although ndh genes were largely pseudogenized.Photosynthesis genes under strong selection were retained in the two mixotrophs,however,with greatly increased substitution rates.Further research is needed to gain a clearer understanding of the evolution of autotrophy and mixotrophy in Ericaceae.展开更多
Astaxanthin is a value-added ketocarotenoid with great potential in nutraceutical and pharmaceutical industries.Genetic engineering of heterologous hosts for astaxanthin production has attracted great attention.In thi...Astaxanthin is a value-added ketocarotenoid with great potential in nutraceutical and pharmaceutical industries.Genetic engineering of heterologous hosts for astaxanthin production has attracted great attention.In this study,we assessed some key factors,including codon usage of the expressed genes,types of promoters,bacterial strains,and culture media,for engineered Escherichia coli to produce astaxanthin.The effect of codon usage was shown to be related to the types of promoters.E.coli DH5a was superior to other strains for astaxanthin production.Different culture media greatly affected the contents and yields of astaxanthin in engineered E.coli.When the expression cassette containing GadE promoter and its driving genes,HpCHY and CrBKT,was inserted into the plasmid pACCAR16DcrtX and expressed in E.coli DH5a,the engineered strain was able to produce 4.30±0.28 mg/g dry cell weight(DCW)or 24.16±2.03 mg/L of astaxanthin,which was a sevenfold or 40-fold increase over the initial production of 0.62±0.03 mg/g DCW or 0.61±0.05 mg/L.展开更多
Of all types of interactions between humans and plants,the utilization of plants by people is the most direct and influential.China has a long history of using native plants and a large body of recorded knowledge on u...Of all types of interactions between humans and plants,the utilization of plants by people is the most direct and influential.China has a long history of using native plants and a large body of recorded knowledge on uses.Here,we present an inventory of plant uses in China based on an extensive survey of the literature.Twelve categories of usage are recognized(medicinal,edible,etc.),these categories being chosen according to an integration of various current standards.A total of 50,521 use-citations were recorded,covering 10,808 species and infraspecies,representing 28%of the Chinese flora.Additional information is included in the dataset on taxonomy and endangerment status.Analysis of the data reveals that the eight plant families with the greatest numbers of species used in China,namely Asteraceae,Fabaceae,Rosaceae,Ranunculaceae,Poaceae,Lamiaceae,Orchidaceae,and Liliaceae,are also the top eight most species-rich Chinese plant families.However,there are some families that are overrepresented or under-representation in certain use categories,compared with their relative abundance in the total flora.There are indications that rare and endangered species are being subject to some degree of over-exploitation.A disproportionately high number of used species are Chinese endemics(3552 species,representing over 33%of used species).A total of 20%of used species have been classified as threatened nationally or globally,according to at least one of the various threat assessments that have been made for the Chinese flora.This comprehensive inventory of the useful plants of China,with relevant ethnobotanical information included,provides a baseline for further studies of plant resources.It will be useful in follow-up research.The scientific dataset it contains will be useful for the protection and sustainable utilization of plant resources in China.展开更多
Establishing a transgenic plant largely relies on a selectable marker gene that can confer antibiotic or herbicide resistance to plant cells.The existence of such selectable marker genes in genetically modified foods ...Establishing a transgenic plant largely relies on a selectable marker gene that can confer antibiotic or herbicide resistance to plant cells.The existence of such selectable marker genes in genetically modified foods has long been criticized.Plant cells generally exhibit too low an activity of phosphomannose isomerase(PMI)to grow with mannose as a sole carbon source.In this study,we characterized PMI from the green microalga Chlorococcum sp.and assessed its feasibility as a selectable marker for plant biotechnology.Chlorococcum sp.PMI(ChlPMI)was shown to be closely related to higher plants but more distant to bacterial counterparts.Overexpression of ChlPMI in tomato induced callus and shoot formation in media containing mannose(6 g/L)and had an average transformation rate of 3.9%.Based on this transformation system,a polycistronic gene cluster containing crtB,HpBHY,CrBKT and SlLCYB(BBBB)was co-expressed in a different tomato cultivar.Six putative transformants were achieved with a transformation rate of 1.4%,which produced significant amounts of astaxanthin due to the expression of the BBBB genes.Taken together,these findings indicate that we have established an additional tool for plant biotechnology that may be suitable for genetically modifying foods safely.展开更多
Two new 2H-pyran-2-one glucosides,cuscutarosides A(1)and B(2),and one new steroidal glucoside,7β-methoxy-β-sitosterol 3-O-β-glucopyranoside(3),together with 12 known compounds(4-15)were isolated from the whole plan...Two new 2H-pyran-2-one glucosides,cuscutarosides A(1)and B(2),and one new steroidal glucoside,7β-methoxy-β-sitosterol 3-O-β-glucopyranoside(3),together with 12 known compounds(4-15)were isolated from the whole plant of Cuscuta reflexa(Convolvulaceae)collected from Myanmar.The chemical structures of these new compounds were elucidated based on extensive spectroscopic analysis.The antiobesity activity of these isolates was evaluated using porcine pancreatic lipase(PPL),and the antiplatelet aggregation activity was screened using rabbit platelets induced by thrombin,platelet-activating factor(PAF),arachidonate(AA),or collagen.7β-Methoxy-β-sitosterol 3-O-β-glucopyranoside(3)showed weak PPL inhibitory activity.Cuscutaroside A(1),its acetylated derivative(1a),and scrophenoside B(8)showed weak inhibitory activity against rabbit platelet aggregation induced by collagen.Compound 1a also showed inhibitory activity against rabbit platelet aggregation induced by AA.展开更多
The transcription factor WRINKLED1(WRI1),a member of AP2 gene family that contain typical AP2 domains,has been considered as a master regulator regulating oil biosynthesis in oilseeds.However,the regulatory mechanism ...The transcription factor WRINKLED1(WRI1),a member of AP2 gene family that contain typical AP2 domains,has been considered as a master regulator regulating oil biosynthesis in oilseeds.However,the regulatory mechanism of RcWRI1 in regulating oil accumulation during seed development has not been clearly addressed.Castor bean(Ricinus communis)is one of the most important non-edible oil crops and its seed oils are rich in hydroxy fatty acids,widely applied in industry.In this study,based on castor bean reference genome,three RcWRIs genes(RcWRI1,RcWRI2 and RcWRI3)were identified and the expressed association of RcWRI1 with oil accumulation were determined.Heterologous transformation of RcWRI1 significantly increased oil content in tobacco leaf,confirming that RcWRI1 activate lipid biosynthesis pathway.Using DNA Affinity Purification sequencing(DAP-seq)technology,we confirmed RcWRI1 binding with Transcription Start Site of genes and identified 7961 WRI1-binding candidate genes.Functionally,these identified genes were mainly involved in diverse metabolism pathways(including lipid biosynthesis).Three cis-elements AW-box([CnTnG](n)7[CG])and AW-boxes like([GnAnC](n)6[GC]/[GnAnC](n)7[G])bound with RcWRI1 were identified.Co-expression network analysis of RcWRI1 further found that RcWRI1 might be widely involved in biosynthesis of storage materials during seed development.In particular,yeast one hybrid experiments found that both AP2 domains within RcWRI1 were required in binding targeted genes.These results not only provide new evidence to understand the regulatory mechanism of RcWRI1 in regulation of oil accumulation during castor bean seed development,but also give candidate gene resource for subsequent genetic improvement toward increasing oil content in oilseed crops.展开更多
Malania oleifera(Olacaceae)is a valued tree species,mostly because its seeds have high precious fatty acid content(particularly nervonic acid).However,seedling mortality rates are often high and regeneration of this t...Malania oleifera(Olacaceae)is a valued tree species,mostly because its seeds have high precious fatty acid content(particularly nervonic acid).However,seedling mortality rates are often high and regeneration of this tree has been problematic,which greatly hinders its utilization at a large scale.Cultivation difficulties of some tree species in the family Olacaceae have been attributed to their root hemiparasitic habit.Prompted by field observations and the taxonomic proximity of M.oleifera to root hemiparasites in Olacaceae,we hypothesized that tuberous structures observed on the roots of M.oleifera are parasitic organs known as haustoria.To test this hypothesis,we collected root samples from M.oleifera plants of various ages and growth conditions,investigated the morphological and anatomical features of tuberous structures and their connections to neighboring roots.Our analyses confirmed that M.oleifera are root hemiparasites.To the best of our knowledge,this is the first empirical report on root hemiparasitism in M.oleifera.Because life strategies of root hemiparasitic plants differ greatly from autotrophic plants,the root hemiparasitic habit needs to be taken into account for successful seedling regeneration of M.oleifera.This study establishes the foundation for investigations into a long-neglected but essential aspect in research of these highly valued tree species.展开更多
Plants have sophisticated defense systems to fend off insect herbivores. How plants defend against herbivores in dicotyledonous plants, such as Arabidopsis and tobacco, have been relatively well studied,yet little is ...Plants have sophisticated defense systems to fend off insect herbivores. How plants defend against herbivores in dicotyledonous plants, such as Arabidopsis and tobacco, have been relatively well studied,yet little is known about the defense responses in monocotyledons. Here, we review the current understanding of rice(Oryza sativa) and maize(Zea mays) defense against insects. In rice and maize,elicitors derived from insect herbivore oral secretions or oviposition fluids activate phytohormone signaling, and transcriptomic changes mediated mainly by transcription factors lead to accumulation of defense-related secondary metabolites. Direct defenses, such as trypsin protein inhibitors in rice and benzoxazinoids in maize, have anti-digestive or toxic effects on insect herbivores. Herbivory-induced plant volatiles, such as terpenes, are indirect defenses, which attract the natural enemies of herbivores. R gene-mediated defenses against herbivores are also discussed.展开更多
Jasmonic acid(JA)plays important roles in plant resistance to insect herbivores.One important derivative of JA is 12-OH-JA,which is produced by two independent pathways:direct hydroxylation of JA by jasmonate-induced ...Jasmonic acid(JA)plays important roles in plant resistance to insect herbivores.One important derivative of JA is 12-OH-JA,which is produced by two independent pathways:direct hydroxylation of JA by jasmonate-induced oxygenases(JOXs)or hydrolyzation of 12-OH-JA-Ile.Yet the function of 12-OH-JA in plant-herbivore interactions remains largely unknown.In this study,we silenced four JOX homologs independently in the wild tobacco Nicotiana attenuata by virus-induced gene silencing(VIGS),and found that all four JOX homologs are involved in JA hydroxylation.Simultaneously silencing the four JA hydroxylases in VIGS-NaJOXs plants decreased herbivory-induced 12-OH-JA by 33%,but JA and JA-Ile levels increased by 45%and 30%,respectively,compared to those in control plants.Compared to direct hydroxylation from JA,hydrolyzation from 12-OH-JA-Ile is equally important for herbivory-induced 12-OHJA accumulation:in the 12-OH-JA-Ile deficient irJAR4/6 plants,12-OH-JA decreased 34%.Moreover,VIGSNaJOXs plants exhibited enhanced resistance to the generalist herbivore Spodoptera litura.The poor larval performance was strongly correlated with high levels of several JA-Ile-dependent direct defense metabolites in the VIGS-NaJOXs plants.When we simultaneously silenced all four JA hydroxylases in the JAIle-deficient irJAR4/6 background,the enhanced herbivore resistance diminished,demonstrating that enhanced herbivore resistance resulted from elevated JA-Ile levels.Given that silencing these NaJOX-like genes did not detectably alter plant growth but highly increased plant defense levels,we propose that JOX genes are potential targets for genetic improvement of herbivore-resistant crops.展开更多
基金supported by the National Natural Science Foundation of China (31970274 (J.W.), 32170272 (X.W.), 32100251 (J.Z.), 32000179 (Y.X.))the Special Research Assistant of Chinese Academy of Sciences (J.Z. and Y.X.), China Postdoctoral Science Foundation (2022M713224 (J.Z.))+6 种基金the Strategic Priority Research Program of Chinese Academy of Sciences (XDPB16 (J.W.))the Yunnan Innovation Team Project (202105AE160013 (J.W.))CAS “Light of West China” Program (G.S.)Yunnan Revitalization Talent Support Program “Young Talents” Project (XDYC-QNRC-2022-0301 (J.Z.), XDYC-QNRC-2022-0001 (G.S.))the General and Key Project of the Applied Basic Research Program of Yunnan (202001AS070021(J.W.))Yunnan Fundamental Research Projects-General Project (202101AT070457 (S.L.))Yunnan Fundamental Research Projects-Youth Talent Project (202101AU070021(S.L.))
文摘Parasitic plants and their hosts communicate through haustorial connections.Nutrient deficiency is a common stress for plants,yet little is known about whether and how host plants and parasites communicate during adaptation to such nutrient stresses.In this study,we used transcriptomics and proteomics to analyze how soybean(Glycine max)and its parasitizing dodder(Cuscuta australis)respond to nitrate and phosphate deficiency(-N and-P).After-N and-P treatment,the soybean and dodder plants exhibited substantial changes of transcriptome and proteome,although soybean plants showed very few transcriptional responses to-P and dodder did not show any transcriptional changes to either-N or-P.Importantly,large-scale interplant transport of mRNAs and proteins was detected.Although the mobile mRNAs only comprised at most 0.2%of the transcriptomes,the foreign mobile proteins could reach 6.8%of the total proteins,suggesting that proteins may be the major forms of interplant communications.Furthermore,the interplant mobility of macromolecules was specifically affected by the nutrient regimes and the transport of these macromolecules was very likely independently regulated.This study provides new insight into the communication between host plants and parasites under stress conditions.
文摘than 80 Dendrobium species have been reported in China.However,there are only six Dendrobium species,namely,D.bigibbum var.superbum(syn.D.phalaenopsis),D.chrysanthum,D.fimbriatum,D.loddigesii,D.nobile,and D.officinale(syn.D.candidum),listed in the New Inventory of Existing Cosmetic Ingredients in China Launched.Artificial planting of Dendrobium species has been a great success in China.To better utilize Dendrobium resources for medicinal and cosmetic purposes,we summarize their traditional uses and pharmacologically active compounds for treating dermatological disorders in this review.“Orchidaceae”,“Dendrobium”,“traditional use”,“ethnobotany”,“dermatological disorder”,and“skin disease”were used as search terms to screen the literature.Cited references were collected between 1970 and 2020 from the Web of Science,China National Knowledge Internet(CNKI),SciFinder,Google Scholar,and Chinese books.From the search,it was found that there are 22 Dendrobium species with traditional uses in dermatological disorders,and 131 compounds from Dendrobium plants have been reported to possess anti-inflammatory,antimicrobial,antioxidant,antiaging,anti-psoriasis,and tyrosinase-inhibitory activities,implying that Dendrobium plants are important resources for the discovery of active compounds and the development of new drugs and cosmetics.D.crepidatum,D.denneanum,D.loddigesii,D.nobile,and D.officinale have been extensively studied.More research on other Dendrobium species is needed.The major active compounds found in Dendrobium species are phenanthrenes,alkaloids,flavonoids,phenylpropanoids,and lignans.Several compounds,such as loddigesiinol A,(S)-5-methoxy-2,4,7,9-tetrahydroxy-9,10-dihydrophenanthrene,(S)-4-methoxy-2,5,7,9-tetrahydroxy-9,10-dihydrophenanthrene,2,5-dihydroxy-4-methoxy-phenanthrene 2-O-β-d-glucopyranoside,(9R)-1,2,5,9-tetrahydroxy-9,10-dihydrophenanthrene 5-O-β-d-glucopyranoside,(+)-homocrepidine A,and vicenin 2,have significant anti-inflammatory activities and inhibit nitric oxide(NO)production with IC_(50) values less than 5μM,and these compounds are worthy of further study.
基金This research was funded by the Biodiversity Investigation,Observation and Assessment Program,Ministry of Ecology and Environment,The People’s Republic of China and the Yunnan Innovative Talents Program,China(No.2018HC009).
文摘In the Qinba mountainous area of Central China,pig farming has a significant impact on the growth of the rural economy and has substantially increased farmer incomes.Traditional knowledge plays an important role in the selection of forage plant species for pig farming by local people.This study aimed to identify the forage plants used for pig feeding and to catalog indigenous knowledge regarding their use.During 2016 and 2017,ethnobotanical surveys and inventories were conducted in Zhuxi County,Hubei Province,China.Data were collected using semi-structured interviews,key informant reports,free listings,guided field walks,and participatory observations with 77 households in 16 villages in 13 towns/townships.The obtained data were analyzed using a relative frequency citation(RFC)index.Overall,145 wild forage plants from 91 genera and 31 families were recorded.The most cited families were Asteraceae,Polygonaceae,Urticaceae,Amaranthaceae,Fabaceae,Cruciferae,Caryophyllaceae,and Lamiaceae.Whole plants(75.9%)and tender leaves(12.4%)were the most frequently used parts of the plants.Most of the forage plants were herbaceous(88.9%).Almost all forage plants could be collected throughout the year(62.7%).Raw and cooked were the two main preparation methods.The most frequently cited species were Taraxacum mongolicum,Bidens pilosa,Sonchus oleraceus,Pilea verrucosa,and Pilea pumila var.obtusifolia.A total of 14 species were identified as the top forage plants in Zhuxi County based on their RFC values(RFC value greater than 0.5).Local people possess rich traditional knowledge about the utilization and management of forage plants for pig feeding.However,the maintenance of this traditional knowledge may be seriously threatened by changes in pig feeding modes and the lack of successors.Appropriate strategies and action plans have been suggested for the conservation of traditional knowledge associated with biodiversity and the sustainable use of forage species resources.These include 1)taking targeted measures to protect forage resources and associated traditional knowledge;2)strengthening research on the forage plants with the highest RFC values for nutritional value,digestibility,other functions,and ecological status;and 3)enhancing the identification of poisonous forage plants.
基金financially supported by the Natural Science Foundation of China(31370512,U1303201,and 31400440)Natural Science Foundation of Yunnan Province(2016FB059)+1 种基金funding for Airong Li from The Youth Innovation Promotion Association of Chinese Academy of Sciencesthe Young Academic and Technical Leader Raising Foundation of Yunnan Province(2014HB047)
文摘Haustorium formation is the characteristic feature of all parasitic plants and a vital process for successful parasitism.Previous investigations on haustorium initiation and development are constricted to induced processes by host-derived signals or synthetic analogs.Spontaneous haustorium formation in the absence of host signals,a process representing an early stage in the evolution of parasitic plants,remains largely unexplored.Lack of fast and frequent formation of spontaneous haustoria greatly hinders full understanding of haustorium formation in root hemiparasites.In this study,seedlings of Pedicularis kansuensis Maxim.,a facultative root hemiparasitic species in Orobanchaceae observed to produce many spontaneous haustoria,were grown in autoclaved water agar in the absence of any known haustoriuminducing stimulants.We aimed to test the temporal and developmental pattern of spontaneous haustorium formation.Also,effects of sucrose supply and root contact on spontaneous haustorium formation were tested.Spontaneous haustoria were observed starting from six days after germination,much earlier than previously reported root hemiparasites.A majority of the spontaneous haustoria formed on lateral roots.Percentage of seedlings with spontaneous haustoria was 28.8% when grown on water agar plates,with a mean of four haustoria per seedling two weeks after germination.Haustorium formation by seedlings grown in water agar amended with 2% sucrose was more than twice of those without sucrose amendment.Singly grown seedlings were able to develop spontaneous haustoria at similar levels as those grown with another conspecific seedling.In view of the fast and abundant formation of spontaneous haustoria,P.kansuensis may be developed as an excellent experimental system in future investigations for unraveling endogenous regulation of haustorium initiation and development in root hemiparasitic plants.
基金supported by the Second Tibetan Plateau Scientific Expedition and Research(STEP)Program(2019QZKK0502)the National Natural Science Foundation of China(NSFC,31400324)+1 种基金Independent research project of Yunnan Provincial Key Laboratory of Wild Resources Plant Research(E03K581261)National Key Research Development Program of China(2022YFC2601200)。
文摘Compared with traditional genetic markers,genomic approaches have proved valuable to the conservation of endangered species.Paeonia ludlowii having rarely and pure yellow flowers,is one of the world’s most famous tree peonies.However,only several wild populations remain in the Yarlung Zangbo Valley(Nyingchi and Shannan regions,Xizang)in China due to increasing anthropogenic impact on the natural habitats.We used genome-wide single nucleotide polymorphisms to elucidate the spatial pattern of genetic variation,population structure and demographic history of P.ludlowii from the fragmented region comprising the entire range of this species,aiming to provide a basis for conserving the genetic resources of this species.Unlike genetic uniformity among populations revealed in previous studies,we found low but varied levels of intra-population genetic diversity,in which lower genetic diversity was detected in the population in Shannan region compared to those in Nyingzhi region.These spatial patterns may be likely associated with different population sizes caused by micro-environment differences in these two regions.Additionally,low genetic differentiation among populations(Fst=0.0037)were detected at the species level.This line of evidence,combined with the result of significant genetic differentiation between the two closest populations and lack of isolation by distance,suggested that shared ancestry among now remnant populations rather than contemporary genetic connectivity resulted in subtle population structure.Demographic inference suggested that P.ludlowii probably experienced a temporal history of sharp population decline during the period of Last Glacial Maximum,and a subsequent bottleneck event resulting from prehistoric human activities on the Qinghai-Tibet Plateau.All these events,together with current habitat fragment and excavation might contribute to the endangered status of P.ludlowii.Our study improved the genetic characterization of the endangered tree peony(P.ludlowii)in China,and these genetic inferences should be considered when making different in situ and ex situ conservation actions for P.ludlowii in this evolutionary hotspot region.
基金supported by the Project for Innovation Team of Yunnan Province (202105AE160012)the Project for Construction of International Flower Technology Innovation Center and Achievement Industrialization (2019ZG006)+2 种基金the Project for the Germplasm Bank of Wild Speciesthe KC Wong Education Foundation,CASthe project for High-level Talent Training Plan of Yunnan Province
文摘Dendrobium nobile is an important medicinal and nutraceutical herb.Although the ingredients of D.nobile have been identified as polysaccharides,alkaloids,amino acids,flavonoids and bibenzyls,our understanding of the metabolic pathways that regulate the synthesis of these compounds is limited.Here,we used transcriptomic and metabolic analyses to elucidate the genes and metabolites involved in the biosynthesis of carbohydrate and several secondary metabolites in the stems of D.nobile.A total of 1005 metabolites and 31,745 genes were detected in the stems of D.nobile.The majority of these metabolites and genes were involved in the metabolism of carbohydrates(fructose,mannose,glucose,xylulose and starch),while some were involved in the metabolism of secondary metabolites(alkaloids,β-tyrosine,ferulic acid,4-hydroxybenzoate and chrysin).Our predicted regulatory network indicated that five genes(AROG,PYK,DXS,ACEE and HMGCR) might play vital roles in the transition from carbohydrate to alkaloid synthesis.Correlation analysis identified that six genes(ALDO,PMM,BGLX,EGLC,XYLB and GLGA) were involved in carbohydrate metabolism,and two genes(ADT and CYP73A) were involved in secondary metabolite biosynthesis.Our analyses also indicated that phosphoenol-pyruvate(PEP) was a crucial bridge that connected carbohydrate to alkaloid biosynthesis.The regulatory network between carbohydrate and secondary metabolite biosynthesis established will provide important insights into the regulation of metabolites and biological systems in Dendrobium species.
基金jointly supported by Chinese National Key Technology R & D Program (2015BAD15B02)National Natural Science Foundation of China (31661143002 and 31501034)
文摘Investigation of the relationships of phenotypic and epigenetic variations might be a good way to dissect the genetic or molecular basis of phenotypic variation and plasticity in plants. Castor bean(Ricinus communis L.), an important non-edible oilseed crop, is a mono-species genus plant in the family Euphorbiaceae. Since it displays rich phenotypic variations with low genetic diversity, castor bean is a good model to investigate the molecular basis of phenotypic and epigenetic variations. Cytosine DNA methylation represents a major molecular mechanism of epigenetic occurrence. In this study, epigenetic diversity of sixty landrace accessions collected worldwide was investigated using the methylationsensitive amplification polymorphism(MSAP) technique. Results showed that the epigenetic diversity(based on the polymorphism of DNA methylated loci) exhibited a medium variation(Ne=1.395,He=0.242,I=0.366) at the population level though the variation was great, ranging from 3.80% to 34.31% among accessions. Both population structure analysis and the phylogenetic construction(using the neighbor-joining criteria) revealed that the two main clades were identified, but they did not display a distinct geographic structure. After inspecting the location of polymorphic methylated loci on genome we identified that the polymorphic methylated loci occur widely in nuclear and organelle genomes. This study provides new data to understand phenotypic and epigenetic variations in castor bean.
基金financially supported by the Natural Science Foundation of China (U1303201, No. 31400440 and No. 31370512)China Agriculture Research System (CARS-34)+2 种基金Natural Science Foundation of Yunnan Province (2016FB059)funding for Airong Li from The Youth Innovation Promotion Association of Chinese Academy of Sciencesthe Young Academic and Technical Leader Raising Foundation of Yunnan Province (2014HB047)
文摘Fertilization has been shown to have suppressive effects on arbuscular mycorrhizal fungi(AMF) and root hemiparasites separately in numerous investigations, but its effects on AMF in the presence of root hemiparasites remain untested. In view of the contrasting nutritional effects of AMF and root hemiparasites on host plants, we tested the hypothesis that fertilization may not show strong suppressive effects on AMF when a plant community was infested by abundant hemiparasitic plants. Plants and soil samples were collected from experimental field plots in Bayanbulak Grassland, where N and P fertilizers had been applied for three continuous years for control against a spreading root hemiparasite, Pedicularis kansuensis. Shoot and root biomass of each plant functional group were determined. Root AMF colonization levels, soil spore abundance, and extraradical hyphae length density were measured for three soil depths(0 e10 cm, 10 e20 cm, 20 e30 cm). Partial 18 S r RNA gene sequencing was used to detect AMF diversity and community composition. In addition, we analyzed the relationship between relative abundance of different AMF genera and environmental factors using Spearman's correlation method. In contrast to suppressive effects reported by many previous studies, fertilization showed no significant effects on AMF root colonization or AMF species diversity in the soil. Instead, a marked increase in soil spore abundance and extraradical hyphae length density were observed. However, fertilization altered relative abundance and AMF composition in the soil. Our results support the hypothesis that fertilization does not significantly influence the abundance and diversity of AMF in a plant community infested by P. kansuensis.
基金National Natural Sci-ence Foundation of China(31670337)Research Project(ZYS2016-001)funded by Yunnan Key Laboratory for Wild Plant Resources.
文摘Zingiber cassumunar is an important plant used in traditional medicine and as a natural mosquito re-pellent.However,the compounds responsible for the repellent activity of the plant are still unknown.The aim of the study is to identify the components of Z.cassumunar essential oil that show repellent activity against Aedes albopictus.We also evaluated the larvicidal and adulticidal activities of Z.cassumunar essential oil against Ae.albopictus.In-cage mosquito repellent experiments showed that Z.cassumunar essential oil possessed moderate repellent activity with a minimum effective dose(MED)of 0.16±0.01 mg/cm^(20,compared to reference standard N,N-diethyl-3-methylbenzamide(DEET,0.03±0.01 mg/cm^(20).Bioassay-guided fractionation identified the major active compound of Z.cassumunar essential oil as(-)-terpinen-4-ol(1)(MED:0.19±0 mg/cm^(20).We also found that Z.cassumunar essential oil showed moderate larvicidal activity against first instar larvae of Ae.albopictus with a LC50(50%lethal concentration)of 44.9 mg/L after 24 h.Fumigation bioassays showed that Z.cassumunar essential oil exhibits moderate adulticidal activity against Ae.albopictus with a LC50 of 5.44%,while(-)-terpinen-4-ol showed significant adulticidal activity with a LC50 of 2.10%after 24 h.This study verifies that the Z.cassumunar essential oil has mosquito repellent activity,and that(-)-terpinen-4-ol is mainly responsible for this activity.Furthermore,this study provides scientific support for the folk usage of Z.cassumunar essential oil as mosquito repellent and indicates that Z.cassumunar essential oil and(-)-terpinen-4-ol can be used as plant-derived repellents and insecticides for mosquito control.
文摘mRNAs are transported within a plant through phloem.Aphids are phloem feeders and dodders(Cuscuta spp.)are parasites which establish phloem connections with host plants.When aphids feed on dodders,whether there is trafficking of mRNAs among aphids,dodders,and host plants and if aphid feeding a匚fects the mRNA transfer between dodders and hosts are unclear.We constructed a green peach aphid(GPA,Myzus persicae)-dodder(Cuscuta austra/is)-cucumber(Cucumis sativus)tritrophic system by infesting GPAs on C.australis,which parasitized cucumber hosts.We found that GPA feeding activated defense-related phytohormonal and transcriptomic responses in both C.australis and cucumbers and large numbers of mRNAs were found to be transferred between C.australis and cucumbers and between C.australis and GPAs;importantly,GPA feeding on C.australis greatly altered inter-species mobile mRNA profiles.Furthermore,three cucumber mRNAs and three GPA mRNAs could be respectively detected in GPAs and cucumbers.Moreover,our statistical analysis indicated that mRNAs with high abundances and long transcript lengths are likely to be mobile.This study reveals the existence of inter-species and even inter-kingdom mRNA movement among insects,parasitic plants,and parasite hosts,and suggests complex regulation of mRNA trafficking.
基金This study was supported by grant from the National Natural Science Foundation of China[31670337]Plant Germplasm Resources Innovation Project of Chinese Academy of Sciences[KFJBRP-007-002].
文摘Hematophagous invertebrates such as mosquitoes,leeches,mites,ticks,lice and bugs cause various problems for humans.Considering reports on insecticide resistance and requirements for improved environmental and toxicological profiles,there is a continuing need to discover and develop new insecticides and repellents.Ethnobotanical surveys of traditional plant-based repellents provide a direct method of identifying plants for potential use.During five field surveys in Bulang,Jinuo and Lahu villages between August 2018 and July 2019,semi-structured interviews were conducted with 237 informants(151 male,86 female;mean age 63).Frequency of citation,use value,informant consensus factor and Jaccard index were employed to statistically analyze the collected data.A total of 709 use reports relating to 32 plant species and 71 remedies were collected.Similarities and differences between the three groups,as well as the Dai and Hani of Xishuangbanna,who were studied earlier,were shown through network analysis.These five ethnic groups living in the same area have a common understanding of traditional botanical knowledge against hematophagous invertebrates,but each group also possesses unique knowledge.Recording and protecting this traditional knowledge is potentially useful for protecting this cultural diversity and related biodiversity and can also have important practical applications.In this study,traditional knowledge provided us with many new potential plants for follow-up research for the development of new insecticides and repellents,among which Artemisia indica,Nicotiana tabacum and Clausena excavata are the most promising.
文摘The evolution of photosynthesis is an important feature of mixotrophic plants.Previous inferences proposed that mixotrophic taxa tend to retain most genes relating to photosynthetic functions but vary in plastid gene content.However,no sequence data are available to test this hypothesis in Ericaceae.To investigate changes in plastid genomes that may result from a transition from autotrophy to mixotrophy,the plastomes of two mixotrophic plants,Pyrola decorata and Chimaphila japonica,were sequenced at Illumina's Genome Analyzer and compared to the published plastome of the autotrophic plant Rhododendron simsii,which also belongs to Ericaceae.The greatest discrepancy between mixotrophic and autotrophic plants was that ndh genes for both P.decorata and C.japonica plastomes have nearly all become pseudogenes.P.decorata and C.japonica also retained all genes directly involved in photosynthesis under strong selection.The calculated rate of nonsynonymous nucleotide substitutions and synonymous substitutions of protein-coding genes(dN/dS) showed that substitution rates in shade plants were apparently higher than those in sunlight plants.The two mixotrophic plastomes were generally very similar to that of non-parasitic plants,although ndh genes were largely pseudogenized.Photosynthesis genes under strong selection were retained in the two mixotrophs,however,with greatly increased substitution rates.Further research is needed to gain a clearer understanding of the evolution of autotrophy and mixotrophy in Ericaceae.
基金This study was supported by a research grant from Department of Economic Plants and Biotechnology,Yunnan Key Laboratory for Wild Plant Resources,Kunming Institute of Botany,Chinese Academy of Sciences.
文摘Astaxanthin is a value-added ketocarotenoid with great potential in nutraceutical and pharmaceutical industries.Genetic engineering of heterologous hosts for astaxanthin production has attracted great attention.In this study,we assessed some key factors,including codon usage of the expressed genes,types of promoters,bacterial strains,and culture media,for engineered Escherichia coli to produce astaxanthin.The effect of codon usage was shown to be related to the types of promoters.E.coli DH5a was superior to other strains for astaxanthin production.Different culture media greatly affected the contents and yields of astaxanthin in engineered E.coli.When the expression cassette containing GadE promoter and its driving genes,HpCHY and CrBKT,was inserted into the plasmid pACCAR16DcrtX and expressed in E.coli DH5a,the engineered strain was able to produce 4.30±0.28 mg/g dry cell weight(DCW)or 24.16±2.03 mg/L of astaxanthin,which was a sevenfold or 40-fold increase over the initial production of 0.62±0.03 mg/g DCW or 0.61±0.05 mg/L.
基金This study was supported by Strategic Priority Research Program of Chinese Academy of Sciences(No.XDA20050204,XDA19050301)National Natural Science Foundation of China(Grant No.32000261)the 13th Five-year Informatization Plan of Chinese Academy of Sciences(No.XXH13506,XXH-13514).
文摘Of all types of interactions between humans and plants,the utilization of plants by people is the most direct and influential.China has a long history of using native plants and a large body of recorded knowledge on uses.Here,we present an inventory of plant uses in China based on an extensive survey of the literature.Twelve categories of usage are recognized(medicinal,edible,etc.),these categories being chosen according to an integration of various current standards.A total of 50,521 use-citations were recorded,covering 10,808 species and infraspecies,representing 28%of the Chinese flora.Additional information is included in the dataset on taxonomy and endangerment status.Analysis of the data reveals that the eight plant families with the greatest numbers of species used in China,namely Asteraceae,Fabaceae,Rosaceae,Ranunculaceae,Poaceae,Lamiaceae,Orchidaceae,and Liliaceae,are also the top eight most species-rich Chinese plant families.However,there are some families that are overrepresented or under-representation in certain use categories,compared with their relative abundance in the total flora.There are indications that rare and endangered species are being subject to some degree of over-exploitation.A disproportionately high number of used species are Chinese endemics(3552 species,representing over 33%of used species).A total of 20%of used species have been classified as threatened nationally or globally,according to at least one of the various threat assessments that have been made for the Chinese flora.This comprehensive inventory of the useful plants of China,with relevant ethnobotanical information included,provides a baseline for further studies of plant resources.It will be useful in follow-up research.The scientific dataset it contains will be useful for the protection and sustainable utilization of plant resources in China.
基金supported by a grant from Yunnan high talents program(Y33D331),Yunnan Province,China.
文摘Establishing a transgenic plant largely relies on a selectable marker gene that can confer antibiotic or herbicide resistance to plant cells.The existence of such selectable marker genes in genetically modified foods has long been criticized.Plant cells generally exhibit too low an activity of phosphomannose isomerase(PMI)to grow with mannose as a sole carbon source.In this study,we characterized PMI from the green microalga Chlorococcum sp.and assessed its feasibility as a selectable marker for plant biotechnology.Chlorococcum sp.PMI(ChlPMI)was shown to be closely related to higher plants but more distant to bacterial counterparts.Overexpression of ChlPMI in tomato induced callus and shoot formation in media containing mannose(6 g/L)and had an average transformation rate of 3.9%.Based on this transformation system,a polycistronic gene cluster containing crtB,HpBHY,CrBKT and SlLCYB(BBBB)was co-expressed in a different tomato cultivar.Six putative transformants were achieved with a transformation rate of 1.4%,which produced significant amounts of astaxanthin due to the expression of the BBBB genes.Taken together,these findings indicate that we have established an additional tool for plant biotechnology that may be suitable for genetically modifying foods safely.
基金supported by the Southeast Asia Biodiversity Research Institute,Chinese Academy of Sciences(Grant Nos.2015CASEABRIRG001 and Y4ZK111B01)the International Partnership Program of Chinese Academy of Sciences(Grant No.153631KYSB20160004)+2 种基金the National Natural Science Foundation of China(31960480)the Joint Special Project of Local Undergraduate Universities in Yunnan Province,China(Grant No.2018FH001-024)the Second Tibetan Plateau Scientific Expedition and Research(STEP)Program of Ministry of Science and Technology of the People’s Republic of China(Grant No.2019QZKK0502).
文摘Two new 2H-pyran-2-one glucosides,cuscutarosides A(1)and B(2),and one new steroidal glucoside,7β-methoxy-β-sitosterol 3-O-β-glucopyranoside(3),together with 12 known compounds(4-15)were isolated from the whole plant of Cuscuta reflexa(Convolvulaceae)collected from Myanmar.The chemical structures of these new compounds were elucidated based on extensive spectroscopic analysis.The antiobesity activity of these isolates was evaluated using porcine pancreatic lipase(PPL),and the antiplatelet aggregation activity was screened using rabbit platelets induced by thrombin,platelet-activating factor(PAF),arachidonate(AA),or collagen.7β-Methoxy-β-sitosterol 3-O-β-glucopyranoside(3)showed weak PPL inhibitory activity.Cuscutaroside A(1),its acetylated derivative(1a),and scrophenoside B(8)showed weak inhibitory activity against rabbit platelet aggregation induced by collagen.Compound 1a also showed inhibitory activity against rabbit platelet aggregation induced by AA.
基金This work was supported by National Natural Science Foundation of China(grant number 31701465)。
文摘The transcription factor WRINKLED1(WRI1),a member of AP2 gene family that contain typical AP2 domains,has been considered as a master regulator regulating oil biosynthesis in oilseeds.However,the regulatory mechanism of RcWRI1 in regulating oil accumulation during seed development has not been clearly addressed.Castor bean(Ricinus communis)is one of the most important non-edible oil crops and its seed oils are rich in hydroxy fatty acids,widely applied in industry.In this study,based on castor bean reference genome,three RcWRIs genes(RcWRI1,RcWRI2 and RcWRI3)were identified and the expressed association of RcWRI1 with oil accumulation were determined.Heterologous transformation of RcWRI1 significantly increased oil content in tobacco leaf,confirming that RcWRI1 activate lipid biosynthesis pathway.Using DNA Affinity Purification sequencing(DAP-seq)technology,we confirmed RcWRI1 binding with Transcription Start Site of genes and identified 7961 WRI1-binding candidate genes.Functionally,these identified genes were mainly involved in diverse metabolism pathways(including lipid biosynthesis).Three cis-elements AW-box([CnTnG](n)7[CG])and AW-boxes like([GnAnC](n)6[GC]/[GnAnC](n)7[G])bound with RcWRI1 were identified.Co-expression network analysis of RcWRI1 further found that RcWRI1 might be widely involved in biosynthesis of storage materials during seed development.In particular,yeast one hybrid experiments found that both AP2 domains within RcWRI1 were required in binding targeted genes.These results not only provide new evidence to understand the regulatory mechanism of RcWRI1 in regulation of oil accumulation during castor bean seed development,but also give candidate gene resource for subsequent genetic improvement toward increasing oil content in oilseed crops.
基金financially supported by funding for Airong Li from Yunnan Ten Thousand Talents Plan Young and Elite Talents Project (YNWR-QNBJ-2018-092)Youth Innovation Promotion Association of Chinese Academy of Sciences (2011276)+2 种基金Young Academic and Technical Leader Raising Foundation of Yunnan Province (2014HB047)funding for Yunju Li from Young Academic and Technical Leader Raising Foundation of Yunnan Province (2019HB060)Yunnan Science and Technology Innovation Team Program (Grant No. 2019HC015)
文摘Malania oleifera(Olacaceae)is a valued tree species,mostly because its seeds have high precious fatty acid content(particularly nervonic acid).However,seedling mortality rates are often high and regeneration of this tree has been problematic,which greatly hinders its utilization at a large scale.Cultivation difficulties of some tree species in the family Olacaceae have been attributed to their root hemiparasitic habit.Prompted by field observations and the taxonomic proximity of M.oleifera to root hemiparasites in Olacaceae,we hypothesized that tuberous structures observed on the roots of M.oleifera are parasitic organs known as haustoria.To test this hypothesis,we collected root samples from M.oleifera plants of various ages and growth conditions,investigated the morphological and anatomical features of tuberous structures and their connections to neighboring roots.Our analyses confirmed that M.oleifera are root hemiparasites.To the best of our knowledge,this is the first empirical report on root hemiparasitism in M.oleifera.Because life strategies of root hemiparasitic plants differ greatly from autotrophic plants,the root hemiparasitic habit needs to be taken into account for successful seedling regeneration of M.oleifera.This study establishes the foundation for investigations into a long-neglected but essential aspect in research of these highly valued tree species.
基金supported by the National Natural Science Foundation of China(Nos.31772179,U1502263,31600213,31470369,and 31770301)
文摘Plants have sophisticated defense systems to fend off insect herbivores. How plants defend against herbivores in dicotyledonous plants, such as Arabidopsis and tobacco, have been relatively well studied,yet little is known about the defense responses in monocotyledons. Here, we review the current understanding of rice(Oryza sativa) and maize(Zea mays) defense against insects. In rice and maize,elicitors derived from insect herbivore oral secretions or oviposition fluids activate phytohormone signaling, and transcriptomic changes mediated mainly by transcription factors lead to accumulation of defense-related secondary metabolites. Direct defenses, such as trypsin protein inhibitors in rice and benzoxazinoids in maize, have anti-digestive or toxic effects on insect herbivores. Herbivory-induced plant volatiles, such as terpenes, are indirect defenses, which attract the natural enemies of herbivores. R gene-mediated defenses against herbivores are also discussed.
基金supported by the Key Project of Applied Basic Research Program of Yunnan(2017FA015)the Young Academic and Technical Leader Raising Foundation of Yunnan Province(no. 2017HB063)+1 种基金the Yunnan Academy of Tobacco Agricultural Sciences(2018530000241002 and 2019530000241003)the Biotechnology Experimental Center at the Kunming Institute of Botany,CAS,for supporting plant cultivation.
文摘Jasmonic acid(JA)plays important roles in plant resistance to insect herbivores.One important derivative of JA is 12-OH-JA,which is produced by two independent pathways:direct hydroxylation of JA by jasmonate-induced oxygenases(JOXs)or hydrolyzation of 12-OH-JA-Ile.Yet the function of 12-OH-JA in plant-herbivore interactions remains largely unknown.In this study,we silenced four JOX homologs independently in the wild tobacco Nicotiana attenuata by virus-induced gene silencing(VIGS),and found that all four JOX homologs are involved in JA hydroxylation.Simultaneously silencing the four JA hydroxylases in VIGS-NaJOXs plants decreased herbivory-induced 12-OH-JA by 33%,but JA and JA-Ile levels increased by 45%and 30%,respectively,compared to those in control plants.Compared to direct hydroxylation from JA,hydrolyzation from 12-OH-JA-Ile is equally important for herbivory-induced 12-OHJA accumulation:in the 12-OH-JA-Ile deficient irJAR4/6 plants,12-OH-JA decreased 34%.Moreover,VIGSNaJOXs plants exhibited enhanced resistance to the generalist herbivore Spodoptera litura.The poor larval performance was strongly correlated with high levels of several JA-Ile-dependent direct defense metabolites in the VIGS-NaJOXs plants.When we simultaneously silenced all four JA hydroxylases in the JAIle-deficient irJAR4/6 background,the enhanced herbivore resistance diminished,demonstrating that enhanced herbivore resistance resulted from elevated JA-Ile levels.Given that silencing these NaJOX-like genes did not detectably alter plant growth but highly increased plant defense levels,we propose that JOX genes are potential targets for genetic improvement of herbivore-resistant crops.
