This study aims to explore the potential of using a blended pulp from Mikania micrantha(M.micrantha)and waste paper for producing composite paper.The effects of the mass ratio of M.micrantha stem to waste paper(MRMW),...This study aims to explore the potential of using a blended pulp from Mikania micrantha(M.micrantha)and waste paper for producing composite paper.The effects of the mass ratio of M.micrantha stem to waste paper(MRMW),the beating time(BT),the water-to-pulp mass ratio(WPMR)and the times of pulp suspension screening(TPSS)on the paper’s basic structural,optical and mechanical properties are investigated.It is found that MRMW primarily affects the grammage(mass per unit area),density,bulkness and whiteness;WPMR mainly affects the thickness and density;TPSS mainly affects the thickness and grammage.When MRMW is 3:7,the composite paper shows higher values for thickness,grammage,density and whiteness;whereas when MRMW is 7:3,these values are lower.Extending BT can increase paper density.The tensile strengths of all prepared samples fall in the range of 1.5 to 4.1 kN/m,indicating their excellent strength properties that meet the demands of many paper applications.The artistic bags and lampshades crafted from this composite paper exhibit a more natural texture compared to conventional packaging paper.This research demonstrates the feasibility of papermaking by using M.micrantha,while showcasing the potential for synergistic integration of waste resources with traditional hand papermaking techniques.展开更多
The stems and leaves of Mikania micrantha were successively extracted with petroleum ether, ethyl acetate and ethanol. In vitro and in vivo test method was adopted to deten＇nine the inhibition activity of three solve...The stems and leaves of Mikania micrantha were successively extracted with petroleum ether, ethyl acetate and ethanol. In vitro and in vivo test method was adopted to deten＇nine the inhibition activity of three solvent extracts against three plant pathogens. Growth rate method showed that ethyl acetate extract could significantly inhibit the mycelial growth of Botrytis circrea, Gtomerclla ciugulata and Fusarium bulbigeuum under the given concentration of 0.09 g/ml in dry sam- ple, and the inhibition rates were all greater than 90%. Organization test showed that the curative effect of petroleum ether extract against B. cirerea was 63.55% under the given concentration of 0.18 g/ml in dry sample, and the curative effect of ethanol extract was 71.47%. In the potting test against Erysiphe gramiuis, the curative effect of petroleum ether extract was 81.26%, while the curative effect of ethyl acetate extract was 62.07%.展开更多
Mikania micrantha Kunth is an invasive alien weed and known as a plant killer around the world.Accurately and rapidly identifying M.micrantha in the wild is important for monitoring its growth status,as this helps man...Mikania micrantha Kunth is an invasive alien weed and known as a plant killer around the world.Accurately and rapidly identifying M.micrantha in the wild is important for monitoring its growth status,as this helps management officials to take the necessary steps to devise a comprehensive strategy to control the invasive weed in the identified area.However,this approach still mainly depends on satellite remote sensing and manual inspection.The cost is high and the accuracy rate and efficiency are low.We acquired color images of the monitoring area in the wild environment using an Unmanned Aerial Vehicle(UAV)and proposed a novel network-MmNet-based on a deep Convolutional Neural Network(CNN)to identify M.micrantha in the images.The network consists of AlexNet Local Response Normalization(LRN),along with the GoogLeNet and continuous convolution of VGG inception models.After training and testing,the identification of 400 testing samples by MmNet is very good,with accuracy of 94.50%and time cost of 10.369 s.Moreover,in quantitative comparative analysis,the proposed MmNet not only has high accuracy and efficiency but also simple construction and outstanding repeatability.Compared with recently popular CNNs,MmNet is more suitable for the identification of M.micrantha in the wild.However,to meet the challenge of wild environments,more M.micrantha images need to be acquired for MmNet training.In addition,the classification labels need to be sorted in more detail.Altogether,this research provides some theoretical and scientific basis for the development of intelligent monitoring and early warning systems for M.micrantha and other invasive species.展开更多
Mikania cordata, an invasive weed is becom- ing a problem in the secondary degraded forests and plantations of Bangladesh, not only competing with but also releasing allelochemicals to cultivated crops. Allelo- pathic...Mikania cordata, an invasive weed is becom- ing a problem in the secondary degraded forests and plantations of Bangladesh, not only competing with but also releasing allelochemicals to cultivated crops. Allelo- pathic effects of the leaves of M. cordata were investigated through an experiment in the green house of the Institute of Forestry and Environmental Sciences, University of Chit- tagong, Bangladesh. Five economically important agricul- tural crops （Oryza sativa L., Triticum aestivum L., Vigna sinensis L., Abelmoschus esculentus L. and Amaranthus tricolor L.） and three forest crops （Acacia auriculiformis A. Cunn. ex Benth. ＆ Hook, Albizia procera （Roxb.） Benth., and Paraserianthes falcataria （L.） Nielson） were used as bioassay species. Experiments were conducted on trays at an average room temperature 27 ~C. The effects of dif- ferent concentrations of leaf extracts were compared to controls. Water soluble allelochemicals of M. cordata inhibited the germination and initial growth of the tested agricultural and forest crops. Germination percent of forest crops declined with increasing concentration of extracts. The inhibitory effect on root elongation of forest crops was pronounced, whereas a stimulatory effect was found on P. falcataria up to a concentration of 25 %. Abelmoschus esculentus showed poor germination （%） and low shoot development （0.5 cm） and no development of taproot or lateral roots at treatment of 100 % concentration. Theinhibitory effect was proportional to the concentrations of the extracts with higher concentrations producing stronger inhibitory effects. Lower concentrations showed some stimulatory effect. The inhibitory effect was pronounced in root and lateral root development rather than germination or shoot development of the crops. Mikania cordata should be eradicated for healthy growth and development of the forest and adjacent agricultural crops.展开更多
Mikania micrantha is a fast-growing global invasive weed species that causes severe damage to natural ecosystems and very large economic losses of forest and crop production.It has advantages in photosynthesis,includi...Mikania micrantha is a fast-growing global invasive weed species that causes severe damage to natural ecosystems and very large economic losses of forest and crop production.It has advantages in photosynthesis,including a similar net photosynthetic rate as C4 plants and a higher carbon fixation capacity.We used a combination of genomics and transcriptomics approaches to study the evolutionary mechanisms and circadian expression patterns of M.micrantha.In M.micrantha,16 positive selection genes focused on photoreaction and utilization of photoassimilates.In different tissues,98.1%of the genes associated with photoresponse had high expression in stems,and more than half of the genes of the C4 cycle had higher expression in stems than in leaves.In stomatal opening and closing,2 genes of carbonic anhydrase(CAs)had higher expression at 18:00 than at 8:00,and the slow anion channel 1(SLAC1)and high-leaf-temperature 1 kinase(HT1)genes were expressed at low levels at 18:00.In addition,genes associated with photosynthesis had higher expression levels at 7:00 and 17:00.We hypothesized that M.micrantha may undergo photosynthesis in the stem and flower organs and that some stomata of the leaves were opening at night by CO_(2)signals.In addition,its evolution may attenuate photoinhibition at high light intensities,and enhance more efficient of photosynthesis during low light intensity.And the tissue-specific photosynthetic types and different diurnal pattern of photosynthetic-related genes may contribute to its rapid colonization of new habitats of M.micrantha.展开更多
[ Objective ] The paper was to understand distribution and damage of alien weed Mikania micramhaln in Huiyang District of China. [ Method ] The coverage, nearby water sources, surrounding plants and control status of ...[ Objective ] The paper was to understand distribution and damage of alien weed Mikania micramhaln in Huiyang District of China. [ Method ] The coverage, nearby water sources, surrounding plants and control status of M. micranthain under different habitats in Huiyang District were surveyed. [ Result] M. micrantha grew violently in the habitats of irrigation ditches, orchard, field edge and wasteland with the coverage ranging from 10% to 90%. It grew more seriously around water sources and was very likely to recur after control. The wild growth of M. micranthaln was harmful to local agriculture, forestry and fishery. The com- prehensive control measures combing artificial control, chemical control, biological control and ecological control should be adopted in different habitats. [ Conclusion] The study orovided basis for comorehensive control and invasion risk assessment of M. micranthain.展开更多
OBJECTIVE To isolate and characterize bioactive compound from traditionally important medicinal plant Mikania cordata,and to investigate muti-faced pharmacological activities of the isolated compound.METHODS A triterp...OBJECTIVE To isolate and characterize bioactive compound from traditionally important medicinal plant Mikania cordata,and to investigate muti-faced pharmacological activities of the isolated compound.METHODS A triterpeenoid,16-hydroxy betulinic acid(16 HBA) was isolated from Mikania cordata leaf and the structure of the compound was determined by NMR spectroscopic means.Antimicrobial activity of 16 HBA was tested by disc diffusion method and minimum inhibitory concentration(MIC) against the tested microorganisms was determined.The analgesic property of 16 HBA was tested using acetic acid-induced writhes in mice and hot plate thermal stimulation in rats.The anti-inflammatory activity was studied using carrageenin-induced paw edema method.The antipyretic potential of 16 HBA was evaluated by using yeast-induced hyperthermia in rats.RESULTS The triterpenoid 16 HBA showed potent antibacterial activity with inhibition zone of diameter ranging from 12.0~17.5 mm and antifungal activity with mycelial growth inhibition ranges from 37.6%~54.5%.The MIC values for antibacterial and antifungal activities ranged from 31.5~125 and 250~1000 μg·mL-1 respectively.The compound(50 and100 mg·kg^(-1) body weight) showed potent peripheral and central analgesic activity having 55.19% and41% of writhing inhibition at 90 min after administration of the compound and the highest 55.98%,79.18% elongation of reaction time,respectively.In anti-inflammatory activity screening,the compound(100 mg·kg^(-1)) revealed the highest 77.08% edema inhibition at 4 h after administration of carrageenan.In antipyretic assay,16 HBA exhibited a strong antipyretic effect in yeast-induced rats.CONCLUSION The present study confirmed that 16-hydroxy betulinic acid isolated from Mikania cordata has potent antimicrobial,analgesic,anti-inflammatory and antipyretic properties.Our results can be seen as scientific support for the traditional and folklore usage of Mikania cordata in Bangladesh for the treatment of different ailments and provide opportunities to explore this plant as a source bioactive compounds for biochemical and pharmaceutical industries.展开更多
[Objective] The paper was to explore the herbicidal effects of Periconia heveae culture filtrate on Mikania micrantha. [Method] Through indoor bioassay method, the inhibition effects of culture filtrates of seven spec...[Objective] The paper was to explore the herbicidal effects of Periconia heveae culture filtrate on Mikania micrantha. [Method] Through indoor bioassay method, the inhibition effects of culture filtrates of seven species of plant disease fungi on seed germination and seedling growth of M. micrantha were studied, and the security of P. heveae culture filtrate on pepper （Capsicum annuum） and tomato （Solanum lycopersicum） was also evaluated. [Result] The culture filtrates of P. heveae had strong inhibition effects on seed germination and the growth of root, shoot and seedling of M. micrantha, and the inhibition rates were 72.7%, 93.0%, 32.4%, and 54.6% （fresh weight）, respectively. Security tests showed that culture filtrates of P. heveae were safe to seed germination and root and shoot growth of tomato, and the growth rate had no significant difference with control, but they inhibited seed germination of pepper. [Conclusion] As potential biological herbicide, the culture filtrate and metabolites of P. heveae is worthy of further development. .展开更多
[Objectives]The paper was to understand the occurrence and damage regularity of the invasive plant Mikania micrantha in Huadu District of Guangzhou.[Methods]The damage status of M.micranthFa in different forest lands ...[Objectives]The paper was to understand the occurrence and damage regularity of the invasive plant Mikania micrantha in Huadu District of Guangzhou.[Methods]The damage status of M.micranthFa in different forest lands and its annual growth dynamics were investigated by field investigation.[Results]With the change of canopy density from low to high,the occurrence degree of M.micrantha changed from high to low.The occurrence degree of M.micrantha in different forest land types was:abandoned orchard>wasteland>roadside greenbelt>waterside>forest edge>normally managed orchard.[Conclusions]M.micrantha enters the rapid growth period from March to May in spring,with the growth rate gradually slowing down after June.The result provides a theoretical basis and practical guidance for the prevention and control of M.micrantha.展开更多
Biochar can potentially reduce heavy metals(HMs)mobility and bioavailability during composting.However,siderophores secreted by functional microbes might lead to the re-mobilization of metals like Cu and Zn.Therefore,...Biochar can potentially reduce heavy metals(HMs)mobility and bioavailability during composting.However,siderophores secreted by functional microbes might lead to the re-mobilization of metals like Cu and Zn.Therefore,this study intended to explore the impacts of Mikania micrantha Kunth(MM)and MM-derived biochar(MMB)in the reduction of Cu and Zn bioavailability,and siderophore-related gene abundances during composting.Compared with MM and corn straw(CS)composts,a significant decline was noticed in the extractable and reducible Cu[(2.3 mg kg^(−1)+12.1 mg kg^(−1)),and(3.3 mg kg^(−1)+14.6 mg kg^(−1))],and Zn[(103.1 mg kg^(−1)+110.1 mg kg^(−1)),and(109.6 mg kg^(−1)+117.2 mg kg^(−1))]in MMB and corn straw biochar(CSB)composts,respectively.Besides,the lowest relative abundance of HMs-resistant bacteria particularly Corynebacterium(0.40%),Pseudomonas(0.46%),and Enterobacter(0.47%),was noted in MMB compost.Also,a significant increase in sesquiterpenoid and triterpenoid biosynthesis abundance(5.77%)accompanied by a reduction in the abundance of clusters related to siderophore transport,and siderophore transmembrane transporter activity was detected in MMB compost.Multivariate analysis labeled temperature,moisture content,total organic carbon,Corynebacterium,and Bacillus as the primary factors significantly correlated with the Cu and Zn bioavailability(−0.90≤r≤0.90,P<0.05).The structural equation model revealed that physicochemical parameters,microbial abundance,and siderophores exert a substantial influence on Cu and Zn bioavailability.Accordingly,MM and its derived biochar are recommended as an effective approach for accelerating Cu and Zn bioavailability reduction and managing the growth and distribution of invasive plants.展开更多
The invasive plant Mikania micrantha Kunth(M.micrantha)from South America poses a significant threat to the stability and biodiversity of ecosystems.However,an effective and economical method to control M.micrantha is...The invasive plant Mikania micrantha Kunth(M.micrantha)from South America poses a significant threat to the stability and biodiversity of ecosystems.However,an effective and economical method to control M.micrantha is still lacking.RNA interference(RNAi)has been widely studied and applied in agriculture for trait improvement.Spray-induced gene silencing(SIGS)can produce RNAi silencing effects without introducing heritable modifications to the plant genome and is becoming a novel nontransformation strategy for plant protection.In this study,the genes encoding chlorophyll a/b-binding proteins were selected as targets of RNAi,based on high-throughput sequencing of M.micrantha transcriptome and bioinformatic analyses of sequence specificity.Three types of RNAi molecules,double-stranded RNA,RNAi nanomicrosphere,and short hairpin RNA(shRNA),with their corresponding short interfering RNA sequences were designed and synthesized for SIGS vector construction,from which each RNAi molecule was transcribed and extracted to be sprayed on M.micrantha leaves.Whereas water-treated control leaves remained green,leaves treated with RNAi molecules turned yellow and eventually wilted.Quantitative real-time PCR showed that the expression levels of target genes were significantly reduced in the RNAi-treated groups compared with those of the control,suggesting that all three types of RNAi herbicides effectively silenced the endogenous target genes,which are essential for the growth of M.micrantha.We also found that shRNA showed better silencing efficiency than the other two molecules.Taken together,our study successfully designed three types of RNAi-based herbicides that specifically silenced endogenous target genes and controlled the growth of M.micrantha.Moreover,we identified a gene family encoding chlorophyll a/b-binding proteins that is important for the growth and development of M.micrantha and could serve as potential targets for controlling the spread of M.micrantha.展开更多
Mikania micrantha(Asteraceae)is an invasive vine found in tropical and southern subtropical Asian and the Pacifc Islands.The current methods used to control this vine are inadequate,which warrants the development of e...Mikania micrantha(Asteraceae)is an invasive vine found in tropical and southern subtropical Asian and the Pacifc Islands.The current methods used to control this vine are inadequate,which warrants the development of ecologically sustainable methods.Therefore,we investigated the ability of four grass species to prevent the invasion of M.micrantha,with an ultimate goal of developing ecologically sustainable control methods for widespread application.The clumps of native grass species from China(Panicum incomtum,Pennisetum purpureum,Saccharum arundinaceum and Microstegium vagans)were established.We sowed M.micrantha seeds and transplanted the seedlings into the grass clumps to examine whether the clumps could eliminate the new M.micrantha plants.In addition,we transplanted M.micrantha into existing grass clumps to examine whether the grass clumps could prevent the re-invasion of M.micrantha.Furthermore,we grew M.micrantha with P.incomtum and P.purpureum in the feld to examine whether the grasses could outcompete M.micrantha.Mikania micrantha seeds germinated hardly in the grass clumps,and all seedlings died within 3 months.It was diffcult for the vine to survive in the grass clumps.Our feld experiments showed that the coverage of M.micrantha was signifcantly lower than that of the grass species in the frst year,and that the vine was outcompeted after 2 years.To the best of our knowledge,this study is the frst to reveal that tall grasses,particularly P.incomtum and P.purpureum,have potential to serve as bio-control agents for M.micrantha.展开更多
文摘This study aims to explore the potential of using a blended pulp from Mikania micrantha(M.micrantha)and waste paper for producing composite paper.The effects of the mass ratio of M.micrantha stem to waste paper(MRMW),the beating time(BT),the water-to-pulp mass ratio(WPMR)and the times of pulp suspension screening(TPSS)on the paper’s basic structural,optical and mechanical properties are investigated.It is found that MRMW primarily affects the grammage(mass per unit area),density,bulkness and whiteness;WPMR mainly affects the thickness and density;TPSS mainly affects the thickness and grammage.When MRMW is 3:7,the composite paper shows higher values for thickness,grammage,density and whiteness;whereas when MRMW is 7:3,these values are lower.Extending BT can increase paper density.The tensile strengths of all prepared samples fall in the range of 1.5 to 4.1 kN/m,indicating their excellent strength properties that meet the demands of many paper applications.The artistic bags and lampshades crafted from this composite paper exhibit a more natural texture compared to conventional packaging paper.This research demonstrates the feasibility of papermaking by using M.micrantha,while showcasing the potential for synergistic integration of waste resources with traditional hand papermaking techniques.
基金Supported by Special Research for National Public Service Sectors (Agriculture) (200903052)~~
文摘The stems and leaves of Mikania micrantha were successively extracted with petroleum ether, ethyl acetate and ethanol. In vitro and in vivo test method was adopted to deten＇nine the inhibition activity of three solvent extracts against three plant pathogens. Growth rate method showed that ethyl acetate extract could significantly inhibit the mycelial growth of Botrytis circrea, Gtomerclla ciugulata and Fusarium bulbigeuum under the given concentration of 0.09 g/ml in dry sam- ple, and the inhibition rates were all greater than 90%. Organization test showed that the curative effect of petroleum ether extract against B. cirerea was 63.55% under the given concentration of 0.18 g/ml in dry sample, and the curative effect of ethanol extract was 71.47%. In the potting test against Erysiphe gramiuis, the curative effect of petroleum ether extract was 81.26%, while the curative effect of ethyl acetate extract was 62.07%.
基金supported by the National Natural Science Foundation of China(3180111238)the Fund Project of the Key Laboratory of Integrated Pest Management on Crops in South China,Ministry of Agriculture and Rural Affairs,China(SCIPM2018-05)+2 种基金the Key Research and Development Program of Nanning,China(20192065)the Guangdong Science and Technology Planning Project,China(2017A020216022)the Industrial Development Fund Support Project of Dapeng District,Shenzhen,China(KY20180117)。
文摘Mikania micrantha Kunth is an invasive alien weed and known as a plant killer around the world.Accurately and rapidly identifying M.micrantha in the wild is important for monitoring its growth status,as this helps management officials to take the necessary steps to devise a comprehensive strategy to control the invasive weed in the identified area.However,this approach still mainly depends on satellite remote sensing and manual inspection.The cost is high and the accuracy rate and efficiency are low.We acquired color images of the monitoring area in the wild environment using an Unmanned Aerial Vehicle(UAV)and proposed a novel network-MmNet-based on a deep Convolutional Neural Network(CNN)to identify M.micrantha in the images.The network consists of AlexNet Local Response Normalization(LRN),along with the GoogLeNet and continuous convolution of VGG inception models.After training and testing,the identification of 400 testing samples by MmNet is very good,with accuracy of 94.50%and time cost of 10.369 s.Moreover,in quantitative comparative analysis,the proposed MmNet not only has high accuracy and efficiency but also simple construction and outstanding repeatability.Compared with recently popular CNNs,MmNet is more suitable for the identification of M.micrantha in the wild.However,to meet the challenge of wild environments,more M.micrantha images need to be acquired for MmNet training.In addition,the classification labels need to be sorted in more detail.Altogether,this research provides some theoretical and scientific basis for the development of intelligent monitoring and early warning systems for M.micrantha and other invasive species.
文摘Mikania cordata, an invasive weed is becom- ing a problem in the secondary degraded forests and plantations of Bangladesh, not only competing with but also releasing allelochemicals to cultivated crops. Allelo- pathic effects of the leaves of M. cordata were investigated through an experiment in the green house of the Institute of Forestry and Environmental Sciences, University of Chit- tagong, Bangladesh. Five economically important agricul- tural crops （Oryza sativa L., Triticum aestivum L., Vigna sinensis L., Abelmoschus esculentus L. and Amaranthus tricolor L.） and three forest crops （Acacia auriculiformis A. Cunn. ex Benth. ＆ Hook, Albizia procera （Roxb.） Benth., and Paraserianthes falcataria （L.） Nielson） were used as bioassay species. Experiments were conducted on trays at an average room temperature 27 ~C. The effects of dif- ferent concentrations of leaf extracts were compared to controls. Water soluble allelochemicals of M. cordata inhibited the germination and initial growth of the tested agricultural and forest crops. Germination percent of forest crops declined with increasing concentration of extracts. The inhibitory effect on root elongation of forest crops was pronounced, whereas a stimulatory effect was found on P. falcataria up to a concentration of 25 %. Abelmoschus esculentus showed poor germination （%） and low shoot development （0.5 cm） and no development of taproot or lateral roots at treatment of 100 % concentration. Theinhibitory effect was proportional to the concentrations of the extracts with higher concentrations producing stronger inhibitory effects. Lower concentrations showed some stimulatory effect. The inhibitory effect was pronounced in root and lateral root development rather than germination or shoot development of the crops. Mikania cordata should be eradicated for healthy growth and development of the forest and adjacent agricultural crops.
基金funded by the National Natural Science Foundation of China(32072490)the National Key R&D Program of China(2021YFC2600100 and2021YFC2600101)the Agricultural Science and Technology Innovation Program,China。
文摘Mikania micrantha is a fast-growing global invasive weed species that causes severe damage to natural ecosystems and very large economic losses of forest and crop production.It has advantages in photosynthesis,including a similar net photosynthetic rate as C4 plants and a higher carbon fixation capacity.We used a combination of genomics and transcriptomics approaches to study the evolutionary mechanisms and circadian expression patterns of M.micrantha.In M.micrantha,16 positive selection genes focused on photoreaction and utilization of photoassimilates.In different tissues,98.1%of the genes associated with photoresponse had high expression in stems,and more than half of the genes of the C4 cycle had higher expression in stems than in leaves.In stomatal opening and closing,2 genes of carbonic anhydrase(CAs)had higher expression at 18:00 than at 8:00,and the slow anion channel 1(SLAC1)and high-leaf-temperature 1 kinase(HT1)genes were expressed at low levels at 18:00.In addition,genes associated with photosynthesis had higher expression levels at 7:00 and 17:00.We hypothesized that M.micrantha may undergo photosynthesis in the stem and flower organs and that some stomata of the leaves were opening at night by CO_(2)signals.In addition,its evolution may attenuate photoinhibition at high light intensities,and enhance more efficient of photosynthesis during low light intensity.And the tissue-specific photosynthetic types and different diurnal pattern of photosynthetic-related genes may contribute to its rapid colonization of new habitats of M.micrantha.
基金Supported by Special Fund for Scientific Research in the Public Interest(201103027)Eleventh Five-Year National Science and Technology Support Project(2006BAD32B0103)
文摘[ Objective ] The paper was to understand distribution and damage of alien weed Mikania micramhaln in Huiyang District of China. [ Method ] The coverage, nearby water sources, surrounding plants and control status of M. micranthain under different habitats in Huiyang District were surveyed. [ Result] M. micrantha grew violently in the habitats of irrigation ditches, orchard, field edge and wasteland with the coverage ranging from 10% to 90%. It grew more seriously around water sources and was very likely to recur after control. The wild growth of M. micranthaln was harmful to local agriculture, forestry and fishery. The com- prehensive control measures combing artificial control, chemical control, biological control and ecological control should be adopted in different habitats. [ Conclusion] The study orovided basis for comorehensive control and invasion risk assessment of M. micranthain.
基金supported by Centre for Biomedical Research,University of Dhaka and Department of Applied Chemistry&Chemical Technology,Islamic University,Kushtia,Bangladesh
文摘OBJECTIVE To isolate and characterize bioactive compound from traditionally important medicinal plant Mikania cordata,and to investigate muti-faced pharmacological activities of the isolated compound.METHODS A triterpeenoid,16-hydroxy betulinic acid(16 HBA) was isolated from Mikania cordata leaf and the structure of the compound was determined by NMR spectroscopic means.Antimicrobial activity of 16 HBA was tested by disc diffusion method and minimum inhibitory concentration(MIC) against the tested microorganisms was determined.The analgesic property of 16 HBA was tested using acetic acid-induced writhes in mice and hot plate thermal stimulation in rats.The anti-inflammatory activity was studied using carrageenin-induced paw edema method.The antipyretic potential of 16 HBA was evaluated by using yeast-induced hyperthermia in rats.RESULTS The triterpenoid 16 HBA showed potent antibacterial activity with inhibition zone of diameter ranging from 12.0~17.5 mm and antifungal activity with mycelial growth inhibition ranges from 37.6%~54.5%.The MIC values for antibacterial and antifungal activities ranged from 31.5~125 and 250~1000 μg·mL-1 respectively.The compound(50 and100 mg·kg^(-1) body weight) showed potent peripheral and central analgesic activity having 55.19% and41% of writhing inhibition at 90 min after administration of the compound and the highest 55.98%,79.18% elongation of reaction time,respectively.In anti-inflammatory activity screening,the compound(100 mg·kg^(-1)) revealed the highest 77.08% edema inhibition at 4 h after administration of carrageenan.In antipyretic assay,16 HBA exhibited a strong antipyretic effect in yeast-induced rats.CONCLUSION The present study confirmed that 16-hydroxy betulinic acid isolated from Mikania cordata has potent antimicrobial,analgesic,anti-inflammatory and antipyretic properties.Our results can be seen as scientific support for the traditional and folklore usage of Mikania cordata in Bangladesh for the treatment of different ailments and provide opportunities to explore this plant as a source bioactive compounds for biochemical and pharmaceutical industries.
基金Supported by Research Special Project of Public Industry(Agriculture)(201103027)Control of Invasive Alien Species of MOA & International Cooperation Project of MOST(2011DFB30040)+1 种基金Key Project of Science andTechnology of Hainan Province(080149)Basic Scientific Research Expenses for Central Scientific Research Institutes in Environment and Plant Protection Institute,Chinese Academy of Tropical Agricultural Sciences(2009hzs1J018)
文摘[Objective] The paper was to explore the herbicidal effects of Periconia heveae culture filtrate on Mikania micrantha. [Method] Through indoor bioassay method, the inhibition effects of culture filtrates of seven species of plant disease fungi on seed germination and seedling growth of M. micrantha were studied, and the security of P. heveae culture filtrate on pepper （Capsicum annuum） and tomato （Solanum lycopersicum） was also evaluated. [Result] The culture filtrates of P. heveae had strong inhibition effects on seed germination and the growth of root, shoot and seedling of M. micrantha, and the inhibition rates were 72.7%, 93.0%, 32.4%, and 54.6% （fresh weight）, respectively. Security tests showed that culture filtrates of P. heveae were safe to seed germination and root and shoot growth of tomato, and the growth rate had no significant difference with control, but they inhibited seed germination of pepper. [Conclusion] As potential biological herbicide, the culture filtrate and metabolites of P. heveae is worthy of further development. .
文摘[Objectives]The paper was to understand the occurrence and damage regularity of the invasive plant Mikania micrantha in Huadu District of Guangzhou.[Methods]The damage status of M.micranthFa in different forest lands and its annual growth dynamics were investigated by field investigation.[Results]With the change of canopy density from low to high,the occurrence degree of M.micrantha changed from high to low.The occurrence degree of M.micrantha in different forest land types was:abandoned orchard>wasteland>roadside greenbelt>waterside>forest edge>normally managed orchard.[Conclusions]M.micrantha enters the rapid growth period from March to May in spring,with the growth rate gradually slowing down after June.The result provides a theoretical basis and practical guidance for the prevention and control of M.micrantha.
基金funded by the National Natural Science Foundation of China(Grant number 31971554)Guangdong Basic and Applied Basic Research Foundation,China(Grant number 2023A1515011565)Project for Key Technologies R&D Innovation Team in Modern Agriculture,Guangdong(2022KJ134,2023KJ134).
文摘Biochar can potentially reduce heavy metals(HMs)mobility and bioavailability during composting.However,siderophores secreted by functional microbes might lead to the re-mobilization of metals like Cu and Zn.Therefore,this study intended to explore the impacts of Mikania micrantha Kunth(MM)and MM-derived biochar(MMB)in the reduction of Cu and Zn bioavailability,and siderophore-related gene abundances during composting.Compared with MM and corn straw(CS)composts,a significant decline was noticed in the extractable and reducible Cu[(2.3 mg kg^(−1)+12.1 mg kg^(−1)),and(3.3 mg kg^(−1)+14.6 mg kg^(−1))],and Zn[(103.1 mg kg^(−1)+110.1 mg kg^(−1)),and(109.6 mg kg^(−1)+117.2 mg kg^(−1))]in MMB and corn straw biochar(CSB)composts,respectively.Besides,the lowest relative abundance of HMs-resistant bacteria particularly Corynebacterium(0.40%),Pseudomonas(0.46%),and Enterobacter(0.47%),was noted in MMB compost.Also,a significant increase in sesquiterpenoid and triterpenoid biosynthesis abundance(5.77%)accompanied by a reduction in the abundance of clusters related to siderophore transport,and siderophore transmembrane transporter activity was detected in MMB compost.Multivariate analysis labeled temperature,moisture content,total organic carbon,Corynebacterium,and Bacillus as the primary factors significantly correlated with the Cu and Zn bioavailability(−0.90≤r≤0.90,P<0.05).The structural equation model revealed that physicochemical parameters,microbial abundance,and siderophores exert a substantial influence on Cu and Zn bioavailability.Accordingly,MM and its derived biochar are recommended as an effective approach for accelerating Cu and Zn bioavailability reduction and managing the growth and distribution of invasive plants.
基金This research was financially supported by grants from the Shenzhen Science and Technology Program,China(Grant No.JCYJ20190808115005598)National Natural Science Foundation of China(Grant No.31801078)+1 种基金Guangdong Innovation Research Team Fun(Grant No.2014ZT05S078),Natural Science Foundation of SZU(Grant.No.2019080)the Undergraduate Academic Competition Project of Shenzhen University(Grant No.803-0000290846).
文摘The invasive plant Mikania micrantha Kunth(M.micrantha)from South America poses a significant threat to the stability and biodiversity of ecosystems.However,an effective and economical method to control M.micrantha is still lacking.RNA interference(RNAi)has been widely studied and applied in agriculture for trait improvement.Spray-induced gene silencing(SIGS)can produce RNAi silencing effects without introducing heritable modifications to the plant genome and is becoming a novel nontransformation strategy for plant protection.In this study,the genes encoding chlorophyll a/b-binding proteins were selected as targets of RNAi,based on high-throughput sequencing of M.micrantha transcriptome and bioinformatic analyses of sequence specificity.Three types of RNAi molecules,double-stranded RNA,RNAi nanomicrosphere,and short hairpin RNA(shRNA),with their corresponding short interfering RNA sequences were designed and synthesized for SIGS vector construction,from which each RNAi molecule was transcribed and extracted to be sprayed on M.micrantha leaves.Whereas water-treated control leaves remained green,leaves treated with RNAi molecules turned yellow and eventually wilted.Quantitative real-time PCR showed that the expression levels of target genes were significantly reduced in the RNAi-treated groups compared with those of the control,suggesting that all three types of RNAi herbicides effectively silenced the endogenous target genes,which are essential for the growth of M.micrantha.We also found that shRNA showed better silencing efficiency than the other two molecules.Taken together,our study successfully designed three types of RNAi-based herbicides that specifically silenced endogenous target genes and controlled the growth of M.micrantha.Moreover,we identified a gene family encoding chlorophyll a/b-binding proteins that is important for the growth and development of M.micrantha and could serve as potential targets for controlling the spread of M.micrantha.
基金funded by the National Natural Science Foundation of China(Project 30570330 and 30370243)Hongda Zhang Scientifc Research Fund,Sun Yat-Sen University,and Shenzhen Greening Committee:Non-Environmental Disruptive Control of Mikania micrantha(2010-13)Ecological Forestry Special Fund,Forestry Administration of Guangdong Province(KH2101501).
文摘Mikania micrantha(Asteraceae)is an invasive vine found in tropical and southern subtropical Asian and the Pacifc Islands.The current methods used to control this vine are inadequate,which warrants the development of ecologically sustainable methods.Therefore,we investigated the ability of four grass species to prevent the invasion of M.micrantha,with an ultimate goal of developing ecologically sustainable control methods for widespread application.The clumps of native grass species from China(Panicum incomtum,Pennisetum purpureum,Saccharum arundinaceum and Microstegium vagans)were established.We sowed M.micrantha seeds and transplanted the seedlings into the grass clumps to examine whether the clumps could eliminate the new M.micrantha plants.In addition,we transplanted M.micrantha into existing grass clumps to examine whether the grass clumps could prevent the re-invasion of M.micrantha.Furthermore,we grew M.micrantha with P.incomtum and P.purpureum in the feld to examine whether the grasses could outcompete M.micrantha.Mikania micrantha seeds germinated hardly in the grass clumps,and all seedlings died within 3 months.It was diffcult for the vine to survive in the grass clumps.Our feld experiments showed that the coverage of M.micrantha was signifcantly lower than that of the grass species in the frst year,and that the vine was outcompeted after 2 years.To the best of our knowledge,this study is the frst to reveal that tall grasses,particularly P.incomtum and P.purpureum,have potential to serve as bio-control agents for M.micrantha.
