Rice,the main food crop in China,has been sporadically reported to suffer from weedy rice infestation.However,the overall occurrence and distribution pattern of Chinese weedy rice remains unclear because a systematic ...Rice,the main food crop in China,has been sporadically reported to suffer from weedy rice infestation.However,the overall occurrence and distribution pattern of Chinese weedy rice remains unclear because a systematic survey has not been conducted.In order to reveal the infestation of Chinese weedy rice,a field survey was conducted in 999 sampling sites all over the rice-growing regions in China from 2009 to 2016 using seven-scale visual scoring of the level of weed infestation.Weedy rice was found 39%occurrence incidence in a total of 387 sites.The sampling sites with 50%or higher overall weedy rice infestation index mainly radiated from Jiangsu,Heilongjiang,Ningxia and Guangdong to the whole East China,Northeast China,Northwest China and South China.A total of 45 morphological characters from 287 populations(collected simultaneously with the field survey)out of those occurred sites were observed and analyzed using multivariate analysis in common gardens with the same cultivation conditions in 2017 and 2019.Canonical correlation analysis showed that 45 morphological characters were significantly related to the latitude,mean temperature,minimum temperature,precipitation and mean diurnal range factors.The 287 weedy rice populations were divided into three morphological groups with climate-dependent geographical differentiation:strong tiller type only in Jiangsu,large leaf type in South China and Central China and large grain type mainly in North China.Weedy rice seriously infested rice fields and had a geography,climate and cultivated rice type-dependent morphological and biotype differentiation in China.It is suggested to pay attention to the harmfulness of weedy rice and adopt comprehensive control strategies.展开更多
Sorghum is an important food crop in Eritrea where it is widely grown in the mid and low lands,of semi-arid regions.Eritrea being the center of origin of sorghum,a large variability exist in its landraces being ...Sorghum is an important food crop in Eritrea where it is widely grown in the mid and low lands,of semi-arid regions.Eritrea being the center of origin of sorghum,a large variability exist in its landraces being grown by the farmers since generations.In order to improve the productivity of sorghum under moisture stress conditions,it is imperative to evaluate these landraces for drought tolerant characteristics and their use for further crop improvement programmes.Therefore,a field study was conducted in a randomized complete block design with three replications to estimate the extent of genetic variability of 20 sorghum genotypes for moisture stress tolerance using various morphological,phenological,yield and yield related parameters under rainfed conditions at Hagaz Research Station.Significant difference was observed for almost all the characters in the individual analysis of variance suggesting that these sorghum accessions were highly variable.Accessions EG 537,EG 1257,EG 849,EG 791,EG 783 and EG 813 showed promising results for post flowering drought tolerance,grain yield and stay green traits.Higher PCV and GCV were also obtained in parameters like plant height,leaf area,biomass,peduncle exertion,panicle length,and grain yield and panicle weight.The genotypes also exhibited varying degrees of heritability estimates.Characters such as plant height,panicle length,days to flowering and maturity showed higher heritability.Cluster analysis revealed that sorghum landraces were grouped on the basis of their morphological traits and geographical sites.77.3%of the total variation of sorghum landraces was contributed by the first four principal components analysis having Eigen value>1.Overall,the current study confirmed that EG 537,EG 849,EG 1257,EG 791,and EG 813 are drought tolerant sorghum landraces during post flowering stage.展开更多
The aim of this research was to assess the diversity of the Cameroon cotton zone in soybean associated rhizobia in order to formulate the most efficient elite inoculant to boost both the cotton and soybean production....The aim of this research was to assess the diversity of the Cameroon cotton zone in soybean associated rhizobia in order to formulate the most efficient elite inoculant to boost both the cotton and soybean production. Therefore, soybean associated rhizobia were isolated and characterized morphologically, physiologically and biochemically on YEMA culture media. For each of the two soybean varieties (Houla1 and TGX1910 14F) used, the trials were laid out in two IRAD-fields of North Cameroon (Sanguere-Paul) and Far-North (Soukoundou) respectively, under a complete randomized complete block design, the isolate formulations representing the treatments. The six isolated strains (IS1, IS2, IS3, IS4, IS5, IS6) from which seven liquid inoculant were formulated were revealed to belong to the same slow growing group of rhizobia, with a high level of tolerance to temperature, pH, and salinity, with optimum growth at respectively 28˚C, pH (7 - 9), salt (1% - 5%). Not surprisingly, root nodules were formed by both inoculated and uninoculated soybean plants. However, the most efficient soybean-rhizobia symbiosis for nodulations were isolate IS6 associated to TGX1910 14F variety, and isolate IS5 associated to Houla1variety at Sanguere-Paul. Whereas isolate M was associated to TGX1910 14F variety, Houla 1 variety had affinity with native rhizobia isolates at Soukoundou. The present results suggest the adaptability of rhizobia isolates to a particular soybean variety at a particular cotton fields zone. These findings should be taken into consideration for commercial inoculant formulation.展开更多
Objective: To investigate the composition of volatile compounds in the different accessions of Perilla frutescens(P. frutescens) collected from various habitats of China and Japan. Methods: In the present study, the e...Objective: To investigate the composition of volatile compounds in the different accessions of Perilla frutescens(P. frutescens) collected from various habitats of China and Japan. Methods: In the present study, the essential oil from the leaves of P. frutescens cultivars from China and Japan was extracted by hydro-distillation and the chemical composition and concentration of the volatile components present in the oils were determined by gas chromatography–mass spectrometry(GC–MS) analysis. Results: Among the volatile components, the major proportion was of perilla ketone, which was followed by elemicin and beta-caryophyllene in the Chinese Perilla cultivars. The main component in the oil extracted from the Japanese accessions was myristicin, which was followed by perilla ketone and beta-caryophyllene. We could distinguish seven chemotypes, namely the perilla ketone(PK) type, perilla ketone, myristicin(PM) type, perilla ketone, unknown(PU) type, perilla ketone, beta-caryophyllene, myristicine(PB) type, perilla ketone, myristicin, unknown(PMU) type, perilla ketone, elemicine, myristicin, beta-caryophyllene(PEMB) type, and the perilla ketone, limonene, betacryophyllene, myristicin(L) type. Most of the accessions possessed higher essential oil content before the flowering time than at the flowering stage. The average plant height, leaf length, leaf width of the Chinese accessions was higher than those of the Japanese accessions. Conclusion:The results revealed that the harvest time and geographical origin caused polymorphisms in the essential oil composition and morphological traits in the Perilla accessions originating from China and Japan. Therefore, these chemotypes with desirable characters might be useful for industrial exploitation and for determining the harvest time.展开更多
Weedy plants affect the biodiversity and ecosystem function as well as the crop and fodder plant production. However, adequate management requires detailed knowledge of the taxonomic identity of these plants. Here, we...Weedy plants affect the biodiversity and ecosystem function as well as the crop and fodder plant production. However, adequate management requires detailed knowledge of the taxonomic identity of these plants. Here, we focused on a hemiparasitic Pedicularis species(Orobanchaceae), which occurs at high densities and results in significant biomass reductions in forage grasses in Bayanbulak Grassland of Xinjiang. The identity of this target species is not clear, with conflicting reports in publications and in herbarium collections. Hence, clear and management-relevant information on demography and reproductive ecology is difficult to be obtained from the literature. Therefore, we analyzed field and archival materials collected from Xinjiang in order to clarify the identity and distribution of the target species. Morphological analyses suggested that the populations at Bayanbulak Grassland should be Pedicularis kansuensis Maxim. rather than P. verticillata L. which has been accepted in the available literature. Phylogenetic analysis with a combination of three barcodes(mat K, rbc L and trn H-psb A) uniting a clade of P. kansuensis and individuals from Bayanbulak Grassland populations with 100% bootstrap support, confirmed the target species to be P. kansuensis. Anatomical investigations and field observations showed that the target species is an annual or biennial herb, which also fits with the life cycle as P. kansuensis. Based on archive material and field observations, we verified that the distribution of P. kansuensis is mainly concentrated in the Tianshan Mountains of Xinjiang.展开更多
This study was conducted in selected sites of District Bahawalnagar namely,Shaheed Chowk,Chak40/F,Chak 163/7 R and Fareedkot Tiba between March 2019 and August 2019.Sampling techniques included recording of burrows,fl...This study was conducted in selected sites of District Bahawalnagar namely,Shaheed Chowk,Chak40/F,Chak 163/7 R and Fareedkot Tiba between March 2019 and August 2019.Sampling techniques included recording of burrows,flooding,burrow exaction,noose traps and pit fall traps were used to capture Uromast yx hardwickii.During this survey150 individuals were captured from study area for morphological measurement and population estimation.The average snout to vent length(SVL)of male,female and juveniles were(172.50±19.71)mm,(155.50±18.72)mm and(86.25±11.72)mm respectively.The average weight of male,female and juvenile was(93.06±8.56)g,(88.16±7.95)g and(40.16±4.30)g respectively.The relative abundance(Pi)of males,females and juveniles were 0.53,0.33 and 0.13.Indian spiny tailed lizard(U.hardwickii)has been listed in the IUCN Red list and CITES.Major threats to the species in the study area are increase in urbanization,habitat fragmentation,illegal hunting for meat and fat.In this regard strict implementation of the Wildlife act is needed to protect the wildlife of Punjab.Furthermore,comprehensive surveys are required in throughout Punjab to declare conservation status of U.hardwickii.展开更多
The pit morphology and growth kinetics of commercially pure aluminium in naturally aerated NaCl solutions were studied using an image processing method based on reflected light microscopy. In order to distinguish betw...The pit morphology and growth kinetics of commercially pure aluminium in naturally aerated NaCl solutions were studied using an image processing method based on reflected light microscopy. In order to distinguish between pits and pre-existing cavities, metallographic examination and statistical analysis were carried out before and after corrosion testing. The results show that the pit shapes and sizes are more dependent on the immersion time than the chloride concentration. Pits are predominantly hemispherical, but they undergo reasonable geometric transitions associated with increased immersion time and occur without significant depth variation. The role of chloride ions is more closely associated with the pit nucleation phenomenon.展开更多
Several hydrogels were synthesized by free-radical polymerization in an aqueous medium based on potato starch(PS),poly(vinyl alcohol)(PVA),and N,N′-Methylenebisacrylamide(MBAm),being possible to study these hydrogels...Several hydrogels were synthesized by free-radical polymerization in an aqueous medium based on potato starch(PS),poly(vinyl alcohol)(PVA),and N,N′-Methylenebisacrylamide(MBAm),being possible to study these hydrogels as a function of the proportion of components incorporated.In this way,the products generated from the synthesis were characterized by swelling and deswelling kinetics,the first swelling being verified with Schott and statistical models,allowing to contrast the proximity between the experimental and theoretical behavior.Additionally,water retention in soil(R%),spectroscopy(FTIR),morphological(SEM),and thermal(TGA and DSC)analysis allowing to know the intrinsic characteristics of the material,increasing in general terms the knowledge of this type of material.In this context,it was possible to verify the characteristics and effectiveness of the synthesis and crosslinking of the main components.The experimental results obtained show that the synthesized hydrogels present representative swellings consistent with kinetic and statistical models,optimal thermal stability depending on the amount of crosslinker,and excellent water retention in environments such as soil,presenting it as an excellent alternative to be used in agro-industrial applications in an eco-friendly way.展开更多
The morphology of graded crushed stone(GCS)particles has an essential influence on the performance of aggregate mixtures.The impact of particle shape is a comprehensive effect that cannot be considered separately,lead...The morphology of graded crushed stone(GCS)particles has an essential influence on the performance of aggregate mixtures.The impact of particle shape is a comprehensive effect that cannot be considered separately,leading to difficulties in establishing the relationship between the mixture properties and the aggregate morphology by using laboratory methods.The discrete element method(DEM)is an effective way widely adopted to reconstruct the morphology of particles and simulate performance tests of granular materials.However,selecting limited particles characterizing a real particle-assembly for simulation is still a challenge in current research due to the inherent rich variability of particle shapes.In this study,based on the acquisition of three-dimensional(3D)aggregate shapes by using laser scanning,ellipsoid index(EDI)translating the particle shape as a function of surface area,volume,and contour length is proposed to comprehensively evaluate aggregate morphology.Further,a particle library capable of characterizing aggregate morphology distribution is established based on the statistics of the corresponding morphological characteristics of particle samples.The model reliability is validated by carrying out a series of experimental and numerical penetration tests with nine different gradations.The established particle library can be used to model aggregate mixtures and the proposed simulation framework is promising for optimizing the mixture gradation design numerically.展开更多
To study the relations of certain morphological and sugar quality characters with sugarcane yield, an experiment was conducted at Wonji and Metehara Sugar Estates, Ethiopia between March 2012 and October 2013. The exp...To study the relations of certain morphological and sugar quality characters with sugarcane yield, an experiment was conducted at Wonji and Metehara Sugar Estates, Ethiopia between March 2012 and October 2013. The experiment, comprising of 400 sugarcane genotypes of which 174 were local that were collected from different regional states of Ethiopia and 226 introduced, was laid out in partial balanced lattice design with two replications. Data was collected on cane yield and its components, sugar yield and sugar quality traits. ANOVA, correlation and path coefficient analysis were done. Analysis of variance revealed significant differences (P < 0.01) for all the characters studied. Cane yield showed strong positive and highly significant (P < 0.01) correlation with millable cane number (r = 0.832), single cane weight (r = 0.528), stalk height (r = 0.517) and sugar yield (r = 0.987). There was also positive significant (P = 0.05) correlation of tiller count and cane diameter with cane yield. Path analysis revealed the highest positive direct effect of millable cane number (0.812) on cane yield followed by single cane weight (0.682) and pol percent (0.550). However, stalk diameter and brix percent had considerable negative direct effects and indirect positive effects through single cane weight on cane yield. Therefore, in view of their significant positive association with cane yield, indirect effects of stalk diameter and brix percent via single cane weight should be considered during selection. Genotypes should be selected on the basis of millable cane number, single cane weight and pol percent for getting higher cane and sugar yield.展开更多
The relationship between six </span><i><span style="font-family:Verdana;">Abutilon</span></i><span style="font-family:Verdana;"> species was examined using diffe...The relationship between six </span><i><span style="font-family:Verdana;">Abutilon</span></i><span style="font-family:Verdana;"> species was examined using different taxonomic investigation tools. The investigation was carried out using morphological and numerical studies. Fresh materials of </span><i><span style="font-family:Verdana;">Abutilon</span></i><span style="font-family:Verdana;"> species were collected from different localities in Saudi Arabia during 2018 and 2019. Numerical analysis was based on the Principle Coordinates, the Principle Component and the Unweighted Pair Group Method with Arithmetic Algorithm Clustering. The results indicated that there were significant differences based on the morphological characters especially in the leaves, fruits and flowers features. Morphometric studies revealed that the six species of </span><i><span style="font-family:Verdana;">Abutilon</span></i><span style="font-family:Verdana;"> clearly separated in all different analysis.展开更多
Botanical morphological characteristics of Physalis alkekengi L.is first introduced,and its medicinal and edible value is elaborated.Cultivation techniques of P.alkekengi L.are mainly introduced.The research aims to p...Botanical morphological characteristics of Physalis alkekengi L.is first introduced,and its medicinal and edible value is elaborated.Cultivation techniques of P.alkekengi L.are mainly introduced.The research aims to provide a certain basis for the better development and application of P.alkekengi L.展开更多
A set of evaluation indicators based on corrosion ratio in theory for assessing the extent of pitting corrosion and performance reduction are proposed. In order to quantify the morphology of pitting corrosion and extr...A set of evaluation indicators based on corrosion ratio in theory for assessing the extent of pitting corrosion and performance reduction are proposed. In order to quantify the morphology of pitting corrosion and extract the evaluation indicators,the 3D profile data obtained by pitting morphology measurement are imported into a special written program to automatically determine the location of each corrosion pit and distill any desired data pertinent to the pitting morphology. The results show that this method seems to be effective to analyze the corroded surface and characterize the pitting morphology.展开更多
In-situ maintenance is of great significance for improving the efficiency and ensuring the safety of aero-engines.The cable-driven continuum robot(CDCR)with twin-pivot compliant mechanisms,which is enabled with flexib...In-situ maintenance is of great significance for improving the efficiency and ensuring the safety of aero-engines.The cable-driven continuum robot(CDCR)with twin-pivot compliant mechanisms,which is enabled with flexible deformation capability and confined space accessibility,has emerged as a novel tool that aims to promote the development of intelligence and efficiency for in-situ aero-engine maintenance.The high-fidelity model that describes the kinematic and morphology of CDCR lays the foundation for the accurate operation and control for in-situ maintenance.However,this model was not well addressed in previous literature.In this study,a general kinetostatic modeling and morphology characterization methodology that comprehensively contains the effects of cable-hole friction,gravity,and payloads is proposed for the CDCR with twin-pivot compliant mechanisms.First,a novel cable-hole friction model with the variable friction coefficient and adaptive friction direction criterion is proposed through structure optimization and kinematic parameter analysis.Second,the cable-hole friction,all-component gravities,deflection-induced center-of-gravity shift of compliant joints,and payloads are all considered to deduce a comprehensive kinetostatic model enabled with the capacity of accurate morphology characterization for CDCR.Finally,a compact continuum robot system is integrated to experimentally validate the proposed kinetostatic model and the concept of in-situ aero-engine maintenance.Results indicate that the proposed model precisely predicts the morphology of CDCR and outperforms conventional models.The compact continuum robot system could be considered a novel solution to perform in-situ maintenance tasks of aero-engines in an invasive manner.展开更多
Mushrooms in the basidiomycete family Boletaceae are ecologically and economically very important.However,due to the morphological complexity and the limited phylogenetic information on the various species and genera ...Mushrooms in the basidiomycete family Boletaceae are ecologically and economically very important.However,due to the morphological complexity and the limited phylogenetic information on the various species and genera of this fungal family,our understanding of its systematics and evolution remains rudimentary.In this study,DNA sequences of four genes(nrLSU,tef1-α,rpb1,and rpb2)were newly obtained from ca.200 representative specimens of Boletaceae.Our phylogenetic analyses revealed seven major clades at the subfamily level,namely Austroboletoideae,Boletoideae,Chalciporoideae,Leccinoideae,Xerocomoideae,Zangioideae,and the Pulveroboletus Group.In addition,59 genus-level clades were identified,of which 22 were uncovered for the first time.These 22 clades were mainly placed in Boletoideae and the Pulveroboletus Group.The results further indicated that the characters frequently used in the morphology-based taxonomy of Boletaceae,such as basidiospore ornamentation,the form of the basidioma,and the stuffed pores each had multiple origins within the family,suggesting that the use of such features for high-level classification of Boletaceae should be de-emphasized and combined with other characters.展开更多
Inaccurate taxonomic placement of fossils can lead to the accumulation of errors in molecular clock studies and their generated evolutionary lineages.There are limited fossil data that can be used in divergence time e...Inaccurate taxonomic placement of fossils can lead to the accumulation of errors in molecular clock studies and their generated evolutionary lineages.There are limited fossil data that can be used in divergence time estimations.Therefore,reliable morphological characterization and taxonomical identification of fossil fungi are extremely important.Most fossils of Dothideomycetes and Sordariomycetes are from the early Cenozoic(66-23 Mya),with fewer from the late Mesozoic(174-145 Mya).However,it is hard to distinguish some fossil descriptions as photographs and illustrations are unclear;thus,the validity of using these fossils in calibrations of molecular clocks is problematic.This study brings scattered paleobiological data on selected fossil Ascomycota,using descriptions,fossil images and illustrations,coupled with recent age estimations,and taxonomic and phylogenetic affinity of extant species.As an integrated approach,this study summarizes a historical fossil outline with a reliable minimum age for 16 calibrating points viz.crown of Aigialus,Anzia,Aspergillus,Asterina,Calicium chlorosporum–C.nobile,Capnodiales,Chaenotheca,Colletotrichum,Diaporthales,Meliola,Ophiocordyceps,Microthyriales,Microthyrium,Muyocopron,Pezizomycotina and Stigmatomyces.A scheme of Ascomycota ancient lineages is also provided in order to improve divergence time estimations.展开更多
基金supported by the Major Scientific and Technological Project of Hainan Province,China(ZDKJ202002)the China Transgenic Organism Research and Commercialization Project(2016ZX08011-001)the National Key Research and Development Program of China(2016YFD0200805).
文摘Rice,the main food crop in China,has been sporadically reported to suffer from weedy rice infestation.However,the overall occurrence and distribution pattern of Chinese weedy rice remains unclear because a systematic survey has not been conducted.In order to reveal the infestation of Chinese weedy rice,a field survey was conducted in 999 sampling sites all over the rice-growing regions in China from 2009 to 2016 using seven-scale visual scoring of the level of weed infestation.Weedy rice was found 39%occurrence incidence in a total of 387 sites.The sampling sites with 50%or higher overall weedy rice infestation index mainly radiated from Jiangsu,Heilongjiang,Ningxia and Guangdong to the whole East China,Northeast China,Northwest China and South China.A total of 45 morphological characters from 287 populations(collected simultaneously with the field survey)out of those occurred sites were observed and analyzed using multivariate analysis in common gardens with the same cultivation conditions in 2017 and 2019.Canonical correlation analysis showed that 45 morphological characters were significantly related to the latitude,mean temperature,minimum temperature,precipitation and mean diurnal range factors.The 287 weedy rice populations were divided into three morphological groups with climate-dependent geographical differentiation:strong tiller type only in Jiangsu,large leaf type in South China and Central China and large grain type mainly in North China.Weedy rice seriously infested rice fields and had a geography,climate and cultivated rice type-dependent morphological and biotype differentiation in China.It is suggested to pay attention to the harmfulness of weedy rice and adopt comprehensive control strategies.
文摘Sorghum is an important food crop in Eritrea where it is widely grown in the mid and low lands,of semi-arid regions.Eritrea being the center of origin of sorghum,a large variability exist in its landraces being grown by the farmers since generations.In order to improve the productivity of sorghum under moisture stress conditions,it is imperative to evaluate these landraces for drought tolerant characteristics and their use for further crop improvement programmes.Therefore,a field study was conducted in a randomized complete block design with three replications to estimate the extent of genetic variability of 20 sorghum genotypes for moisture stress tolerance using various morphological,phenological,yield and yield related parameters under rainfed conditions at Hagaz Research Station.Significant difference was observed for almost all the characters in the individual analysis of variance suggesting that these sorghum accessions were highly variable.Accessions EG 537,EG 1257,EG 849,EG 791,EG 783 and EG 813 showed promising results for post flowering drought tolerance,grain yield and stay green traits.Higher PCV and GCV were also obtained in parameters like plant height,leaf area,biomass,peduncle exertion,panicle length,and grain yield and panicle weight.The genotypes also exhibited varying degrees of heritability estimates.Characters such as plant height,panicle length,days to flowering and maturity showed higher heritability.Cluster analysis revealed that sorghum landraces were grouped on the basis of their morphological traits and geographical sites.77.3%of the total variation of sorghum landraces was contributed by the first four principal components analysis having Eigen value>1.Overall,the current study confirmed that EG 537,EG 849,EG 1257,EG 791,and EG 813 are drought tolerant sorghum landraces during post flowering stage.
文摘The aim of this research was to assess the diversity of the Cameroon cotton zone in soybean associated rhizobia in order to formulate the most efficient elite inoculant to boost both the cotton and soybean production. Therefore, soybean associated rhizobia were isolated and characterized morphologically, physiologically and biochemically on YEMA culture media. For each of the two soybean varieties (Houla1 and TGX1910 14F) used, the trials were laid out in two IRAD-fields of North Cameroon (Sanguere-Paul) and Far-North (Soukoundou) respectively, under a complete randomized complete block design, the isolate formulations representing the treatments. The six isolated strains (IS1, IS2, IS3, IS4, IS5, IS6) from which seven liquid inoculant were formulated were revealed to belong to the same slow growing group of rhizobia, with a high level of tolerance to temperature, pH, and salinity, with optimum growth at respectively 28˚C, pH (7 - 9), salt (1% - 5%). Not surprisingly, root nodules were formed by both inoculated and uninoculated soybean plants. However, the most efficient soybean-rhizobia symbiosis for nodulations were isolate IS6 associated to TGX1910 14F variety, and isolate IS5 associated to Houla1variety at Sanguere-Paul. Whereas isolate M was associated to TGX1910 14F variety, Houla 1 variety had affinity with native rhizobia isolates at Soukoundou. The present results suggest the adaptability of rhizobia isolates to a particular soybean variety at a particular cotton fields zone. These findings should be taken into consideration for commercial inoculant formulation.
基金supported by funding from the Konkuk University Brain Pool
文摘Objective: To investigate the composition of volatile compounds in the different accessions of Perilla frutescens(P. frutescens) collected from various habitats of China and Japan. Methods: In the present study, the essential oil from the leaves of P. frutescens cultivars from China and Japan was extracted by hydro-distillation and the chemical composition and concentration of the volatile components present in the oils were determined by gas chromatography–mass spectrometry(GC–MS) analysis. Results: Among the volatile components, the major proportion was of perilla ketone, which was followed by elemicin and beta-caryophyllene in the Chinese Perilla cultivars. The main component in the oil extracted from the Japanese accessions was myristicin, which was followed by perilla ketone and beta-caryophyllene. We could distinguish seven chemotypes, namely the perilla ketone(PK) type, perilla ketone, myristicin(PM) type, perilla ketone, unknown(PU) type, perilla ketone, beta-caryophyllene, myristicine(PB) type, perilla ketone, myristicin, unknown(PMU) type, perilla ketone, elemicine, myristicin, beta-caryophyllene(PEMB) type, and the perilla ketone, limonene, betacryophyllene, myristicin(L) type. Most of the accessions possessed higher essential oil content before the flowering time than at the flowering stage. The average plant height, leaf length, leaf width of the Chinese accessions was higher than those of the Japanese accessions. Conclusion:The results revealed that the harvest time and geographical origin caused polymorphisms in the essential oil composition and morphological traits in the Perilla accessions originating from China and Japan. Therefore, these chemotypes with desirable characters might be useful for industrial exploitation and for determining the harvest time.
基金funded by the National Natural Science Foundation of China (U1303201, 31370512, 31400440)the Youth Innovation Promotion Association of Chines Academy of Sciences+2 种基金the Stiftung zur F?rderung der Pflanzenkenntnis (Basel/CH Foundation for the Promotion of Plant Knowledge)the US National Science Foundation (DEB-1119098)
文摘Weedy plants affect the biodiversity and ecosystem function as well as the crop and fodder plant production. However, adequate management requires detailed knowledge of the taxonomic identity of these plants. Here, we focused on a hemiparasitic Pedicularis species(Orobanchaceae), which occurs at high densities and results in significant biomass reductions in forage grasses in Bayanbulak Grassland of Xinjiang. The identity of this target species is not clear, with conflicting reports in publications and in herbarium collections. Hence, clear and management-relevant information on demography and reproductive ecology is difficult to be obtained from the literature. Therefore, we analyzed field and archival materials collected from Xinjiang in order to clarify the identity and distribution of the target species. Morphological analyses suggested that the populations at Bayanbulak Grassland should be Pedicularis kansuensis Maxim. rather than P. verticillata L. which has been accepted in the available literature. Phylogenetic analysis with a combination of three barcodes(mat K, rbc L and trn H-psb A) uniting a clade of P. kansuensis and individuals from Bayanbulak Grassland populations with 100% bootstrap support, confirmed the target species to be P. kansuensis. Anatomical investigations and field observations showed that the target species is an annual or biennial herb, which also fits with the life cycle as P. kansuensis. Based on archive material and field observations, we verified that the distribution of P. kansuensis is mainly concentrated in the Tianshan Mountains of Xinjiang.
文摘This study was conducted in selected sites of District Bahawalnagar namely,Shaheed Chowk,Chak40/F,Chak 163/7 R and Fareedkot Tiba between March 2019 and August 2019.Sampling techniques included recording of burrows,flooding,burrow exaction,noose traps and pit fall traps were used to capture Uromast yx hardwickii.During this survey150 individuals were captured from study area for morphological measurement and population estimation.The average snout to vent length(SVL)of male,female and juveniles were(172.50±19.71)mm,(155.50±18.72)mm and(86.25±11.72)mm respectively.The average weight of male,female and juvenile was(93.06±8.56)g,(88.16±7.95)g and(40.16±4.30)g respectively.The relative abundance(Pi)of males,females and juveniles were 0.53,0.33 and 0.13.Indian spiny tailed lizard(U.hardwickii)has been listed in the IUCN Red list and CITES.Major threats to the species in the study area are increase in urbanization,habitat fragmentation,illegal hunting for meat and fat.In this regard strict implementation of the Wildlife act is needed to protect the wildlife of Punjab.Furthermore,comprehensive surveys are required in throughout Punjab to declare conservation status of U.hardwickii.
基金This research was supported by FUNDUNESP(process 01258/2008 and 00601/2011-DFP)CNPq(processes 305224/2004-2 and 307271/2007-2).
文摘The pit morphology and growth kinetics of commercially pure aluminium in naturally aerated NaCl solutions were studied using an image processing method based on reflected light microscopy. In order to distinguish between pits and pre-existing cavities, metallographic examination and statistical analysis were carried out before and after corrosion testing. The results show that the pit shapes and sizes are more dependent on the immersion time than the chloride concentration. Pits are predominantly hemispherical, but they undergo reasonable geometric transitions associated with increased immersion time and occur without significant depth variation. The role of chloride ions is more closely associated with the pit nucleation phenomenon.
基金Concytec-Peru and the World Bank for the financial support of this project under the call“Mejoramiento y Ampliación de los Servicios del Sistema Nacional de Ciencia Tecnología e Innovación Tecnológica”8682-PE,through Fondecyt Grant 017-2019 FONDECYT BM INC.INV.
文摘Several hydrogels were synthesized by free-radical polymerization in an aqueous medium based on potato starch(PS),poly(vinyl alcohol)(PVA),and N,N′-Methylenebisacrylamide(MBAm),being possible to study these hydrogels as a function of the proportion of components incorporated.In this way,the products generated from the synthesis were characterized by swelling and deswelling kinetics,the first swelling being verified with Schott and statistical models,allowing to contrast the proximity between the experimental and theoretical behavior.Additionally,water retention in soil(R%),spectroscopy(FTIR),morphological(SEM),and thermal(TGA and DSC)analysis allowing to know the intrinsic characteristics of the material,increasing in general terms the knowledge of this type of material.In this context,it was possible to verify the characteristics and effectiveness of the synthesis and crosslinking of the main components.The experimental results obtained show that the synthesized hydrogels present representative swellings consistent with kinetic and statistical models,optimal thermal stability depending on the amount of crosslinker,and excellent water retention in environments such as soil,presenting it as an excellent alternative to be used in agro-industrial applications in an eco-friendly way.
基金supported by Shandong Hi-speed Group Co.,Ltd.Maintenance Technology Project(grant no.2017B61)National Natural Science Foundation of China(no.52108393)+1 种基金the Fundamental Research Funds for the Central Universities,CHD(no.300102211307)China Scholarship Council(no.201806560055).
文摘The morphology of graded crushed stone(GCS)particles has an essential influence on the performance of aggregate mixtures.The impact of particle shape is a comprehensive effect that cannot be considered separately,leading to difficulties in establishing the relationship between the mixture properties and the aggregate morphology by using laboratory methods.The discrete element method(DEM)is an effective way widely adopted to reconstruct the morphology of particles and simulate performance tests of granular materials.However,selecting limited particles characterizing a real particle-assembly for simulation is still a challenge in current research due to the inherent rich variability of particle shapes.In this study,based on the acquisition of three-dimensional(3D)aggregate shapes by using laser scanning,ellipsoid index(EDI)translating the particle shape as a function of surface area,volume,and contour length is proposed to comprehensively evaluate aggregate morphology.Further,a particle library capable of characterizing aggregate morphology distribution is established based on the statistics of the corresponding morphological characteristics of particle samples.The model reliability is validated by carrying out a series of experimental and numerical penetration tests with nine different gradations.The established particle library can be used to model aggregate mixtures and the proposed simulation framework is promising for optimizing the mixture gradation design numerically.
文摘To study the relations of certain morphological and sugar quality characters with sugarcane yield, an experiment was conducted at Wonji and Metehara Sugar Estates, Ethiopia between March 2012 and October 2013. The experiment, comprising of 400 sugarcane genotypes of which 174 were local that were collected from different regional states of Ethiopia and 226 introduced, was laid out in partial balanced lattice design with two replications. Data was collected on cane yield and its components, sugar yield and sugar quality traits. ANOVA, correlation and path coefficient analysis were done. Analysis of variance revealed significant differences (P < 0.01) for all the characters studied. Cane yield showed strong positive and highly significant (P < 0.01) correlation with millable cane number (r = 0.832), single cane weight (r = 0.528), stalk height (r = 0.517) and sugar yield (r = 0.987). There was also positive significant (P = 0.05) correlation of tiller count and cane diameter with cane yield. Path analysis revealed the highest positive direct effect of millable cane number (0.812) on cane yield followed by single cane weight (0.682) and pol percent (0.550). However, stalk diameter and brix percent had considerable negative direct effects and indirect positive effects through single cane weight on cane yield. Therefore, in view of their significant positive association with cane yield, indirect effects of stalk diameter and brix percent via single cane weight should be considered during selection. Genotypes should be selected on the basis of millable cane number, single cane weight and pol percent for getting higher cane and sugar yield.
文摘The relationship between six </span><i><span style="font-family:Verdana;">Abutilon</span></i><span style="font-family:Verdana;"> species was examined using different taxonomic investigation tools. The investigation was carried out using morphological and numerical studies. Fresh materials of </span><i><span style="font-family:Verdana;">Abutilon</span></i><span style="font-family:Verdana;"> species were collected from different localities in Saudi Arabia during 2018 and 2019. Numerical analysis was based on the Principle Coordinates, the Principle Component and the Unweighted Pair Group Method with Arithmetic Algorithm Clustering. The results indicated that there were significant differences based on the morphological characters especially in the leaves, fruits and flowers features. Morphometric studies revealed that the six species of </span><i><span style="font-family:Verdana;">Abutilon</span></i><span style="font-family:Verdana;"> clearly separated in all different analysis.
文摘Botanical morphological characteristics of Physalis alkekengi L.is first introduced,and its medicinal and edible value is elaborated.Cultivation techniques of P.alkekengi L.are mainly introduced.The research aims to provide a certain basis for the better development and application of P.alkekengi L.
基金Sponsored by the National Natural Science Foundation of China(Grant No.51378417)Program for Changjiang Scholars and Innovative Research Team in University(IRT13089)PhD Innovation Fund of Xi'an University of Architecture and Technology
文摘A set of evaluation indicators based on corrosion ratio in theory for assessing the extent of pitting corrosion and performance reduction are proposed. In order to quantify the morphology of pitting corrosion and extract the evaluation indicators,the 3D profile data obtained by pitting morphology measurement are imported into a special written program to automatically determine the location of each corrosion pit and distill any desired data pertinent to the pitting morphology. The results show that this method seems to be effective to analyze the corroded surface and characterize the pitting morphology.
基金sponsored by the National Natural Science Foundation of China(Grant Nos.52105117,52375125,and 52105118).
文摘In-situ maintenance is of great significance for improving the efficiency and ensuring the safety of aero-engines.The cable-driven continuum robot(CDCR)with twin-pivot compliant mechanisms,which is enabled with flexible deformation capability and confined space accessibility,has emerged as a novel tool that aims to promote the development of intelligence and efficiency for in-situ aero-engine maintenance.The high-fidelity model that describes the kinematic and morphology of CDCR lays the foundation for the accurate operation and control for in-situ maintenance.However,this model was not well addressed in previous literature.In this study,a general kinetostatic modeling and morphology characterization methodology that comprehensively contains the effects of cable-hole friction,gravity,and payloads is proposed for the CDCR with twin-pivot compliant mechanisms.First,a novel cable-hole friction model with the variable friction coefficient and adaptive friction direction criterion is proposed through structure optimization and kinematic parameter analysis.Second,the cable-hole friction,all-component gravities,deflection-induced center-of-gravity shift of compliant joints,and payloads are all considered to deduce a comprehensive kinetostatic model enabled with the capacity of accurate morphology characterization for CDCR.Finally,a compact continuum robot system is integrated to experimentally validate the proposed kinetostatic model and the concept of in-situ aero-engine maintenance.Results indicate that the proposed model precisely predicts the morphology of CDCR and outperforms conventional models.The compact continuum robot system could be considered a novel solution to perform in-situ maintenance tasks of aero-engines in an invasive manner.
基金supported by the Funds for International Cooperation and Exchange of the National Natural Science Foundation of China(31210103919)the National Basic Research Program of China(2014CB138305)the CAS/SAFEA International Partnership Program for Creative Research Teams.
文摘Mushrooms in the basidiomycete family Boletaceae are ecologically and economically very important.However,due to the morphological complexity and the limited phylogenetic information on the various species and genera of this fungal family,our understanding of its systematics and evolution remains rudimentary.In this study,DNA sequences of four genes(nrLSU,tef1-α,rpb1,and rpb2)were newly obtained from ca.200 representative specimens of Boletaceae.Our phylogenetic analyses revealed seven major clades at the subfamily level,namely Austroboletoideae,Boletoideae,Chalciporoideae,Leccinoideae,Xerocomoideae,Zangioideae,and the Pulveroboletus Group.In addition,59 genus-level clades were identified,of which 22 were uncovered for the first time.These 22 clades were mainly placed in Boletoideae and the Pulveroboletus Group.The results further indicated that the characters frequently used in the morphology-based taxonomy of Boletaceae,such as basidiospore ornamentation,the form of the basidioma,and the stuffed pores each had multiple origins within the family,suggesting that the use of such features for high-level classification of Boletaceae should be de-emphasized and combined with other characters.
基金The National Natural Science Foundation of China(NSFC 31600032)is acknowledged for funding this research workthe Mushroom Research Foundation(MRF),Chiang Mai,Thailand for providing a Postgraduate Scholarship+2 种基金the Grants entitled"The future of specialist fungi in a changing climate:baseline data for generalist and specialist fungi associated with ants,Rhododendron species and Dracaena species"(Grant No:DBG6080013)"Impact of climate change on fungal diversity and biogeography in the Greater Mekong Subregion"(Grant No:RDG6130001)for supporting this studypartially supported by Chiang Mai University.
文摘Inaccurate taxonomic placement of fossils can lead to the accumulation of errors in molecular clock studies and their generated evolutionary lineages.There are limited fossil data that can be used in divergence time estimations.Therefore,reliable morphological characterization and taxonomical identification of fossil fungi are extremely important.Most fossils of Dothideomycetes and Sordariomycetes are from the early Cenozoic(66-23 Mya),with fewer from the late Mesozoic(174-145 Mya).However,it is hard to distinguish some fossil descriptions as photographs and illustrations are unclear;thus,the validity of using these fossils in calibrations of molecular clocks is problematic.This study brings scattered paleobiological data on selected fossil Ascomycota,using descriptions,fossil images and illustrations,coupled with recent age estimations,and taxonomic and phylogenetic affinity of extant species.As an integrated approach,this study summarizes a historical fossil outline with a reliable minimum age for 16 calibrating points viz.crown of Aigialus,Anzia,Aspergillus,Asterina,Calicium chlorosporum–C.nobile,Capnodiales,Chaenotheca,Colletotrichum,Diaporthales,Meliola,Ophiocordyceps,Microthyriales,Microthyrium,Muyocopron,Pezizomycotina and Stigmatomyces.A scheme of Ascomycota ancient lineages is also provided in order to improve divergence time estimations.
