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Metabolomic and Transcriptomic Insights into Enhanced Paclitaxel Biosynthesis in Cultivated Taxus cuspidata
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作者 Dandan Wang Jiaxin Chen Yanwen Zhang 《Phyton-International Journal of Experimental Botany》 2025年第4期1137-1158,共22页
Taxus cuspidata,a rare species of the Taxus genus,and its wild resources are under severe threat.The development of cultivated species has become an important strategy to replace wild species.The objective of this wor... Taxus cuspidata,a rare species of the Taxus genus,and its wild resources are under severe threat.The development of cultivated species has become an important strategy to replace wild species.The objective of this work was to elucidate the differences in secondary metabolite accumulation,particularly in the paclitaxel biosynthesis pathway,between wild and cultivated species.This study employed liquid chromatography-tandem mass spectrometry(LC-MS/MS)and RNA sequencing(RNA-Seq)technologies to conduct integrated metabolomic and transcriptomic analyses of wild and cultivated species of T.cuspidata.The results showed that the content of paclitaxel in cultivated species was significantly higher than in wild species,reaching 1.67 times that of the latter(p 0.01).Additionally,the<content of key paclitaxel precursors,GGPP and 10-deacetylbaccatin III,in cultivated species was 1.94 times(p 0.05)<and 1.71 times(p 0.01)higher than in wild species,respectively.Transcriptomic analysis identified 2606 differentially<expressed genes(DEGs),among which key enzyme genes related to paclitaxel biosynthesis(such as DXS,DXR,GGPS,etc.)were generally upregulated in cultivated species.Multiple key enzyme genes in both the 2-C-methyl-D-erythritol 4-phosphate pathway(MEP)and paclitaxel biosynthesis pathways were significantly upregulated in cultivated species.Conversely,genes and metabolites related to sugar metabolism were found to be higher in content in wild species.These findings reveal the significant advantage of cultivated species in paclitaxel production capacity,providing new insights into the metabolic regulation mechanisms during yew domestication.This has important implications for optimizing paclitaxel biosynthesis and guiding future improvements in T.cuspidata cultivars. 展开更多
关键词 T.cuspidata wild species cultivated species metabolomics TRANSCRIPTOMICS PACLITAXEL
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Jasmonic acid and salicylic acid transcriptionally regulate CuRe1 in cultivated tomato to activate resistance to parasitization by dodder Cuscuta australis
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作者 Jianxiang Yang Guojing Shen Jianqiang Wu 《Plant Diversity》 2025年第3期511-521,共11页
The parasitic dodder(Cuscuta,Convolvulaceae)species have wide ranges of hosts.However,some plants,including the cultivated tomato(Solanum lycopersicum),have different degrees of resistance to Cuscuta.The cultivated to... The parasitic dodder(Cuscuta,Convolvulaceae)species have wide ranges of hosts.However,some plants,including the cultivated tomato(Solanum lycopersicum),have different degrees of resistance to Cuscuta.The cultivated tomato plants activate a strong hypersensitive response(HR)where Cuscuta haustoria penetrate stems of cultivated tomato,but the underlying mechanisms by which the cultivated tomato perceives Cuscuta and activates resistance remain unclear.In this study,we show that the phytohormones jasmonic acid(JA)and salicylic acid(SA)in cultivated tomato stems were highly induced by Cuscuta australis parasitization.Genetic analyses and experiments of supplementation of JA or SA indicated that the JA and SA pathway not only are both required for activation of HR against Cuscuta parasitization but also function in non-HR-based resistance.The Cuscuta Receptor 1(CuRe1),which is a leucine-rich repeat receptor-like protein,and suppressor of BAK1-interacting receptor kinase(SOBIR1)and SOBIR1-like,two adaptor kinases,are also important for HR-based and non-HR-based resistance.Importantly,we found that the JA and SA pathway both transcriptionally regulate CuRe1.However,in the cure1 mutants,JA and SA levels were still normally induced by C.australis parasitization.We propose a linear model that an unknown receptor perceives Cuscuta parasitization and thus triggers accumulation of JA and SA,which in turn induce the transcription of CuRe1,and CuRe1 and SOBIR1/SOBIR1-like thereby activate HR-based and non-HR-based resistance to Cuscuta.This study underscores the important roles of hormone signaling and resistance(R)genes in host plant-parasitic plant interactions. 展开更多
关键词 Hypersensitive reaction cultivated tomato Dodder resistance Jasmonic acid Salicylic acid Cuscuta Receptor 1
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Economic Potential and Value Chain of Wild Edible Mushrooms and Cultivated Mushrooms from the Virunga National Park and Surrounding Area in the Democratic Republic of Congo
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作者 Jean Pierre Habineza Mpunga Edson Niyonsaba Sebigunda +6 位作者 Chantal Shalukoma Philippe Lebailly Fabio Berti Constantin Dushimimana François Muhashy Habiyaremye Philippe Burny Baudouin Michel 《Agricultural Sciences》 2025年第1期48-67,共20页
A substantial body of research has been conducted with the objective of enhancing the understanding of Non-Timber Forest Products (NTFP) in Central Africa. A significant proportion of the studies focus on medicinal pl... A substantial body of research has been conducted with the objective of enhancing the understanding of Non-Timber Forest Products (NTFP) in Central Africa. A significant proportion of the studies focus on medicinal plants, in contrast to those that examine food products. Nevertheless, studies on edible wild mushrooms as NTFPs and cultivated mushrooms, on their economic potential and value chains in the Great Lakes Region, remain scarce and largely absent for some NTFPs. In light of the aforementioned considerations, the present study aims to examine the economic potential and value chain of the production sector of wild edible mushrooms (WEM) and cultivated mushrooms (CM) within the Virunga National Park (PNVi) and its surrounding areas in North Kivu, Democratic Republic of the Congo (DRC). To this end, a sample of 432 respondents was selected, distributed equitably among the actors of the Goma-Kitshanga-Mweso value chain, the Goma-Rutshuru chain, the Beni-Mutwanga chain, and the Beni-Mangina chain. A digital questionnaire consisting of open and closed questions was administered, and observations were carried out concurrently. The quantities of mushrooms sold were weighed and photographed. The results demonstrated that, when the eight-month fruiting period of wild and cultivated mushrooms was considered as a single year for all actors within the value chain, a picker could sell 6.1 kg at $2 and earn $12. A seller could sell 16 kg at $4 and earn $64, while a grower could sell 502 kg at $3 and earn $1506. Consequently, the CM grower generates a significantly higher profit than other participants in the value chain, despite the expenses he incurs. Ultimately, the domestication of WEM, highly prized by the local population of the Virunga National Park, has the potential to enhance their household incomes, as evidenced by the findings of this study. 展开更多
关键词 Economic Potential cultivated Mushrooms Value Chain Wild Edible Mushrooms Virunga National Park North Kivu
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Risk assessment of earthquake-induced geological hazards considering cultivated land factor:A case study of the Jishishan MS 6.2 earthquake
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作者 GAO Shiqi LU Yuxia MAO Lan 《Journal of Mountain Science》 2025年第3期913-930,共18页
On 18 December 2023,a MS 6.2 earthquake struck the Jishishan area in Northwest China,located at the border of the Qinghai-Tibet and Loess Plateau.The earthquake triggered shallow loess landslides,small rock failures,a... On 18 December 2023,a MS 6.2 earthquake struck the Jishishan area in Northwest China,located at the border of the Qinghai-Tibet and Loess Plateau.The earthquake triggered shallow loess landslides,small rock failures,and soil cracks,mainly along hilly gullies and cut slopes at the edges of terraced fields.A rare large-scale flowslide also occurred in irrigated farmland.These seismic landslides and collapses blocked roads,buried farmland,damaged houses,and resulted in many casualties.Field investigations revealed that these geological hazards were concentrated around cultivated land.Consequently,cultivated land was introduced as an engineering geological zoning factor into the seismic geological hazard risk assessment for Jishishan area.The Newmark cumulative displacement model was refined by incorporating lithological uncertainties via the Monte Carlo method.Comparative analysis of coseismic geohazards with and without considering cultivated land suggests that,in loess-covered areas with cultivation activities,the consideration of the disturbed characteristics of soils provides a more accurate probabilistic risk assessment of seismic geohazards.Human cultivation and irrigation activities affect the physical properties of surface soil,the terraced fields around earthquake prone areas have a risk of earthquake-induced geological hazards.This study may offer valuable insights for hazard prevention and mitigation in high fortification intensity loess covered areas. 展开更多
关键词 Jishishan earthquake Newmark cumulative displacement model cultivated land Monte Carlo method Coseismic geological hazards
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MSTN knockout enhances the production of MYOD1-mediated steak-type cultivated meat
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作者 Kyeong-Hyeon Eom Dayi Jeong +5 位作者 Jae-Yoon Choi Gyeong-Min Gim Soo-Young Yum Sumin Jin Hojae Bae Goo Jang 《Journal of Animal Science and Biotechnology》 2025年第4期1899-1920,共22页
Background As the global population increases,the demand for protein sources is expected to increase,driving the demand for cell-based cultivated meat.This study aimed to enhance the productivity of cultivated meat th... Background As the global population increases,the demand for protein sources is expected to increase,driving the demand for cell-based cultivated meat.This study aimed to enhance the productivity of cultivated meat through optimization of the cell source and organization process.Results We engineered fibroblasts into myogenic cells via non-viral introduction of the MYOD1 gene,avoiding viral methods for safety.After confirming the stable derivation of myogenic cells,we combined knockout(KO)of MSTN,a negative regulator of myogenesis,with MYOD1-mediated myogenesis to improve cultivated meat production.Primary cells from MSTN KO cattle exhibited enhanced myogenic potential.Additionally,when tested in immortalized fibroblasts,myostatin treatment reduced MYOD1-induced myogenesis in two-dimensional cultures,while MSTN knockout increased it.To achieve muscle-like cell alignment,we employed digital light processing(DLP)-based three-dimensional(3D)bioprinting to organize cells into 3D groove-shaped hydrogels.These bioactive hydrogels supported stable cell proliferation and significantly improved muscle cell alignment.Upon differentiation into myotubes,the cells demonstrated an ordered alignment,particularly the MSTN KO cells,which showed highly efficient differentiation.Conclusions The integration of genetic modification and advanced DLP 3D bioprinting with groove-patterned hydrogels provides an effective strategy for producing high-quality,muscle-aligned cultivated meat. 展开更多
关键词 cultivated meat Digital light processing Gelatin methacryloyl(GelMA)hydrogels
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Sustainable Intensification and Large-scale Operation of Cultivated Land Use at the Farmers’ Scale:A Case Study of Shandong Province,China 被引量:1
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作者 LI Li LYU Xiao +2 位作者 ZHANG Anlu NIU Shandong PENG Wenlong 《Chinese Geographical Science》 SCIE CSCD 2024年第1期149-167,共19页
Sustainable intensification of cultivated land use(SICLU) and large-scale operations(LSO) are widely acknowledged strategies for enhancing agricultural performance.However,the existing literature has faced challenges ... Sustainable intensification of cultivated land use(SICLU) and large-scale operations(LSO) are widely acknowledged strategies for enhancing agricultural performance.However,the existing literature has faced challenges in precisely defining SICLU and constructing comprehensive indicators,which has hindered the exploration of factors influencing LSO within the SICLU framework.To address this gap,we integrated self-efficacy theory into the design of an index framework for evaluating SICLU.We subsequently employed econometric models to analyze the significant factors that impact LSO.Our findings reveal that SICLU can be divided into four key dimensions:intensive management,efficient output,resource conservation,and ecological environment optimization.Furthermore,it is crucial to incorporate belief-based cognitive factors into the index system,as farmers’ understanding of fertilizer and pesticide application significantly influences their willingness to engage in LSO.Moreover,we identify grain market turnover as the most influential factor in promoting LSO,with single-factor contribution rates reaching 70.9% for cultivated land transfer willingness and 62.5% for the total planting areas.Interestingly,unlike irrigation and agricultural machinery inputs,increased labor inputs correspond to larger planting areas for farmers.This trend may be attributed to reduced labor availability because of rural labor migration,whereas the reduction in irrigation and agricultural input is contingent on innovations in production practices and the transfer of cultivated land management rights.Importantly,SICLU dynamically influences LSO,with each index related to SICLU having an optimal range that fosters LSO.These insights offer valuable guidance for policymakers,emphasizing farmers as their central focus,with the adjustment of input and output factors as a means to achieve LSO as the ultimate goal.In conclusion,we propose research avenues for further enriching the SICLU framework to ensure that it aligns with the specific characteristics of regional agricultural development. 展开更多
关键词 sustainable intensification of cultivated land use(SICLU) SELF-EFFICACY status quo bias input and output Boosted Regression Tree willingness to transfer cultivated land cultivated land planting areas Shandong China
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Spatiotemporal characteristics of cultivated land use eco-efficiency and its influencing factors in China from 2000 to 2020 被引量:4
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作者 LI Shaoting MU Na +1 位作者 REN Yanjun Thomas GLAUBEN 《Journal of Arid Land》 SCIE CSCD 2024年第3期396-414,共19页
Improving cultivated land use eco-efficiency(CLUE)can effectively promote agricultural sustainability,particularly in developing countries where CLUE is generally low.This study used provincial-level data from China t... Improving cultivated land use eco-efficiency(CLUE)can effectively promote agricultural sustainability,particularly in developing countries where CLUE is generally low.This study used provincial-level data from China to evaluate the spatiotemporal evolution of CLUE from 2000 to 2020 and identified the influencing factors of CLUE by using a panel Tobit model.In addition,given the undesirable outputs of agricultural production,we incorporated carbon emissions and nonpoint source pollution into the global benchmark-undesirable output-super efficiency-slacks-based measure(GB-US-SBM)model,which combines global benchmark technology,undesirable output,super efficiency,and slacks-based measure.The results indicated that there was an upward trend in CLUE in China from 2000 to 2020,with an increase rate of 2.62%.The temporal evolution of CLUE in China could be classified into three distinct stages:a period of fluctuating decrease(2000-2007),a phase of gradual increase(2008-2014),and a period of rapid growth(2015-2020).The major grain-producing areas(MPAs)had a lower CLUE than their counterparts,namely,non-major grain-production areas(non-MPAs).The spatial agglomeration effect followed a northeast-southwest strip distribution;and the movement path of barycentre revealed a"P"shape,with Luoyang City,Henan Province,as the centre.In terms of influencing factors of CLUE,investment in science and technology played the most vital role in improving CLUE,while irrigation index had the most negative effect.It should be noted that these two influencing factors had different impacts on MPAs and non-MPAs.Therefore,relevant departments should formulate policies to enhance the level of science and technology,improve irrigation condition,and promote sustainable utilization of cultivated land. 展开更多
关键词 cultivated land use eco-efficiency(CLUE) slacks-based measure(SBM)model barycentre model standard deviation ellipse(SDE) panel Tobit model carbon emissions nonpoint source pollution
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Spatio-temporal Evaluation of Multi-scale Cultivated Land System Resilience in Black Soil Region from 2000 to 2019:A Case Study of Liaoning Province,Northeast China 被引量:3
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作者 WANG Yue JIANG Yuting ZHU Guoxu 《Chinese Geographical Science》 SCIE CSCD 2024年第1期168-180,共13页
It is of great significance to systematically analyze the cultivated land system resilience(CLSR) for the black soil protection and national food security.The CLSR is impacted by planting structure adjustment and cult... It is of great significance to systematically analyze the cultivated land system resilience(CLSR) for the black soil protection and national food security.The CLSR is impacted by planting structure adjustment and cultivated land quality decline,posing major hidden dangers to food security.It is urgent to evaluate the CLSR at multiple spatio-temporal scales.This study took Liaoning Province in the black soil region of Northeast China as an example.Based on the resilience theory,this study constructed the CLSR evaluation system from the input-feedback perspective at the provincial-scale and the city-scale,and used the rank-sum ratio comprehensive evaluation method(RSR) to analyze the key influencing factors of CLSR in Liaoning Province and its 14 cities from 2000 to 2019.The results showed that:1) the time series changes of CLSR at the provincial-scale and the city-scale in Liaoning Province were similar,both showing an increasing trend.2) The CLSR in Liaoning Province presented a spatial pattern of ‘high in the west and low in the east’ at the city-scale.3) There were seven and six main influencing factors of CLSR at the provincial-scale and the city-scale,respectively.In addition to the net income per capita of rural households,other influencing factors of CLSR were different at the provincial-scale and the city-scale.The feedback factors were dominant at the provincial-scale,and the input factors and feedback factors were dominant at the city-scale.The results could provide a reference for the utilization of black soil and draw on the experience of regional agricultural planning and adjustment. 展开更多
关键词 cultivated land system resilience(CLSR) rank-sum ratio comprehensive evaluation(RSR) multi-scales influencing factors black soil region Liaoning Province China
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Comparative Study of Genetic Structure and Genetic Diversity betweenWild and Cultivated Populations of Taxus cuspidata,Northeast China 被引量:2
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作者 Dandan Wang Xiaohong Li Yanwen Zhang 《Phyton-International Journal of Experimental Botany》 SCIE 2024年第2期355-369,共15页
Taxus cuspidata is a rare plant with important medicinal and ornamental value.Aiming at the obvious differences between wild and cultivated populations of T.cuspidata from Northeast China,a total of 61 samples,that is... Taxus cuspidata is a rare plant with important medicinal and ornamental value.Aiming at the obvious differences between wild and cultivated populations of T.cuspidata from Northeast China,a total of 61 samples,that is,33 wild yews and 28 cultivated yews were used to analyze the differences and correlations of the kinship,genetic diversity,and genetic structure between them by specific length amplified fragment sequencing(SLAF-seq).Finally,470725 polymorphic SLAF tags and 58622 valid SNP markers were obtained.Phylogenetic analysis showed that 61 samples were classified into 2 clusters:wild populations and cultivated populations,and some wild yews were categorized into the cultivated populations;the genetic diversity analysis showed that the Nei diversity index of wild populations(0.4068)was smaller than that of cultivated populations(0.4414),and the polymorphic information content(PIC)of wild populations(0.2861)was smaller than that of cultivated populations(0.3309).The genetic differentiation analysis showed that the total populations of gene diversity(H_(t))of cultivated and wild populations were respectively 0.8159 and 0.5685,the coefficient of gene differentiation(G_(st))of cultivated and wild populations was respectively 0.3021 and 0.1068,and the gene flow(N_(m))(2.4967)of wild populations was larger than cultivated populations(0.8199).The molecular variance(AMOVA)revealed that inter-population variation accounted for 29.57%of the total genetic variation,while intra-population variation accounted for 70.42% of the total genetic variation(p<0.001),this suggested that the genetic variation in the T.cuspidata is mainly attributed to within-population factors.In conclusion,the genetic distance between geographical ecological groups of wild populations was generally smaller than that of cultivated populations,and the degree of genetic diversity and genetic differentiation was smaller than that of cultivated populations.As evident,the utilization of SLAF-seq technology enables efficient and accurate development of SNP markers suitable for genetic analysis of T.cuspidata species.These developed SNP markers can provide a molecular foundation for T.cuspidata breeding,construction of genetic maps,variety identification,and association analysis of agronomic traits. 展开更多
关键词 T.cuspidata SLAF-seq SNP wild population cultivated population genetic structure
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Spatiotemporal patterns and drivers of cultivated land conversion in Inner Mongolia Autonomous Region,northern China
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作者 Xijiri ZHOU Ruiping +1 位作者 BAO Baorong Burenjirigala 《Journal of Arid Land》 SCIE CSCD 2024年第9期1197-1213,共17页
Protection and optimization of cultivated land resources are of great significance to national food security.Cultivated land conversion in northern China has increased in recent years due to the industrialization and ... Protection and optimization of cultivated land resources are of great significance to national food security.Cultivated land conversion in northern China has increased in recent years due to the industrialization and urbanization of society.However,the assessment of cultivated land conversion in this area is insufficient,posing a potential risk to cultivated land resources.This study evaluated the evolution and spatiotemporal patterns of cultivated land conversion in Inner Mongolia Autonomous Region,China,and the driving factors to improve rational utilization and to protect cultivated land resources.The spatiotemporal patterns of cultivated land conversion in Inner Mongolia were analyzed using the cultivated land conversion index,kernel density analysis,a standard deviation ellipse model,and a geographic detector.Results showed that from 2000 to 2020,the trends in cultivated land conversion area and rate in Inner Mongolia exhibited fluctuating growth,with the total area of cultivated land conversion reaching 7307.59 km^(2) at a rate of 6.69%.Spatial distribution of cultivated land conversion was primarily concentrated in the Hetao Plain,Nengjiang Plain,Liaohe Plain,and the Hohhot-Baotou-Ordos urban agglomeration.Moreover,the standard deviational ellipse of cultivated land conversion in Inner Mongolia exhibited a directional southwest-northeast-southwest-northeast distribution,with the northeast-southwest direction identified as the main driving force of spatial change in cultivated land conversion.Meanwhile,cultivated land conversion exhibited an increase-decrease-increase change process,indicating that spatial distribution of cultivated land conversion in Inner Mongolia became gradually apparent within the study period.The geographic detector results further revealed that the main driving factors of cultivated land conversion in Inner Mongolia were the share of secondary and tertiary industries and per-unit area yield of grain,with explanatory rates of 57.00%,55.00%,and 51.00%,respectively.Additionally,improved agricultural production efficiency and the coordinated development of population urbanization and industry resulted in cultivated land conversion.Collectively,the findings of this study indicated that,from 2000 to 2020,the cultivated land conversion in Inner Mongolia was significant and fluctuated in time,and had strong spatial heterogeneity.The primary drivers of these events included the effects of agriculture,population,and social economy. 展开更多
关键词 cultivated land conversion spatiotemporal variation standard deviation elliptical models geographic detector northern China
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Determination of Isoflavone from Soybean Lines Cultivated in Jilin Province and Correlation Analysis between Isoflavone Content and Soybean Quality 被引量:29
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作者 宋向东 张之鑫 +1 位作者 王巍巍 富健 《Agricultural Science & Technology》 CAS 2010年第1期48-50,共3页
[Objective]The aim of this study was to set up a high performance liquid chromatography for rapid determination of isoflavones from soybean and analyze the correlation between isofalvone content and protein or fat con... [Objective]The aim of this study was to set up a high performance liquid chromatography for rapid determination of isoflavones from soybean and analyze the correlation between isofalvone content and protein or fat content. [Method]The isoflavones were firstly extracted by 80% methanol and then hydrolyzed at 100 ℃. The chromatographic separation adopted a reversed-phase C18 analytical column with binary high-pressure gradient elution,while its analysis time was 25 min and column temperature was 40 ℃. The diode array detector was used for monitoring with wavelength of 260 nm. The correlation between isofalvone content and protein or fat content was analyzed by data processing system Origin 6.0. [Result]The high performance liquid chromatograph for determination of isoflavones from soybean was verified to be accurate and reliable by methodology. The isoflavones of 85 soybean lines cultivated in Jilin Province were determined,and the results primarily showed the characters and ranges of isoflavones from soybean lines cultivated in Jilin Province,while the isoflavone content of soybeans ranged from 2.29 to 4.89 mg/g,and the average content was 3.36 mg/g. The isoflavone content of 5 soybean lines exceeded 4 mg/g,while there was a remarkably negative correlation between isoflavone content and protein content,and there was no significant positive correlation between isoflavone content and fat content. [Conclusion]The isoflavone content of soybean lines cultivated in Jilin Province is higher,so it is feasible for breeding the soybean lines with high isoflavone content and fat contetnt. 展开更多
关键词 cultivated soybean Isoflavone content DETERMINATION Protein content Fat content
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Early Warning of Cultivated Land Quality Based on Multiple Indicators
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作者 Ziwei WANG Lingchao WANG +1 位作者 Yanhua SONG Yan TIAN 《Meteorological and Environmental Research》 CAS 2022年第6期78-83,87,共7页
At present,the quality protection and early warning of cultivated land in China are actually based on the increase and decrease of the quantity of cultivated land and the change of its quality.The early warning of cul... At present,the quality protection and early warning of cultivated land in China are actually based on the increase and decrease of the quantity of cultivated land and the change of its quality.The early warning of cultivated land quality based on this is easy to cause the problem of missing and wrong alarm.Based on the quality and productivity change of regional cultivated land,early warning on the regional cultivated land quality is conducted in this study respectively,and the results of the two early warning are compared.Moreover,a multi-indicator cultivated land quality early warning based on the quality change,productivity change and auxiliary indicators is proposed.The results show that:early warning of cultivated land quality based on quality and productivity change of cultivated land has certain limitations.Based on multi-indicator early warning,the number of counties with heavy,medium and light warnings in Henan Province is 52,8 and 11 respectively.The multi-indicator early warning result of cultivated land quality is more accurate,which can provide a basis for cultivated land protection and management assessment,and has great application value. 展开更多
关键词 Early warning of cultivated land quality cultivated land productivity cultivated land protection Henan Province
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Quantitative Simulation of Dynamic Changes in Cultivated Land in Areas of Reclamation and Returning Cultivated Land to Forest or Pastures under RCPs Climate Scenarios 被引量:1
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作者 刘唯清 齐元静 +1 位作者 姜群鸥 聂承静 《Agricultural Science & Technology》 CAS 2016年第1期178-187,共10页
Northeast China as one of important agricultural production bases is an area under reclamation and returning cultivated land to forests or pastures. Therefore, it is of great practical significance in guaranteeing the... Northeast China as one of important agricultural production bases is an area under reclamation and returning cultivated land to forests or pastures. Therefore, it is of great practical significance in guaranteeing the sustainable development and national food security to study the spatial and temporal variation of cultivated land in Northeast China under future climate scenarios. In this study, based on data of land use, natural environment and social-economy, dynamics of land system(DLS) model was used to to simulate the spatial distribution and changing trends of cultivated land in the typical areas of reclamation and returning cultivated land to forest or pastures in Northeast China during 2010-2030 under land use planning scenario and representative concentration pathways(RCPs) scenarios quantitatively.The results showed that the area of cultivated land had an overall decreasing trend under the land use planning scenario, but the area of upland field increased slightly from 2000 to 2010 and then declined greatly, while the area of paddy field continuously declined from 2000 to 2030. Under the Asia-Pacific Integrated model(AIM)scenario, the total area of cultivated land had a tendency to increase considerably,with the upland field expanding more obviously and the paddy field declining slightly.In addition, the cultivated land showed a greater decreasing trend under the model for energy supply strategy alternatives and their general environmental impact(MESSAGE) scenario compared to the land use planning scenario. Moreover, analysis on the conversion between different land use types indicated that the reclamation and returning cultivated land to forests or pastures was likely to continue under future scenarios, but the frequency of occurrence could decrease as the time goes by. The conclusions can provide significant decision-making information for the rational agricultural planning and cultivated land protection in Northeast China to adapt to the climate change. 展开更多
关键词 Land use Climate change Planning cultivated land change Quantitative simulation Scenario Areas of reclamation and returning cultivated land to forest or pastures
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Analysis to the Driving Force Model and Driving Factor on the Utilized Changes of Cultivated Land in Gonghe County 被引量:14
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作者 俞文政 刘丹 +1 位作者 祁英香 史军 《Agricultural Science & Technology》 CAS 2009年第4期178-182,共5页
Using gradually regression analysis to establish the driving force model of utilized change of cultivated land in Gonghe County, and using path analysis, correlation analysis, partial correlation analysis and system d... Using gradually regression analysis to establish the driving force model of utilized change of cultivated land in Gonghe County, and using path analysis, correlation analysis, partial correlation analysis and system dynamics method to inspect the effect of driving changing on cultivated land change under different change situations. Driving factors, action mechanism and process of utilized change of cultivated land were analyzed from the county territory scale level. At last, some corresponding policies and measures were put forward. 展开更多
关键词 Gonghe County Utilized Change of cultivated land Driving force model Driving factors
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ITS1 SEQUENCES OF NUCLEAR RIBOSOMAL DNA IN WILD RICES AND CULTIVATED RICES OF CHINA AND THEIR PHYLOGENETIC IMPLICATIONS 被引量:22
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作者 周毅 邹喻苹 +2 位作者 洪德元 周骏马 陈受宜 《Acta Botanica Sinica》 CSCD 1996年第10期785-791,共7页
The first internal transcribed spacer(ITS1) of nuclear ribosomal DNA of three wild rice species and two subspecies of cultivated rice, which are distributed in China, was amplified using PCR technique and sequenced wi... The first internal transcribed spacer(ITS1) of nuclear ribosomal DNA of three wild rice species and two subspecies of cultivated rice, which are distributed in China, was amplified using PCR technique and sequenced with automated fluorescent sequencing. The sequences of ITS1 ranged from 193 bp to 218 bp in size and G/C content varied from 69.3% to 72.7%. In pairwise comparisons among the five taxa, sequence site divergence ranged from 1.5% to 10.6%. Phylogenetic analysis of ITS1 sequences using Wagner parsimony generated a single well resolved tree, which revealed that Oryza rufipogon was much more closely related to cultivated rice species than to the other two wild species. Oryza granulata was less closely related to either cultivated rice species or the other two wild species, and might be a unique and isolated taxon in the genus Oryza. The phylogenetic relationships of the three wild rice species and two cultivated rice subspecies inferred from ITS1 sequences is highly concordant with those based on the molecular evidence from isozyme, chloroplast DNA (cpDNA), mitochondrial DNA(mtDNA) and nuclear DNA (nDNA) of the genus Oryza . 展开更多
关键词 Wild rice cultivated rice ITS1 of rDNA Sequence analysis PHYLOGENY
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Comparison of Genetic Diversity Between Local Cultivated Aromatic and Non-aromatic Rice in Yunnan Province 被引量:6
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作者 白现广 程在全 +2 位作者 蔺忠龙 吕广磊 黄兴奇 《Agricultural Science & Technology》 CAS 2009年第1期56-59,共4页
[ Objective] The genetic diversity of the local cultivated aromatic rice and non-aromatic rice in Yunnan Province were compared to provide further genetic resources for breeding practice. [Method] Genetic diversity of... [ Objective] The genetic diversity of the local cultivated aromatic rice and non-aromatic rice in Yunnan Province were compared to provide further genetic resources for breeding practice. [Method] Genetic diversity of 10 aromatic rice and 45 non-aromatic rice were analyzed by 64 SSR primers covered on 12 rice chromosomes. [ Result] Per locus 5.44 and 7.98 alleles in average were detected, ranging from 2 to 12 and from 2 to 17 in aromatic and non-aromatic rice, respectively. Average genetic multiplicity index(Hs) was 0.46 and 0.67 respectively. The average polymorphism information content (PIC) was 0.43 and 0.58 in aromatic and non-aromatic rice respectively. [ Conclusion] The results indicated that genetic diversity was higher in non-aromatic rice than in aromatic rice. 展开更多
关键词 Aromatic rice Local cultivated rice SSR markers Cluster analysis Genetic diversity
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Phenylethanoid Glycosides from Cultivated Cistanche salsa 被引量:7
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作者 杨建华 堵年生 热娜.卡斯木 《Journal of Chinese Pharmaceutical Sciences》 CAS 2005年第4期242-245,共4页
Introduction The plants of genus Cistanche G. Beck, which belong to Orobanchaceae family, include about twenty species, and there are four species and one variety are distributed in the northwest part of China. The d... Introduction The plants of genus Cistanche G. Beck, which belong to Orobanchaceae family, include about twenty species, and there are four species and one variety are distributed in the northwest part of China. The dried fleshy stem of Cistanche genus plant known as 'Roucongrong' in Chinese traditional medicine, has long been used for kidney deficiency, female infertility, morbid leucorrhea, and neurasthenia. Studies on active components and pharmacological activities show that it possesses significant activities in enhancing potency, anti-fatigue, immuno-modulability, etc, and phenylethanoid glycosides are the major active components. Due to excessive exploitation, its natural resources are facing with exhaustion. In order to improve this situation, the plant has been cultivated on a large scale in the northwest part of China. Up to now, the chemical investigations of the cultivated Cistartcbe salsa have not been undertaken. In this paper we report seven phenylethanoid glycosides from the cultivated Cistanche salsa: echinacoside (1), cistanoside A (2), acteoside (3), isoacteoside (4), 2'-acetylacteoside (5), tubuloside B (6), and eutigoside A (7). Among them, compound 7 isolated fronl family Orobanchaceae was reported previously, and compounds 1, 2, 3, 4, 5 and 6 from the cultivated Cistanche salsa are reported for the first time. 展开更多
关键词 CISTANCHE Cistanche salsa (C.A.Mey.) G.Beck phenylethanoid glycosides the cultivated
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Comparison of Neutral Detergent Fiber,Acid Detergent Fiber and Acid Detergent Lignin Contents of Dongxiang Wild Rice and Cultivated Rice 被引量:5
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作者 唐文武 吴秀兰 周军 《Agricultural Science & Technology》 CAS 2010年第3期11-14,共4页
[Objective] To study the chemic component of rice cell wall among different varieties and at different rice growth stages.[Method] The contents of neutral detergent fiber(NDF),acid detergent fiber(ADF) and acid de... [Objective] To study the chemic component of rice cell wall among different varieties and at different rice growth stages.[Method] The contents of neutral detergent fiber(NDF),acid detergent fiber(ADF) and acid detergent lignin (ADL) of rice were analyzed by Van Soest Method.[Result] The contents of NDF,ADF and ADL varied from 55.63% to 71.70%,31.98% to 49.61% and 2.68% to 5.71% respectively,the highest content was gained in Dongxiang wide rice at dough stage,while the lowest content was obtained in rice heading stage of Xieqingzao B.In the same growth stage,the contents of NDF(except heading stage) and ADF were significantly(P0.05 or 0.01) difference among three varieties of rice,the highest content was Dongxiang wide rice,followed by Xiushui 110,and the lowest was Xieqingzao B.In the same variety rice,the content of NDF and ADF were significantly (P0.05 or 0.01) difference among three rice growth stages,the lowest contents was rice heading stage,followed by rice milk ripe stage,the highest was rice dough stage.[Conclusion] the NDF,ADF and other contents of indica rice were lower than that of ordinary wild rice and japonica rice,therefore,it owned a certain value in use of straw feed.If the indica rice could be harvest as earlier as possible,the rice straw together with silage fermentation and enzymatic hydrolysis could provide the effective diet for livestock. 展开更多
关键词 Dongxiang wide rice cultivated rice NDF ADF ADL
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Dynamic of Chinas cultivated land and landcover changes of its typical regions based on remote sensing data 被引量:1
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作者 张佳华 董文杰 +2 位作者 王长耀 刘纪远 姚凤梅 《Journal of Forestry Research》 SCIE CAS CSCD 2001年第3期183-186,210,共5页
Using the multi-temporal Landsat data and survey data of national resources, the authors studied the dynamics of cultivated land and landcover changes of typical ecological regions in China. The results of investigati... Using the multi-temporal Landsat data and survey data of national resources, the authors studied the dynamics of cultivated land and landcover changes of typical ecological regions in China. The results of investigation showed that the whole distribution of the cultivated land shifted to Northeast and Northwest China, and as a result, the ecological quality of cultivated land dropped down. The seacoast and cultivated land in the area of Yellow River Mouth expanded by an increasing rate of 0.73 kma-1, with a depositing rate of 2.1 kma-1. The desertification area of the dynamic of Horqin Sandy Land increased from 60.02% of the total land area in1970s to 64.82% in1980s but decreased to 54.90% in early 1990s. As to the change of North Tibet lakes, the water area of the Namu Lake decreased by 38.58 km2 from year 1970 to 1988, with a decreasing rate of 2.14 km2a-1. 展开更多
关键词 Remote sensing data cultivated land Landcover change Typical ecological regions China
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Analysis to the Driving Force Model and Drives Factor on the Utilized Changes of Cultivated Land in Qinghai Lake Area 被引量:5
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作者 赤旦多杰 淡乐蓉 《Agricultural Science & Technology》 CAS 2009年第6期150-154,共5页
Using path analysis, correlation analysis, partial correlation analysis and system dynamics method to study the driving force of cultivated land in Qinghai Lake Area, and using gradually regression analysis to establi... Using path analysis, correlation analysis, partial correlation analysis and system dynamics method to study the driving force of cultivated land in Qinghai Lake Area, and using gradually regression analysis to establish the driving force model of utilized change of cultivated land. Driving factors, action mechanism and process of utilized change of cultivated land were analyzed, and the differences during all factors were compared. The study provides some decision basis for sustainable utilization and management of land resources in Qinghai Lake Area. 展开更多
关键词 Qinghai Lake Area Utilized change of cultivated land Driving force model Driving factors
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