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Agro-Morphological Variability in Eight Bambara Groundnut (Vigna subterranea (L.) Verdc.) Morphotypes from Zinder (Niger)
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作者 Oumarou Zango Rabiou Abdou +2 位作者 Saley Adamou Salamatou Agbo So Timothée Kouassi Bakasso Yacoubou 《Agricultural Sciences》 CAS 2023年第1期1-10,共10页
Bambara groundnut (Vigna subterranea (L.) Verdc.) has economic importance for the producers and the traders as cash crop since it generates substantial income for households in Niger. The objective of this study was t... Bambara groundnut (Vigna subterranea (L.) Verdc.) has economic importance for the producers and the traders as cash crop since it generates substantial income for households in Niger. The objective of this study was to assess eight (8) Bambara groundnut morphotype from Université André Salifou de Zinder in Niger Republic by their morphological and agronomic characters. The experiment was conducted in a randomized complete block design with three replications during the rainy season of 2020-2021. Data were collected on the Number of leaves, Plant height (cm), Growth habit (cm), Terminal leaflet length, Terminal leaflet width, Number of nodes/stem, Number of stems/plant, Number of pods/plant, Weight of 100 pods (g), Weight of 100 seeds (g), Length of seeds (mm), Width of seeds (mm), Weight of seeds/Plot (kg). There were significant differences for all characters, except Number of leaves, Terminal leaflet length, Terminal leaflet width, Length of seeds (mm) Weight of 100 pods (g), Weight of 100 seeds (g). The morphotypes UZ-VZ-04, UZ-VZ-03, UZ-VZ-06, UZ-VZ-02 and UZ-VZ-05 have demonstrated good performance for grain weight per plot and can be useful for a breeding program. 展开更多
关键词 Vigna subterranea ACCESSIONS agro-morphological Traits Weight of 100 Seeds
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Strong Laws of Large Numbers for Sequences of Blockwise m-Dependent and Sub-Orthogonal Random Variables under Sublinear Expectations 被引量:1
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作者 Jialiang FU 《Journal of Mathematical Research with Applications》 2026年第1期103-118,共16页
In this paper,we establish some strong laws of large numbers,which are for nonindependent random variables under the framework of sublinear expectations.One of our main results is for blockwise m-dependent random vari... In this paper,we establish some strong laws of large numbers,which are for nonindependent random variables under the framework of sublinear expectations.One of our main results is for blockwise m-dependent random variables,and another is for sub-orthogonal random variables.Both extend the strong law of large numbers for independent random variables under sublinear expectations to the non-independent case. 展开更多
关键词 sublinear expectations strong law of large numbers blockwise m-dependent suborthogonal random variables
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Global Existence and Blow-up of Solutions for Fourth-order Parabolic Equation with p(x)-Laplacian and Variable Exponents
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作者 YANG Chunxiao YU Lifei DUAN Chenyan 《数学进展》 北大核心 2026年第1期221-239,共19页
In this paper,we consider the fourth-order parabolic equation with p(x)Laplacian and variable exponent source ut+∆^(2)u−div(|■u|^(p(x)−2■u))=|u|^(q(x))−1u.By applying potential well method,we obtain global existence... In this paper,we consider the fourth-order parabolic equation with p(x)Laplacian and variable exponent source ut+∆^(2)u−div(|■u|^(p(x)−2■u))=|u|^(q(x))−1u.By applying potential well method,we obtain global existence,asymptotic behavior and blow-up of solutions with initial energy J(u_(0))≤d.Moreover,we estimate the upper bound of the blow-up time for J(u_(0))≤0. 展开更多
关键词 fourth-order parabolic equation variable exponent source global existence asymptotic behavior BLOW-UP
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Enhanced moisture-sensitivity increased the growth variability of Picea purpurea in the northeastern Tibetan Plateau
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作者 Wenxin Yu Bo Wang +2 位作者 Tuo Chen Guobao Xu Guoju Wu 《Journal of Forestry Research》 2026年第2期213-223,共11页
Tree growth variability is a key determinant of forest stabilities.Previous studies have shown that recent climate change has increased variability in tree growth,while others have challenged this viewpoint,leading to... Tree growth variability is a key determinant of forest stabilities.Previous studies have shown that recent climate change has increased variability in tree growth,while others have challenged this viewpoint,leading to ongoing debate in this field.Moreover,gaps remain in understanding the climatic mechanisms driving increased tree growth variability,particularly for species simultaneously limited by multiple climate factors.In this study,we assessed the temporal trends in variability of Picea purpurea radial growth and its linkage with growth-climate sensitivity utilizing dendrochronological methods.Our results revealed a significant increase in P.purpurea radial growth variability from 1960 to 2020,as indicated by continuous rises in the standard deviation,coefficient of variation,and mean sensitivity of tree-ring width indices.The increased frequency of extreme growth declines further supported this finding.Furthermore,moisture condition in July was identified as a key limiting factor of P.purpurea growth.Notably,the strengthening relationship between tree-ring width indices and vapor pressure deficit(VPD)suggests that the moisture sensitivity for P.purpurea growth has increased over the period 1960-2020.This enhanced sensitivity to VPD,whose interannual variability has also increased synchronously,may have contributed to the rise in P.purpurea growth variability.Additionally,the maximum temperature in May was positively correlated with P.purpurea growth;however,there is little evidence that this factor contributed to the observed increase in growth variability.These findings provide new insights into P.purpurea growth trends and improve our understanding of the potential future impacts of climate change on forest ecosystems. 展开更多
关键词 Tree growth variability Growth-climate response TREE-RING Picea purpurea
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Research Progress on Spatiotemporal Variability of Rice Planting Based on Satellite Remote Sensing Monitoring
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作者 Qi ang HU Aichuan LI +2 位作者 Xinbing WANG Francesco Marinello Zhan SHI 《Agricultural Biotechnology》 2026年第1期76-81,共6页
As a vital food crop,rice is an important part of global food crops.Studying the spatiotemporal changes in rice cultivation facilitates early prediction of production risks and provides support for agricultural policy... As a vital food crop,rice is an important part of global food crops.Studying the spatiotemporal changes in rice cultivation facilitates early prediction of production risks and provides support for agricultural policy decisions related to rice.With the increasing application of satellite remote sensing technology in crop monitoring,remote sensing for rice cultivation has emerged as a novel approach,offering new perspectives for monitoring rice planting.This paper briefly outlined the current research and development status of satellite remote sensing for monitoring rice cultivation both at home and abroad.Foreign scholars have made innovations in data sources and methodologies for satellite remote sensing monitoring,and utilized multi-source satellite information and machine learning algorithms to enhance the accuracy of rice planting monitoring.Scholars in China have achieved significant results in the study of satellite remote sensing for monitoring rice cultivation.Their research and application in monitoring rice planting areas provide valuable references for agricultural production management.However,satellite remote sensing monitoring of rice still faces challenges such as low spatiotemporal resolution and difficulties related to cloud cover and data fusion,which require further in-depth investigation.Additionally,there are shortcomings in the accuracy of remote sensing monitoring for fragmented farmland plots and smallholder farming.To address these issues,future efforts should focus on developing multi-source heterogeneous data fusion analysis technologies and researching monitoring systems.These advancements are expected to enable high-precision large-scale acquisition of rice planting information,laying a foundation for future smart agriculture. 展开更多
关键词 Satellite remote sensing Rice cultivation Spatiotemporal variability MONITORING Research review
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Thermo-mechanical damage behavior of the interface between hybrid alkali-resistant glass fiber-reinforced concrete and rock under high and variable temperature conditions
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作者 Cong Zhang Zhen Xu +4 位作者 Shanyong Wang Chong Shi Hui Wang Yonggang Zhang Guoqing Chen 《International Journal of Mining Science and Technology》 2026年第2期399-421,共23页
Thermal-mechanical damage and deformation at the interface between shotcrete linings and the surrounding rock of tunnels under high-temperature and variable-temperature conditions are critical to the safe construction... Thermal-mechanical damage and deformation at the interface between shotcrete linings and the surrounding rock of tunnels under high-temperature and variable-temperature conditions are critical to the safe construction and operation of tunnel engineering.This study investigated the thermo-mechanical damage behavior of the composite interface between alkali-resistant glass fiber-reinforced concrete(ARGFRC)and granite,focusing on a plateau railway tunnel.Laboratory triaxial tests,laser scanning,XRD analysis,numerical simulations,and theoretical analyses were employed to investigate how different initial curing temperatures and joint roughness coefficient(JRC)influence interfacial damage behavior.The results indicate that an increase in interface roughness exacerbates the structural damage at the interface.At a JRC of 19.9 and a temperature of 70℃,crack initiation in granite was notably restrained when the confining pressure rose from 7 MPa to 10 MPa.Roughness-induced stress distribution at the interface was notably altered,although this effect became less pronounced under high confining pressure conditions.Additionally,during high-temperature curing,thermal stress concentration at the tips of micro-convex protrusions on the granite surface induced microcracks in the adjacent ARGFRC matrix,followed by deformation.These findings provide practical guidelines for designing concrete support systems to ensure tunnel structural safety in high-altitude regions with harsh thermal environments. 展开更多
关键词 High and variable temperature ARGFRC-granite INTERFACE Thermo-mechanical coupling Damage evolution
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A TimeXer-Based Numerical Forecast Correction Model Optimized by an Exogenous-Variable Attention Mechanism
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作者 Yongmei Zhang Tianxin Zhang Linghua Tian 《Computers, Materials & Continua》 2026年第3期1770-1785,共16页
Marine forecasting is critical for navigation safety and disaster prevention.However,traditional ocean numerical forecasting models are often limited by substantial errors and inadequate capture of temporal-spatial fe... Marine forecasting is critical for navigation safety and disaster prevention.However,traditional ocean numerical forecasting models are often limited by substantial errors and inadequate capture of temporal-spatial features.To address the limitations,the paper proposes a TimeXer-based numerical forecast correction model optimized by an exogenous-variable attention mechanism.The model treats target forecast values as internal variables,and incorporates historical temporal-spatial data and seven-day numerical forecast results from traditional models as external variables based on the embedding strategy of TimeXer.Using a self-attention structure,the model captures correlations between exogenous variables and target sequences,explores intrinsic multi-dimensional relationships,and subsequently corrects endogenous variables with the mined exogenous features.The model’s performance is evaluated using metrics including MSE(Mean Squared Error),MAE(Mean Absolute Error),RMSE(Root Mean Square Error),MAPE(Mean Absolute Percentage Error),MSPE(Mean Square Percentage Error),and computational time,with TimeXer and PatchTST models serving as benchmarks.Experiment results show that the proposed model achieves lower errors and higher correction accuracy for both one-day and seven-day forecasts. 展开更多
关键词 TimeXer model exogenous variable attention mechanism sea surface temperature temporal-spatial features forecast correction
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A data-and expert-driven framework for establishing land cover-related essential variables for SDG monitoring and assessment
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作者 Hao Wu Ping Zhang +6 位作者 Jun Chen Songnian Li Jing Li Shu Peng Dongyang Hou Jun Zhang Hao Chen 《Geography and Sustainability》 2026年第1期236-246,共11页
Sustained and spatially explicit monitoring of the United Nations 2030 Agenda for Sustainable Development is critical for effectively tracking progress toward the global Sustainable Development Goals(SDGs).Although la... Sustained and spatially explicit monitoring of the United Nations 2030 Agenda for Sustainable Development is critical for effectively tracking progress toward the global Sustainable Development Goals(SDGs).Although land cover information has long been recognized as an essential component for monitoring SDGs,a standardized scientific framework for identifying and prioritizing land cover related essential variables does not exist.Therefore,we propose a novel expert-and data-driven framework for identifying,refining,and selecting a priority list of Essential Land cover-related Variables for SDGs(ELcV4SDGs).This framework integrates methods including expert knowledge-based analysis,clustering of variables with similar attributes,and quantified index calculation to establish the priority list.Applying the framework to 15 specific SDG indicators,we found that the ELcV4SDGs priority list comprises three main categories,type and structure,pattern and intensity,and process and evolution of land cover,which are further divided into 19 subcategories and ultimately encompass 50 general variables.The ELcV4SDGs will support detailed spatial monitoring and enhance their scientific applications for SDG monitoring and assessment,thereby guiding future SDG priority actions and informing decision-making to advance the 2030 SDGs agenda at local,national,and global levels. 展开更多
关键词 Essential variable Land cover SDG Spatial monitoring and assessment Interactive analysis Refinement and selection
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OptimizationDesign and Numerical Simulation of Variable Tube Diameter Heat Exchanger for Split Air Conditioning Indoor Unit
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作者 Zheming Cheng Xinping Ou Yang +2 位作者 Leren Tao Zihao Wang Ke Sun 《Frontiers in Heat and Mass Transfer》 2026年第1期288-313,共26页
Energy shortage has become one of themost concerning issues in the world today,and improving energy utilization efficiency is a key area of research for experts and scholars worldwide.Small-diameter heat exchangers of... Energy shortage has become one of themost concerning issues in the world today,and improving energy utilization efficiency is a key area of research for experts and scholars worldwide.Small-diameter heat exchangers offer advantages such as reduced material usage,lower refrigerant charge,and compact structure.However,they also face challenges,including increased refrigerant pressure drop and smaller heat transfer area inside the tubes.This paper combines the advantages and disadvantages of both small and large-diameter tubes and proposes a combined-diameter heat exchanger,consisting of large and small diameters,for use in the indoor units of split-type air conditioners.There are relatively few studies in this area.In this paper,A theoretical and numerical computation method is employed to establish a theoretical-numerical calculation model,and its reliability is verified through experiments.Using this model,the optimal combined diameters and flow path design for a combined-diameter heat exchanger using R32 as the working fluid are derived.The results show that the heat transfer performance of all combined diameter configurations improves by 2.79%to 8.26%compared to the baseline design,with the coefficient of performance(COP)increasing from 4.15 to 4.27~4.5.These designs can save copper material,but at the cost of an increase in pressure drop by 66.86%to 131.84%.The scheme IIIH,using R32,is the optimal combined-diameter and flow path configuration that balances both heat transfer performance and economic cost. 展开更多
关键词 Split air condition variable tube diameter enhanced heat transfer numerical simulation structural design optimization
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Spatiotemporal Variability of Influencing Factors on Tuberculosis Incidence in Jiangsu Province,China during 2011−2021
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作者 Yifan Tang Tenglong Li +7 位作者 Cheng Chen Kai Wang Mingming Chen Junhui Lin Sifan Wang Limei Zhu Chengxiu Ling Qiao Liu 《Biomedical and Environmental Sciences》 2026年第2期234-238,共5页
Tuberculosis(TB),one of the oldest infectious diseases caused by Mycobacterium tuberculosis,poses a considerable challenge to global public health.There are approximately 10 million new TB cases worldwide annually,and... Tuberculosis(TB),one of the oldest infectious diseases caused by Mycobacterium tuberculosis,poses a considerable challenge to global public health.There are approximately 10 million new TB cases worldwide annually,and TB claims the lives of nearly 3 million people each year,making it one of the leading causes of death from a single infectious disease[1].China ranks third globally in terms of TB burden,with approximately 733,000 TB cases reported in 2023[2].Based on the ecological model of health determinants developed by Whitehead and Dahlgren,health determinants can be classified into direct causes. 展开更多
关键词 tuberculosis incidence infectious diseases influencing factors mycobacterium tuberculosisposes spatiotemporal variability China ecological model health determinants jiangsu province
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Agro-Morphological Characterization of a Collection of Fonio [Digitaria exilis (Kippist.) Stapf.] Accessions from Burkina Faso
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作者 Balma Patrice Kabore Boukare +3 位作者 Kiebre Mariam Kiebre Zakaria Sanou Jacob Bationo/Kando Pauline 《American Journal of Plant Sciences》 2023年第6期677-690,共14页
Considered as the oldest cereal, fonio (Digitaria exilis Stapf.) is grown in West Africa for its therapeutic virtues, its nutritional and organoleptic qualities. It plays an important socio-cultural and economic role ... Considered as the oldest cereal, fonio (Digitaria exilis Stapf.) is grown in West Africa for its therapeutic virtues, its nutritional and organoleptic qualities. It plays an important socio-cultural and economic role for the populations of western Burkina Faso. However, very few studies on the genetic diversity of fonio have been carried out. This study aims to contribute to a better knowledge of the diversity of Digitaria exilis in Burkina Faso using agro-morphological descriptors. Thus, 60 accessions of fonio collected from western Burkina Faso were characterized using 21 agro-morphological characters according to an Alpha Latice design with three replications. The study showed morphological variability for most of the qualitative and quantitative characters studied. Principal component analysis (PCA) explained 56.07% of the variability. Hierarchical cluster analysis splits the accessions of the collection into four clusters using seven characters. These characters can constitute basic criteria for differentiating fonio accessions in Burkina Faso. The accessions of Group II have a long cycle and high production of grain, while the accessions of Group IV have a short cycle and low production of grain. The groups identified can serve as a starting point for fonio breeding in Burkina Faso. 展开更多
关键词 Digitaria exilis agro-morphological variability ACCESSION Burkina Faso
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Screening of Sapindus germplasm resources in China based on agro-morphological traits 被引量:1
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作者 Jiming Liu Shiqi Liu +9 位作者 Yuanyuan Xu Caowen Sun Zhong Chen Xin Wang Lixian Wang Shilun Gao Guochun Zhao Qiuyang He Xuehuang Weng Liming Jia 《Journal of Forestry Research》 SCIE CAS CSCD 2022年第1期203-216,共14页
Sapindus L.species are widely cultivated for biodiesel,biomedical,and biochemical raw materials in southern China.However,yields fuctuate widely due to the lack of high-yielding,high-quality,stable cultivars.Therefore... Sapindus L.species are widely cultivated for biodiesel,biomedical,and biochemical raw materials in southern China.However,yields fuctuate widely due to the lack of high-yielding,high-quality,stable cultivars.Therefore,the objectives of this study were to evaluate three species and one variety among 149 nationwide Sapindus species and screen for elite accessions which would serve as Sapindus breeding materials.Accessions were evaluated on 19 agro-morphological traits by correlation analysis and principal component analysis.These displayed substantial diversity and a broad range of economic traits.In particular,accessions of Sapindus mukorossi and Sapindus rarak had more variation in economic traits than Sapindus delavayi and Sapindus rarak var.velutinus.Increased saponin accumulation may be achieved at the cost of seed oil production.Thirty elite accessions for oil and saponin production,and for comprehensive utilization were screened and accessions no.80,110,and 112 had significant potential to produce high yields.These elite accessions will facilitate the identification of genetic determinants of valuable traits and the effective utilization of trait variability in Sapindus breeding. 展开更多
关键词 agro-morphological traits Germplasm resources Sapindus Principal component analysis
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Agro-Morphological Characterization of Cassava (Manihot esculenta Crantz) Cultivars from Chad 被引量:1
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作者 Djirabaye Nadjiam Papa Saliou Sarr +2 位作者 Michel Naïtormbaïdé Jean Marie Mbaïlao Mbaïguinam Aliou Guisse 《Agricultural Sciences》 2016年第7期479-492,共14页
Cassava is a considerable source of food and income for the rural community of the south of Chad. Despite the importance of the diversity of cultivars in situ, their morphological traits and agronomic performance are ... Cassava is a considerable source of food and income for the rural community of the south of Chad. Despite the importance of the diversity of cultivars in situ, their morphological traits and agronomic performance are under investigated. The aim of this study is to characterize and analyze the variability structure of the cassava’s germplasm. Fifty nine cultivars collected from five main cassava growing regions, were evaluated by forty five agro-morphological descriptors in a Fisher design replicated three times. Data were collected at three, six, nine and twelve months after planting. High phenotypic variability was shown within the collection for the color of apical leaf, vein leaf, petiole, roots and pulp. The same case was observed for the root peduncle, the shape of the central leaflet and the root, the cortex root thickness and the texture of root epidermis. Significant to highly significant differences were observed for all the quantitative traits. High variability were shown for the size of the leaf lobe, petiole length, plant height, root number and length, harvest index, above-ground biomass and fresh root weight. Positive correlations were found between the leaflet and leaf lobe number. Fresh root weight was also positively correlated to the root number, length and diameter. Principal component analysis (PCA) on quantitative variable revealed four groups with two of them containing performant cultivars: Group II with small root, high potential yield but less leaflet and leaf lobe and group III characterized by some cultivars with high productivity, more leaflet and leaf lobe, more and bigger roots. At regional level, significant differences were shown within cultivars which were discriminated in relation to their origin region by the number of the leaf lobes. The better cultivars and the interesting traits could be used to improve cassava production in Chad. 展开更多
关键词 variability TRAITS Cassava Cultivars LOCAL Improved CHAD
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Agro-Morphological Characterization and Genetic Dissection of Linseed(Linum usitatissimum L.)Genotypes 被引量:1
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作者 A.K.M.Golam Sarwar Md.Sabibul Haque +6 位作者 Md.Ekramul Haque Md.Amir Hossain Md.Golam Azam Md.Nesar Uddin Eldessoky S.Dessoky Mahmoud A.Basry Md.Alamgir Hossain 《Phyton-International Journal of Experimental Botany》 SCIE 2022年第8期1721-1743,共23页
Linseed is a multipurpose crop and the crop needs further improvement to increase production and yield due to its high value and demand.This study aimed to assess the extent and pattern of genetic variability of forty... Linseed is a multipurpose crop and the crop needs further improvement to increase production and yield due to its high value and demand.This study aimed to assess the extent and pattern of genetic variability of forty linseed genotypes based on diverse agro–morphological and yield attributes.The field experiment was conducted following a Randomized Complete Block Design with three replications.Linseed germplasm showed a wide range of phenotypic expression,genetic variability and heritability for 30 studied traits.A low to high phenotypic coeffi-cient of variation(PCV)and genotypic coefficient of variation(GCV)were observed.The lowest genotypic(σ2 g)and phenotypic variances(σ2 p)were found in capsule diameter(CD),length of calyx(LC),capsule length(CL),seed length(SL),and seed breadth(SB).High broad-sense heritability(h2 b)with high genetic advance as a percentage of mean(GAM)were observed in days to germination started(DGS),days to 80%emergence(DE),plant height at 28 and 40 DAS,number of flowers(NFPP),filled capsules(NFCPP)and yield per plant(YPP)indicating additive gene action exists for these characters.Hierarchical cluster analysis separated 40 genotypes into five clusters,where Clusters I to V assembled with 13,4,4,5 and 14 genotypes,respectively.Considering yield and yield attributes,Cluster-IV(G3,G4,G6,G10 and G31)genotypes showed promising while,Cluster-II(G2,G16,G35,G36)and Cluster-III(G1,G33,G39 and G40)genotypes were dominant on plant morphological traits.Based on principal component analysis(PCA),few characters such as YPP,NFPP,NFCPP,days to first flowering and capsule formation,early emergence,days to branch initiation and plant heights at different growth stages revealed important and effective traits for consideration in the selection of linseed breeding programs. 展开更多
关键词 Genetic variability HERITABILITY genetic advance principal component analysis hierarchical clustering LINSEED
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Agro-Morphological, Physico-Chemical and Molecular Characterization of Rice Germplasm with Similar Names of Bangladesh
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作者 Mir Sharf Uddin AHMED Mohammad KHALEQUZZAMAN +1 位作者 Md.Khairul BASHAR Abul Kalam Mohammad SHAMSUDDIN 《Rice science》 SCIE CSCD 2016年第4期211-218,共8页
Thirty-one duplicate and similar named rice germplasms of Bangladesh were studied to assess the genetic variation for the agro-morphological and physico-chemical traits and simple sequence repeat banding patterns duri... Thirty-one duplicate and similar named rice germplasms of Bangladesh were studied to assess the genetic variation for the agro-morphological and physico-chemical traits and simple sequence repeat banding patterns during 2009–2012 at Bangladesh Rice Research Institute. The range of variations within the cultivar groups showed higher degree. The principal component analysis showed that the first five components with vector values > 1 contributed 82.90% of the total variations. The cluster analysis grouped the genotypes into four clusters, where no duplicate germplasm was found. The highest number(11) of genotypes was constellated in cluster I and the lowest(3) in cluster II. The intra- and inter-cluster distances were the maximum in cluster I(0.93) and between clusters I and IV(24.61), respectively, and the minimum in cluster IV(0.62) and between clusters I and III(5.07), respectively. The cluster mean revealed that the crosses between the genotypes of cluster I with those of clusters II and IV would exhibit high heterosis for maximum good characters. A total of 350 alleles varied from 3(RM277) to 14(RM21) with an average of 7.8 per locus were detected at 45 microsatellite loci across the 31 rice accessions. The gene diversity ranged from 0.48 to 0.90 with an average of 0.77, and the polymorphism information content values from 0.44(RM133) to 0.89(RM206) with an average of 0.74. RM206, RM21, RM55, RM258 and RM433 were considered as the best markers on the basis of their higher polymorphism information content values. The dendrogram from unweighted pair-group method with arithmetic average clustering also classified the genotypes into four groups, where group IV comprised of 20 genotypes and group III of one genotype, but no duplicate was found. Finally, similar and duplicate named rice germplasms need to be conserved in gene bank as are distinct from each other. 展开更多
关键词 diversity simple sequence repeat similar name LANDRACE rice agro-morphological and PHYSICO-CHEMICAL TRAIT
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Agro-morphological Characteristics and Sensory Evaluation of Native Peruvian Chili Peppers
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作者 Kirti Patel Rosa Calderon +3 位作者 Edgard Asencios Dioliza Vilchez Mavel Marcelo Rosario Rojas 《Journal of Agricultural Science and Technology(B)》 2016年第3期180-187,共8页
In this work, 31 native Peruvian chili peppers were evaluated for their agro-morphological characteristics and sensory attributes. The descriptive sensory analysis (DSA) was used to evaluate the 31 chili pepper samp... In this work, 31 native Peruvian chili peppers were evaluated for their agro-morphological characteristics and sensory attributes. The descriptive sensory analysis (DSA) was used to evaluate the 31 chili pepper samples based on their acid, bell pepper, sweet, tomato, apple, citrus, fruity, herbal, oregano and passion fruit attributes. The data obtained from the DSA enabled the grouping of these 31 chili peppers into six groups based on their different sensory attributes, such as fruity, bell pepper and herbal. The most abundant group (12 of the 31) had the bell pepper, apple, herbal, fruity and sweet attributes. Each group contained different species and different physical appearances, indicating that species or different forms of chili pepper do not define that sensory attribute. Considering the fact that Peruvian peppers are in high demand, the results achieved would be useful for growers, producers and chefs, as well as for further breeding activities. 展开更多
关键词 Chili peppers Peru sensory analysis agro-morphological characteristics.
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Preliminary Assessment of Genetic Diversity in Three Taro (Colocasia esculenta L, Schott) Landraces Using Agro-morphological and SSR DNA Characterisation
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作者 Tafadzwanashe Mabhaudhi Albert Thembinkosi Modi 《Journal of Agricultural Science and Technology(B)》 2013年第4期265-271,共7页
Taro (Colocasia esculenta L. Schott) is an important underutilised crop in South Africa, East Africa and Indonesia. Three taro landraces, namely, Dumbe Lomfula (wild), KwaNgwanase and Umbumbulu, were collected fro... Taro (Colocasia esculenta L. Schott) is an important underutilised crop in South Africa, East Africa and Indonesia. Three taro landraces, namely, Dumbe Lomfula (wild), KwaNgwanase and Umbumbulu, were collected from two locations in KwaZulu-Natal (KZN), South Africa, and planted at two locations, Pietermaritzburg (KZN) and Roodeplaat, Pretoria. Ago-morphological characterisation of vegetative and corm characteristics were done four months after planting and at harvest, respectively. Sampling for DNA fingerprinting using five SSR primers was done using leaf material four months after planting. Agro-morphological characterisation was useful in showing differences between the wild landrace and the two cultivated landraces, as well as identification of dasheen and eddoe types. SSR primer characterisation showed that despite significant morphological difference, the wild Dumbe Lomfula and Umbumbulu landraces were closely related but different from the KwaNgwanase landrace. Although landraces showed great morphological variation, this did not necessarily imply genetic variation. It is concluded that SSR primers are more useful for characterising taro landraces. 展开更多
关键词 agro-morphology characterisation DNA LANDRACES SSR primers taro (Colocasia esculenta L. Schott) geneticdiversity.
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Responses of Annual Variability of Vegetation NPP to Climate Variables Using Satellite Techniques in Gadarif State, Sudan
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作者 Anwar Mohamedelhassan Bo Zhang +1 位作者 Abdelrahim E. Jahelnabi Eman M. Elhassan 《Journal of Geographic Information System》 2024年第2期136-147,共12页
Plants play an essential role in matter and energy transformations and are key messengers in the carbon and energy cycle. Net primary productivity (NPP) reflects the capability of plants to transform solar energy into... Plants play an essential role in matter and energy transformations and are key messengers in the carbon and energy cycle. Net primary productivity (NPP) reflects the capability of plants to transform solar energy into photosynthesis. It is very sensible for factors affecting on vegetation variability such as climate, soils, plant characteristics and human activities. So, it can be used as an indicator of actual and potential trend of vegetation. In this study we used the actual NPP which was derived from MODIS to assess the response of NPP to climate variables in Gadarif State, from 2000 to 2010. The correlations between NPP and climate variables (temperature and precipitation) are calculated using Pearson’s Correlation Coefficient and ordinary least squares regression. The main results show the following 1) the correlation Coefficient between NPP and mean annual temperature is Somewhat negative for Feshaga, Rahd, Gadarif and Galabat areas and weakly negative in Faw area;2) the correlation Coefficient between NPP and annual total precipitation is weakly negative in Faw, Rahd and Galabat areas and somewhat negative in Galabat and Rahd areas. This study demonstrated that the correlation analysis between NPP and climate variables (precipitation and temperature) gives reliably result of NPP responses to climate variables that is clearly in a very large scale of study area. 展开更多
关键词 Climate Variables MODIS NPP Climate Change Correlation Coefficient Gadarif State Remote Sensing GIS Applications
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Genetic Diversity of Local Rice Accessions Cultivated in Guinea Based on Agro-Morphological Traits and Identification of Sources of Tolerance to Iron Toxicity
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作者 Mamadou Laho Barry Nerbéwendé Sawadogo +5 位作者 Mahamadi Hamed Ouédraogo Kiswendsida Romaric Nanema Sawa Camara Moussa Sié Pauline Bationo-Kando Mahamadou Sawadogo 《Agricultural Sciences》 2021年第10期1070-1088,共19页
In Guinea, traditional rice varieties are the most widely cultivated in rural areas despite their low yield and high susceptibility to iron toxicity. Moreover, the introduction of new improved varieties tolerant to ir... In Guinea, traditional rice varieties are the most widely cultivated in rural areas despite their low yield and high susceptibility to iron toxicity. Moreover, the introduction of new improved varieties tolerant to iron toxicity poses a serious threat to the preservation of the genetic resources of these traditional varieties, whose genetic diversity remains poorly known. The present study therefore aims at a better valorisation of these local rice cultivars through the evaluation of their agromorphological diversity and the identification of genotypes potentially tolerant or resistant to iron toxicity. Thus, 90 accessions collected in the regions of Kindia and Macenta and six controls susceptible or resistant to iron toxicity (AZUCENA, BOUAKE 189, CK 73, IR64, NERICAL 19 and AURYLUX 6) were evaluated in three replicate alpha lattice designs in two sites (Sérédou and Kilissi) using 16 agromorphological traits. The results showed significant agromorphological variability of the traditional accessions at both sites for all qualitative and most quantitative traits studied. In addition, 30 local cultivars expressed similar or higher grain yields than the resistant or tolerant controls at both sites, of which 12 were found to be stable at both sites. Of the 12 cultivars identified, five were resistant and seven tolerant to iron toxicity. These 12 accessions could be used in the varietal improvement of lowland rice in Guinea Conakry. 展开更多
关键词 Local Varieties ORYZA Genetic variability Environmental Stress GUINEA
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Genetic Diversity Assessment of Moroccan Sesame(Sesamum indicum L.)Populations Using Agro-morphological Traits
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作者 Meriem El Harfi Marouane Jbilou +3 位作者 Hafida Hanine Hajar Rizki Mohamed Fechtali Abdelghani Nabloussi 《Journal of Agricultural Science and Technology(A)》 2018年第5期296-305,共10页
Genetic diversity of Moroccan sesame(Sesamum indicum L.)was analyzed for the first time using agro-morphological traits.Thirty-three sesame populations collected from Tadla region in Morocco were evaluated for 13 para... Genetic diversity of Moroccan sesame(Sesamum indicum L.)was analyzed for the first time using agro-morphological traits.Thirty-three sesame populations collected from Tadla region in Morocco were evaluated for 13 parameters in three contrasted environments,Afr-13,Afr-14 and Atj-14.Broad and significant variation among populations was observed only for three agro-morphologic traits,namely first capsule height(FCH),number of seeds per capsule(NSC)and thousand seeds weight(TSW).The respective overall averages were 71.82 cm(ranging from 65 cm to 77 cm),61.39(varying from 57 to 65)and 3.20 g(ranging from 3.0 g to 3.4 g).Environment had a highly significant effect on all studied parameters,except capsule size and oil content.The obtained mean values of parameters studied showed that environment Afr-14 was the most favorable for most of them,particularly seed yield(1.32 t/ha)and TSW(3.57 g).Significant and interesting correlations were observed between seed yield per plant(SYP)and other parameters.As relevant implication of this finding,number of capsules per plant(NCP)and NSC could be used as valuable selection criteria in sesame breeding program.However,limited and non-significant variation among sesame populations for most of parameters studied suggests that they are genetically very close and may be derived from a single cultivar or germplasm.Molecular characterization is needed to confirm or refute this hypothesis.Besides,when compared with sesame grown throughout the world,Moroccan sesame was found to be very promising,which open up the possibility to develop this crop in this country. 展开更多
关键词 Sesame(Sesamum indicum L.) Morocco Tadla REGION variability environment
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