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Utilizing On-the-Go Soil Sensors to Explore Correlations between Electrical Conductivity, Soil Reflectance, Slope, and Elevation of Mississippi Farm Soils 被引量:1
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作者 Reginald S. Fletcher 《Agricultural Sciences》 2025年第1期112-122,共11页
Ten physical and environmental variables collected from an on-the-go soil sensor at two field sites (MF3E and MF11S) in Mississippi, USA, were analyzed to assess soil variability and the interrelationships among the m... Ten physical and environmental variables collected from an on-the-go soil sensor at two field sites (MF3E and MF11S) in Mississippi, USA, were analyzed to assess soil variability and the interrelationships among the measurements. At MF3E, moderate variability was observed in apparent electrical conductivity shallow (ECas), slope, and ECa ratio measurements, with coefficients of variation ranging from 20% to 27%. In contrast, MF11S exhibited higher variability, particularly in ECas and ECad (deep) measurements, which exceeded 30% in their coefficient of variation values, indicating significant differences in soil composition and moisture content. Correlation analysis revealed strong positive relationships between the near-infrared-to-red ratio and red reflectance (r = 0.897***) soil values at MF3E. MF11S demonstrated a strong negative correlation between ECas and ECad readings with the x-coordinate (r ***). Scatter plots and fitted models illustrated the complexity of relationships, with many showing nonlinear trends. These findings emphasize the need for continuous monitoring and advanced modeling to understand the dynamic nature of soil properties and their implications for agricultural practices. Future research should explore the underlying mechanisms driving variability in the soil characteristics to enhance soil management strategies at the study sites. 展开更多
关键词 Mobile Soil Sensors NEAR-INFRARED Correlation Nonlinear
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Advancing the Indian cattle pangenome: characterizing non-reference sequences in Bos indicus 被引量:1
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作者 Sarwar Azam Abhisek Sahu +6 位作者 Naveen Kumar Pandey Mahesh Neupane Curtis P Van Tassell Benjamin D Rosen Ravi Kumar Gandham Subha Narayan Rath Subeer S Majumdar 《Journal of Animal Science and Biotechnology》 2025年第2期497-516,共20页
Background India harbors the world’s largest cattle population,encompassing over 50 distinct Bos indicus breeds.This rich genetic diversity underscores the inadequacy of a single reference genome to fully capture the... Background India harbors the world’s largest cattle population,encompassing over 50 distinct Bos indicus breeds.This rich genetic diversity underscores the inadequacy of a single reference genome to fully capture the genomic landscape of Indian cattle.To comprehensively characterize the genomic variation within Bos indicus and,specifically,dairy breeds,we aim to identify non-reference sequences and construct a comprehensive pangenome.Results Five representative genomes of prominent dairy breeds,including Gir,Kankrej,Tharparkar,Sahiwal,and Red Sindhi,were sequenced using 10X Genomics‘linked-read’technology.Assemblies generated from these linked-reads ranged from 2.70 Gb to 2.77 Gb,comparable to the Bos indicus Brahman reference genome.A pangenome of Bos indicus cattle was constructed by comparing the newly assembled genomes with the reference using alignment and graph-based methods,revealing 8 Mb and 17.7 Mb of novel sequence respectively.A confident set of 6,844 Non-reference Unique Insertions(NUIs)spanning 7.57 Mb was identified through both methods,representing the pange-nome of Indian Bos indicus breeds.Comparative analysis with previously published pangenomes unveiled 2.8 Mb(37%)commonality with the Chinese indicine pangenome and only 1%commonality with the Bos taurus pange-nome.Among these,2,312 NUIs encompassing~2 Mb,were commonly found in 98 samples of the 5 breeds and des-ignated as Bos indicus Common Insertions(BICIs)in the population.Furthermore,926 BICIs were identified within 682 protein-coding genes,54 long non-coding RNAs(lncRNA),and 18 pseudogenes.These protein-coding genes were enriched for functions such as chemical synaptic transmission,cell junction organization,cell-cell adhesion,and cell morphogenesis.The protein-coding genes were found in various prominent quantitative trait locus(QTL)regions,suggesting potential roles of BICIs in traits related to milk production,reproduction,exterior,health,meat,and carcass.Notably,63.21%of the bases within the BICIs call set contained interspersed repeats,predominantly Long Inter-spersed Nuclear Elements(LINEs).Additionally,70.28%of BICIs are shared with other domesticated and wild species,highlighting their evolutionary significance.Conclusions This is the first report unveiling a robust set of NUIs defining the pangenome of Bos indicus breeds of India.The analyses contribute valuable insights into the genomic landscape of desi cattle breeds. 展开更多
关键词 BICIs Bos indicus CATTLE Genome assembly Linked-reads NUIs Pangenome
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Identification and characterization of Sr59-mediated stem rust resistance in a novel wheat-rye translocation T2BL 2BS-2RL 被引量:1
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作者 Mahboobeh Yazdani Matthew N.Rouse +5 位作者 Prabin Bajgain Tatiana V.Danilova Ivan Motsnyi Brian J.Steffenson Mehran Patpour Mahbubjon Rahmatov 《The Crop Journal》 2025年第3期909-918,共10页
Emerging new races of wheat stem rust(Puccinia graminis f.sp.tritici)are threatening global wheat(Triticum aestivum L.)production.Host resistance is the most effective and environmentally friendly method of controllin... Emerging new races of wheat stem rust(Puccinia graminis f.sp.tritici)are threatening global wheat(Triticum aestivum L.)production.Host resistance is the most effective and environmentally friendly method of controlling stem rust.The stem rust resistance gene Sr59 was previously identified within a T2DS 2RL wheat-rye whole arm translocation,providing broad-spectrum resistance to various stem rust races.Seedling evaluation,molecular marker analysis,and cytogenetic studies identified wheat-rye introgression line#284 containing a new translocation chromosome T2BL 2BS-2RL.This line has demonstrated broad-spectrum resistance to stem rust at the seedling stage.Seedling evaluation and cytogenetic analysis of three backcross populations between the line#284 and the adapted cultivars SLU-Elite,Navruz,and Linkert confirmed that Sr59 is located within the short distal 2RL translocation.This study aimed physical mapping of Sr59 in the 2RL introgression segment and develop a robust molecular marker for marker-assisted selection.Using genotyping-by-sequencing(GBS),GBS-derived SNPs were aligned with full-length annotated rye nucleotide-binding leucine-rich repeat(NLR)genes in the parental lines CS ph1b,SLU238,SLU-Elite,Navruz,and Linkert,as well as in 33 BC4F5progeny.Four NLR genes were identified on the 2R chromosome,with Chr2R_NLR_60 being tightly linked to the Sr59resistance gene.In-silico functional enrichment analysis of the translocated 2RL region(25,681,915 bp)identified 223 genes,with seven candidate genes associated with plant disease resistance and three linked to agronomic performance,contributing to oxidative stress response,protein kinase activity,and cellular homeostasis.These findings facilitate a better understanding of the genetic basis of stem rust resistance provided by Sr59. 展开更多
关键词 Cytogenetic analysis Marker-assisted selection NLR Resistance gene Wheat-rye introgression
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Agricultural and environmental significance of soil organic matter and plant biomass:Insight from ultrahigh-resolution Fourier transform ion cyclotron resonance mass spectrometry
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作者 Zhongqi HE 《Pedosphere》 2025年第1期3-7,共5页
Ultrahigh-resolution Fourier transform ion cyclotron resonance mass spectrometry(FT-ICR MS)is an advanced instrument capable of separating and determining molecular mass-to-charge ratios with sub-ppm level accuracy.A ... Ultrahigh-resolution Fourier transform ion cyclotron resonance mass spectrometry(FT-ICR MS)is an advanced instrument capable of separating and determining molecular mass-to-charge ratios with sub-ppm level accuracy.A typical FT-ICR MS spectrogram can identify hundreds to thousands of formulas in a complex sample.This perspective briefly examines the application of FT-ICR MS to soil organic matter and plant biomass studies,highlighting their significant contributions to sustainable agriculture and environment. 展开更多
关键词 soil mass resonance
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Advancements in remote sensing techniques for earthquake engineering:A review
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作者 Chinmayi H.K K.Colton Flynn Amanda J.Ashworth 《Earthquake Research Advances》 2025年第3期110-122,共13页
Remote sensing technologies play a vital role in our understanding of earthquakes and their impact on the Earth's surface.These technologies,including satellite imagery,aerial surveys,and advanced sensors,contribu... Remote sensing technologies play a vital role in our understanding of earthquakes and their impact on the Earth's surface.These technologies,including satellite imagery,aerial surveys,and advanced sensors,contribute significantly to our understanding of the complex nature of earthquakes.This review highlights the advancements in the integration of remote sensing technologies into earthquake studies.The combined use of satellite imagery and aerial photography in conjunction with geographic information systems(GIS)has been instrumental in showcasing the significance of fusing various types of satеllitеdata sourcеs for comprеhеnsivееarthquakеdamagеassеssmеnts.However,remote sensing encounters challenges due to limited pre-event imagery and restricted postearthquake site access.Furthеrmorе,thеapplication of dееp-lеarning mеthods in assеssingеarthquakе-damagеd buildings dеmonstratеs potеntial for furthеr progrеss in this fiеld.Overall,the utilization of remote sensing technologies has greatly enhanced our comprehension of earthquakes and their effects on the Earth's surface.The fusion of remote sensing technology with advanced data analysis methods holds tremendous potential for driving progress in earthquake studies and damage assessment. 展开更多
关键词 Remote sensing Earthquake engineering Satellite imagery Machine learning dееp-lеarning mеthods
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Contribution of reforestation to soil aggregate stability and shear strength in hilly red soil region of southern China
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作者 ZHU Jinqi ZHANG Na +3 位作者 JIANG Yihui WANG Dan Glenn WILSON ZHENG Bofu 《Journal of Mountain Science》 2025年第7期2497-2511,共15页
In response to the effectiveness of reforestation in controlling soil erosion,there has been a dramatic increase in forest coverage in the hilly red soil region of southern China.Aggregate stability and soil shear str... In response to the effectiveness of reforestation in controlling soil erosion,there has been a dramatic increase in forest coverage in the hilly red soil region of southern China.Aggregate stability and soil shear strength are indicators that reflect soil resistance to erosion and its ability to prevent shallow landslides,respectively.However,limited research has focused on the response of soil aggregate stability and shear strength to reforestation.We selected three types of reforestations(Phyllostachys edulis forest,Cunninghamia lanceolata(Lamb.)Hook.forest,Citrus sinensis(L.)Osbeck.orchard),a natural forest(mixed coniferous and broadleaf forests),and a fallow land as study plots,and measured root traits,and soil physicochemical traits,i.e.,pH,soil organic matter(SOC),Soil water content(SWC),soil bulk density(BD),soil cohesion(c),soil internal friction angle(φ)and analyzed their multiple interactions.The soil aggregate stability traits,refer to the mean weight diameter(MWD)and geometric mean diameter(GMD),exhibited a significant increase in reforested plots,approximately 200%compared to fallow land and 50%compared to natural forests.For soil shear strength the values were approximately 20%higher than in fallow land and approximately 10%lower than in natural forests.Soil aggregate stability and soil shear strength did not exhibit a significant positive correlation across all plots,and the underlying drivers of these traits were variable.For instance,in natural forest and timber stands,soil aggregate stability was mainly influenced by soil organic carbon,while soil shear strength was primarily affected by root length density.In economic forest,aggregate stability and shear strength are mainly affected by organic carbon.Overall,we found that vegetation restoration enhances soil erosion resistance,however,the primary drivers for the improvement of aggregate stability(soil organic carbon)and shear strength(root length density)are different.Therefore,in future benefit assessments of vegetation restoration projects aimed at soil erosion control,different indicators should be considered based on specific conditions. 展开更多
关键词 Vegetation reforestation Soil aggregate stability Soil shear strength Root length density
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Genomic insights into oxalate content in spinach:A genome-wide association study and genomic prediction approach
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作者 Haizheng Xiong Kenani Chiwina +6 位作者 Waltram Ravelombola Yilin Chen Ibtisam Alatawi Qun Luo Theresa Makawa Phiri Beiquan Mou Ainong Shi 《Horticultural Plant Journal》 2025年第3期1140-1151,共12页
Oxalate content in spinach is a key trait of interest due to its relevance to human health.Understanding the genetic basis of it can facilitate the development of spinach varieties with reduced oxalate levels.In pursu... Oxalate content in spinach is a key trait of interest due to its relevance to human health.Understanding the genetic basis of it can facilitate the development of spinach varieties with reduced oxalate levels.In pursuit of understanding the genetic determinants,a diverse panel comprising 288 spinach accessions underwent thorough phenotyping of oxalate content and were subjected to whole-genome resequencing,resulting in a comprehensive dataset encompassing 14386 single-nucleotide polymorphisms(SNPs).Leveraging this dataset,we conducted a genome-wide association study(GWAS)to identify noteworthy SNPs associated with oxalate content.Furthermore,we employed genomic prediction(GP)via cross-prediction,utilizing five GP models,to assess genomic estimated breeding values(GEBVs)for oxalate content.The observed normal distribution and the wide range of oxalate content,exceeding 600.0 mg$100 g^(-1),underscore the complex and quantitative nature of this trait,likely influenced by multiple genes.Additionally,our analysis revealed distinct stratification,delineating the population into four discernible subpopulations.Furthermore,GWAS analysis employing five models in GAPIT 3 and TASSEL 5 unveiled nine significant SNPs(four SNPs on chromosome 1 and five on chromosome 5)associated with oxalate content.These loci exhibited associations with six candidate genes,which might have potential contribution to oxalate content regulation.Remarkably,our GP models exhibited notable predictive abilities,yielding average accuracies of up to 0.51 for GEBV estimation.The integration of GWAS and GP approaches offers a holistic comprehension of the genetic underpinnings of oxalate content in spinach.These findings offered a promising avenue for the development of spinach cultivars and hybrids optimized for oxalate levels,promoting consumer health. 展开更多
关键词 GWAS Spinach breeding OXALATE Genomic prediction
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Modeling and Estimating Soybean Leaf Area Index and Biomass Using Machine Learning Based on Unmanned Aerial Vehicle-Captured Multispectral Images
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作者 Sadia Alam Shammi Yanbo Huang +5 位作者 Weiwei Xie Gary Feng Haile Tewolde Xin Zhang Johnie Jenkins Mark Shankle 《Phyton-International Journal of Experimental Botany》 2025年第9期2745-2766,共22页
Crop leaf area index(LAI)and biomass are two major biophysical parameters to measure crop growth and health condition.Measuring LAI and biomass in field experiments is a destructive method.Therefore,we focused on the ... Crop leaf area index(LAI)and biomass are two major biophysical parameters to measure crop growth and health condition.Measuring LAI and biomass in field experiments is a destructive method.Therefore,we focused on the application of unmanned aerial vehicles(UAVs)in agriculture,which is a cost and labor-efficientmethod.Hence,UAV-captured multispectral images were applied to monitor crop growth,identify plant bio-physical conditions,and so on.In this study,we monitored soybean crops using UAV and field experiments.This experiment was conducted at theMAFES(Mississippi Agricultural and Forestry Experiment Station)Pontotoc Ridge-Flatwoods Branch Experiment Station.It followed a randomized block design with five cover crops:Cereal Rye,Vetch,Wheat,MC:mixed Mustard and Cereal Rye,and native vegetation.Planting was made in the fall,and three fertilizer treatments were applied:Synthetic Fertilizer,Poultry Litter,and none,applied before planting the soybean,in a full factorial combination.We monitored soybean reproductive phases at R3(initial pod development),R5(initial seed development),R6(full seed development),and R7(initial maturity)and used UAV multispectral remote sensing for soybean LAI and biomass estimations.The major goal of this study was to assess LAI and biomass estimations from UAV multispectral images in the reproductive stages when the development of leaves and biomass was stabilized.Wemade about fourteen vegetation indices(VIs)fromUAVmultispectral images at these stages to estimate LAI and biomass.Wemodeled LAI and biomass based on these remotely sensed VIs and ground-truth measurements usingmachine learning methods,including linear regression,Random Forest(RF),and support vector regression(SVR).Thereafter,the models were applied to estimate LAI and biomass.According to the model results,LAI was better estimated at the R6 stage and biomass at the R3 stage.Compared to the other models,the RF models showed better estimation,i.e.,an R^(2) of about 0.58–0.68 with an RMSE(rootmean square error)of 0.52–0.60(m^(2)/m^(2))for the LAI and about 0.44–0.64 for R^(2) and 21–26(g dry weight/5 plants)for RMSE of biomass estimation.We performed a leave-one-out cross-validation.Based on cross-validatedmodels with field experiments,we also found that the R6 stage was the best for estimating LAI,and the R3 stage for estimating crop biomass.The cross-validated RF model showed the estimation ability with an R^(2) about 0.25–0.44 and RMSE of 0.65–0.85(m^(2)/m^(2))for LAI estimation;and R^(2) about 0.1–0.31 and an RMSE of about 28–35(g dry weight/5 plants)for crop biomass estimation.This result will be helpful to promote the use of non-destructive remote sensing methods to determine the crop LAI and biomass status,which may bring more efficient crop production and management. 展开更多
关键词 SOYBEAN LAI BIOMASS reproductive growth stage UAV multispectral imaging machine learning
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Assessing fiber quality variability among modern upland cotton cultivars and incorporating it into the GOSSYM-based fiber quality simulation model
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作者 BEEGUM Sahila HASSAN Muhammad Adeel +2 位作者 REDDY Krishna N. REDDY Vangimalla REDDY Kambham Raja 《Journal of Cotton Research》 2025年第2期213-227,共15页
Background GOSSYM is a mechanistic,process-based cotton model that can simulate cotton crop growth and development,yield,and fiber quality.Its fiber quality module was developed based on controlled experiments explici... Background GOSSYM is a mechanistic,process-based cotton model that can simulate cotton crop growth and development,yield,and fiber quality.Its fiber quality module was developed based on controlled experiments explicitly conducted on the Texas Marker^(-1)(TM1)variety,potentially making its functional equations more aligned with this cultivar.To assess the model’s broader applicability,this study analyzed fiber quality data from 40 upland cotton cultivars,including TM1.The measured fiber quality from all cultivars was then compared with the modelsimulated fiber quality.Results Among the 40 upland cultivars,fiber strength varied from 28.4 cN·tex^(-1) to 34.6 cN·tex^(-1),fiber length ranged from 27.1 mm to 33.3 mm,micronaire value ranged from 2.7 to 4.6,and length uniformity index varied from 82.3%to 85.5%.The model simulated fiber quality closely matched the measured values for TM1,with the absolute percentage error(APE)being less than 0.92%for fiber strength,fiber length,and length uniformity index and 4.7%for micronaire.However,significant differences were observed for the other cultivars.The Pearson correlation coefficient(r)between the measured and simulated values was negative for all fiber quality traits,and Wilmotts’s index of agreement(WIA)was below 0.45,indicating a strong model bias toward TM1 without incorporating cultivar-specific parameters.After incorporating cultivar-specific parameters,the model’s performance improved significantly,with an average r-value of 0.84 and WIA of 0.88.Conclusions The adopted methodology and estimated cultivar-specific parameters improved the model’s simulation accuracy.This approach can be applied to newer cotton cultivars,enhancing the GOSSYM model’s utility and its applicability for agricultural management and policy decisions. 展开更多
关键词 COTTON GOSSYM Crop modeling Fiber quality Cultivar-specific parameter
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Sugarcane genetics:Underlying theory and practical application
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作者 Hengbo Wang Yong-Bao Pan +4 位作者 Mingxing Wu Junhong Liu Shiwei Yang Qibin Wu Youxiong Que 《The Crop Journal》 2025年第2期328-338,共11页
Sugarcane is recognized as the fifth largest crop globally,supplying 80%of sugar and 40%of bioenergy production.However,sugarcane genetic research has significantly lagged behind other crops due to its complex genetic... Sugarcane is recognized as the fifth largest crop globally,supplying 80%of sugar and 40%of bioenergy production.However,sugarcane genetic research has significantly lagged behind other crops due to its complex genetic background,high ploidy(8-13×),aneuploidy,limited flowering,and a long growth cycle(more than one year).Cross breeding began in 1887 following the discovery that sugarcane seeds could germinate.Both self-and cross-pollination and selection were conducted by sugarcane breeders,but new cultivars were often eliminated due to disease susceptibility.Within the Saccharum genus,different species possess variable numbers of chromosomes.Wild sugarcane species intercrossed with each other,leading to development of the‘Nobilization’breeding strategy,which significantly improved yield,sucrose,fiber content,and disease resistance,and accelerated genetic improvement of cultivars.In recent years,scientific achievements have also been made in sugarcane genome sequencing,molecular marker development,genetic linkage map construction,localization of quantitative trait locus(QTL),and trait-associated gene identification.This review focuses on the progress in sugarcane genetic research,analyzes the technical difficulties faced,presents opportunities and challenges,and provides guidance and references for future sugarcane genetics research and cultivar breeding.Finally,it offers directions for future on sugarcane genetics. 展开更多
关键词 Interspecific hybridization Nobilization breeding Non-Mendelian inheritance Sugarcane breeding
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High-throughput phenotyping discovers new stable loci controlling senescence rate in bread wheat
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作者 Lei Li Jindong Liu +10 位作者 Muhammad Adeel Hassan Duoxia Wang Keyi Wang Shuaipeng Fei Jianqi Zeng Awais Rasheed Xianchun Xia Zhonghu He Yong He Yong Zhang Yonggui Xiao 《The Crop Journal》 2025年第4期1168-1177,共10页
Non-destructive time-series assessment of chlorophyll content in flag-leaf(FLC)accurately mimics the senescence rate and the identification of genetic loci associated with senescence provides valuable knowledge to imp... Non-destructive time-series assessment of chlorophyll content in flag-leaf(FLC)accurately mimics the senescence rate and the identification of genetic loci associated with senescence provides valuable knowledge to improve yield stability under stressed environments.In this study,we employed both unmanned aerial vehicles(UAVs)equipped with red–green–blue(RGB)camera and ground-based SPAD-502 instrument to conduct temporal phenotyping of senescence.A total of 262 recombinant inbred lines derived from the cross of Zhongmai 578/Jimai 22 were evaluated for senescence-related traits across three environments,spanning from heading to 35 d post-anthesis.The manual senescence rate(MSR)was quantified using the FLC and the active accumulated temperature,and UAV derived vegetation index were utilized to assess the stay-green rate(USG)facilitating the identification of senescent and stay-green lines.Results indicated that higher senescence rates significantly impacted grain yield,primarily by influencing thousand-kernel weight,and plant height.Quantitative trait loci(QTL)mapping for FLC,USG,and MSR using the 50K SNP array identified 38 stable loci associated with RGB-based vegetation indices and senescence-related traits:among which 19 loci related to senescence traits from UAV and FLC were consistently detected across at least two growth stages,with nine loci likely representing novel QTL.This study highlights the potential of UAV-based high-throughput phenotyping and phenology in identifying critical loci associated with senescence rates in wheat,validating the relationship between senescence rates and yield-related traits in wheat,offering valuable opportunities for gene discovery and significant applications in breeding programs. 展开更多
关键词 Aerial digital imaging Active accumulated temperature CHLOROPHYLL QTL Senescence rate Common wheat
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水稻核心种质表型性状遗传多样性分析及综合评价 被引量:191
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作者 胡标林 万勇 +4 位作者 李霞 雷建国 罗向东 严文贵 谢建坤 《作物学报》 CAS CSCD 北大核心 2012年第5期829-839,共11页
种质资源是水稻遗传育种和解析复杂性状的重要基础,而对遗传多样评估有利于鉴定最优亲本组合,以产生遗传变异最大的后代群体和促进不同资源的有利基因渗透到栽培品种。选用14个表型性状对美国农业部水稻核心种质中的六大洲1579份水稻种... 种质资源是水稻遗传育种和解析复杂性状的重要基础,而对遗传多样评估有利于鉴定最优亲本组合,以产生遗传变异最大的后代群体和促进不同资源的有利基因渗透到栽培品种。选用14个表型性状对美国农业部水稻核心种质中的六大洲1579份水稻种质,分析与评价其遗传多样性和优良稻种资源,主要结果如下:(1)亚洲、非洲与大洋洲种质间遗传距离较远,且亚洲、非洲和大洋洲的水稻资源具有较丰富的表型遗传多样性,而不同性状的遗传多样性在洲际间表现不同;粒长宽比、碱消值、株高、粒宽、千粒重和淀粉含量6个性状具有很高的表型遗传多样性。(2)采用主成分分析法和逐步回归分析法综合评判表明,越南的PI392768的综合性状表现最好,法国的PI281760综合性状表现最差,同时淀粉含量、抽穗期、株高、倒伏性、糙米色和颖壳色6个性状可作为种质资源综合评价指标。在水稻育种中应注重利用具有丰富遗传多样性的种质资源,并在亲本选配时适当选择遗传距离较远且综合性状表现差异大的种质材料。 展开更多
关键词 核心种质 表型性状 遗传多样性 主成分分析 综合评价
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集成GPS和GIS技术的变量灌溉控制系统(英文) 被引量:17
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作者 杨青 庞树杰 +3 位作者 杨成海 李敏通 李勇军 杨术明 《农业工程学报》 EI CAS CSCD 北大核心 2006年第10期134-138,共5页
结合中国现实国情,应用先进的单片机、G IS、GPS以及变量控制技术,设计了一种经济实用、先进的变量灌溉控制系统。系统设计采用AT 89C 51单片机作为系统微处理器,Jup iter GPS OEM二次开发作为GPS接收机,IC卡作为G IS数据传递媒体,并根... 结合中国现实国情,应用先进的单片机、G IS、GPS以及变量控制技术,设计了一种经济实用、先进的变量灌溉控制系统。系统设计采用AT 89C 51单片机作为系统微处理器,Jup iter GPS OEM二次开发作为GPS接收机,IC卡作为G IS数据传递媒体,并根据矢量法提出一种简单快速的田间定位和数据查询算法。灌溉机在田间工作时,系统可从GPS OEM得到位置信息,进行地块识别和位置判断;然后根据位置信息从IC卡的G IS信息中查询土壤属性数据或处方数据,结合机械行走速度、施水幅宽等进行运算,得出某一时刻的灌水量;最后向控制器发出指令,实现变量节水灌溉。田间和实验室模拟试验结果表明,自行研制的低成本GPS OEM接收机,可获得与A g GPS132相当的定位精度,控制系统能根据处方图的不同需水量,通过电磁阀驱动电路得到变化的输出,实现自动变量施水,系统也能根据需水量进行手动灌溉。 展开更多
关键词 变量灌溉 控制系统 处方图 GPS OEM GIS
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喜旱莲子草茎叶解剖结构从原产地到入侵地的变异式样 被引量:22
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作者 潘晓云 梁汉钊 +3 位作者 Alejandro Sosa 耿宇鹏 李博 陈家宽 《生物多样性》 CAS CSCD 北大核心 2006年第3期232-240,共9页
长期以来人们一直认为,外来种入侵及其危害是由于一个物种从原产地到入侵地其环境因子改变(如天敌压力的减弱等)而导致的。近年来,越来越多的研究者开始认识到,生物入侵过程实际上是一个现代人类活动影响下的物种的快速进化过程,生物入... 长期以来人们一直认为,外来种入侵及其危害是由于一个物种从原产地到入侵地其环境因子改变(如天敌压力的减弱等)而导致的。近年来,越来越多的研究者开始认识到,生物入侵过程实际上是一个现代人类活动影响下的物种的快速进化过程,生物入侵的进化遗传学已成为入侵生物学研究中最活跃的分支之一。作者比较了来自原产地(阿根廷)和入侵地(中国和美国)的喜旱莲子草(Alternantheraphiloxeroides)的11个种群在茎、叶解剖结构方面的变异式样,发现所研究的19个性状在原产地(阿根廷)和入侵地(中国和美国)的变异情况明显不同:在原产地种群中,共有9个性状指标存在显著差异,遗传率在49–89%之间,这9个性状是气孔密度、气孔指数、茎直径、髓腔直径、维管柱直径、皮层厚度、维管柱面积比、髓腔面积比和叶形指数;而在入侵地种群间,19个性状指标均无明显差异。这表明喜旱莲子草从原产地到入侵地其遗传多样性降低;入侵地喜旱莲子草种群间的形态变异主要为表型可塑性。根据19个形态指标对喜旱莲子草11个种群进行主成分分析和聚类,结果显示:所有入侵地种群和原产地的Ar1种群(SantaFé,59°49′W,29°16′S)聚为一类,原产地的Ar4(Tandil,59°03′W,37°11′S)单独聚为一类,原产地的其他4个种群聚为一类。表明Ar1种群可能与入侵中国的喜旱莲子草在基因型上更为接近。这一结果为进一步揭示喜旱莲子草入侵机理(如杂交适应性)和在原产地寻求对应天敌的生物防治工作提供了基础数据。 展开更多
关键词 生物入侵 形态变异 表型可塑性 Alternanthera philoxeroides
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中国大蒜种质资源遗传多样性和群体遗传结构分析 被引量:17
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作者 王海平 Philipp W.Simon +5 位作者 李锡香 程嘉琪 沈镝 宋江萍 邱杨 张晓辉 《中国农业科学》 CAS CSCD 北大核心 2012年第16期3318-3329,共12页
【目的】从分子水平了解中国大蒜种质资源的群体遗传结构和遗传背景。【方法】利用AFLP、SSR和InDel这3种分子标记对国家无性繁殖蔬菜资源圃保存的212份大蒜资源进行检测,通过Mega软件进行最大相似性聚类分析,Structure 2.1软件进行群... 【目的】从分子水平了解中国大蒜种质资源的群体遗传结构和遗传背景。【方法】利用AFLP、SSR和InDel这3种分子标记对国家无性繁殖蔬菜资源圃保存的212份大蒜资源进行检测,通过Mega软件进行最大相似性聚类分析,Structure 2.1软件进行群体遗传结构分析,SSPS软件进行分子标记与大蒜辣素含量和21个数量性状进行一元线性模型检测,考察两者之间的关联性及群体遗传结构的影响。【结果】3种分子标记在212份种质中扩增出502个位点,多态性位点为492个。群体遗传结构与聚类分析均将所有资源划分为5个群体,划分的类别基本一致。然而,群体遗传结构分析划分的5个群体,群内遗传信息多样性指数较小。对212份种质的22个数量性状与分子标记的线型模型分析表明,包括大蒜辣素含量在内的多个数量性状受群体遗传结构的影响较小。【结论】中国大蒜种质资源遗传背景丰富,群体遗传结构对数量性状的分布影响较小,适合进一步进行性状与分子标记之间关联分析研究。 展开更多
关键词 大蒜 关联分析 群体遗传结构 遗传多样性
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基于表型性状的中国大蒜资源遗传多样性分析 被引量:83
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作者 王海平 李锡香 +4 位作者 沈镝 邱杨 宋江萍 张晓辉 Philipp W.Simon 《植物遗传资源学报》 CAS CSCD 北大核心 2014年第1期24-31,共8页
对资源圃保存的212份大蒜种质资源的表型性状进行了系统鉴定,分析表明我国大蒜种质资源的表型变异丰富。主成分分析表明,29个性状可以归并为反映植株生长发育、产品特征和产量构成的8个主成分;进一步的聚类分析将所有资源分为特点明显的... 对资源圃保存的212份大蒜种质资源的表型性状进行了系统鉴定,分析表明我国大蒜种质资源的表型变异丰富。主成分分析表明,29个性状可以归并为反映植株生长发育、产品特征和产量构成的8个主成分;进一步的聚类分析将所有资源分为特点明显的2类5亚类。为了避免质量性状在种质评价中的主导作用,与产量相关的鳞茎数量性状的主成分分析显示,前3个主成分累积贡献率达74.83%,第一主成分中鳞茎重、鳞茎直径、鳞茎高和鳞芽数是影响产量的主要因子。主坐标排序将所有资源分为6类。通过综合评价,将大蒜鳞茎产量分为6个级别,筛选出单产大于15 t/hm2的资源3份。 展开更多
关键词 大蒜 遗传多样性 表型性状
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高光谱最优波长选择及Fisher判别分析法判别玉米颗粒表面黄曲霉毒素 被引量:24
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作者 褚璇 王伟 +3 位作者 张录达 郭浪花 Peggy Feldner Gerald Heitschmidt 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2014年第7期1811-1815,共5页
黄曲霉毒素是广泛存在于玉米中且具有剧毒的一种代谢产物,以美国农业部农业研究署(USDA-ARS) Toxicology and Mycotoxin Research Unit提供的2010年先锋玉米为研究对象,验证了高光谱成像技术对玉米中黄曲霉毒素检测的可行性。以甲... 黄曲霉毒素是广泛存在于玉米中且具有剧毒的一种代谢产物,以美国农业部农业研究署(USDA-ARS) Toxicology and Mycotoxin Research Unit提供的2010年先锋玉米为研究对象,验证了高光谱成像技术对玉米中黄曲霉毒素检测的可行性。以甲醇为溶剂制备四种不同浓度的黄曲霉毒素溶液,并将其逐一滴在等量的4组共120粒玉米颗粒表面,以未处理的30粒洁净玉米作为一组对照样本,将大小、形状相似的150个样品随机分为训练集103个,验证集47个;对获取的400~1000 nm波段范围内的高光谱图像,先进行标准正态变量变换(standard normal variate transformation ,SNV)预处理,然后引入基于 Fisher判别最小误判率的方法选择最优波长,并以所选波长作为Fisher判别分析法的输入建立判别模型,对玉米颗粒表面不同浓度的黄曲霉毒素进行识别,最后对模型判别正确率进行了验证。结果表明,选取四个最优波长(812.42,873.00,900.36和965.00 nm )时Fisher判别分析模型对训练集与验证集的准确率分别为87.4%和80.9%。该方法为含黄曲霉毒素玉米颗粒便携式检测仪器的开发,以及对田间霉变玉米自然代谢产生毒素的检测奠定了技术基础。 展开更多
关键词 最优波长 Fisher判别分析法 玉米颗粒 黄曲霉毒素 近红外高光谱图像
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中国花生核心种质的建立及与ICRISAT花生微核心种质的比较 被引量:30
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作者 姜慧芳 任小平 +6 位作者 廖伯寿 黄家权 雷永 陈本银 GUO B Z HOLBROOK C C UPADHYAYA H D 《作物学报》 CAS CSCD 北大核心 2008年第1期25-30,共6页
以中国花生种质资源数据库中记录的6390份花生资源为材料,以其基本数据、特征数据和评价数据为信息,采用分层分组聚类以及随机取样与必选资源相结合的方法,构建了由576份资源组成的花生核心种质,占基础收集品的9.01%。除出仁率外,核心... 以中国花生种质资源数据库中记录的6390份花生资源为材料,以其基本数据、特征数据和评价数据为信息,采用分层分组聚类以及随机取样与必选资源相结合的方法,构建了由576份资源组成的花生核心种质,占基础收集品的9.01%。除出仁率外,核心种质与基础收集品种间的其他14个性状平均值和多样性指数差异均不明显,表明本研究建立的核心种质是有效的。与ICRISAT花生微核心种质的比较,中国花生资源在龙生型和珍珠豆型方面具有优势,叶片长、叶片宽、种子长、种子宽的遗传多样性丰富;而ICRISAT花生资源在多粒型和普通型方面具有优势,且植株高度和总分枝数的遗传多样性比中国花生资源丰富。 展开更多
关键词 花生资源 中国核心种质 ICRISAT核心种质 遗传多样性
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黄瓜黑色果刺基因染色体定位及候选基因分析 被引量:11
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作者 刘书林 顾兴芳 +4 位作者 苗晗 王烨 Yiqun Weng Todd C Wehner 张圣平 《中国农业科学》 CAS CSCD 北大核心 2014年第1期122-132,共11页
【目的】黄瓜作为重要的果菜类蔬菜,果实品质一直是黄瓜育种研究的重点。果实品质包括内在品质和外观品质,其中外观品质对黄瓜的商品性具有重要影响。果刺颜色作为黄瓜重要的品质性状之一,对其进行遗传分析和基因定位将有助于了解果刺... 【目的】黄瓜作为重要的果菜类蔬菜,果实品质一直是黄瓜育种研究的重点。果实品质包括内在品质和外观品质,其中外观品质对黄瓜的商品性具有重要影响。果刺颜色作为黄瓜重要的品质性状之一,对其进行遗传分析和基因定位将有助于了解果刺颜色遗传的分子机理,为黄瓜果实性状改良提供理论依据和技术支撑,同时也可为刺色基因的精细定位及克隆奠定基础。【方法】研究利用黄瓜白色果刺自交系GY14(P1)和黑色果刺自交系NC76(P2)为亲本构建遗传群体,进行黄瓜果刺颜色的遗传分析。以F2分离群体为试材,应用分离群体分组分析法(BSA)和2 112对SSR引物进行SSR分析,结合9 930黄瓜全基因组序列信息和100份核心种质重测序结果开发新标记,对初定位区域进行标记加密。采用JoinMap 4.0作图软件和MapInspect软件构建连锁群并完成连锁群与染色体的对应,实现黄瓜黑色果刺性状的基因定位。运用生物信息学,在定位区域进行候选基因分析。利用包含156个株系的重组自交系(RILs)群体,对黑色果刺基因紧密连锁的两侧翼分子标记进行验证,确定标记用于分子标记辅助选择(MAS)育种的准确性。【结果】研究表明,黄瓜自交系NC76的黑色果刺符合质量性状遗传特点,由显性单基因B控制,黑色对白色为显性。初步定位筛选获得了与B基因连锁的8对SSR引物,将B定位于黄瓜4号染色体(Chr.4)上,最近的连锁标记为SSR22231,遗传距离为10.8 cM;根据初定位区域的序列信息,设计合成了新的SSR引物212对和Indel引物25对,利用这些引物对双亲和F2群体DNA进行分析,最终构建了一个包含14个SSR标记和1个InDel标记的分子标记连锁群,获得与B连锁的两侧翼标记SSRB-181和SSRB-130,遗传距离分别为2.0 cM和1.6 cM,该区段物理距离为422.1 kb,有60个预测候选基因,推测Csa4G003095和Csa4G001690是与黑色果刺形成相关性较大的候选基因。与B紧密连锁的两侧翼标记用于MAS育种的准确率分别为96.8%和96.2%,其中SSRB-181对黑色果刺植株鉴定的准确率达到100%,将在MAS育种发挥重要作用。【结论】黄瓜自交系NC76的黑色果刺性状由显性单基因控制,该基因位于Chr.4上422.1 kb范围内,两侧翼标记为SSRB-181和SSRB-130,遗传距离为3.6 cM。本研究结果为黑色果刺基因的精细定位和克隆及MAS育种奠定了良好基础。 展开更多
关键词 黄瓜 黑色果刺 染色体定位 SSR标记 候选基因 CUCUMIS SATIVUS L
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水稻抗稻瘟病基因Pi-ta的分子标记辅助选择 被引量:110
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作者 王忠华 贾育林 +1 位作者 吴殿星 夏英武 《作物学报》 CAS CSCD 北大核心 2004年第12期1259-1265,共7页
利用已建立的水稻抗稻瘟病基因Pi ta显性分子标记对 30个品系和 1 57个来自不同国家的一些水稻品种进行分子鉴定 ,并采用稻瘟病菌菌株ZN57(IC 1 7)和ZN6 1 (IB 4 9)人工接种试验进行致病性测试。结果表明 ,大部分品系和少数水稻品种含... 利用已建立的水稻抗稻瘟病基因Pi ta显性分子标记对 30个品系和 1 57个来自不同国家的一些水稻品种进行分子鉴定 ,并采用稻瘟病菌菌株ZN57(IC 1 7)和ZN6 1 (IB 4 9)人工接种试验进行致病性测试。结果表明 ,大部分品系和少数水稻品种含抗病基因Pi ta ,且对稻瘟病菌菌株ZN57和ZN6 1表现抗病反应。除此之外 ,利用两对显性分子标记YL1 55 YL87和YL1 83 YL87对 350个杂交F3代株系进行早期筛选 ,得到 1 1 8个抗病基因Pi ta纯合的株系。这些株系田间抗性调查结果表明 ,抗病基因存在与否与田间抗性相吻合。因Pi ta基因与许多其他抗病基因紧密连锁 ,而使含有Pi ta基因的品种具有广谱抗性 ,由此确立了Pi ta基因显性分子标记在育种辅助选择中的应用价值。 展开更多
关键词 水稻 抗稻瘟病基因Pi-ta 分子标记 辅助选择
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