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Variation and Cluster Analysis on Leaf Characters from Different Provenance Sources of Polygonum multiflorum Thunb 被引量:2
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作者 韦艳梅 王凌晖 +2 位作者 曹福亮 韦山青 梁耀丹 《Agricultural Science & Technology》 CAS 2010年第6期94-98,共5页
[Objective] The aim was to study the variation of leaf characters from different provenance sources of Polygonum multiflorum Thunb,as well as to carry out cluster analysis on P.multiflorum from different provenance so... [Objective] The aim was to study the variation of leaf characters from different provenance sources of Polygonum multiflorum Thunb,as well as to carry out cluster analysis on P.multiflorum from different provenance sources to provide basis for the classification,identification,breeding and improved variety selection of P.multiflorum.[Method] Leaf shape characters of 31 copies of germplasm resources in the major distribution region of the whole country were determined,and the genetic variation of P.multiflorum leaves from different producing areas was analyzed.[Result] The leaf characters of single plant of the same experimental provenance source of P.multiflorum were relatively stable,the variation was mainly found on the single leaf area,1/2 leaf width,leaf width and other indicators;the variation of each leaf character among different provenance sources was obvious,and the variation was mainly found on the single leaf weight,leaf area,1/2 leaf width,leaf length and other indicators.The correlation analysis of each leaf character in P.multiflorum suggested that the single leaf area and single leaf weight showed extremely significant positive correlation with leaf length,1/2 leaf width,leaf width,leaf thickness and leaf stem length,while the single leaf area and single leaf weight showed significant negative correlation with WWR(leaf width/1/2 leaf width)and LWR(leaf length/1/2 leaf length),in addition,several macroscopic leaf characters such as leaf length,1/2 leaf width,leaf width,leaf stem length showed extremely positive correlation.The main component analysis result suggested that the contribution rate of accumulation variance of the front three main components was up to 97.4%,which could better reflect the comprehensive performance of leaf characters of different provenance sources of P.multiflorum.The cluster analysis showed that the experimental 31 copies of P.multiflorum provenance sources should be divided into three classes,the first class was distributed in the Middle,Western of Guizhou,northwestern of Guangxi and western areas with higher altitude;the second class was distributed in Hunan,Hubei,Sichuan,Guangdong and the most area of Guangxi;the third class was distributed in Anhui,Jiangsu and Henan and Shandong.[Conclusion] Cluster analysis of leaf characters indicated that the kinds of provenance sources which the geographical position was closer could be got together.The study had provided a certain basis for the classification of P.multiflorum. 展开更多
关键词 Polygonum multiflorum Thunb leaf characters VARIATION Cluster analysis
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Biological characters and rDNA ITS sequences of pathogen of poplar leaf blight 被引量:4
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作者 JI Hong-fang YANG Qian SONG Rui-qing 《Journal of Forestry Research》 SCIE CAS CSCD 2006年第1期17-20,共4页
DNA was extracted from the strain of pathogen of poplar leaf blight using a modified CTAB method. ITS sequence (601bp) was initially amplified from the pathogen by using the universal primers ITSl and ITS4 (registe... DNA was extracted from the strain of pathogen of poplar leaf blight using a modified CTAB method. ITS sequence (601bp) was initially amplified from the pathogen by using the universal primers ITSl and ITS4 (registered No, DQ011257). Comparing to the nucleotide sequences acquired from GenBank database, the strain is clustered into the homogeneity with Alternaria alternate (AY787684) and Alternaria alternate (AY354228), with a homology of 98%, thus the strain was checked as Alternaria alternata (Fr.) Keissler. The optimal conditions for conidia germination and mycelium growth of the pathogen were tested, The optimal temperature for conidia germinating and mycelium growth is 25℃, and the optimal pH value is 6. Mycelium grows rather slowly at 10℃ and 30℃ and growth stops at above 35 ℃. Among the six culture mediums tested, PDA + poplar leaf juice medium is most favorable for mycelium growth. 展开更多
关键词 PATHOGEN Popular leaf blight Alternaria alternate rDNA ITS sequences Biological characteristics
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Study on the stomatal characters of rice plant I. A new technique of samplepre paration for observ ing the stomatal characters of rice leaf 被引量:2
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《Chinese Rice Research Newsletter》 2000年第3期7-8,共2页
关键词 A new technique of samplepre paration for observ ing the stomatal characters of rice leaf Study on the stomatal characters of rice plant I
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Research on Characters of Leaf Epidermal Cells' Quantities of Solanaceous Vegetable Crops
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作者 YU Longfeng AN Fuquan +1 位作者 GAO Jinhe LI Fuheng 《Journal of Northeast Agricultural University(English Edition)》 CAS 2010年第3期1-5,共5页
Tomatoes, peppers and eggplants' seedings were used as experiment materials to study the leaf development mechanism of solanaceous vegetable crops by using blot observation method. Results showed that an increasing t... Tomatoes, peppers and eggplants' seedings were used as experiment materials to study the leaf development mechanism of solanaceous vegetable crops by using blot observation method. Results showed that an increasing trend was presented at the density of cells and stomata in upper and lower epidermis, but a declined trend was presented at the cells' diameters and the size of stomata with the joint position rising. At the same joint position, no matter in adaxial side or abaxial side, there were some differences among cells diameters, size of stomata, density of cells and stomata. 展开更多
关键词 solanaceous vegetable crop leaf quantitative character
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Systematic Importance of Leaf Anatomical Characters in Some Species of Microcos Linn. Section Eumicrocos Burret. in Nigeria
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作者 Emmanuel Oyeniyi Shokefun Abiodun Emmanuel Ayodele Akinwunmi Johnson Akinloye 《American Journal of Plant Sciences》 2016年第1期108-117,共10页
The leaf anatomy of six Microcos L. species belonging to section Eumicrocos in Nigeria was investigated by transverse sectioning of the lamina and examined by light microscope to determine their taxonomic significance... The leaf anatomy of six Microcos L. species belonging to section Eumicrocos in Nigeria was investigated by transverse sectioning of the lamina and examined by light microscope to determine their taxonomic significance in species delimitation and classification. The common anatomical characteristics in all the species are as follows: the uniseriate epidermis;the hypostomatic and bifacial leaves;presence of 2 layers of palisade tissues;presence of bundle sheath extension to both epidermises;presence of glandular and non-glandular trichomes;presence of secretory ducts on abaxial surface;presence of druse crystal in the mesophyll and midrib and;sclerenchyma cells associated with the phloem. Anatomical characters which are significant for species delimitation include: the presence/absence of sclerenchyma cells associated with the xylem in the midrib;presence/absence of starch grains in the mesophyll and midrib;the presence/absence of secretory ducts on the adaxial surface of the midrib;the presence/absence of medullary plates in midrib;the number of secretory ducts in the midrib and the midrib adaxial outline. The section can be separated into two distinct groups based on the number of spongy tissue layers in the mesophyll, number of sclerenchyma cells associated with the phloem and presence/absence of sclerenchyma cells in xylem both groupings correlated with those obtained from foliar epidermal and pollen characters. The importance of these characters is discussed in relation to the taxonomy of the taxon. 展开更多
关键词 leaf Anatomy Microcos TAXONOMY NIGERIA
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Dynamic DNA methylation modification in catechins and terpenoids biosynthesis during tea plant leaf development 被引量:1
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作者 Jiahao Chen Yang Hu +3 位作者 Zhangsheng Zhu Peng Zheng Shaoqun Liu Binmei Sun 《Horticultural Plant Journal》 2025年第2期906-920,共15页
DNA methylation plays important roles in regulating gene expression during development.However,little is known about the influence of DNA methylation on secondary metabolism during leaf development in the tea plant(Ca... DNA methylation plays important roles in regulating gene expression during development.However,little is known about the influence of DNA methylation on secondary metabolism during leaf development in the tea plant(Camellia sinensis).In this study,we combined the methylome,transcriptome,and metabolome to investigate the dynamic changes in DNA methylation and its potential regulatory roles in secondary metabolite biosynthesis.In this study,the level of genomic DNA methylation increased as leaf development progressed from tender to old leaf.It additionally exhibited a similar distribution across the genomic background at the two distinct developmental stages studied.Notably,integrated analysis of transcriptomic and methylomic data showed that DNA hypermethylation primarily occurred in genes of the phenylpropanoid,flavonoid,and terpenoid biosynthesis pathways.The effect of methylation on transcription of these secondary metabolite biosynthesis genes was dependent on the location of methylation(i.e.,in the promoter,gene or intergenic regions)and the sequence context(i.e.,CpG,CHG,or CHH).Changes in the content of catechins and terpenoids were consistent with the changes in gene transcription and the methylation state of structural genes,such as serine carboxypeptidase-like acyltransferases 1A(SCPL1A),leucoanthocyanidin reductase(LAR),and nerolidol synthase(NES).Our study provides valuable information for dissecting the effects of DNA methylation on regulation of genes involved in secondary metabolism during tea leaf development. 展开更多
关键词 Camellia sinensis DNA methylation leaf development CATECHINS TERPENOIDS Gene regulation
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Rapid springtime leaf osmotic adjustment,but low late-seasonal and interannual variation in leaf turgor loss points in three temperate tree species 被引量:1
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作者 Norbert Kunert 《Journal of Forestry Research》 2025年第4期31-40,共10页
Leaf turgor loss point has been recognized as an important plant physiological trait explaining a species’drought tolerance( π_(tlp)).Less is known about the variation of π_(tlp) in time and how seasonal or interan... Leaf turgor loss point has been recognized as an important plant physiological trait explaining a species’drought tolerance( π_(tlp)).Less is known about the variation of π_(tlp) in time and how seasonal or interannual differences in water availability are affecting π_(tlp) as a static trait.I monitored the seasonal variation of π_(tlp) during a drought year starting in early spring with juvenile leaves and assessed the interannual variation in π_(tlp) of fully matured leaves among years with diverting water availability for three temperate broad-leaved tree species.The largest seasonal changes in π_(tlp) occurred during leaf unfolding until leaves were fully developed and matured.After leaves matured,no significant changes occurred for the rest of the vegetation period.Interannual variation that could be related to water availability was only present in one of the three tree species.The results suggest that the investigated species have a rapid period of osmotic adjustment early in the growing season followed by a period of relative stability,when π_(tlp) can be considered as a static trait. 展开更多
关键词 Drought leaf drought tolerance traits Tree mortality Turgor loss point
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随机存储下Leaf型仓储布局设计及其拣选路径策略研究
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作者 柳虎威 周丽 +2 位作者 赵俊辉 王繁 杨江龙 《工程数学学报》 北大核心 2025年第3期529-553,共25页
仓库布局设计是影响拣选作业行走路径和拣选效率的重要因素。在鱼骨布局和flying-V型布局的基础上,以货架摆放角度及斜向主通道角度为出发点,对Leaf型仓储布局进行研究,构建Leaf型仓储布局的有效存储面积利用率模型,探究货架摆放角度及... 仓库布局设计是影响拣选作业行走路径和拣选效率的重要因素。在鱼骨布局和flying-V型布局的基础上,以货架摆放角度及斜向主通道角度为出发点,对Leaf型仓储布局进行研究,构建Leaf型仓储布局的有效存储面积利用率模型,探究货架摆放角度及斜向主通道角度对有效存储面积的影响。进而构建Leaf型仓储布局中的S型和返回型拣选路径随机模型,并完成对其的近似计算与仿真验证。数值实验结果表明,在Leaf型仓储布局中,布局的改进对实际存储面积的影响较小,与鱼骨布局和flying-V型布局相差分别为1.6%与2.7%,可进一步对Leaf型仓储布局拣选行走路径进行研究,在特定货架摆放角度及斜向主通道角度下,返回型路径与S型路径均能取得最优值,且S型路径结果优于返回型路径。 展开更多
关键词 leaf型仓储布局 拣选路径 改进型布局 随机存储
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Studies on the anti-hair loss mechanism of Aquilaria sinensis leaf extract by integrated metabolomics and network pharmacology
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作者 Zhengang Peng Zhengwan Huang +1 位作者 Zhe Liu Xiaoxiao Lin 《日用化学工业(中英文)》 北大核心 2025年第6期767-778,共12页
The anti-hair loss mechanism of Aquilaria sinensis leaf extract(ASE)has been studied by using metabolomics and network pharmacology.Metabolomics was utilized to comprehensively identify the active constituents of ASE,... The anti-hair loss mechanism of Aquilaria sinensis leaf extract(ASE)has been studied by using metabolomics and network pharmacology.Metabolomics was utilized to comprehensively identify the active constituents of ASE,and the network pharmacology was used to elucidate their anti-hair loss mechanism,which was verified by molecular docking technology.572 active compounds were identified from the ASE by metabolomics methods,where there are 1447 corresponding targets and 492 targets related to hair loss,totaling 88 targets.20 core active substances were identified by constructing a network between common targets and active substances,which include vanillic acid,chorionic acid,caffeic acid and apigenin.The five key targets of TNF,TP53,IL6,PPARG,and EGFR were screened out by the PPI network analysis on 88 common targets.The GO and KEGG pathway enrichment analysis showed that the inflammation,hormone balance,cell growth,proliferation,apoptosis,and oxidative stress are involved.Molecular docking studies have confirmed the high binding affinity between core active compounds and key targets.The drug similarity assessment on these core compounds suggested that they have the potential to be used as potential hair loss treatment drugs.This study elucidates the complex molecular mechanism of ASE in treating hair loss,and provides a reference for the future applications in hair care products. 展开更多
关键词 metabolomics network pharmacology hair loss Aquilaria sinensis leaf extract molecular docking
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Pixel-by-Pixel Analysis of Soil and Leaf Coverage in Purslane: A CIELAB Approach
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作者 Abel Quevedo-Nolasco Graciano-Javier Aguado-Rodríguez +1 位作者 Francisco-Marcelo Lara-Viveros Nadia Landero-Valenzuela 《Agricultural Sciences》 2025年第2期227-239,共13页
This study utilized a computer application developed in Visual StudioTM using C# to extract pixel samples (RGB) from multiple images (26 images obtained from August 20, 2024, to September 22, 2024), of a purslane pot ... This study utilized a computer application developed in Visual StudioTM using C# to extract pixel samples (RGB) from multiple images (26 images obtained from August 20, 2024, to September 22, 2024), of a purslane pot taken from a top-down perspective at a distance of 30 cm. These samples were projected into the CIELAB color space, and the extracted pixels were plotted on the a*b* plane, excluding the luminance value. A polygon was then drawn around all the plotted pixels, defining the color to be identified. Subsequently, the application analyzed another image to determine the number of pixels within the polygon. These identified pixels were transformed to white, and the percentage of these pixels relative to the total number of pixels in the image was calculated. This process yielded percentages for brown (soil), green (leaf cover), and pink (stem color). A single polygon was sufficient to accurately identify the green and brown colors in the images. However, due to varying lighting conditions, customized polygons were necessary for each image to accurately identify the stem color. To validate the green polygon’s accuracy in identifying purslane leaves, all leaves in the image were digitized in AutoCADTM, and the green area was compared to the total image area to obtain the observed green percentage. The green percentage obtained with the polygon was then compared to the observed green percentage, resulting in an R2 value of 0.8431. Similarly, for the brown color, an R2 value of 0.9305 was found. The stem color was not subjected to this validation due to the necessity of multiple polygons. The R2 values were derived from percentage data obtained by analyzing the total pixels in the images. When sampling to estimate the proportion and analyzing only the suggested sample size of pixels, R2 values of 0.93049 for brown and 0.8088 for green were obtained. The average analysis time to determine the brown soil percentage using the polygon (BP) for 26 images with an average size of 1070 × 1210 pixels was 44 seconds. In contrast, sampling to estimate the proportion reduced the analysis time to 0.9 seconds for the same number of images. This indicates that significant time savings can be achieved while obtaining similar results. 展开更多
关键词 Automated Color Identification C# Application Color Space Soil Color Identification leaf Coverage
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Transcription factor BnaA1.WRKY53 is involved in regulation of auxin-induced leaf curling under boron deficiency in Brassica napus
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作者 Jinliang Yao Rui Cui +4 位作者 Beibei Fang Sheliang Wang Xiangsheng Ye Zhaojun Liu Fangsen Xu 《The Crop Journal》 2025年第4期1068-1080,共13页
Brassica napus(oilseed rape)is sensitive to boron(B)deficiency and exhibits young leaf curling in response to low-B stress at the seedling stage,which leads to reduced photosynthesis and plant growth.So far,no gene ha... Brassica napus(oilseed rape)is sensitive to boron(B)deficiency and exhibits young leaf curling in response to low-B stress at the seedling stage,which leads to reduced photosynthesis and plant growth.So far,no gene has been identified to be involved in B deficiency induced leaf curling.Our previous results showed the transcription factor BnaA1.WRKY53 might be involved in B-deficiency tolerance.However,altered BnaA1.WRKY53 expression does not influence B concentration in shoot,root and leaf cell walls,which suggests Bna A1.WRKY53 might be involved in other biological processes.Indeed,phenotypic and anatomical analyses revealed that BnaA1.WRKY53 negatively regulated the leaf curling induced by leaf epinasty by suppressing the overexpansion of palisade cells under B deficiency.Further transcriptome enrichment analysis of differentially expressed genes(DEGs)between wild-type and BnaA1.WRKY53overexpression line showed auxin response pathway was enriched.In addition,Arabidopsis DR5::GFP auxin reporter line showed B deficiency caused predominant auxin signal accumulation in the adaxial side and concomitant adaxial cell expansion,which indicated that B deficiency may induce leaf curling by altering auxin distribution.Phytohormone quantification and gene expression analysis demonstrated that BnaA1.WRKY53 prevent auxin overaccumulation in leaves by suppressing auxin biosynthetic genes under B deficiency.Furthermore,exogenous 1-naphthlcetic acid(NAA)treatment experiments revealed that high auxin could induce leaf curling and BnaA1.WRKY53 expression.Overall,these findings demonstrate that auxin and the transcription factor BnaA1.WRKY53 synergistically regulate leaf curling to maintain an optimal leaf area under B deficiency,and provide novel insights into the resistance mechanisms against B-deficiency-induced leaf curling in oilseed rape. 展开更多
关键词 Brassica napus Boron deficiency leaf curling leaf epinasty Adaxial side AUXIN WRKY
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Estimation model of potassium content in cotton leaves based on hyperspectral information of multi-leaf position
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作者 Qiushuang Yao Huihan Wang +6 位作者 Ze Zhang Shizhe Qin Lulu Ma Xiangyu Chen Hongyu Wang Lu Wang Xin Lü 《Journal of Integrative Agriculture》 2025年第11期4225-4241,共17页
Potassium(K)is a highly mobile nutrient element that continuously adjusts its demand strategy among and within cotton leaves through redistribution,indirectly leading to variations in the leaf potassium content(LKC,%)... Potassium(K)is a highly mobile nutrient element that continuously adjusts its demand strategy among and within cotton leaves through redistribution,indirectly leading to variations in the leaf potassium content(LKC,%)at different leaf positions.However,due to the interaction between light and leaf age,leaf sensitivity to this change varies at different positions,including the reflection and absorption of the spectrum.Selecting the optimal leaf position for monitoring is a crucial factor in the rapid and accurate evaluation of cotton LKC using spectral remote sensing technology.Therefore,this study proposes a comprehensive multi-leaf position estimation model based on the vertical distribution characteristics of LKC from top to bottom,aiming to achieve an accurate estimation of cotton LKC and optimize the strategy for selecting the monitored leaf position.Between 2020 and 2021,we collected hyperspectral imaging data of the main stem leaves at different positions from top to bottom(Li,i=1,2,3,...,n)during the cotton budding,flowering,and boll-setting stages.Vertical distribution characteristics,sensitivity differences,and spectral correlations of LKC at different leaf positions were investigated.Additionally,the optimal range of the dominant leaf position for monitoring was determined.Partial least squares regression(PLSR),random forest regression(RFR),support vector machine regression(SVR),and the entropy weight method(EWM)were employed to develop LKC estimation models for single-and multi-leaf positions.The results showed a vertical heterogeneous distribution of cotton LKC,with LKC initially increasing and then gradually decreasing from top to bottom;the average LKC of cotton reached its maximum value at the flowering stage.The upper leaf position demonstrated greater sensitivity to K and exhibited a stronger correlation with the spectrum.The selected dominant leaf positions for the three growth stages were L1-L5,L1-L4,and L1-L2,respectively.Based on the dominant leaf position monitoring range,the optimal single leaf position models for estimating LKC during the three growth stages were PLSR-L4,PLSR-L1,and SVR-L2,with the coefficient of determination of the validation set(R2val)being 0.786,0.580,and 0.768,and the root-mean-square error of the validation set(RMSEval)being 0.168,0.197,and 0.191,respectively.The multi-leaf position LKC estimation model was constructed by EWM with R2val being 0.887,0.728,and 0.703,and RMSEval being 0.134,0.172,and 0.209,respectively.In contrast,the newly developed multi-leaf position comprehensive estimation model yielded superior results,improving the model’s stability based on high accuracy,especially during the budding and flowering stages.These findings hold significant importance for investigating cotton LKC spectral models and selecting suitable leaf positions for field monitoring. 展开更多
关键词 HYPERSPECTRAL vertical heterogeneity leaf position COTTON leaf potassium content(LKC)
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Long-term leaf nitrogen and phosphorus dynamics and drivers in China's forests under global change
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作者 Chenxi Li Honglin He +6 位作者 Xinyu Zhang Xiaoli Ren Liang Shi Li Zhang Qian Xu Mengyu Zhang Yonghong Zhang 《Forest Ecosystems》 2025年第4期668-676,共9页
The leaf nitrogen(N)to phosphorus(P)ratio(N:P)is a critical indicator of nutrient dynamics and ecosystem function.Investigating temporal variations in leaf N:P can provide valuable insights into how plants adapt to en... The leaf nitrogen(N)to phosphorus(P)ratio(N:P)is a critical indicator of nutrient dynamics and ecosystem function.Investigating temporal variations in leaf N:P can provide valuable insights into how plants adapt to environmental changes and nutrient availability.However,limited research has been conducted on long-term temporal leaf N:P variation over a range of temperature zones.Using long-term monitoring data from the Chinese Ecosystem Research Network(CERN),we investigated temporal changes in leaf N and P stoichiometry for 50 dominant tree species from 10 typical forest sites across temperate and subtropical regions,and identified the underlying mechanisms driving these changes.For both regions combined,leaf P concentration of the 50 dominant tree species decreased(20.6%),whereas leaf N:P increased(52.0%)from 2005 to 2020.Leaf P decreased and leaf N:P increased in 67% and 69% of the tree species,respectively.The leaf N:P increase was primarily driven by the tree species in eastern subtropical forests,where global change factors and soil nutrients explained 68% of leaf N:P variation.The P limitation exhibited by tree species in eastern subtropical forest ecosystems intensified over time,and elevated temperature and CO_(2) levels,coupled with decreased soil available P concentrations,appear to be the main factors driving long-term leaf N:P increases in these forests.Investigating long-term variations in soil nutrients together with global change factors will improve our understanding of the nutrient status of forest ecosystems in the context of global change and will support effective forest ecosystem management. 展开更多
关键词 leaf nitrogen(N) leaf phosphorus(P) leaf N:P Temporal trends Global change factors Soil available phosphorus
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A Convolutional Neural Network Based Optical Character Recognition for Purely Handwritten Characters and Digits
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作者 Syed Atir Raza Muhammad Shoaib Farooq +3 位作者 Uzma Farooq Hanen Karamti Tahir Khurshaid Imran Ashraf 《Computers, Materials & Continua》 2025年第8期3149-3173,共25页
Urdu,a prominent subcontinental language,serves as a versatile means of communication.However,its handwritten expressions present challenges for optical character recognition(OCR).While various OCR techniques have bee... Urdu,a prominent subcontinental language,serves as a versatile means of communication.However,its handwritten expressions present challenges for optical character recognition(OCR).While various OCR techniques have been proposed,most of them focus on recognizing printed Urdu characters and digits.To the best of our knowledge,very little research has focused solely on Urdu pure handwriting recognition,and the results of such proposed methods are often inadequate.In this study,we introduce a novel approach to recognizing Urdu pure handwritten digits and characters using Convolutional Neural Networks(CNN).Our proposed method utilizes convolutional layers to extract important features from input images and classifies them using fully connected layers,enabling efficient and accurate detection of Urdu handwritten digits and characters.We implemented the proposed technique on a large publicly available dataset of Urdu handwritten digits and characters.The findings demonstrate that the CNN model achieves an accuracy of 98.30%and an F1 score of 88.6%,indicating its effectiveness in detecting and classifyingUrdu handwritten digits and characters.These results have far-reaching implications for various applications,including document analysis,text recognition,and language understanding,which have previously been unexplored in the context of Urdu handwriting data.This work lays a solid foundation for future research and development in Urdu language detection and processing,opening up new opportunities for advancement in this field. 展开更多
关键词 Image processing natural language processing handwritten Urdu characters optical character recognition deep learning feature extraction CLASSIFICATION
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Identification of a genomic region controlling broad-spectrum immunity to leaf rust in wheat–Agropyron cristatum 2P translocation lines
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作者 Xiajie Ji Shirui Xu +10 位作者 Zongyao Wang Haiming Han Jinpeng Zhang Shenghui Zhou Baojin Guo Xinming Yang Xiuquan Li Xiaomin Guo Taiguo Liu Lihui Li Weihua Liu 《Journal of Integrative Agriculture》 2025年第5期2015-2018,共4页
Wheat leaf rust,caused by Puccinia triticina(Pt),is one of the most devastating diseases in common wheat(Triticum aestivum L.)and can lead to heavy yield loss(Chai et al.2020).Leaf rust can result in 50%yield loss dur... Wheat leaf rust,caused by Puccinia triticina(Pt),is one of the most devastating diseases in common wheat(Triticum aestivum L.)and can lead to heavy yield loss(Chai et al.2020).Leaf rust can result in 50%yield loss during epidemic years(Huerta-Espino et al.2011;Gebrewahid et al.2020;Kolomiets et al.2021).Breeding varieties resistant to leaf rust have been recognized as the most effective and economical method to mitigate wheat losses caused by Pt.The narrow genetic basis of wheat constrains the number of cultivars resistant to leaf rust(Jin et al.2021). 展开更多
关键词 broad spectrum immunity leaf rustcaused Agropyron cristatum genomic region p translocation lines puccinia triticina pt leaf rust WHEAT
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Identification of Rice Leaf Width Gene FLW11 Through Genome-Wide Association Study and Functional Analysis
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作者 YANG Yulu ZHANG Yanfang +14 位作者 LIU Xiong ZHANG Lihua HUANG Jingfen SHEN Lixing ZHAO Huibo SHEN Lan ZHANG Qiang ZHU Li HU Jiang REN Deyong GAO Zhenyu DONG Guojun QIAO Weihua QIAN Qian ZHANG Guangheng 《Rice science》 2025年第6期756-760,I0018-I0023,共11页
The width of rice leaves determines the size of the photosynthetic area.Optimizing rice leaf width can improve the photosynthetic rate,thereby increasing rice yield.In this study,a genome-wide association study(GWAS)w... The width of rice leaves determines the size of the photosynthetic area.Optimizing rice leaf width can improve the photosynthetic rate,thereby increasing rice yield.In this study,a genome-wide association study(GWAS)was conducted by 225 rice germplasm resources to explore the genetic basis of rice flag leaf width(FLW).We identified nine QTLs associated with FLW(qFLWs),with phenotypic contribution rates ranging from 3.17%to 14.37%.Near-isogenic lines(NILs)were developed for fine-mapping of qFLW11,and the function of FLW11 was further verified.We narrowed down q FLW11 to an 87-kb interval,which contains five genes. 展开更多
关键词 functional analysis genome wide association study rice leaf width flag leaf width rice germplasm resources qtl photosynthetic rate phenotypic contribution rates
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Transcriptomic analysis uncovers the red leaf coloration mechanism in Euonymus sacrosancta Koidz
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作者 Xinyan Gao Zhongjia Yuan +5 位作者 Haoda Liu Yang Liu Ying Wang Lianfeng Xu Huihui Zhang Xuemei Liu 《Journal of Forestry Research》 2025年第5期245-259,共15页
Two leaf color variants red-leaf(R-type)and common-leaf(G-type)of Euonymus sacrosancta Koidz.,were employed as experimental materials to elucidate the molecular mechanisms underlying chromatic transition.Physiological... Two leaf color variants red-leaf(R-type)and common-leaf(G-type)of Euonymus sacrosancta Koidz.,were employed as experimental materials to elucidate the molecular mechanisms underlying chromatic transition.Physiological profiling identified anthocyanins and flavo-noids as the predominant pigments responsible for the red foliar phenotype,which exhibited reduced chlorophyll and carotenoid accumulation but elevated soluble sugars and proteins.Comparative transcriptomic analysis revealed that differentially expressed genes(DEGs)between R-type and G-type were significantly enriched in flavonoid biosynthe-sis and carotenoid metabolism pathways.The up-regulation of 22 key genes of anthocyanin synthesis(e.g.,CHS,CHI,LAR,LDOX and UFGT)in R-type may lead to the phenotype of red leaves through the increase of anthocyanin accumula-tion.The downregulated expression of 13 carotenoid syn-thesis-related genes(e.g.,PSY,PDS and VDE)and 6 carot-enoid degradation genes(e.g.,ABA2,CYP707A and NCED)may lead to lower carotenoid content in R-type compared to G-type.Combined with weighted gene co-expression network analysis(WGCNA),five candidate genes(EsLAR,EsLDOX,EsPDS,EsCYP707A and EsABA2)were screened from two modules highly correlated with anthocyanin con-tent in E.sacrosancta leaves.These genes may play key regulatory roles in leaf coloration and could serve as candi-date genetic resources for leaf color improvement in E.sac-rosancta.Additionally,transcription factors such as C2H2s,C3Hs,and WRKYs were identified as potential regulators in the formation of R-type in E.sacrosancta.This study pro-vides the first systematic elucidation of the transcriptional regulatory network governing red-leaf formation in E.sac-rosancta,establishing a critical theoretical foundation for molecular breeding in ornamental plants. 展开更多
关键词 Euonymus sacrosancta TRANSCRIPTOME leaf coloration ANTHOCYANIN Carotenoids
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Leaf Morphological Variation and Heterosis on Hybrid Progenies of Populus ussuriensis and P.simonii×P.nigra
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作者 Heng Zhang Meng Wang +9 位作者 Dong Zeng Yunbo Xu Dongyuan Guo Xuanchen Liu Zhanqi Ren Jinzi Zhang Yuhang Liu Qiuyu Wang Shuo Yu Guanzheng Qu 《Phyton-International Journal of Experimental Botany》 2025年第10期3205-3216,共12页
Hybridization remains an important method for breeding new poplar varieties.It results in significant variation in leaf phenotype among parents and offspring,and among offspring themselves.This study aimed to investig... Hybridization remains an important method for breeding new poplar varieties.It results in significant variation in leaf phenotype among parents and offspring,and among offspring themselves.This study aimed to investigate whether leaf shape variations were similar in offspring produced from reciprocal crosses.Specifically,two hybrid combinations were produced:the direct cross with Populus ussuriensis as the maternal parent and P.simonii×P.nigra as the paternal parent(HY53),and the reciprocal cross with P.simonii×P.nigra as the maternal parent and P.ussuriensis as the paternal parent(HY268).Using 3-month-old rooted cuttings from 40 clones(36 F1 hybrids and their parents)growing in a greenhouse,we measured and analyzed 14 leaf morphological traits to assess genetic variation and heterosis.The results showed HY53 clones generally exhibited greater average height than HY268 clones.Leaf phenotypes differed between the two hybrid combinations,with significant differences observed among parents and offspring for almost all traits,as revealed by analysis of variance(ANOVA).The phenotypic coefficient of variation was higher in HY268 clones.Additionally,leaf traits demonstrated high repeatability.Notably,some hybrid offspring exhibited positive or negative mid-parent heterosis,as well as over-parent heterosis for certain leaf phenotypes.The systematic cluster analysis further indicated distinct separation among HY268 clones.This research provides valuable materials for poplar breeding and offers insights into hybrid vigor in wood plants.The findings highlight the importance of reciprocal crossing in influencing leaf phenotype variation and heterosis,offering practical insights for future breeding strategies. 展开更多
关键词 HETEROSIS reciprocal crosses leaf phenotypes Populus breeding
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