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Comparative Study on Leaf Morphology-Venation Pattern of Hedyotis auricularia L.and Its Adulterants
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作者 Luxiao MENG Feipeng HUANG +3 位作者 Xinxin LU Piaoling HUANG Hailin LU Zhonghua DAI 《Medicinal Plant》 2025年第1期35-38,54,共5页
[Objectives]To compare the leaf morphology and leaf venation patterns of Hedyotis auricularia L.and its adulterants,such as Mitracarpus hirtus(L.)DC.,Spermacoce pusilla Wall.and Spermacoce alata Aubl.,produced in Guan... [Objectives]To compare the leaf morphology and leaf venation patterns of Hedyotis auricularia L.and its adulterants,such as Mitracarpus hirtus(L.)DC.,Spermacoce pusilla Wall.and Spermacoce alata Aubl.,produced in Guangxi,so as to provide a simple and rapid identification method for the identification of H.auricularia L.in Guangxi.[Methods]LMVP(leaf morphology-venation pattern)identification method was used to study the characteristics of leaf morphology-venation pattern.[Results]Characteristics of leaf morphology-venation pattern:(i)H.auricularia L.:circular knotted-curved pinnate leaf venation without reaching the margin;the primary veins run straight without branches,the number of secondary veins is 5 to 9,and the angles included in tertiary veins are mostly near right angles or obtuse angles.(ii)M.hirtus(L.)DC.:curved pinnate leaf venation without reaching the margin;the primary veins run straight without obvious changes,the number of secondary veins is 3 to 5,and the tertiary veins are slender,and the included angles are mostly acute.(iii)S.pusilla Wall.:curved leaf venation without reaching the leaf margin;there are 4 to 5 pairs of secondary veins,most of which are opposite;the angle between the secondary veins and the primary veins in the middle and near the petiole is mostly medium acute angle,and the extension of the tertiary veins has no fixed direction.(iv)S.alata Aubl.:circular knotted-curved pinnate leaf venation;the primary veins are convex and straight without branches,and there are 4 to 6 pairs of secondary veins,alternating.The angle between secondary veins and primary veins is mostly medium acute angle,the angle between tertiary veins and secondary veins is near right angle,and the tertiary veins are mostly transversely extended.[Conclusions]The leaf morphology-venation patterns of the above-mentioned H.auricularia L.and M.hirtus(L.)DC.,S.pusilla Wall.,and S.alata Aubl.can be used as their identification features,and the identification method has certain operability,which provides an identification idea for the identification of Chinese herbal medicines. 展开更多
关键词 Hedyotis auricularia L. Mitracarpus hirtus(L.)DC. Spermacoce pusilla Wall. Spermacoce alata Aubl. leaf venation pattern
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DISTRIBUTION PATTERNS OF LEAF AREA INDEX FOR MAJOR CONIFEROUS FOREST TYPES IN CHINA 被引量:4
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作者 Luo Tianxiang Li Wenhua Zhao Shidong Commission for Integrated Survey of Natural Resources, CAS, Beijing 100101 The People’s Republic of China 《Journal of Geographical Sciences》 SCIE CSCD 1997年第4期61-73,共13页
Leaf area index (LAI) of natural vegetation is recognized as the most important variable for measuring vegetation structure over large areas, and for relating it to energy and mass exchange, which has been successfull... Leaf area index (LAI) of natural vegetation is recognized as the most important variable for measuring vegetation structure over large areas, and for relating it to energy and mass exchange, which has been successfully estimated from satellite resolution sensors. In this paper, according to the statistical analysis based on a lot of forest plots, the mathematical models of LAI distribution patterns in the hydro thermal spaces for five coniferous forest types in China were established. For the cold temperate larch forests growing in the dry and cold climate, their LAI increases with the increasing of warm index and precipitation in the way of hyperbolic quadratic surface. For the cold temperate spruce fir forests and temperate Pinus tabulaeformis forests, their LAI is negatively related to the annual mean air temperature in the way of the natural exponential curve, in order to adapt to the water oppressed environments. For the subtropical Pinus massoniana forests and Cunninghamia lanceolata forests growing in the warm and moist climate, their LAI is related to the annual mean air temperature in the way of the parabolic quadratic curve. 展开更多
关键词 leaf area index hydro thermal space distribution pattern.
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The influence of selective cutting of mixed Korean pine(Pinus koraiensis Sieb.et Zucc.) and broad-leaf forest on rare species distribution patterns and spatial correlation in Northeast China 被引量:4
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作者 Binbin Kan Qingcheng Wang Wenjuan Wu 《Journal of Forestry Research》 SCIE CAS CSCD 2015年第4期833-840,共8页
This study aimed to demonstrate change in spatial correlation between Korean pine (Pinus koraiensis Sieb. et Zucc.) and three rare species, and change in spatial distribution of four species in response to a range o... This study aimed to demonstrate change in spatial correlation between Korean pine (Pinus koraiensis Sieb. et Zucc.) and three rare species, and change in spatial distribution of four species in response to a range of selective cutting intensities. We sampled three plots of mixed Korean pine and broad-leaf forest in Lushuihe Forestry Bureau of Jilin province, China. Plot 1, a control, was unlogged Korean pine broad-leaf forest. In plots 2 and 3, Korean pine was selectively cut at 15 and 30 % intensity, respectively, in the 1970s. Other species were rarely cut. We used point-pattern analysis to research the spatial distributions of four tree species and quantify spatial correlations between Korean pine and the other three species, Amur linden (Tilia amurensis Rupr.), Manchurian ash (Fraxinus mandshurica Rupr.), and Mongolian oak (Quercus mongolica Fisch.) in all three plots. The results of the study show that selective cutting at 15 % intensity did not significantly change either the species spatial patterns or the spatial correlation between Korean pine and broadleaf species. Selective cutting at 30 % intensity slightly affected the growth of Korean pine and valuable species in forest communities, and the effect was considered nondestructive and recoverable. 展开更多
关键词 Korean pine broad-leaf forest Cuttingintensity Rare species Spatial pattern - Spatialcorrelation
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AI-Driven Pattern Recognition in Medicinal Plants: A Comprehensive Review and Comparative Analysis
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作者 Mohd Asif Hajam Tasleem Arif +2 位作者 Akib Mohi Ud Din Khanday Mudasir Ahmad Wani Muhammad Asim 《Computers, Materials & Continua》 SCIE EI 2024年第11期2077-2131,共55页
The pharmaceutical industry increasingly values medicinal plants due to their perceived safety and costeffectiveness compared to modern drugs.Throughout the extensive history of medicinal plant usage,various plant par... The pharmaceutical industry increasingly values medicinal plants due to their perceived safety and costeffectiveness compared to modern drugs.Throughout the extensive history of medicinal plant usage,various plant parts,including flowers,leaves,and roots,have been acknowledged for their healing properties and employed in plant identification.Leaf images,however,stand out as the preferred and easily accessible source of information.Manual plant identification by plant taxonomists is intricate,time-consuming,and prone to errors,relying heavily on human perception.Artificial intelligence(AI)techniques offer a solution by automating plant recognition processes.This study thoroughly examines cutting-edge AI approaches for leaf image-based plant identification,drawing insights from literature across renowned repositories.This paper critically summarizes relevant literature based on AI algorithms,extracted features,and results achieved.Additionally,it analyzes extensively used datasets in automated plant classification research.It also offers deep insights into implemented techniques and methods employed for medicinal plant recognition.Moreover,this rigorous review study discusses opportunities and challenges in employing these AI-based approaches.Furthermore,in-depth statistical findings and lessons learned from this survey are highlighted with novel research areas with the aim of offering insights to the readers and motivating new research directions.This review is expected to serve as a foundational resource for future researchers in the field of AI-based identification of medicinal plants. 展开更多
关键词 pattern recognition artificial intelligence machine learning deep learning image processing plant leaf identification
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‘茗科1号’茶鲜叶转录和代谢轮廓的模式识别研究
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作者 陈林 项丽慧 +2 位作者 宋振硕 陈键 张应根 《热带亚热带植物学报》 北大核心 2025年第3期241-252,共12页
为挖掘乌龙茶品种鲜叶的特征特性,以绿茶品种‘福鼎大毫茶’一芽二叶或三叶为对照(CK),分析比较了高香优质乌龙茶品种‘茗科1号’一芽二叶或三叶(TM)与中小开面二至四叶(MM)在转录和代谢水平的组成差异。结果表明,茶树品种特性和采摘标... 为挖掘乌龙茶品种鲜叶的特征特性,以绿茶品种‘福鼎大毫茶’一芽二叶或三叶为对照(CK),分析比较了高香优质乌龙茶品种‘茗科1号’一芽二叶或三叶(TM)与中小开面二至四叶(MM)在转录和代谢水平的组成差异。结果表明,茶树品种特性和采摘标准为影响茶鲜叶转录和代谢轮廓的重要因素,其中CK、TM和MM的转录与代谢轮廓相互间均有良好的模式区分。差异表达基因与差异代谢物的富集和关联分析结果表明,TM vs CK与MM vs TM的差异表达基因在分子功能、细胞组分和生物过程方面存在不同的GO功能富集模式,且前者拥有较多的生物过程和较少的细胞组分;“植物次生代谢产物的生物合成”、“精氨酸和脯氨酸代谢”与“类胡萝卜素生物合成”、“苯丙素的生物合成”、“甘氨酸、丝氨酸和苏氨酸代谢”分别是TM vsCK、MM vs TM在2种组学分析中的前20条共有KEGG富集代谢通路。TM vs CK中L-苯丙氨酸、反式肉桂酸和4-胍基丁酸丰度的显著降低,以及MM vs TM中胆碱丰度的显著提高和L-苯丙氨酸、L-色氨酸、L-高丝氨酸丰度的显著降低均与相应共富集代谢通路中多个基因的显著上调或下调表达密切相关。此外,MM vs TM中脱落酸丰度的显著提高与“类胡萝卜素生物合成”通路中紫黄质脱环氧化酶和番茄红素β-环化酶基因的显著上调表达高度相关。这可为阐明‘茗科1号’茶鲜叶生物学特征及其多茶类兼制特性提供参考依据。 展开更多
关键词 乌龙茶 鲜叶 转录组 代谢组 模式识别
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基于可拓语义与形状文法的汉代铜镜纹饰研究
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作者 李晶 车乐乐 《设计》 2025年第2期138-142,共5页
为解决汉代铜镜纹样在复用设计过程中,由于语义复杂导致的设计创新偏离其本质内涵、纹样造型设计单一以及创新困难的问题,深入挖掘其文化性与艺术性,并将其创新性地应用于现代产品设计中。首先,收集具有铜镜纹样寓意的特征词汇,并评估... 为解决汉代铜镜纹样在复用设计过程中,由于语义复杂导致的设计创新偏离其本质内涵、纹样造型设计单一以及创新困难的问题,深入挖掘其文化性与艺术性,并将其创新性地应用于现代产品设计中。首先,收集具有铜镜纹样寓意的特征词汇,并评估其可拓区间。接着,选取可拓区间最大的纹样,运用形状文法对典型纹样进行推演变换,以适应新的设计载体。最后,通过对可拓区间的图解验证,确保经过可拓语义与形状文法推演的纹样在保留原有时代特色的同时,符合现代大众的审美和需求。通过本研究的可拓语义与形状文法推演方法,成功解决了铜镜纹样在文化传承与创新发展中的难点,得到的纹样不仅保留了其原有的文化特色,还融合了现代审美特征,满足了现代市场的需求。因此,验证了这一方法对于铜镜纹饰传承的可行性,为传统文化的传承与发展提供了新的思路与方法。 展开更多
关键词 汉代铜镜 铜镜纹样 草叶纹镜 可拓语义 形状文法
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小麦TaMBD9基因敲除及其对叶夹角的影响 被引量:2
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作者 范姗姗 杜金强 +3 位作者 张新宁 吴玉杰 孟凡荣 李永春 《河南农业大学学报》 北大核心 2025年第1期29-37,共9页
【目的】创建小麦TaMBD9基因敲除材料,探讨该基因在小麦生长发育调控过程中的生物学功能。【方法】利用实时定量反转录聚合酶链反应(quantitative reverse transcription polymerase chain reaction,qRT-PCR)分析TaMBD9的表达特性,通过C... 【目的】创建小麦TaMBD9基因敲除材料,探讨该基因在小麦生长发育调控过程中的生物学功能。【方法】利用实时定量反转录聚合酶链反应(quantitative reverse transcription polymerase chain reaction,qRT-PCR)分析TaMBD9的表达特性,通过CRISPR-Cas9介导的基因编辑技术创建基因敲除小麦材料。【结果】表达分析显示,TaMBD9在小麦不同组织间存在差异表达,其中叶片中的表达量最高,且随发育进程有所波动。3个部分同源基因间表达水平存在一定差异,其中TaMBD9D的表达水平较高。获得了TaMBD9的3个部分同源基因均成功敲除的纯合突变小麦材料。表型分析发现,TaMBD9敲除导致小麦叶夹角明显增大。【结论】小麦TaMBD9在叶夹角调控过程中发挥重要功能。研究获得了TaMBD9基因敲除纯合株系,为开展小麦叶夹角分子调控机制研究提供了新材料。 展开更多
关键词 小麦 叶夹角 TaMBD9基因 基因敲除 表达模式
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氮肥基追比和种植模式对棉花氮素代谢和叶片衰老以及产量的影响 被引量:1
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作者 徐新龙 张巨松 +5 位作者 代健敏 席亚雯 李雪瑞 王莲 李蔚和 孙华键 《中国生态农业学报(中英文)》 北大核心 2025年第4期709-722,共14页
为确定新疆棉区棉花高产高效栽培的合理施肥策略,研究了氮肥基追比例对不同种植模式棉花氮素利用效率、叶片衰老特性及产量的影响。以‘新陆中84号’棉花品种为研究对象,于2022—2023年在新疆沙雅县海楼镇进行田间试验。采用裂区设计,以... 为确定新疆棉区棉花高产高效栽培的合理施肥策略,研究了氮肥基追比例对不同种植模式棉花氮素利用效率、叶片衰老特性及产量的影响。以‘新陆中84号’棉花品种为研究对象,于2022—2023年在新疆沙雅县海楼镇进行田间试验。采用裂区设计,以2种种植模式为主区:一膜六行(66 cm+10 cm宽窄行距、株距12 cm,M6)、一膜三行(76 cm等行距、株距6 cm,M3);以4种氮肥基追比例为副区:0:0(CK,不施氮)、0:10 (N0)、2:8(N2)、4:6(N4);共8个处理。施氮处理总施氮量均为320 kg·hm^(2)。本文测定了棉花不同生育期氮代谢酶及叶片衰老相关酶活性、氮素利用效率、产量及产量构成。结果表明,2022年和2023年M3N4处理的棉花可获得较高籽棉产量,分别为7342.59和8085.19 kg·hm^(-2),较M6N2处理(M6最优产处理)提高12.05%和6.18%;M3N4处理表现出更好的结铃性,单株铃数较M6N2处理增加10.17%,但单铃重平均减少1.48%。M3N4处理在盛花—盛铃期棉花功能叶可保持较高的酶活性,促进棉花氮代谢,延长叶片功能期;M3模式整体较M6模式的氮素最大积累速率(Vm)有所降低,氮素最大积累速率出现时间(T)略有推迟,快速累积持续持续天数(Δt)增加3.85~11.64 d,氮素快速增长期生长特征值(TG)提高4.23%~27.60%。M3模式下各氮肥处理棉株氮素总积累量均高于M6模式对应氮肥处理,M3N4处理营养器官氮素积累量显著高于其他处理;M3N4处理棉花氮肥农学利用率、氮肥回收率和氮肥偏生产力较于M6N2处理分别增加7.77%、10.56%和8.90%,但氮肥生理利用率降低3.03%。合理的氮肥基追比和种植模式可调控棉株个体和群体之间的关系,加快棉花氮代谢水平,增加棉株各器官氮素积累转运量,进而提高氮素利用效率,通过提高生理代谢酶活性延缓棉花叶片衰老,维持较高棉株单株铃数,从而充分发挥棉花生产潜力。在本试验条件下,选择76 cm等行距种植模式,氮肥基追比控制在4:6为增产最优组合。 展开更多
关键词 棉花 种植模式 氮肥基追比 氮素代谢 叶片衰老
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两个马铃薯品种冬、春种植模式下叶片糖苷生物碱合成代谢差异分析
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作者 祝兴喆 苏仙月 +4 位作者 苏旺 张红林 潘哲超 刘涛 徐笑宇 《园艺学报》 北大核心 2025年第7期1883-1900,共18页
为探究云南省冬(W)、春(S)种植模式下生境差异对不同基因型马铃薯叶片糖苷生物碱(steroidal glycoalkaoids,SGA)合成代谢的影响,以青薯9号(Q9)和丽薯6号(L6)为材料,通过比较蛋白质组学和代谢组学联合分析技术,分析了这两个品种在冬春季... 为探究云南省冬(W)、春(S)种植模式下生境差异对不同基因型马铃薯叶片糖苷生物碱(steroidal glycoalkaoids,SGA)合成代谢的影响,以青薯9号(Q9)和丽薯6号(L6)为材料,通过比较蛋白质组学和代谢组学联合分析技术,分析了这两个品种在冬春季节种植期间,处于块茎关键生长时期时叶片中的SGA代谢变化。结果表明:(1)SGA的含量在叶片中随着块茎的发育成熟总体呈上升趋势,但在块茎膨大期中的合成差异最为明显,因此,选择这一时期的叶片开展了基于两种比较模式(Q9-leafW vs.Q9-leafS;Q9-leafW vs.L6-leafW)的组学分析;(2)因品种基因型差异和种植模式引起的生境条件改变,从整体蛋白质表达调控及其导致的代谢物重分配水平上,对马铃薯叶片在两种比较模式下的全局代谢分化造成了初生和次生层面的显著影响;(3)在两种比较模式中分别鉴定到了4个与SGA生物合成高度相关的差异表达蛋白质和差异积累代谢物,它们在SGA生物合成路径的初级和次级代谢阶段中发挥了调控SGA合成积累的不同作用,这可能是引起叶片总SGA在含量和组分上显著差异的关键原因。 展开更多
关键词 马铃薯 种植模式 叶片 糖苷生物碱 组学
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文采报春苣苔PwDREB2s基因的克隆与表达分析
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作者 刘宝骏 付传明 +3 位作者 苏江 冼康华 何金祥 黄宁珍 《广西植物》 北大核心 2025年第3期542-554,共13页
脱水响应元件结合蛋白2(dehydration responsive element binding protein 2,DREB2)是一种转录因子,在模式植物应答干旱、高盐和热激胁迫中起调控作用。然而,在适应喀斯特干热石山环境的文采报春苣苔(Primulina wentsaii)中,这些基因的... 脱水响应元件结合蛋白2(dehydration responsive element binding protein 2,DREB2)是一种转录因子,在模式植物应答干旱、高盐和热激胁迫中起调控作用。然而,在适应喀斯特干热石山环境的文采报春苣苔(Primulina wentsaii)中,这些基因的功能尚不清楚。筛选对干热双重胁迫联合响应的文采报春苣苔DREB2同源基因,可为苦苣苔抗逆种质的创制提供新的基因储备。该研究首先根据文采报春苣苔转录组的序列信息设计特异引物,以gDNA和cDNA为模板分离PwDREB2s基因,然后通过生物信息学方法,对氨基酸序列、系统进化关系及保守基序进行分析,再使用半定量RT-PCR(sqRT-PCR)分析PwDREB2s基因在低温、热激、模拟干旱(渗透)、高盐、外源ABA及氧化等单一胁迫下的表达模式,最后选择能同时应答模拟干旱与热激的成员,利用实时荧光定量PCR(qRT-PCR)检测其在单一和复合干热处理中的转录本水平。结果表明:(1)分离获得了8条缺少内含子的PwDREB2s基因,编码198~386个氨基酸,拥有AP2/ERF结构域、核定位信号或转录激活域等典型特征序列;(2)PwDREB2A/2AL1/2AL2、PwDREB2D/2DL和PwDREB2F转录因子被分别归入A-2亚组的亚型1、亚型2和亚型3,PwDREB2EL1/2EL2转录因子则被归入A-6亚组;(3)SqRT-PCR分析表明PwDREB2s基因表达受多种单一胁迫的诱导,其中PwDREB2A/2AL1/2AL2/2D基因能同时应答模拟干旱与热激胁迫;(4)qRT-PCR结果揭示了在液体培养条件下,PwDREB2D基因对干热处理的应答具有组织特异性,仅能在根状茎中被强烈诱导。在土壤栽培条件下,与对照相比时,除PwDREB2D基因以外,PwDREB2A/2AL1/2AL2基因在自然干旱-热激复合胁迫中的转录反应显著增强。与单一的自然干旱和高温处理相比时,PwDREB2AL1/2AL2基因在自然干旱-热激复合胁迫中的表达水平显著升高。由此可见,PwDREB2AL1/2AL2基因在文采报春苣苔干热复合胁迫应答中可能发挥了重要的调控作用。 展开更多
关键词 文采报春苣苔 DREB2转录因子 肉质叶 干旱-热激复合胁迫 表达模式
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不同栽培模式对籽叶双收茶树新梢生理生化特性的影响
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作者 江丽 李朵姣 +7 位作者 胡新荣 沈英姿 郑寨生 翁晓星 刘淑婧 边晓东 袁名安 陈暄 《茶叶科学》 北大核心 2025年第5期783-794,共12页
为探明籽叶双收茶树新品系在不同栽培模式下的茶叶品质及代谢差异,调查了‘金茶1号’单株稀植与条栽密植模式下的物候期以及单芽、一芽一叶、一芽二叶的长度及百芽重,并对一芽二叶的品质及代谢产物进行研究。结果表明,‘金茶1号’单株... 为探明籽叶双收茶树新品系在不同栽培模式下的茶叶品质及代谢差异,调查了‘金茶1号’单株稀植与条栽密植模式下的物候期以及单芽、一芽一叶、一芽二叶的长度及百芽重,并对一芽二叶的品质及代谢产物进行研究。结果表明,‘金茶1号’单株稀植模式的单芽、一芽一叶、一芽二叶的长度及百芽重均大于条栽密植模式,生育期晚于条栽密植;单株稀植模式新梢的茶多酚、儿茶素及没食子酸含量分别比条栽密植模式下高3.96、5.06、1.19百分点,而总氨基酸与茶氨酸含量分别比条栽密植模式低1.27、0.21百分点。通过比较代谢组学研究,鉴定出163种显著差异代谢物,主要富集在氨基酸及多酚生物合成途径。单株稀植模式下‘金茶1号’的脱落酸、赤霉素和茉莉酸等含量显著高于条栽密植模式;而吲哚乙酸、6-糠氨基嘌呤及吲哚-丁酸显著低于条栽密植模式。研究阐明了不同栽培模式通过协同调控内源激素与代谢通路影响籽叶双收茶树鲜叶品质的机制,为产业化推广提供高效栽培的实践模式。 展开更多
关键词 茶树 栽培模式 籽叶双收 生物学特性 代谢机制
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清代早期瓷上蕉叶纹饰的艺术特征探析
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作者 刘子悦 《景德镇陶瓷》 2025年第2期83-86,共4页
作为中国传统吉祥文化的重要载体和象征,蕉叶纹饰被广泛运用到瓷器装饰之中,传递了国民对美好生活的向往和独特的审美理念。清代早期,在传统瓷上蕉叶纹装饰的基础上,从画面装饰、构图设计等方面具有了新的样式,体现了总体社会审美的转向... 作为中国传统吉祥文化的重要载体和象征,蕉叶纹饰被广泛运用到瓷器装饰之中,传递了国民对美好生活的向往和独特的审美理念。清代早期,在传统瓷上蕉叶纹装饰的基础上,从画面装饰、构图设计等方面具有了新的样式,体现了总体社会审美的转向,折射了帝王爱好和宗教思想的影响。通过对清代早期瓷上蕉叶纹饰艺术特征的分析,揭示不同身份的文化主体对陶瓷创作的影响,对进一步了解清代早期的社会风貌、文化观念具有一定的启发意义。 展开更多
关键词 蕉叶纹 清代早期 瓷器
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建兰新发叶芽高生长模型的构建及其生长发育规律探讨
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作者 张佳语 《热带农业科学》 2025年第9期24-29,共6页
分析建兰新发叶芽高生长发育规律,建立理想的生长模型,为兰花优质高效栽培生产提供参考依据。选用大棚栽培的忆香荷、君荷、高山春色3种建兰新发叶芽为研究材料,通过3种非线性模型Logistic、Gompertz和Von Bertalanffy建立新发叶芽高生... 分析建兰新发叶芽高生长发育规律,建立理想的生长模型,为兰花优质高效栽培生产提供参考依据。选用大棚栽培的忆香荷、君荷、高山春色3种建兰新发叶芽为研究材料,通过3种非线性模型Logistic、Gompertz和Von Bertalanffy建立新发叶芽高生长模型,并对建兰叶芽生长期进行阶段划分,探讨其生长发育规律。结果表明,3个品种的叶芽生长均符合植物的“S”型曲线生长的一般规律,3种模型也均能模拟建兰新发叶芽高的生长曲线,其中Logistic生长模型拟合优度更高,与实测值也更接近,在实际应用中效果更好。通过Logistic模型方程将建兰叶芽生长阶段划分为生长初期、生长盛期、生长后期,其中生长盛期持续时间较长且生长量大,其生长量占总生长量的63.23%以上。研究提出了建兰新发叶芽生长模型及其生长规律,为建兰后续高效栽培管理提供理论支撑。 展开更多
关键词 建兰 新发叶芽高 非线性生长模型 生长发育规律 栽培管理
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Recognition system of leaf images based on neuronal network 被引量:5
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作者 WANG Dai-lin ZHANG Xiu-mei LIU Ya-qiu 《Journal of Forestry Research》 SCIE CAS CSCD 2006年第3期243-246,共4页
In forest variety registration, visual traits of the plants appearance are widely used to discern different tree species. The new recognition system of leaf image strategy which based on neural network established to ... In forest variety registration, visual traits of the plants appearance are widely used to discern different tree species. The new recognition system of leaf image strategy which based on neural network established to administrate a hierarchical list of leaf images, some sorts of edge detection can be performed to identify the individual tokens of every image and the frame of the leaf can be got to differentiate the tree species. An approach based on back-propagation neuronal network is proposed and the programming language for the implementation is also Riven by using Java. The numerical simulations results have shown that the proposed leaf strategt is effective and feasible. 展开更多
关键词 Neuronal network Edge detection leaf images pattern recognition
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Latitudinal variation of leaf morphological traits from species to communities along a forest transect in eastern China 被引量:10
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作者 王瑞丽 于贵瑞 +3 位作者 何念鹏 王秋凤 赵宁 徐志伟 《Journal of Geographical Sciences》 SCIE CSCD 2016年第1期15-26,共12页
Comprehensive information on geographic patterns of leaf morphological traits in Chinese forests is still scarce.To explore the spatial patterns of leaf traits,we investigated leaf area(LA),leaf thickness(LT),specific... Comprehensive information on geographic patterns of leaf morphological traits in Chinese forests is still scarce.To explore the spatial patterns of leaf traits,we investigated leaf area(LA),leaf thickness(LT),specific leaf area(SLA),and leaf dry matter content(LDMC) across 847 species from nine typical forests along the North-South Transect of Eastern China(NSTEC) between July and August 2013,and also calculated the community weighted means(CWM) of leaf traits by determining the relative dominance of each species.Our results showed that,for all species,the means(± SE) of LA,LT,SLA,and LDMC were 2860.01 ± 135.37 mm2,0.17 ± 0.003 mm,20.15 ± 0.43 m2 kg–1,and 316.73 ± 3.81 mg g–1,respectively.Furthermore,latitudinal variation in leaf traits differed at the species and community levels.Generally,at the species level,SLA increased and LDMC decreased as latitude increased,whereas no clear latitudinal trends among LA or LT were found,which could be the result of shifts in plant functional types.When scaling up to the community level,more significant spatial patterns of leaf traits were observed(R2 = 0.46–0.71),driven by climate and soil N content.These results provided synthetic data compilation and analyses to better parameterize complex ecological models in the future,and emphasized the importance of scaling-up when studying the biogeographic patterns of plant traits. 展开更多
关键词 latitudinal pattern leaf morphological trait community weighted mean forest ecosystem North-South Transect of Eastern China
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Leaf Growth of Different Populations of Vetiveria zizanioides
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作者 Liu Jinxiang Peng Xuemei Yang Yunfei 《Animal Husbandry and Feed Science》 CAS 2014年第6期304-307,327,共5页
Large sample sampling was adopted in this paper for the statistical analysis of leaves of four populations of Vetiveria zizanioides ( introduced, local wild, domesticated wild populations of different years). The re... Large sample sampling was adopted in this paper for the statistical analysis of leaves of four populations of Vetiveria zizanioides ( introduced, local wild, domesticated wild populations of different years). The results showed that four populations varied in different degrees in terms of tiller height, leaf biomass, and leaf biomass ratio. Leaf length, leaf width, and ratio of leaf width to length of different populations also varied, but had similar power-function change regularity, and showed converging leaf biomass growth pattern and leaf growth process. 展开更多
关键词 Vetiveria zizanioides leaf Growth pattern
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Dry Matter Partitioning, Nodulation and Seed Traits of Medium and Late Maturing Soybean Varieties as Affected by Planting Pattern and Plant Density
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作者 Daniel Markos Udai. R. Pal Elias Uragie 《Journal of Agricultural Science and Technology(B)》 2012年第1期142-150,共9页
An experiment was conducted on Fluvisols of Awassa for two consecutive years (2005-2006) to determine effects of planting pattern and plant density on dry matter accumulation, nodulation, protein and oil content in ... An experiment was conducted on Fluvisols of Awassa for two consecutive years (2005-2006) to determine effects of planting pattern and plant density on dry matter accumulation, nodulation, protein and oil content in early and late maturing soybean varieties. Results indicated that Awassa-95 variety produced significantly higher (P 〈 0.05) number of nodules/plant (NDN), nodule dry matter (NDM) and leaf dry matter (LDM at R2 (mid flowering) stage of soybean growth than that of variety Belessa-95). Similarly, variety Awassa-95 (45%) produced significantly higher protein content than variety Belessa-95 (40%). However, variety Belessa-95 accumulated significantly higher (P 〈 0.01) dry matter in straw, grain and total biomass at R7 (physiological maturity) stage of soybean growth than variety Awassa-95. Similarly, oil content of variety Belessa-95 (18.1%) was significantly (P 〈 0.05) higher than that of variety Awassa-95 (15.9%). Equidistant rows produced significantly higher (P 〈 0.05) NDM than either rectangular or paired rows. Moreover, soybean plants grown in both rectangular and equidistant rows produced significantly higher (P 〈 0.01) straw dry matter than those grown in paired rows; but, grain dry matter/plant (GDM) was significantly higher (P 〈 0.01) paired and rectangular rows compared to equidistant rows. Plant density also affected the per plant GDM production as it was significantly higher (P 〈 0.01) in 20 and 30 plants/m2 than higher plant densities (40 and 50 plants/m2). However, dry matter and yield components had strong negative association with protein content. In fact, strong positive correlation (R 〉 0.600) occurred between grain yield and its components with dry matter components at R2 (stem dry matter (SDM), leaf dry matter (LDM) and stem + nodule + leaf dry matter together known as TDM) and straw dry matter at R7 in both varieties. This study depicted that soybean plants that produce higher dry matter components at R2 would probably produce more straw dry matter, greater grain yield components and higher grain yield dry matter at later stages. 展开更多
关键词 leaf dry matter nodule dry matter protein content oil content plant density planting pattern.
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Timing Is Everything: Highly Specific and Transient Expression of a MAP Kinase Determines Auxin-Induced Leaf Venation Patterns in Arabidopsis 被引量:4
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作者 Vera Stanko Concetta Giuliani +7 位作者 Katarzyna Retzer Armin Djamei Vanessa Wahl Bernhard Wurzinger Cathal Wilson Erwin Heberle-Bors Markus Teige Friedrich Kragler 《Molecular Plant》 SCIE CAS CSCD 2014年第11期1637-1652,共16页
Mitogen-activated protein kinase (MAPK) cascades are universal signal transduction modules present in all eukaryotes. In plants, MAPK cascades were shown to regulate cell division, developmental processes, stress re... Mitogen-activated protein kinase (MAPK) cascades are universal signal transduction modules present in all eukaryotes. In plants, MAPK cascades were shown to regulate cell division, developmental processes, stress responses, and hormone pathways. The subgroup A of Arabidopsis MAPKs consists of AtMPK3, AtMPK6, and AtMPK10. AtMPK3 and AtMPK6 are activated by their upstream MAP kinase kinases (MKKs) AtMKK4 and AtMKK5 in response to biotic and abiotic stress. In addition, they were identified as key regulators of stomatal development and patterning. AtMPKIO has long been considered as a pseudo-gene, derived from a gene duplication of AtMPK6. Here we show that AtMPKIO is expressed highly but very transiently in seedlings and at sites of local auxin maxima leaves. MPK10 encodes a functional kinase and interacts with the upstream MAP kinase kinase (MAPKK) AtMKK2. mpklO mutants are delayed in flowering in long-day conditions and in continuous light. Moreover, cotyledons of mpk10 and mkk2 mutants have reduced vein complexity, which can be reversed by inhibiting polar auxin transport (PAT). Auxin does not affect AtMPKIO expression while treatment with the PAT inhibitor HFCA extends the expression in leaves and reverses the mpklO mutant phenotype. These results suggest that the AtMKK2-AtMPK10 MAPK module regulates venation complexity by altering PAT efficiency. 展开更多
关键词 Arabidopsis MAP kinase leaf development polar auxin transport leaf venation pattern.
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杉木人工林林分叶面积动态变化规律 被引量:3
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作者 屈彦成 江怡航 +2 位作者 陈涵玥 张建国 张雄清 《生态学报》 CAS CSCD 北大核心 2024年第13期5609-5620,共12页
叶面积与树木生长密切相关,是量化树木潜在生产能力的重要因子,其动态变化直接驱动林木生长的变化,但目前学者们对于林分叶面积动态变化规律却持有不同的观点。以亚热带不同气候区杉木人工林为研究对象,基于54个样地,共144株解析木的数... 叶面积与树木生长密切相关,是量化树木潜在生产能力的重要因子,其动态变化直接驱动林木生长的变化,但目前学者们对于林分叶面积动态变化规律却持有不同的观点。以亚热带不同气候区杉木人工林为研究对象,基于54个样地,共144株解析木的数据,采用6种生长方程通过非线性混合效应模型分别构建杉木单木叶面积模型和林分密度模型,将二者相乘得到林分叶面积动态变化模型,进而探究其动态变化规律。结果表明,以样地作为随机效应因子,考虑Logistic方程a参数上的随机效应,同时不考虑异方差结构的混合模型(样地水平)作为单木叶面积的最优模型;以地区作为随机效应因子,考虑Logistic方程a参数上的随机效应,同时不考虑异方差结构的混合模型(总体平均水平)作为林分密度的最优模型;林分叶面积动态变化呈单峰形式,幼龄阶段增长较快,达到峰值后迅速下降,之后下降幅度减少。本研究在考虑林分自然稀疏的前提下从生长模型的角度证明了杉木林分叶面积动态变化呈单峰型,而非达到顶峰后保持不变,同时也表明林分叶面积达到顶峰后下降是由于林分密度的降低引起的。研究结果对于合理经营不同气候梯度的杉木人工林具有重要意义。 展开更多
关键词 杉木 林分叶面积 动态变化 单峰 自然稀疏
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不同耕种模式对玉米叶片生理及结构的影响 被引量:1
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作者 程生煜 杨彩红 +1 位作者 崔文强 姜晓敏 《作物杂志》 北大核心 2024年第6期103-112,共10页
为探究河西灌溉农业区耕种模式对玉米叶片生理及结构的影响,设置免耕留茬(NT)与传统耕作(CT)2种耕作方式,小麦间作玉米(W/M)、小麦收后播种冬油菜玉米轮作(W-G→M)、小麦玉米轮作(W→M)3种种植模式,研究6个不同处理玉米叶片生理、结构... 为探究河西灌溉农业区耕种模式对玉米叶片生理及结构的影响,设置免耕留茬(NT)与传统耕作(CT)2种耕作方式,小麦间作玉米(W/M)、小麦收后播种冬油菜玉米轮作(W-G→M)、小麦玉米轮作(W→M)3种种植模式,研究6个不同处理玉米叶片生理、结构及产量变化。结果表明,NT模式下玉米可溶性糖含量有3个时期高于CT模式。灌浆期CT(W-G→M)与CT(W→M)处理可溶性糖含量显著低于其他处理。不同耕作处理的玉米叶片可溶性蛋白含量呈现出先增后减趋势,但不同耕作处理峰值出现时期有所不同。不同耕作处理叶片丙二醛(MDA)含量均呈先增后减趋势。成熟期W/M模式叶片比叶重(SLW)较W-G→M和W→M模式分别高23.75%和19.87%,NT(W/M)处理较其他处理高13.17%~39.66%。NT处理玉米叶片线粒体长轴近乎平行,内外膜和嵴清晰可见,而CT处理线粒体呈长条形且排列无序,弯曲盘旋于细胞内,多数呈堆积状存在于细胞内的一角,内外膜比较模糊。W/M模式中,NT小麦产量较CT高8.17%,NT玉米较CT平均增产13.91%,W/M模式玉米产量增幅最大。与传统耕作相比,免耕处理可提高玉米叶片可溶性糖含量、可溶性蛋白含量与SLW,增加叶片叶绿体数量,间作可减少叶片MDA含量,缓解叶片衰老。免耕玉米单株粒重、百粒重较传统耕作分别提高9.24%和9.40%,产量较传统耕作高13.91%。单株粒重、百粒重和玉米产量呈正相关关系。不同种植模式下,由于播种密度不同,小麦、玉米产量均低于轮作模式。麦玉间作土地当量比达到1.30~1.36。因此,玉米免耕间作模式是比较适合绿洲灌区推广应用的一种耕种模式。 展开更多
关键词 玉米 耕种模式 叶片生理 微结构 产量
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