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RL3(t),Responsible for Leaf Shape Formation,Delimited to a 46-kb DNA Fragment in Rice
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作者 GUO Min LI Rong-de +6 位作者 YAO Jian ZHU Juan FAN Xiang-yun WANG Wei TANG Shu-zhu GU Ming-hong YAN Chang-jie 《Rice science》 SCIE CSCD 2015年第1期44-48,共5页
Two mutants with rolled leaves, temporally designated as rl3(t)-I and rl3(t)-2, were served for exploring the mechanism underlying the rolled leaf characteristic. Except for having typical rolled leaves, the plant... Two mutants with rolled leaves, temporally designated as rl3(t)-I and rl3(t)-2, were served for exploring the mechanism underlying the rolled leaf characteristic. Except for having typical rolled leaves, the plant heights and panicle lengths of rl3(t)-1 and rl3(t)-2 significantly decreased, and the seed-setting rate also decreased when compared with wild type 93-11. Cytological analysis suggested that the rolled leaf phenotype might be caused by the changes of number and size of bulliform cells. Genetic analysis indicated rl3(t)-1 is allelic to rl3(t)-2, and controlled by a recessive gene. Gene mapping result indicated that RL3(t) gene resided in a 46-kb long region governed by the sequence tag site markers S3-39 and S3-36 on rice chromosome 3. The result provides an important clue for further cloning the RL3(t) and understanding the mechanism of rice leaf development. 展开更多
关键词 gene mapping leaf shape formation MUTANT RICE rolled leaf gene
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Analysis of QTLs for Flag Leaf Shape and Its Response to Elevated CO_2 in Rice(Oryza sativa)
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作者 FAN Gui-zhi DONG Yan-jun +5 位作者 WANG Chun-ming WAN Jian-min XIE Hui XU Chang-liang ZHU Jian-guo CAI Qing-sheng 《Rice science》 SCIE 2007年第1期7-12,共6页
To understand the responses of flag leaf shape in rice to elevated CO2 environment and their genetic characteristics, quantitative trait loci (QTLs) for flag leaf shape in rice were mapped onto the molecular marker ... To understand the responses of flag leaf shape in rice to elevated CO2 environment and their genetic characteristics, quantitative trait loci (QTLs) for flag leaf shape in rice were mapped onto the molecular marker linkage map of chromosome segment substitution lines (CSSLs) derived from a cross between a japonica variety Asominori and an indica variety IR24 under free air carbon dioxide enrichment (FACE, 200 μmol/mol above current levels) and current CO2 concentration (Ambient, about 370 μmol/mol). Three flag-leaf traits, flag-leaf length (LL), width (LW) and the ratio of LL to LW (RLW), were estimated for each CSSL and their parental varieties. The differences in LL, LW and RLW between parents and in LL and LW within IR24 between FACE and Ambient were significant at 1% level. The continuous distributions and transgressive segregations of LL, LW and RLW were also observed in CSSL population, showing that the three traits were quantitatively inherited under both FACE and Ambient. A total of 16 QTLs for the three traits were detected on chromosomes 1, 2, 3, 4, 6, 8 and 11 with LOD (Log10-1ikelihood ratio) scores ranging from 3.0 to 6.7. Among them, four QTLs (qLL-6*, qLL-8* qLW-4* and qRLW-6*) were commonly detected under both FACE and Ambient. Therefore, based on the different responses to elevated CO2 in comparison with current CO2 level, it can be suggested that the expressions of several QTLs associated with flag-leaf shape in rice could be induced by the high CO2 level. 展开更多
关键词 rice (Oryza sativa) flag leaf leaf shape character quantitative trait locus chromosome segment substitution lines carbon dioxide enrichment
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Scanning Electron Microscope Observation of Three Species on Pollen Grain Morphology and Leaf Epiderm Shape in Gramineae Triticeae 被引量:3
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作者 张珊珊 周印富 +4 位作者 林小虎 秦素平 张燕 张志雯 王秋涛 《Agricultural Science & Technology》 CAS 2009年第2期86-89,共4页
The pollen grain morphology and leaf epiderm shape and microstructural of Rye( Secale cereal ), common wheat and Octoploid Trititrigia were observed with the scanning electron microscope(SEM). The results revealed... The pollen grain morphology and leaf epiderm shape and microstructural of Rye( Secale cereal ), common wheat and Octoploid Trititrigia were observed with the scanning electron microscope(SEM). The results revealed that there were great differences between pollen and leaf epiderm microcosmic morphology in three species. Such characteristics of Octoploid tnticalwere between those of common wheat and Rye. The morphology of pollen grain and leaf epiderm shape counld be used as an index for taxonomy for genera and species, and had somewhat scientif- ic references to identify new multiploid species created by chromosome engineering. 展开更多
关键词 GRAMINEAE Pollen grain leaf epiderm shape SEM
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A crosstalk between auxin and brassinosteroid regulates leaf shape by modulating growth anisotropy 被引量:4
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作者 Yuanyuan Xiong Binbin Wu +8 位作者 Fei Du Xiaolu Guo Caihuan Tian Jinrong Hu Shouqin Lii Mian Long Lei Zhang Ying Wang Yuling Jiao 《Molecular Plant》 SCIE CAS CSCD 2021年第6期949-962,共14页
Leaf shape is highly variable within and among plant species,ranging from slender to oval shaped.This is largely determined by the proximodistal axis of growth.However,little is known about how proximal–distal growth... Leaf shape is highly variable within and among plant species,ranging from slender to oval shaped.This is largely determined by the proximodistal axis of growth.However,little is known about how proximal–distal growth is controlled to determine leaf shape.Here,we show that Arabidopsis leaf and sepal proximodistal growth is tuned by two phytohormones.Two class A AUXIN RESPONSE FACTORs(ARFs),ARF6 and ARF8,activate the transcription of DWARF4,which encodes a key brassinosteroid(BR)biosynthetic enzyme.At the cellular level,the phytohormones promote more directional cell expansion along the proximodistal axis,as well as final cell sizes.BRs promote the demethyl-esterification of cell wall pectins,leading to isotropic in-plane cell wall loosening.Notably,numerical simulation showed that isotropic cell wall loosening could lead to directional cell and organ growth along the proximodistal axis.Taken together,we show that auxin acts through biosynthesis of BRs to determine cell wall mechanics and directional cell growth to generate leaves of variable roundness. 展开更多
关键词 leaf shape proximodistal axis growth anisotropy mechanical signals AUXIN RESPONSE FACTOR BRASSINOSTEROIDS
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Leaf shape simulation of castor bean and its application in nondestructive leaf area estimation 被引量:2
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作者 Hailin Wei Xumeng Li +1 位作者 Ming Li Huang Huang 《International Journal of Agricultural and Biological Engineering》 SCIE EI CAS 2019年第4期135-140,共6页
The leaf shape and leaf area measurement are crucial in plant growth modeling.The castor bean leaf is large,palm-shaped with multiple clefts.The leaf shape simulation and leaf area estimation were less studied.The cir... The leaf shape and leaf area measurement are crucial in plant growth modeling.The castor bean leaf is large,palm-shaped with multiple clefts.The leaf shape simulation and leaf area estimation were less studied.The circular model and nonrectangular hyperbolic model were developed to describe the standard leaf shape of castor bean in this study,providing a model for simulating the leaf shape and a nondestructive way for estimating the leaf area respectively.In addition,a formula was established to estimate the leaf area by the parameter of the standard leaf shape of castor bean.Based on validation results,the circular model fits the landmarks and nonrectangular hyperbolic model fits the lobe margins very well.The leaf area was accurately estimated by using the established formula.This study could provide a theoretical reference for leaf visualization,a nondestructive and easy way to estimate the leaf area for other complex leaves with multiple lobes. 展开更多
关键词 leaf shape leaf area geometrical characteristics mathematical model image processing plant growth modeling
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Overexpressed BRH1, a RING finger gene, alters rosette leaf shape in Arabidopsis thaliana 被引量:9
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作者 Xiaoqian Wang Eryong Chen +6 位作者 Xiaoyang Ge Qian Gong HamamaIslam Butt Chaojun Zhang Zuoren Yang Fuguang Li Xueyan Zhang 《Science China(Life Sciences)》 SCIE CAS CSCD 2018年第1期79-87,共9页
Leaves are the most important plant parts for photosynthesis and respiration. Many genes are involved in determining leaf shape;however, little is known about the effects of brassinosteroid (BR) signaling-pathway gene... Leaves are the most important plant parts for photosynthesis and respiration. Many genes are involved in determining leaf shape;however, little is known about the effects of brassinosteroid (BR) signaling-pathway genes on the development of leaf shape. Here, the brassinosteroid-responsive RING-H2 (BRH1) gene, which is suppressed by 24-epi-brassinolide treatment, was isolated from Arabidopsis thaliana. The amino acid sequence contained a highly conserved RING finger domain. In a phylogenetic analysis,BRH1 clustered closely with GLYMA11G02470.1. The leaves of brh1 mutant plants were not much different to those of the wild-type, while transgenic plants with high BRH1 expression levels had rounder rosette leaves. Mutants of the BR synthesis pathway also had a similar round leaf phenotype, and greater BRH1 expression levels. Moreover, the related marker genes KNAT1,AtHB13 and ROT4, which are known to control leaf shape, altered transcriptional levels in both transgenic BRH1 and BR-synthesis mutant lines. Thus, BRH1 may be involved in the BR signaling pathway and regulate the growth and development of rosette leaves. Research on BRH1 may prove valuable for understanding the regulatory mechanism of leaf shape and improving the leaf shapes of ornamental plants. 展开更多
关键词 BRH1 RING finger leaf shape brassinosteroids
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Leaf Sequencing Algorithm Based on MLC Shape Constraint
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作者 景佳 裴曦 +2 位作者 汪冬 曹瑞芬 林辉 《Plasma Science and Technology》 SCIE EI CAS CSCD 2012年第6期563-566,共4页
Intensity modulated radiation therapy (IMRT) requires the determination of the appropriate multileaf collimator settings to deliver an intensity map. The purpose of this work was to attempt to regulate the shape bet... Intensity modulated radiation therapy (IMRT) requires the determination of the appropriate multileaf collimator settings to deliver an intensity map. The purpose of this work was to attempt to regulate the shape between adjacent multileaf collimator apertures by a leaf sequencing algorithm. To qualify and validate this algorithm, the integral test for the segment of the multileaf collimator of ARTS was performed with clinical intensity map experiments. By comparisons and analyses of the total number of monitor units and number of segments with benchmark results, the proposed algorithm performed well while the segment shape constraint produced segments with more compact shapes when delivering the planned intensity maps, which may help to reduce the multileaf collimator's specific effects. 展开更多
关键词 multileaf collimator leaf sequencing shape constraint
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Variation in Leaf Shapes of Nitraria Species and Effect on Leaf δ^(13)C
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作者 Li Yonghua Wu Bo +3 位作者 Lu Qi Jin Zhanhu Liu Dianjun Zhang Jinxin 《Chinese Forestry Science and Technology》 2012年第3期88-89,共2页
Leaf shapes are not only the useful indicators in plant taxonomy,but also the important factors affecting energy and material exchange in leaves.In this paper,we collected and scanned the leaves of Nitraria tangutorum... Leaf shapes are not only the useful indicators in plant taxonomy,but also the important factors affecting energy and material exchange in leaves.In this paper,we collected and scanned the leaves of Nitraria tangutorum in Dengkou of Inner Mongolia Autonomous Region(the mean annual precipitation 145 mm) and Minqin of Gansu Province (the mean annual precipitation 115 mm) and N. sphaerocarpa in Dunhuang,and then analyzed leaf shape parameters with Image - Pro Plus6.0 image processing software and leafδ<sup>13</sup>C values in the isotope laboratory of the Chinese Academy of Forestry.The result showed that:1) as leaf area increased with increasing water availability the increases in the leaf length and width were asynchronously;2) with the same leaf width,the 1 eaves of N.tangutorum and N.sphaerocarpa were significantly longer in high water available conditions;and 3) although there were significantly differences in water availability between Dengkou and Minqin,as well as between the bottom and middle of the alluvial fan near the East Lake in Dunhuang,the leafδ<sup>13</sup>C values of N.tangutorum or N.sphaerocarpa were similar in different water conditions(P】0.05).Our results suggested that the ratio of leaf perimeter to area would be an important factor which linked leaf shape to plant water physiology.During growing procedure of leaf area,leaf length increase was prior to its width to alleviate the reduction in ratio of perimeter to area and maintain water use efficiency of the plant. 展开更多
关键词 NITRARIA tangutorum NITRARIA sphaerocarpa leaf shape water AVAILABILITY leafδ13 C
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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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图像识别技术在杏品种资源叶片形态评估与多样性研究中的应用
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作者 王碧君 章秋平 +8 位作者 刘威生 刘硕 刘宁 张玉萍 张玉君 徐铭 马小雪 刘家成 赵海娟 《植物遗传资源学报》 北大核心 2025年第3期539-553,共15页
为了探讨杏叶片形态的遗传多样性,方便杏种质资源收集和品种识别,本研究以142份杏种质资源为材料,对杏叶片的28个表型性状进行了调查,基于图片识别技术对杏品种资源叶片形态特征进行快速评价。表型性状多样性分析结果表明,28个表型性状... 为了探讨杏叶片形态的遗传多样性,方便杏种质资源收集和品种识别,本研究以142份杏种质资源为材料,对杏叶片的28个表型性状进行了调查,基于图片识别技术对杏品种资源叶片形态特征进行快速评价。表型性状多样性分析结果表明,28个表型性状中13个质量性状和8个数量性状的变异系数均高于10%,表明142份杏品种资源的叶片表型存在丰富的遗传多样性。相关性分析发现叶片面积、叶片周长、叶片长度、叶片宽度4个性状间存在极显著的正相关;叶基形状、叶基角度与叶片长/宽呈极显著负相关;叶片圆度与叶尖长短呈显著负相关。主成分分析结果显示第1主成分由叶片大小相关性状组成;第2主成分为叶片颜色相关性状;第3和4主成分分别反映了叶片形状与叶片锯齿高度。根据聚类分析将杏种质资源大致划分为大叶-楔形类、小叶-浅绿类、大叶-深绿类、小叶-深绿类、小叶-圆形类、大叶-心形类、大叶-截形类和混杂类群等8个类群,第Ⅷ类群被分为6个亚群。本研究增加叶尖长短、叶缘锯齿深浅、叶片最宽处位置3个叶片质量性状作为识别不同杏品种的依据,对于今后我国杏种质资源的叶片形态评价与品种识别具有一定的参考价值。 展开更多
关键词 叶片形态 分级形状 数量性状 多样性
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Correlation between Leaf Size and Fruit Quality of Kiwi 被引量:9
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作者 金方伦 张发维 +2 位作者 岳宣 黎明 敖学熙 《Agricultural Science & Technology》 CAS 2016年第11期2469-2472,2488,共5页
[Objective] This study aimed to investigate the effect of leaf size on fruit quality of kiwi and relevant mechanism. [Method] The correlation between leaf shape and fruit quality of kiwi was studied during 2013-2015. ... [Objective] This study aimed to investigate the effect of leaf size on fruit quality of kiwi and relevant mechanism. [Method] The correlation between leaf shape and fruit quality of kiwi was studied during 2013-2015. [Result] The results of statistical analysis showed that the sing weight, longitudinal diameter, width, thickness, shape index and juice sugar content of fruit were 75.86±1.68 g, 73.284± 0.70 mm, 41.18±0.51 mm, 35.30±0.25 mm, 1.92±0.01 and (15.66±0.26)%, respec- tively; the length, width, shape index and area of leaf were 14.77±0.20 cm, 14.25± 0.16 cm, 0.94±0.09 and 152.39±3.26 cm^2, respectively; and the length and diameter of petiole were 11.03±0.25 cm and (31.50±0.79 mm)/10, respectively. The results of correlation analysis showed that the single fruit weight of kiwi was strongly positively related to fruit longitudinal diameter, fruit width, fruit thickness and leaf shape index, was significantly positively related to leaf length, was weakly positively related to petiole length, was positively related to leaf area, was weakly negatively related to leaf width and petiole diameter, and was negatively related to juice sugar content. The results of regression analysis showed that there was significant difference be- tween single fruit weight and juice sugar content (F=0.851 8, P〈0.01), instead of fruit longitudinal diameter (F=0.000 6, P〉0.05), fruit width (F=0.001 4, P〉0.05) and fruit thickness (F=0.005 4, P〉0.05); there was significant correlation between single fruit weight and leaf area (F=0.671 5, P〈0.01), instead of leaf length (F=0.139 3, P〉0.05), leaf width (F=0.358 5, P〉0.05) and leaf shape index (F=0.294 0, P〉0.05); there were significant correlations between juice sugar content and leaf length (F= 0.816 1, P〈0.01), leaf width (F=0.970 1, P〈0.01), leaf area (F=0.560 6, P〈0.01) and leaf shape index (F=0.885 1, P〈0.05). [Conclusion] Fruit single weight and oth- er quality properties could be predicted from leaf size, and leaf size can be used as the main basis for judging the quality of fruit. 展开更多
关键词 KIWI FRUIT Fruit quality leaf shape CORRELATION
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Effect of the L-D_(1)alleles on leaf morphology,canopy structure and photosynthetic productivity in upland cotton(Gossypium hirsutum L.) 被引量:1
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作者 JIANG Hui GAO Ming-wei +7 位作者 CHEN Ying ZHANG Chao WANG Jia-bao CHAI Qi-chao WANG Yong-cui ZHENG Jin-xiu WANG Xiu-li ZHAO Jun-sheng 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2023年第1期108-119,共12页
One of the most important objectives for breeders is to develop high-yield cultivars.The increase in crop yield has met with bottlenecks after the first green revolution,and more recent efforts have been focusing on a... One of the most important objectives for breeders is to develop high-yield cultivars.The increase in crop yield has met with bottlenecks after the first green revolution,and more recent efforts have been focusing on achieving high photosynthetic efficiency traits in order to enhance the yield.Leaf shape is a significant agronomic trait of upland cotton that affects plant and canopy architecture,yield,and other production attributes.The major leaf shape types,including normal,sub-okra,okra,and super-okra,with varying levels of lobe severity,are controlled by a multiple allelic series of the D-genome locus L-D_(1).To analyze the effects of L-D_(1)alleles on leaf morphology,photosynthetic related traits and yield of cotton,two sets of near isogenic lines(NILs)with different alleles were constructed in Lumianyan 22(LMY22)and Lumianyan 28(LMY28)backgrounds.The analysis of morphological parameters and the results of virus-induced gene silencing(VIGS)showed that the regulation of leaf shape by L-D_(1)alleles was similar to a gene-dosage effect.Compared with the normal leaf,deeper lobes of the sub-okra leaf improved plant canopy structure by decreasing the leaf area index(LAI)and increasing the light transmittance rate(LTR),and the mid-range LAI of sub-okra leaf also guaranteed the accumulation of cotton biomass.Although the chlorophyll content(SPAD)of sub-okra leaf was lower than those of the other two leaf shapes,the net photosynthetic rate(Pn)of sub-okra leaf was higher than those of okra leaf and normal leaf at most stages.Thus,the improvements in canopy structure,as well as photosynthetic and physiological characteristics,contributed to optimizing the light environment,thereby increasing the total biomass and yield in the lines with a sub-okra leaf shape.Our results suggest that the sub-okra leaf may have practical application in cultivating varieties,and could enhance sustainable and profitable cotton production. 展开更多
关键词 PHOTOSYNTHESIS canopy structure YIELD BIOMASS sub-okra leaf shape
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Comparision of the Leaf Morphology of Two Phoebe bournei Varieties
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作者 GUAN Hong-jiao SUN Bing +2 位作者 YANG Yu-jie HU Die FEI Yong-jun 《Agricultural Science & Technology》 CAS 2021年第2期38-44,共7页
To study the leaf variation and morphological diversity of Phoebe bournei,the leaves of two leaf types and one wild type in the same growth environment,which were marked as Type A,B,and C with wild type being marked a... To study the leaf variation and morphological diversity of Phoebe bournei,the leaves of two leaf types and one wild type in the same growth environment,which were marked as Type A,B,and C with wild type being marked as B,were used as testing materials.40 healthy mature leaves collected from healthy plants were taken as research samples and phenotypic characteristics,such as leaf shape,leaf length,leaf width,leaf area,and leaf vein were observed and analyzed.The leaves of Type A were oblanceolate,the base of the leaves was gradually narrow,and the tip of the leaves was gradually sharp.There were white pubescences on the back of the leaves,which were arranged in order.The pubescences were evenly distributed on the mesophyll and vein,in the same direction.The length,width,perimeter,and area of the leaves were smaller than those of the other two types.The leaves of Type B were narrow,oblanceolate,wedge-shaped at the base,long acuminate at the tip,with yellow brown villi on the back of the leaves,mainly distributed along the vein and the grid vein between the veins;the villi on the main veins were longer,and the villi between the mesophylls were less numerous and shorter.The length,perimeter,and aspect ratio of the blade were the largest of the three types and the whole blade was slender.Type C leaves were elliptical with a nearly truncated base and a sharp tip.There were white pubescences on the back of the leaves and less mesophyll pubescence along the veins.The length-width ratio of the blade was small,the width was large,and the whole blade was round.There were significant differences among the three leaf types of P.bournei and preliminary judgement was that Type A and Type C were spontaneous mutants. 展开更多
关键词 Phoebe bournei leaf shape Spontaneous mutants
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Leaf morphological variation among paper birch (<i>Betula papyrifera</i>Marsh.) genotypes across Canada 被引量:2
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作者 Anjala Pyakurel Jian R. Wang 《Open Journal of Ecology》 2013年第4期284-295,共12页
Variations in leaf morphological characteristics have been extensively studied at both interand intraspecific levels although not explicitly on paper birch (Betula papyrifera Marsh). Paper birch populations might have... Variations in leaf morphological characteristics have been extensively studied at both interand intraspecific levels although not explicitly on paper birch (Betula papyrifera Marsh). Paper birch populations might have considerable genotypic and leaf morphological variations that have allowed them to inhabit wide environmental gradients. In this study, we analyzed variations in leaf morphological characteristics in 23 paper birch populations collected across Canada and grown in a greenhouse. Furthermore, we examined whether the variations in leaf morphological characteristics observed were related to the climate of the population’s origin. We found significant genotypic differences in all leaf morphological characteristics (p < 0.05) measured among the birch populations. Thus, we expected that the morphological variations in birch might be related to natural diversity in birch populations due to environmental differences at habitat origin. Principal component analysis (PCA) reduced thirteen leaf morphological variables to five principal components (PC) explaining 84.74% of the total variance in the original data. PCs accumulated with specific leaf area, petiole and leaf width were positively related to latitudinal, longitudinal, and elevational gradients at the population’s origin. Unpredictably, these PCs were significantly negatively correlated to precipitation and aridity index at the origin. Thus, we analyzed if correlations within leaf morphological characteristics had supported the birch populations to acclimate and produce unpredictable relations with the environment of origin. Our results showed that the populations originated in limited precipitation (during growing season) had large leaf width and petiole size but low leaf hairs on adaxial surface. Thus, all these leaf morphological features provide a basis for the birch to reduce water loss from leaves and balance water use efficiency in reduced precipitation. Furthermore, the leaf characteristics measured may also include phenotypic plasticity of the birch as an acclimation to the environment as in the greenhouse. 展开更多
关键词 Morphological VARIATION leaf SIZE leaf shape PETIOLE SIZE leaf HAIRINESS Climatic Variables Paper Birch
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一株拟南芥宽叶形突变体atscamp的分离鉴定
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作者 郝雪峰 贾晓宇 +2 位作者 曹海艳 亢春霞 裴雁曦 《植物研究》 CAS CSCD 北大核心 2024年第2期232-238,共7页
叶片是主要的光合作用器官,选育利于光合作用的叶片形态已成为重要的育种目标。atscamp是从拟南芥(Arabidopsis thaliana)突变体库(约6000株系)中筛选获得的1株叶片宽大突变体。Tail-PCR分析该突变体为AT1G11180位点的插入,该基因位点编... 叶片是主要的光合作用器官,选育利于光合作用的叶片形态已成为重要的育种目标。atscamp是从拟南芥(Arabidopsis thaliana)突变体库(约6000株系)中筛选获得的1株叶片宽大突变体。Tail-PCR分析该突变体为AT1G11180位点的插入,该基因位点编码1个分泌载体膜蛋白(SCAMP)。RT-PCR检测显示,该基因转录表达水平基本为零。进一步研究发现,该突变体叶片的宽度和叶面积极显著大于野生型植株(P<0.01),但是冠幅基本保持不变;同时atscamp突变体叶绿素含量增加,叶绿素最大荧光、PSⅡ潜在光化学效率显著增加(P<0.05);相应地,突变体植株蒸腾系数(Tr)、净光合速率(Pn)和叶片水分利用效率(WUE)显著增加(P<0.05)。拟南芥AT1G11180基因的时空特异性表达分析显示,该基因仅在叶片中高表达,在其他器官中表达量很低;且随着植物发育成熟,该基因表达量逐渐增加。研究结果表明AtSCAMP基因在叶形发育中发挥着重要作用。 展开更多
关键词 拟南芥 AtSCAMP基因 叶形 突变体
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新型弧形板簧支撑非充气轮胎的有限元分析 被引量:2
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作者 翟子扬 邓小伟 余征跃 《橡胶工业》 CAS 2024年第8期616-623,共8页
设计一种以弧形等厚板簧为主要承载部件的新型非充气轮胎,建立其有限元模型,仿真模拟静态径向加载与稳态纯滚动工况,得出轮胎径向刚度和径向力,对接地压力参数进行评价,计算出轮胎有效滚动半径。结果表明:在静态径向加载条件下,轮胎径... 设计一种以弧形等厚板簧为主要承载部件的新型非充气轮胎,建立其有限元模型,仿真模拟静态径向加载与稳态纯滚动工况,得出轮胎径向刚度和径向力,对接地压力参数进行评价,计算出轮胎有效滚动半径。结果表明:在静态径向加载条件下,轮胎径向力与径向位移近似线性正相关,径向刚度和径向力随板簧厚度增大而增大;轮胎接地印痕中心出现应力集中现象,板簧越厚则平均接地压力越大,胎面不均匀磨损程度越高;轮胎有效滚动半径随径向负荷增大线性减小。本研究可为非充气轮胎性能分析或者结构优化提供参考。 展开更多
关键词 非充气轮胎 弧形板簧 径向刚度 接地压力 有效滚动半径 有限元分析
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修枝强度对刺槐林木生长、干形及花叶的影响 被引量:2
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作者 李一鸣 彭祚登 +3 位作者 解锡泽 王少明 孟淑霞 邢秀霞 《安徽农业大学学报》 CAS CSCD 2024年第1期44-55,共12页
为通过修枝科学高效地培育刺槐林并实现全面利用,以刺槐实生人工林为研究对象,通过修枝抚育措施,选取6种修枝强度进行随机区组试验,以生长指标、干形指标及花叶形态与生物量为监测指标,分析比较不同修枝强度下刺槐的响应。从生长指标来... 为通过修枝科学高效地培育刺槐林并实现全面利用,以刺槐实生人工林为研究对象,通过修枝抚育措施,选取6种修枝强度进行随机区组试验,以生长指标、干形指标及花叶形态与生物量为监测指标,分析比较不同修枝强度下刺槐的响应。从生长指标来看,刺槐林分平均胸径、平均材积在1/2修枝强度下生长更好且存在显著差异;修枝对平均树高、平均冠幅影响不大;随着修枝强度的增大,枝下高也随之增大。从干形指标来看,各修枝强度对尖削度无显著影响;形率上除常规修枝外,其他修枝强度均与对照相比有显著性差异;对高径比的分析表明,1/2修枝强度下干形更加细长,对照则更粗壮;随着修枝强度的增加,活冠高逐渐降低,对照与常规修枝二者存在显著差异。从单株叶数量与重量看,1/3修枝强度下收获最多。从刺槐复叶形态上看,不同修枝强度下的刺槐复叶长无显著差异,修枝强度对刺槐复叶宽与小叶长宽都有显著影响。单株花数量与重量则是对照收获最多。对于刺槐花的形态,不同修枝强度对花序长宽无显著影响,不同修枝强度下龙骨瓣、翼瓣、旗瓣与花萼在不同的花期会有不同的表现。刺槐林分对不同修枝强度的响应具有显著差异性,可通过修枝科学高效地培育刺槐林并实现全面利用。为实现能源林培育,1/2修枝强度下生长指标最好,且修下的枝同样可作为薪炭燃烧。为培育无节、饱满、通直的优质建筑材,采用1/2修枝强度对刺槐林生长、干形的促进效果最好。叶的生物量与形态指标对饲料林培育十分关键,以1/3修枝强度最佳;花的生物量与形态指标对蜜源林培育十分关键,以不修枝为宜。 展开更多
关键词 刺槐 修枝 生长 干形 花叶
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辣椒重组自交系群体果实和叶形性状的遗传分析
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作者 陈大青 戴云花 +3 位作者 毛莲珍 孙浩 周瑶 刘周斌 《中国蔬菜》 北大核心 2024年第2期38-45,共8页
通过朝天椒D71和甜椒D72组合构建辣椒重组自交系(recombiant inbred line,RIL),测定2种不同生长环境下RIL群体的单果质量、果长、果肩宽、果宽、果实硬度、果肉厚、果柄粗、叶宽和叶长共9个性状,分析其遗传规律。结果表明,多数性状在2... 通过朝天椒D71和甜椒D72组合构建辣椒重组自交系(recombiant inbred line,RIL),测定2种不同生长环境下RIL群体的单果质量、果长、果肩宽、果宽、果实硬度、果肉厚、果柄粗、叶宽和叶长共9个性状,分析其遗传规律。结果表明,多数性状在2种生长环境下的偏度系数和峰度系数的绝对值均小于1,表明这些性状具有典型的数量性状特征,说明群体各性状受多基因控制的影响。各性状变异系数平均值为16.73%~52.06%,其中单果质量的变异系数平均值最大,为52.06%,而叶长最小,仅为16.73%。群体性状遗传力范围为42.03%~51.21%,其中果实多个性状间均呈显著或极显著正相关,而果实硬度与其他性状呈显著或极显著负相关。在不同生长环境下,群体在E1下性状表现力要好于E2,变异现象分析说明该RIL群体内部有丰富的遗传变异,遗传力分析表明辣椒果实性状受到基因型和环境型共同作用的影响,且受环境型影响略高于基因型影响。RIL群体在2种生长环境下的各性状分布均呈正态分布或近似正态分布,这些性状属于典型的数量性状遗传。以上结果可为辣椒新品种的选育提供参考。 展开更多
关键词 辣椒 RIL群体 果实性状 叶形性状 遗传分析
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木棉树形结构和叶性状对生境要素的响应研究 被引量:1
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作者 毛开泽 高漫娟 +2 位作者 吴睿 张月萍 程希平 《广西植物》 CAS CSCD 北大核心 2024年第5期863-872,共10页
植物形态结构是植物本身与外部环境共同作用的结果。为了分析木棉树形结构与叶性状的相关关系,探索地形、土壤和气象要素对木棉生长的影响,以及揭示木棉的生长策略和适应机制,该文以云南省西双版纳国家级自然保护区内230棵木棉为研究对... 植物形态结构是植物本身与外部环境共同作用的结果。为了分析木棉树形结构与叶性状的相关关系,探索地形、土壤和气象要素对木棉生长的影响,以及揭示木棉的生长策略和适应机制,该文以云南省西双版纳国家级自然保护区内230棵木棉为研究对象,测定6个树形结构指标,8个叶性状指标以及所在区域地形、气象、土壤养分等生境要素,使用结构方程模型和变差分解分析各生境要素对木棉树形结构和叶性状的影响和解释度。结果表明:(1)木棉树形结构各观测指标之间、叶性状各观测指标之间存在相关性(P<0.05)。(2)生境要素各观测指标对木棉生长具有较强影响,其中年均降雨量、坡度、平均温度对木棉生长指标的解释率较高,是影响木棉生长的主要生境指标。(3)从标准化路径系数看,3个生境要素对木棉树形结构和叶性状影响具有一致性,均表现为地形要素>气象要素>土壤要素。(4)3个生境要素叠加解释了树形结构和叶性状分别为43.5%和12.3%,表现出树形结构对生境环境的响应大于叶性状对环境响应的特点。研究结果初步探明了木棉不同生长指标对环境要素的适应策略,为木棉在异质生境的培育、繁殖以及木棉人工林高效经营等提供了理论依据和实践参考。 展开更多
关键词 木棉 生境要素 树形结构 叶性状 冗余分析 结构方程模型
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基于插值法分析施肥量和留叶数对烤烟的影响 被引量:1
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作者 朱经伟 张恒 +9 位作者 刘青丽 彭友 刘艳霞 李寒 王新修 马亚欢 张燕 王红星 方正华 杨磊 《中国土壤与肥料》 CAS CSCD 北大核心 2024年第1期174-181,共8页
为明确烤烟适宜的施肥量和留叶数,提升烟叶生产过程中的综合效益,以施肥量和留叶数为变量,采用正交试验设计,通过插值的方法分析了不同施肥量、留叶数对烤烟农艺性状、经济性状、品质性状的影响。结果表明:随着施肥量由450 kg·hm^(... 为明确烤烟适宜的施肥量和留叶数,提升烟叶生产过程中的综合效益,以施肥量和留叶数为变量,采用正交试验设计,通过插值的方法分析了不同施肥量、留叶数对烤烟农艺性状、经济性状、品质性状的影响。结果表明:随着施肥量由450 kg·hm^(-2)增加至600 kg·hm^(-2),烤烟长势显著提升,产量、均价、中部和上部烟叶主要化学成分协调性评价总分逐渐提高;随着留叶数由每株16片增加至20片,成熟期最大叶面积与倒3叶面积差值逐渐增大,株形呈“倒塔形”-“筒形”-“塔形”变化。产量、产值分别提高20.8%、18.8%,上等烟率、均价分别降低7.6%、1.5%,烟叶种植净收益逐渐提高,中部和上部烟叶主要化学成分协调性评价总分均呈现先升高后降低的变化趋势。在烟叶生产过程中,适度提高养分供给强度,并增加留叶数,有利于提高烟叶品质,且烟农种植净收益较高。 展开更多
关键词 施肥量 留叶数 烤烟 株形 品质
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