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Comparative Antimicrobial Activities of the Gel, Leaf and Anthraquinone Fractionates of Four <i>Aloe</i>Species (<i>Aloe camperi</i>, <i>Aloe elegans</i>, <i>Aloe eumassawana</i>and <i>Aloe scholleri</i>) 预览
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作者 Lidia Biniam Medhin Danait Beraki Sibhatu +6 位作者 Mensura Seid Ferdos Mohammed Ferej Nuredin Mohamedkassm Yacob Berhane Atul Kaushek Mohammed Elfatih Humida Elmuaiz Gasmalbari 《微生物学(英文)》 2019年第2期139-150,共12页
This study aimed to determine the medicinal significance of traditionally used Aloe plants by testing their crude extracts and Anthraquinone fractionates for antimicrobial activity against standard stock organisms. Th... This study aimed to determine the medicinal significance of traditionally used Aloe plants by testing their crude extracts and Anthraquinone fractionates for antimicrobial activity against standard stock organisms. The significance of this study is to promote the discovery of new alternative to drugs currently being used. The gel and leaf cover of these four plants were extracted using cold ethanol extraction method and Anthraquinones were fractionated from the leaf cover using the liquid-liquid extraction technique. The extracts obtained were then screened in different concentrations for their antimicrobial activity against stock organisms Staphylococcus aureus (ATCC1 6538) and Escherchia coli (ATCC 25922) to access the activity of the aloe species against gram positive and gram negative bacteria. It was determined that the crude extracts of the gel and leaf part of the four aloe species had antimicrobial activity against gram positive (Staphylococcus aureus) and gram negative (Escherchia coli) bacteria and Escherchia coli showed the least sensitivity towards the four plant extracts while Staphylococcus aureus was highly susceptible. 展开更多
关键词 ALOE camperi ALOE ELEGANS ALOE eumassawana ALOE scholleri Antimicrobial Activity GEL LEAF Anthraquinones
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Adaptive Features of the Leaf of <i>Juno vicaria</i>(Vved.) T. Hall &Seisums in Different Ecological Conditions of Uzbekistan 预览
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作者 Nargiza K. Rakhimova Guljan M. Duschanova +3 位作者 Sodikjon Kh. Abdinazarov Eldor E. Temirov Sobitjon S. Nosirov Ismat N. Samadov 《美国植物学期刊(英文)》 2019年第6期947-957,共11页
The anatomical structure of the leaf of the Central Asian endemic species of Juno vicaria, growing in two different ecological conditions (Baysun Mountains of Surkhandary region and Tashkent Botanical Garden of Uzbeki... The anatomical structure of the leaf of the Central Asian endemic species of Juno vicaria, growing in two different ecological conditions (Baysun Mountains of Surkhandary region and Tashkent Botanical Garden of Uzbekistan) was analyzed and diagnostic signs were determined. Also identified are adaptive mesomorphic and xeromorphic signs from an environmental point of view. A species that grows in natural habitat is dominated by more xeromorphic signs: a thickened outer wall of the epidermis;numerous epidermal, spongy cells;submerged stomata;small, multi-row sclerenchymal and collenchymal cells, which indicate a more xeromorphic and adaptability, as well as the wide distribution of this species to the natural growing conditions. In a species growing under the conditions of introduction of the Tashkent Botanical Garden, more mesomorphic features predominate: thin-walled, large, few epidermal, spongy cells;not immersed stomata;large non multi-row sclerenchymal and collenchymal cells, which show that the species is adapted to altered habitat conditions. 展开更多
关键词 ANATOMY LEAF J. vicaria Surkhandarya Region Baysun Mountains Introduction Tashkent BOTANICAL Garden Uzbekistan
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Structural Features of the Leaf of Ephemeral Species of Representatives of the Brassicaceae Burnett Family in Southwestern Kyzylkum (Uzbekistan) 预览
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作者 Gulbakhor S. Tursinbaeva 《美国植物学期刊(英文)》 2019年第9期1631-1648,共18页
The results of a study conducted by light microscopy of the anatomical structure of the leaf in ephemeral species from the family Brassicaceae growing under the conditions of Kyzylkum (Uzbekistan) are presented. The f... The results of a study conducted by light microscopy of the anatomical structure of the leaf in ephemeral species from the family Brassicaceae growing under the conditions of Kyzylkum (Uzbekistan) are presented. The following diagnostic, structural adaptive features were revealed: a leaf lamellar, dentate (Diptychocarpus strictus), in Leptaleum filifolium—valky. It is pubescent with various types of trichomes: stellate, dendroid (Meniocus linifolius), equilateral (Streptoloma desertorum) and unequal (Strigosella, Leptaleum filifolium species), unicellular hooked (Leptaleum filifolium). Epidermal cells flattened with wavy or winding walls. The stomata are numerous, not submerged, anomocytic, hemiparacytic, anisocytic types are noted. In all species, the isolate-palisade type of leaf mesophyll predominates. Vascular bundles of all species are sclerified. The main protective features of the leaf of species of the family Brassicaceae are pubescence and sclerification of vascular bundles. We consider the mesomorphic and xeromorphic lines of development ancient and independent. Identified and described signs that can be used in taxonomy and ecology. 展开更多
关键词 ANATOMY LEAF EPHEMERAL Brassicaceae Kyzylkum Uzbekistan
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Physiological and genome-wide gene expression analyses of cold-induced leaf rolling at the seedling stage in rice (Oryza sativa L.) 预览
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作者 Jingfang Dong Junliang Zhao +6 位作者 Shaohong Zhang Tifeng Yang Qing Liu Xingxue Mao Hua Fu Wu Yang Bin Liu 《作物学报:英文版》 CAS CSCD 2019年第4期431-443,共13页
Leaf rolling and discoloration are two chilling-injury symptoms that are widely used as indicators for the evaluation of cold tolerance at the seedling stage in rice. However, the difference in cold-response mechanism... Leaf rolling and discoloration are two chilling-injury symptoms that are widely used as indicators for the evaluation of cold tolerance at the seedling stage in rice. However, the difference in cold-response mechanisms underlying these two traits remains unknown. In the present study, a cold-tolerant rice cultivar, Lijiangxintuanheigu, and a cold-sensitive cultivar, Sanhuangzhan-2, were subjected to low-temperature treatments and physiolog-ical and genome-wide gene expression analyses were conducted. Leaf rolling occurred at temperatures lower than 11℃, whereas discoloration appeared at moderately low temperatures such as 13℃. Chlorophyll contents in both cultivars were significantly decreased at 13℃, but not altered at 11℃. In contrast, the relative water content and relative electrolyte leakage of both cultivars decreased significantly at 11℃, but did not change at 13℃. Expression of genes associated with calcium signaling and abscisic acid (ABA) degradation was significantly altered at 11℃ in comparison with 25℃ and 13℃. Numerous genes in the DREB, MYB, bZIP, NAC, Zinc finger, bHLH, and WRKY gene families were differentially expressed. Many aquaporin genes and the key genes in trehalose and starch synthesis were down regulated at 11℃ in comparison with 25℃ and 13℃. These results suggest that the two chilling injury symptoms are temperature-specific and are controlled by different mechanisms. Cold-induced leaf rolling is associated with calcium and ABA signaling pathways and is regulated by multiple transcriptional regulators. The suppression of aquaporin genes and reduced accumulation of soluble sugars under cold stress results in a reduction in cellular water potential and consequently leaf rolling. 展开更多
关键词 Rice(Oryza sativa L.) Cold-induced LEAF yellowing Cold-induced LEAF rolling PHYSIOLOGICAL analysis GENOME-WIDE expression profiling
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Response of Platanus orientalis leaves to urban pollution by heavy metals 预览
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作者 Esmaiel Khosropour Pedram Attarod +4 位作者 Anoushirvan Shirvany Thomas Grant Pypker Vilma Bayramzadeh Leila Hakimi Mazaher Moeinaddini 《林业研究:英文版》 CAS CSCD 2019年第4期1437-1445,共9页
Atmospheric pollution is an important concern in urban environments.The impact of urban pollution on the physiological,biochemical and anatomical properties of leaves of oriental plane(Platanus orientalis L.)was studi... Atmospheric pollution is an important concern in urban environments.The impact of urban pollution on the physiological,biochemical and anatomical properties of leaves of oriental plane(Platanus orientalis L.)was studied.The leaves were collected from an urban site(Tehran,Iran)and a non-urban forest park(Chitgar Forest Park).Anatomical(stomata,parenchyma,and cuticle)and physiological(chlorophyll content,enzyme activities)properties were analyzed.The concentrations of Cd(cadmium),Pb(lead),Ni(nickel),and Cr(chromium)in leaves were significantly higher and Zn(zinc)lower at the urban site relative to the forest park.Chlorophyll a,total chlorophyll,and carotenoid content in leaves of the urban site were significantly less than those of the forest park,but there was no significant difference in chlorophyll b.In addition,the activities of superoxide dismutase,catalase,ascorbate peroxidase,and guaiacol peroxidase in urban leaves were significantly higher than in the leaves of the forest park.In the urban area,leaves experienced a significant decrease in leaf surface area,stomata density,stomata pore area,epidermis,and spongy mesophyll thickness,but a significant increase in cuticle and palisade thicknesses relative to forest park leaves.The increase in enzyme activities may indicate that the trees are attempting to cope with increased reactive oxygen species(ROS)because of pollution-induced stress.Our study suggests that oriental plane trees alter their physiological and anatomical properties when living in a polluted urban environment. 展开更多
关键词 Heavy metals LEAF ANATOMY LEAF PHYSIOLOGY ATMOSPHERIC pollution
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Family-level leaf nitrogen and phosphorus stoichiometry of global terrestrial plants
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作者 Di Tian Zhengbing Yan +11 位作者 Suhui Ma Yuehong Ding Yongkai Luo Yahan Chen Enzai Du Wenxuan Han Emoke Dalma Kovacs Haihua Shen Huifeng Hu Jens Kattge Bernhard Schmid Jingyun Fang 《中国科学:生命科学英文版》 SCIE CAS CSCD 2019年第8期1047-1057,共11页
Leaf nitrogen(N) and phosphorus(P) concentrations are critical for photosynthesis, growth, reproduction and other ecological processes of plants. Previous studies on large-scale biogeographic patterns of leaf N and P ... Leaf nitrogen(N) and phosphorus(P) concentrations are critical for photosynthesis, growth, reproduction and other ecological processes of plants. Previous studies on large-scale biogeographic patterns of leaf N and P stoichiometric relationships were mostly conducted using data pooled across taxa, while family/genus-level analyses are rarely reported. Here, we examined global patterns of family-specific leaf N and P stoichiometry using a global data set of 12,716 paired leaf N and P records which includes 204 families, 1,305 genera, and 3,420 species. After determining the minimum size of samples(i.e., 35 records), we analyzed leaf N and P concentrations, N:P ratios and N~P scaling relationships of plants for 62 families with 11,440 records. The numeric values of leaf N and P stoichiometry varied significantly across families and showed diverse trends along gradients of mean annual temperature(MAT) and mean annual precipitation(MAP). The leaf N and P concentrations and N:P ratios of 62 families ranged from 6.11 to 30.30 mg g–1, 0.27 to 2.17 mg g–1, and 10.20 to 35.40, respectively. Approximately 1/3–1/2 of the families(22–35 of 62) showed a decrease in leaf N and P concentrations and N:P ratios with increasing MAT or MAP, while the remainder either did not show a significant trend or presented the opposite pattern. Family-specific leaf N~P scaling exponents did not converge to a certain empirical value, with a range of 0.307–0.991 for 54 out of 62 families which indicated a significant N~P scaling relationship. Our results for the first time revealed large variation in the family-level leaf N and P stoichiometry of global terrestrial plants and that the stoichiometric relationships for at least one-third of the families were not consistent with the global trends reported previously. The numeric values of the family-specific leaf N and P stoichiometry documented in the current study provide critical synthetic parameters for biogeographic modeling and for further studies on the physiological and ecologica 展开更多
关键词 LEAF nitrogen (N) LEAF phosphorus (P) plant STOICHIOMETRY FAMILY N:P ratios N~P SCALING relationship climate
蝴蝶兰品种大辣椒叶片与花性状相关性研究 预览
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作者 宫子惠 李奥 +5 位作者 孙纪霞 张英杰 张京伟 郭文姣 房义福 刘学庆 《黑龙江农业科学》 2019年第4期76-80,共5页
为促进优质蝴蝶兰新品种培育,本研究以烟台市农业科学研究院兰花温室栽培的未开花蝴蝶兰品种大辣椒100株为试验材料,测量每株叶片生长与花朵品质的相关数据,探讨蝴蝶兰品种大辣椒叶片性状与花朵性状相关性的关系。将所有植株的6个叶片... 为促进优质蝴蝶兰新品种培育,本研究以烟台市农业科学研究院兰花温室栽培的未开花蝴蝶兰品种大辣椒100株为试验材料,测量每株叶片生长与花朵品质的相关数据,探讨蝴蝶兰品种大辣椒叶片性状与花朵性状相关性的关系。将所有植株的6个叶片性状和6个花朵性状进行分析,对叶片与叶片性状、叶片与花朵性状、叶面积与花朵性状分别进行相关性分析。结果表明:叶片与花朵性状有相关性影响,其中叶面积是影响花朵性状最重要的因素,尤其对花朵直径、花梗直径影响最显著。利用叶面积,可以预估蝴蝶兰品种大辣椒的花性状,进而判断其未来的开花品质。 展开更多
关键词 蝴蝶兰 叶片 花朵 叶面积 相关性
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Anatomical Structure of Vegetative and Generative Organs of <i>Silybum marianum</i>(L.) Gaertn. (Fam. Asteraceae) 预览
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作者 B. A. Nigmatullaev G. M. Duschanova +1 位作者 B. A. Abdurahmonov G. B. Sotimov 《美国植物学期刊(英文)》 2019年第1期38-43,共6页
The article provides information about the anatomical structure of the vegetative and generative organs grown in Tashkent conditions, and reveals the structural features: a mesomorphic leaf, a dorsi-central mesophyll ... The article provides information about the anatomical structure of the vegetative and generative organs grown in Tashkent conditions, and reveals the structural features: a mesomorphic leaf, a dorsi-central mesophyll type characteristic of dicotyledonous plants;stem beam type. A comparative analysis of the anatomical structure showed that the seed coat has a general plan of the structure with other members of the family Asteraceae. 展开更多
关键词 Silybum marianum Anatomical Structure Leaf Fruit Adaptation
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观赏海棠不同叶位色素组分动态研究 预览 被引量:1
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作者 姜文龙 李千惠 +2 位作者 周婷 江皓 张往祥 《中南林业科技大学学报》 CAS CSCD 北大核心 2019年第4期99-106,共8页
以57个观赏海棠品种为研究对象,对上位叶(Upper leaf)、中位叶(Middle leaf)、下位叶(Lower leaf)的色素组分进行测定,研究了海棠品种不同叶位间色素组分关系以及动态规律,为海棠优良观叶种质的筛选以及叶色改良提供理论参考。基于紫外... 以57个观赏海棠品种为研究对象,对上位叶(Upper leaf)、中位叶(Middle leaf)、下位叶(Lower leaf)的色素组分进行测定,研究了海棠品种不同叶位间色素组分关系以及动态规律,为海棠优良观叶种质的筛选以及叶色改良提供理论参考。基于紫外—可见分光光度计的色素绝对含量测定和基于Unispec-SC光谱分析仪的色素相对含量测定,分别构建了花青素(Anth)、类胡萝卜素(Car)、叶绿素(Chl)3大色素组分绝对含量与相对含量之间的拟合函数:yAnth=0.5221x^2-0.1114x+0.0133(R^2=0.9793);yCar=0.4562x+0.0726(R^2=0.9809);yChl=1.4287x-0.6726(R^2=0.9016)。采用Origin9.0软件构建了57个海棠品种的3大色素组分含量及权重的三维分布图。结果表明:1)基于紫外—可见分光光度计的色素绝对含量测定和基于Unispec-SC光谱分析仪的色素相对含量测定,分别构建了花青素(Anth)、类胡萝卜素(Car)、叶绿素(Chl)3大色素组分绝对含量与相对含量之间的拟合函数。2)基于上位叶叶绿素含量、花青素含量及其权重的聚类分析表明:57个海棠品种可分为2大色系4个子色系类群,即绿色系(含深绿色系、褐绿色系)、红色系(含紫红色系、红棕色系),各色系间差异显著。3)绿色系之A1子色系含有较低的花青素含量,且随着叶位的下降,其含量变化平稳,绿色呈现效果较好。4)A2子色系在上位叶阶段虽含有一定量的花青素,但不足以使叶片呈现出“全红”状态,因此绿色表达效果不如A1子色系。5)红色系之B1子色系的花青素含量及稳定性皆高于B2子色系,在上位叶、中位叶,B1子色系的花青素含量分别为B2子色系的2.1倍和2.6倍,显著提高了呈色效果。6)此外,在中位叶,B1子色系的花青素含量虽较上位叶有所淡化,但仍达到了B2子色系在上位叶的含量水平。 展开更多
关键词 海棠 叶片 叶位 色素组分 动态规律 江苏省扬州市
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玉米叶片水分利用效率的保守性 预览 被引量:1
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作者 周怀林 周广胜 《生态学报》 CAS CSCD 北大核心 2019年第6期2156-2167,共12页
水分利用效率是植物个体或生态系统水分利用过程的重要特征参数,可表征不同时空尺度的植物碳-水耦合关系,对植物适应气候变化研究具有重要意义。以玉米为例,利用中国气象局固城农业气象野外科学试验基地2013—2014年玉米不同灌溉方案模... 水分利用效率是植物个体或生态系统水分利用过程的重要特征参数,可表征不同时空尺度的植物碳-水耦合关系,对植物适应气候变化研究具有重要意义。以玉米为例,利用中国气象局固城农业气象野外科学试验基地2013—2014年玉米不同灌溉方案模拟试验资料,对不同叶位叶片的水分利用效率特征及其影响因素进行分析。结果表明:植株顶部第1片叶片水分利用效率在拔节期和乳熟期呈现明显的峰值,反映出明显的周期变化规律及其与叶片生理生态特征的紧密相关。在相同环境条件下,不同叶位叶片的水分利用效率不存在显著性差异,即玉米叶片水分利用效率具有空间稳定性与叶龄保守性。同时,研究指出叶片光合速率和蒸腾速率在叶位之间的协调变化是导致空间稳定性和叶龄保守性的主要原因。研究结果可为植物水分关系研究提供参考,也可为水分利用效率的尺度化研究提供依据。 展开更多
关键词 玉米 叶片 水分利用效率 叶位 保守性
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3种卫矛属植物叶片秋冬季转色期生理生化特征研究 预览 被引量:1
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作者 宋鹏 丁彦芬 +4 位作者 卓启苗 李涵 王亚楠 徐子涵 蔡慧 《西北植物学报》 CAS CSCD 北大核心 2019年第4期669-676,共8页
以疏花卫矛(Euonymus laxiflorus)、丝棉木(E.maackii)和卫矛(E.alatus)3种卫矛属植物为试验材料,测定叶片转色期叶色参数和相关生理生化指标,探讨各项指标的变化规律和内在联系,为优良色叶植物的筛选提供依据。结果表明:(1)转色期,疏... 以疏花卫矛(Euonymus laxiflorus)、丝棉木(E.maackii)和卫矛(E.alatus)3种卫矛属植物为试验材料,测定叶片转色期叶色参数和相关生理生化指标,探讨各项指标的变化规律和内在联系,为优良色叶植物的筛选提供依据。结果表明:(1)转色期,疏花卫矛的明亮度参数L^*和色素参数b^*(黄/蓝)呈上升趋势,色素参数a^*(红/绿)变化不大;丝棉木的L^*和b^*呈先上升后下降的单峰曲线,a^*呈上升趋势;卫矛的L^*和b^*变化不大,a^*呈上升趋势。(2)3种植物的叶绿素含量在转色期呈明显下降趋势;疏花卫矛的花色素苷相对含量、花色素苷/叶绿素的值较为平稳,类胡萝卜素/叶绿素的值呈上升趋势;丝棉木和卫矛的花色素苷相对含量、花色素苷/叶绿素的值均呈上升趋势,类胡萝卜素/叶绿素的值保持平稳。(3)3种植物苯丙氨酸解氨酶(PAL)活性呈下降趋势,查尔酮异构酶(CHI)活性呈先上升后下降的单峰曲线;卫矛的过氧化物酶(POD)和多酚氧化酶(PPO)活性保持平稳,疏花卫矛和丝棉木的POD活性呈上升趋势,疏花卫矛的PPO活性保持平稳,丝棉木的PPO活性呈下降趋势。(4)疏花卫矛和卫矛的可溶性糖和淀粉的质量分数呈先上升后下降的单峰曲线,丝棉木的可溶性糖和淀粉的质量分数呈上升趋势。(5)相关性分析显示,疏花卫矛呈现黄色主要是因为叶绿素的分解,丝棉木和卫矛呈现红色是因为花色素苷的合成,可溶性糖、淀粉、CHI对花色素苷的合成有一定作用,POD对叶片呈现红色有促进作用,PAL和PPO活性对花色素苷的合成无显著影响。 展开更多
关键词 卫矛属 转色期 叶片 叶色参数 生理生化指标
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科尔沁沙地两个菊芋品种叶片C、N、P化学计量特征 预览
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作者 高阳 高凯 +2 位作者 王琳 李天琦 赵力兴 《草原与草坪》 CAS CSCD 2019年第4期72-77,共6页
以不同生育期红皮和白皮菊芋叶片为研究对象,通过测定叶片中C、N、P含量,计算C/N,C/P和N/P比值,探讨菊芋叶片C、N、P化学计量特征动态变化规律。结果表明,随着生育期的进行,2种菊芋叶片中C含量和N含量都呈“降-升-降-升”的变化趋势,而... 以不同生育期红皮和白皮菊芋叶片为研究对象,通过测定叶片中C、N、P含量,计算C/N,C/P和N/P比值,探讨菊芋叶片C、N、P化学计量特征动态变化规律。结果表明,随着生育期的进行,2种菊芋叶片中C含量和N含量都呈“降-升-降-升”的变化趋势,而不同生育时期P含量红皮菊芋波动较小,白皮菊芋呈现“降-升-降-升”的趋势;C/N白皮菊芋为17.57~42.80,红皮菊芋为11.88~88.78;C/P白皮菊芋为442.40~1567.39,红皮菊芋为521.49~1243.72;N/P白皮菊芋为10.84~61.21,红皮菊芋为14.52~46.36;说明生长在科尔沁沙地的菊芋品种生长主要受P元素限制,在田间管理中应注意磷肥的施用。 展开更多
关键词 菊芋叶片 化学计量特征
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降香檀叶的非黄酮类成分研究 预览
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作者 吕玲 李威霆 谢海辉 《热带亚热带植物学报》 CAS CSCD 北大核心 2019年第2期213-218,共6页
为阐明降香檀(Dalbergia odorifera T. Chen)叶的化学成分,采用色谱分离方法,从叶的醇提和水煮液中得到8个非黄酮类化合物。经理化性质和波谱分析,分别鉴定为(3S)-6,7-二羟基-6,7-二氢芳樟醇(1)、淫羊藿次苷B1 (2)、淫羊藿次苷B6 (3)、... 为阐明降香檀(Dalbergia odorifera T. Chen)叶的化学成分,采用色谱分离方法,从叶的醇提和水煮液中得到8个非黄酮类化合物。经理化性质和波谱分析,分别鉴定为(3S)-6,7-二羟基-6,7-二氢芳樟醇(1)、淫羊藿次苷B1 (2)、淫羊藿次苷B6 (3)、淫羊藿次苷F2 (4)、苯甲醇β-巣菜糖苷(5)、苯乙醇β-巣菜糖苷(6)、2,3-丁二醇2-O-β-D-葡萄糖苷(7)和腺嘌呤(8)。化合物1为单萜、2和3为大柱香波龙烷糖苷、4~6为芳基糖苷、7为烷基糖苷、8为嘌呤,均为首次从该植物中报道。 展开更多
关键词 降香檀 非黄酮类成分 淫羊藿次苷 芳基糖苷
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28个八仙花品种叶片解剖结构与植株耐旱性的关系 预览 被引量:1
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作者 曾惠敏 赵冰 《东北林业大学学报》 CAS CSCD 北大核心 2019年第1期10-19,共10页
选取28个八仙花品种叶片的16项解剖结构指标进行观察,通过方差分析、相关分析、聚类分析和隶属函数法研究八仙花叶片解剖结构与其耐旱性的关系。结果表明:八仙花叶片为典型异面叶,上表皮细胞厚度均大于下表皮细胞厚度,气孔仅分布于叶片... 选取28个八仙花品种叶片的16项解剖结构指标进行观察,通过方差分析、相关分析、聚类分析和隶属函数法研究八仙花叶片解剖结构与其耐旱性的关系。结果表明:八仙花叶片为典型异面叶,上表皮细胞厚度均大于下表皮细胞厚度,气孔仅分布于叶片下表皮,呈椭圆形或近圆形。16项解剖结构的品种间差异均达到显著或极显著水平,将其聚为5类,通过相关分析筛选出五个影响植株耐旱性的主要指标为气孔密度、中脉厚度、下表皮长度、组织结构疏松度和栅栏组织/海棉组织(简称栅/海),再应用隶属函数值法对28个八仙花品种的耐早性进行排序,按平均隶属度将不同品种的耐旱性分为抗旱类型、中度抗旱类型、低抗旱类型和不抗旱类型四类。17号、19号、23号、25号和20号为抗旱类型;12号、18号和5号为中度抗旱类型;11号和24号为低抗旱类型;其余64.29%的品种均为不抗旱类型。 展开更多
关键词 八仙花 叶片 解剖结构 耐旱性 综合评价
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GC/MS法结合保留指数分析车前叶黄腺香青花茎叶挥发油的化学成分
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作者 张洪权 刘文琪 +4 位作者 肖长生 朱世明 张彬 郑平 吴田 《中药新药与临床药理》 CAS CSCD 北大核心 2019年第11期1379-1384,共6页
目的研究车前叶黄腺香青花、茎、叶挥发油的化学成分。方法采用同时蒸馏萃取法(SDE)提取车前叶黄腺香青花、茎、叶中的挥发油,使用气相色谱-质谱联用技术(GC-MS)获得总离子流图,各色谱峰相应的质谱图经过NIST11.L标准谱库检索,辅助保留... 目的研究车前叶黄腺香青花、茎、叶挥发油的化学成分。方法采用同时蒸馏萃取法(SDE)提取车前叶黄腺香青花、茎、叶中的挥发油,使用气相色谱-质谱联用技术(GC-MS)获得总离子流图,各色谱峰相应的质谱图经过NIST11.L标准谱库检索,辅助保留指数比对定性,并采用峰面积归一化法进行定量分析,计算各成分的相对百分含量。结果车前叶黄腺香青花、茎、叶挥发油中共鉴定出49种物质,相同成分有13种,花、茎、叶挥发油的化学成分含量差异较大,其中花挥发油中主要成分为(E)-石竹烯(35.11%)、α-葎草烯(13.40%)、γ-古芸烯(8.85%)、香叶基-α-松油烯(6.66%)、β-芹子烯(3.58%)等;茎挥发油中主要成分为(E)-石竹烯(14.89%)、α-葎草烯(9.50%)、β-依兰烯(5.94%)、香橙烯(5.47%)、(Z)-石竹烯(3.57%)等;叶挥发油中主要成分为(E)-石竹烯(16.06%)、α-葎草烯(8.00%)、γ-古芸烯(7.01%)、别香树烯(4.19%)、Ar-姜黄烯(4.05%)等。结论采用GC-MS法结合保留指数鉴别同分异构体,提高了车前叶黄腺香青花、茎、叶挥发油成分定性的准确性,为车前叶黄腺香青药用价值的开发和应用提供了参考。 展开更多
关键词 车前叶黄腺香青 花、茎、叶 挥发油 化学成分
外源褪黑素对NaCl胁迫下5BB葡萄叶片生理特性的影响 预览
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作者 韩国民 刘茜 +1 位作者 唐美玲 代玲敏 《浙江农业学报》 CSCD 北大核心 2019年第4期556-564,共9页
以砧木葡萄5BB (Vitis berlandieri×V.riparia 5BB)为材料,用离体叶片培养法进行NaCl胁迫。用3种不同浓度的褪黑素(melatonin,MT)溶液(100、200、500nmol·L^-1)分别与0.25mol·L^-1 NaCl溶液混合并将叶片叶柄浸入其中进... 以砧木葡萄5BB (Vitis berlandieri×V.riparia 5BB)为材料,用离体叶片培养法进行NaCl胁迫。用3种不同浓度的褪黑素(melatonin,MT)溶液(100、200、500nmol·L^-1)分别与0.25mol·L^-1 NaCl溶液混合并将叶片叶柄浸入其中进行培养,研究外源MT对NaCl胁迫下葡萄叶片光合作用和相关生理指标的影响。结果表明,NaCl胁迫下外源MT可有效增强超氧化物歧化酶(SOD)活性,及时清除逆境胁迫下叶片积累的氧自由基,减缓膜质过氧化过程,有效提高逆境胁迫下葡萄叶片中光合色素含量和光合能力。随着外源MT浓度的增加,对葡萄叶片的保护效果逐渐减小。外源MT能提高砧木葡萄5BB对NaCl胁迫的抵抗力,且浓度为100nmol·L^-1时效果较好。 展开更多
关键词 葡萄 叶片 外源褪黑素 NACL 胁迫 生理指标
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Seasonal variations of leaf traits and drought adaptation strategies of four common woody species in South Texas,USA 预览
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作者 Juan Qin Zhouping Shangguan Weimin Xi 《林业研究:英文版》 CAS CSCD 2019年第5期1715-1725,共11页
Understanding physiological responses and drought adaptation strategies of woody plant leaf traits in sub-humid to semi-arid regions is of vital importance to understand the interplay between ecological processes and ... Understanding physiological responses and drought adaptation strategies of woody plant leaf traits in sub-humid to semi-arid regions is of vital importance to understand the interplay between ecological processes and plant resource-allocation strategies of different tree species.Seasonal variations of leaf morphological traits,stoichiometric traits and their relationships of two drought tolerant woody species,live oak(Quercus virginiana)and honey mesquite(Prosopis glandulosa)and two less drought tolerant species,sugarberry(Celtis laevigata)and white ash(Fraxinus americana)were analyzed in a sub-humid to semi-arid area of south Texas,USA.Our findings demonstrate that for the two drought tolerant species,the leguminous P.glandulosa had the highest specific leaf area,leaf N,P,and lowest leaf area and dry mass,indicating that P.glandulosa adapts to an arid habitat by decreasing leaf area,thus reducing water loss,reflecting a resource acquisition strategy.While the evergreen species Q.virginiana exhibited higher leaf dry mass,leaf dry matter content,C content,C:N,C:P and N:P ratios,adapts to an arid habitat through increased leaf thickness and thus reduced water loss,reflecting a resource conservation strategy in south Texas.For the two less drought tolerant deciduous species,the variations of leaf traits in C.laevigata and F.americana varied between Q.virginiana and P.glandulosa,reflecting a trade-off between rapid plant growth and nutrient maintenance in a semi-arid environment. 展开更多
关键词 DROUGHT adaptation STRATEGIES Leaf TRAITS SEASONAL variations South Texas WOODY species
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拟南芥子叶与真叶差异基因的生物信息分析
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作者 陈健 侯昕 《分子植物育种》 CAS CSCD 北大核心 2019年第12期3894-3901,共8页
为研究拟南芥子叶与真叶的发育过程,本研究以模式植物拟南芥为研究材料,通过二代测序、富集分析等生物信息学的方法探索子叶与真叶基因表达的不同。在拟南芥真叶相较于子叶的差异基因分析中,共得到了 673个差异基因,其中上调的基因有570... 为研究拟南芥子叶与真叶的发育过程,本研究以模式植物拟南芥为研究材料,通过二代测序、富集分析等生物信息学的方法探索子叶与真叶基因表达的不同。在拟南芥真叶相较于子叶的差异基因分析中,共得到了 673个差异基因,其中上调的基因有570个,下调的基因有103个。进一步富集分析表明,拟南芥的真叶与子叶相比,真叶在光合作用以及细胞结构方面有大量差异基因富集,子叶则在糖原代谢以及一些次级代谢通路有大量差异基因富集。本研究结果为研究子叶特有的代谢通路提供了一定的理论基础。 展开更多
关键词 拟南芥 mRNA 生物信息
井冈山鹿角杜鹃群落灌木层植物叶功能性状对海拔梯度的响应 预览
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作者 向琳 陈芳清 +3 位作者 耿梦娅 王玉兵 吕坤 杨世林 《热带亚热带植物学报》 CAS CSCD 北大核心 2019年第2期129-138,共10页
为揭示鹿角杜鹃(Rhododendron latoucheae)群落灌木层植物叶功能性状及其对环境变化的响应趋势,对分布于井冈山不同海拔梯度鹿角杜鹃群落灌木层植物的叶功能性状进行了研究。结果表明,海拔梯度对灌木植物的叶功能性状有显著影响。随海... 为揭示鹿角杜鹃(Rhododendron latoucheae)群落灌木层植物叶功能性状及其对环境变化的响应趋势,对分布于井冈山不同海拔梯度鹿角杜鹃群落灌木层植物的叶功能性状进行了研究。结果表明,海拔梯度对灌木植物的叶功能性状有显著影响。随海拔的升高,叶片的干物质含量(LDMC)、厚度(LT)、氮含量(LNC)、磷含量(LPC)呈显著上升趋势,比叶面积(SLA)和N/P呈显著下降趋势,而叶大小(LS)呈先上升后下降的变化趋势;灌木植物叶片的LDMC与SLA、LS呈负相关,与LT、LNC、LPC呈正相关;SLA与LT、LNC呈负相关;LS与LT呈负相关;LNC与LPC呈正相关;N/P与LPC呈负相关;环境因子对灌木植物叶功能性状有重要影响,除受海拔的影响外,LPC、N/P还受坡位的影响,LS、LNC则分别还受到坡向和坡度的影响。因此,井冈山地区鹿角杜鹃群落灌木层植物通过改变叶功能性状来适应海拔和其它环境因子的变化。 展开更多
关键词 叶片 功能性状 海拔 干物质 鹿角杜鹃 井冈山
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福建寿宁野生茶树种质资源叶片和花粉微形态观察 预览
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作者 樊晓静 于文涛 +6 位作者 刘登勇 卢明基 郑洁 陈晓岚 魏明秀 林浥 叶乃兴 《福建农业学报》 CAS CSCD 北大核心 2019年第3期298-305,共8页
【目的】观察福建寿宁野生茶树种质资源叶片和花粉的微形态,为茶树野生种质资源发掘、鉴定提供参考依据。【方法】以福鼎大白茶为对照,利用冷场发射扫描电镜对4份福建寿宁野生茶树种质资源叶片和花粉微形态特征进行观察,对茶树叶片气孔... 【目的】观察福建寿宁野生茶树种质资源叶片和花粉的微形态,为茶树野生种质资源发掘、鉴定提供参考依据。【方法】以福鼎大白茶为对照,利用冷场发射扫描电镜对4份福建寿宁野生茶树种质资源叶片和花粉微形态特征进行观察,对茶树叶片气孔、茸毛和花粉极轴长、赤道轴长等进行数据统计及分析。【结果】4份野生茶树种质的叶片叶上表皮纹饰有平展型、皱脊型、波浪型3种;叶片下表皮气孔皆为长卵形,具异性气孔(腺鳞)且气孔密度相对栽培种较小;茸毛长度为(280.75±107.65)~(616.95±132.52)μm,且不同种长度差异明显,茸毛纹饰皆为平滑型;不同于栽培种,野生茶树种质资源叶片茸毛表层均有脱落现象。4份野生茶树花粉均具三孔沟,属N3P4C5类型,其花粉大小在(427.69±153.94)~(1205.07±237.80)μm^2,皆小于福鼎大白茶。花粉极面观有近圆形和三裂近三角形2种,赤道面观各不相同,花粉形状有超长球形和近球形2种,花粉纹饰均为疣状。【结论】4份野生茶树和福鼎大白茶的叶片和花粉微形态特征有一定的共性和特异性。 展开更多
关键词 野生茶树 种质资源 寿宁县 叶片 花粉 微形态
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