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北沙参花粉形态特征、活性及萌发条件研究 预览
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作者 韩晓伟 段小芳 +4 位作者 段伟萍 严玉平 刘钊 王乾 郑玉光 《种子》 北大核心 2019年第5期13-17,共5页
为了认识北沙参的花粉粒形态特征和生理特性,利用离体培养法测定花粉粒活性,并对培养条件(蔗糖的质量分数、硼酸的质量浓度和氯化钙的质量浓度)进行筛选,同时与碘-碘化钾(I2-KI)、氯化三苯基四氮唑(TTC法)和亚甲基蓝等花粉活性测定方法... 为了认识北沙参的花粉粒形态特征和生理特性,利用离体培养法测定花粉粒活性,并对培养条件(蔗糖的质量分数、硼酸的质量浓度和氯化钙的质量浓度)进行筛选,同时与碘-碘化钾(I2-KI)、氯化三苯基四氮唑(TTC法)和亚甲基蓝等花粉活性测定方法进行比较,建立测定北沙参花粉活性的最适宜方法,利用离体培养法进一步检测保存时间、温度和湿度等对北沙参花粉活性的影响,应用扫描电镜观察花粉粒的大小形态等特征。结果表明,亚甲基蓝法适于北沙参花粉粒活性测定,I2-KI法和TTC法不适合。北沙参体外萌发的最适培养基是20%蔗糖+0.1%mg·mL^-1硼酸+0.1%mg·mL^-1氯化钙,萌发率可达72.9%。北沙参花粉在湿度15%~52%,25℃条件下活性最好,4℃、-20℃的低温或大于60%的湿度都会导致花粉活性降低。北沙参花粉粒形态为超长方形,具3个狭长萌发沟,表面为网状。 展开更多
关键词 北沙参 花粉 电镜扫描 形态特征 花粉活性
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现代月季6个品种花粉超低温保存研究 预览
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作者 李泽迪 杜莹 +4 位作者 姜雪茹 鲁月秀 任瑞芬 张逸璇 刘燕 《西南农业学报》 CSCD 北大核心 2019年第6期1376-1382,共7页
【目的】为实现月季花粉长期保存,满足杂交育种和种质资源保存需要,本文以6个现代月季品种的花粉为试验材料,研究其超低温保存技术。【方法】用扫描电子显微镜观察比较6个品种花粉形态、干燥法测定花粉自然含水量、悬滴法检测花粉活力,... 【目的】为实现月季花粉长期保存,满足杂交育种和种质资源保存需要,本文以6个现代月季品种的花粉为试验材料,研究其超低温保存技术。【方法】用扫描电子显微镜观察比较6个品种花粉形态、干燥法测定花粉自然含水量、悬滴法检测花粉活力,筛选出适宜萌发培养液,在此基础上进行了液氮保存,并研究这些因素对超低温保存效果的影响。【结果】6个品种花粉悬滴培养的适宜萌发液为15%蔗糖+0.05%硼酸。不同品种新鲜花粉萌发率不同,春季采收的新鲜花粉萌发率为8.91%~27.07%,秋季为9.95%~24.32%,6个品种春季采集的花粉萌发率均高于秋季,但3个差异显著,3个差异不显著。不同品种新鲜花粉含水量不同,春季采收的花粉含水量为9.6%~11.9%;秋季为9.2%~11.5%,4个品种春、秋两季采收的花粉含水量没有显著差异,另外2个品种春季采收的花粉含水量分别显著高于或低于秋季花粉2.4%或1.6%,含水量变化值差异不大。超低温保存后花粉萌发率变化因品种和花粉采收季节而异,6个月季品种花粉经过液氮保存1个月后萌发率为10.36%~21.28%,为新鲜花粉的59.3%~133.9%。长球形的‘金凤凰’和‘希望’,超低温保存后花粉活力有所下降;而超长球形的‘金玛丽’、‘雨果’、‘伦特娜’和‘仙境’,超低温保存后萌发率基本保持稳定。花粉含水量与花粉超低温保存前后萌发率未显著相关。【结论】不同季节采收的自然成熟散粉的6个月季品种花粉均能实现超低温保存,秋季采收的花粉液氮保存后萌发率较新鲜花粉变化较小,但是春季采收的花粉萌发率更高,更适合超低温保存。超低温保存效果与品种、新鲜花粉萌发率、花粉形状和采收季节有关。 展开更多
关键词 现代月季品种 花粉 超低温保存 花粉形态
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In vivo interspecific pollination success between Pinus radiata,P.maximinoi,P.oocarpa and P.tecunumanii 预览
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作者 Hannel Ham Anna-Maria Botha +1 位作者 Arnulf Kanzler Ben du Toit 《林业研究:英文版》 CAS CSCD 2019年第3期817-826,共10页
The objective of the study was to investigate in vivo interspecific pollination success between Pinus radiata, P. maximinoi, P. oocarpa and P. tecunumanii. Pinus radiata was control pollinated with pollen lots of P. m... The objective of the study was to investigate in vivo interspecific pollination success between Pinus radiata, P. maximinoi, P. oocarpa and P. tecunumanii. Pinus radiata was control pollinated with pollen lots of P. maximinoi, P. oocarpa and P. tecunumanii in a P. radiata seed orchard at Karatara (Southern Cape, South Africa). Pollination success was determined by counting the number of visible ovules, pollen grains inside and outside P. radiata ovules, as well as pollen tubes visible inside P. radiata ovules. Conelets were harvested and studied at eight time intervals, including 24 h after pollination, and weekly for 7 weeks after pollination. Histology studies with a standard fixation-dehydration-embedding sequence and paraffin wax method were used to determine the number of visible pollen grains inside versus outside the ovules and number of pollen tubes. Results indicated that pollen grains did sift through the cone scales within 24 h after pollination. However, P. radiata differed significantly (time by type of cross interaction) from the other three hybrid combinations in terms of number of visible ovules, visible pollen grains inside and outside of the ovules as well as pollen tubes, confirming limited interspecific hybridisation success. Future studies need to determine the percentage of fertile ovules in cross combination as a tool in predicting pollination success. 展开更多
关键词 POLLEN tubes POLLEN grains Hybridization REPRODUCTIVE barriers PINUS RADIATA
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PUB7,a pollen expression gene induced by self-pollination,negatively regulates pollen germination
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作者 Xiaoping Lian Jing Zeng +4 位作者 Hecui Zhang Richard Converse Yukui Wang Xiaojing Bai Liquan Zhu 《生物化学与生物物理学报:英文版》 SCIE CAS CSCD 2019年第5期548-551,共4页
Self-incompatibility(SI)is a widespread reproductive mechanism that prevents inbreeding by rejecting self-pollination in plants.In Brassica,the recognition between pollen and stigma is highly specific,and requires spe... Self-incompatibility(SI)is a widespread reproductive mechanism that prevents inbreeding by rejecting self-pollination in plants.In Brassica,the recognition between pollen and stigma is highly specific,and requires species-specific protein interactions[1].Self-incompatibility is regulated by S-locus cysteine-rich protein(SCR),a stamen pollen response factor,which interacts with S-locus receptor kinase(SRK)and results in pollen rejection[2,3].Armadillo repeat containing 1 protein(ARC1)is a downstream component of SRK,which is located in the cytoplasm,and is phosphorylated by SRK.In the downstream signaling of self-pollination,ARC1 combines with Exo70A1 and forms a protein complex composed of ubiquitinated Exo70A1 complexed with ubiquitin-activating(E1)and ubiquitin-conjugating(E2)enzymes.Subsequently,a 26 S proteasome/COP9 signalosome triggers Exo70A1 degradation,leading to the inhibition of pollen germination in the stigma[4].PUB proteins belong to the U-box protein family,composed of a group of E3 ubiquitin ligases.Recent findings demonstrated that PUB proteins may be involved in stress responses,pathogen infection,signal transduction,cell cycle control,desensitization,circadian clock processes and self-incompatibility in plants[5–7]. 展开更多
关键词 a POLLEN EXPRESSION GENE SELF-POLLINATION POLLEN GERMINATION
花粉制剂治疗良性前列腺增生的研究进展
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作者 郭欣欣 孙崇智 李晓波 《国际生物医学工程杂志》 CAS 2019年第3期276-280,F0003共6页
良性前列腺增生(BPH)是中老年男性常见的泌尿系统疾病之一,严重影响着患者的健康和生活质量.目前BPH的发病机制尚未清楚,严重影响了BPH的有效治疗.近年来,越来越多的动物实验及临床试验结果表明,花粉制剂对BPH具有显著抑制作用.对BPH的... 良性前列腺增生(BPH)是中老年男性常见的泌尿系统疾病之一,严重影响着患者的健康和生活质量.目前BPH的发病机制尚未清楚,严重影响了BPH的有效治疗.近年来,越来越多的动物实验及临床试验结果表明,花粉制剂对BPH具有显著抑制作用.对BPH的发病机制和花粉制剂治疗BPH的相关研究进行综述,并分析花粉制剂的有效组分,使其在抗BPH方面的作用机制更加明确,最终达到全面利用的目的. 展开更多
关键词 花粉 植物制剂 良性前列腺增生 发病机制 作用机制
内蒙古自治区草原地区儿童变应性鼻炎流行病学调查
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作者 马婷婷 庄严 +15 位作者 石海云 宁惠宇 郭淼颖 何欢 康振祥 张铁军 张艳芬 雷彤 斯琴巴特 闫卫军 张芳芳 包秀芝 单广良 张彪 尹金淑 王学艳 《中华耳鼻咽喉头颈外科杂志》 CAS CSCD 北大核心 2019年第8期571-575,共5页
目的调查内蒙古自治区草原地区儿童变应性鼻炎(allergic rhinitis,AR)的自报患病率、临床特征、合并症以及室外花粉变应原的致敏情况.方法2015年5-8月期间采用多阶段、分层、随机、整群的方法调查内蒙古自治区草原6个地区的0~17岁儿童,... 目的调查内蒙古自治区草原地区儿童变应性鼻炎(allergic rhinitis,AR)的自报患病率、临床特征、合并症以及室外花粉变应原的致敏情况.方法2015年5-8月期间采用多阶段、分层、随机、整群的方法调查内蒙古自治区草原6个地区的0~17岁儿童,采用面对面问卷调查形式调查人群的一般情况、AR的主要临床症状及相关症状、合并疾病情况,同时进行10种草原变应原皮肤点刺试验(skin prick test,SPT)并监测该地区每天的花粉数量.应用SAS软件9.4进行数据处理.结果2443例儿童完成了问卷和SPT,儿童自报AR患病率为26.6%.男童患病率高于女童(28.8%比24.3%,χ^2=6.157,P<0.05);城市儿童的患病率高于农村(34.7%比18.8%,χ^2=79.107,P<0.05);6个地区AR患病率之间的差异有统计学意义(χ^2=221.416,P<0.05).儿童AR临床症状以喷嚏(88.2%)和鼻塞(78.6%)为主.AR合并支气管哮喘占16.5%(107/650),合并结膜炎占47.9%(311/650).AR症状高峰期主要出现在4月和7月,SPT显示主要变应原是蒿属和藜科花粉.结论内蒙古自治区草原地区儿童AR的患病率较高,喷嚏是儿童AR的主要临床症状,合并症中以结膜炎最多,夏秋季花粉暴露是引起AR的主要因素. 展开更多
关键词 鼻炎 变应性 儿童 患病率 临床症状 花粉
Cytological Observation of Pollen Abortion of Lycium barbarum Haploids from Anther Culture 预览
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作者 Qing LUO Bo ZHANG +2 位作者 Guoli DAI Jianhua ZHAO Youlong CAO 《药用植物研究(英文版)》 2019年第2期21-24,共4页
To reveal the sterility characteristics of Lycium barbarum haploids, cytological observations were made on the anthers of Ningqi No.1 and its haploids obtained from anther culture. The results showed that there were n... To reveal the sterility characteristics of Lycium barbarum haploids, cytological observations were made on the anthers of Ningqi No.1 and its haploids obtained from anther culture. The results showed that there were no significant differences in anther development between Ningqi No.1 and its haploids at the stage of pollen mother cell, and tetrads were formed successfully after the meiosis stage. The tetrads of Ningqi No.1 could release microspores. At the same time, the tapetal cells can provide nutrition for the development of the microspores, which eventually developed into mature pollen grains. Although the haploids could also release microspores at the tetrad stage, the tapetal cells degraded in advance, which made the released microspores unable to develop into mature pollen grains, resulting in pollen abortion of haploids. 展开更多
关键词 LYCIUM barbarum ANTHERS HAPLOIDS POLLEN ABORTION Cell morphology
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花楸花粉超低温保存及再生 预览
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作者 于琦 杨雨荷 +4 位作者 刘欢 郑昕雨 孔繁秋 张海莹 宋红 《福建农业学报》 CAS CSCD 北大核心 2019年第4期409-415,共7页
【目的】探讨花楸(Sorbus pohuashanensis)花粉超低温保存及再生的方法,以延长其花粉保存时间,为科研、生产提供理论和实践依据。【方法】分别设置不同培养基配方、不同光照、不同采集时间处理,进行花楸花粉离体萌发试验,测定各试验处... 【目的】探讨花楸(Sorbus pohuashanensis)花粉超低温保存及再生的方法,以延长其花粉保存时间,为科研、生产提供理论和实践依据。【方法】分别设置不同培养基配方、不同光照、不同采集时间处理,进行花楸花粉离体萌发试验,测定各试验处理的花粉萌发率;设置不同冷冻方式和化冻方式处理,测定两种方式不同处理的花粉萌发率;制备不同含水率的花粉,分别测定其在超低温保存前、后的萌发率。【结果】(1)培养基为100g·L^-1蔗糖+100 mg·L^-1硼酸的处理,花粉萌发率最高,达72.42%;(2)黑暗处理花粉萌发率为77.24%,比光照处理高8.96个百分点;(3)一天中,10∶00和14∶00采集的花粉,其活力显著高于其他时间采集的花粉;(4)-20℃预冷冻培养30min后投入液氮保存24h的处理效果最好,花粉萌发率达43.15%;(5)超低温保存后40℃水浴解冻5min处理比其他解冻方式处理的花粉活力高,萌发率为35.70%;(6)花楸花粉超低温保存最适含水率为7.72%,此含水率下花粉超低温保存后萌发率最高,为31.53%。【结论】花楸花粉采用超低温技术保存24h后仍具有活力,黑暗条件、花粉采集时间、花粉萌发培养基、花粉含水率、冷冻与化冻方式均会对花楸花粉超低温保存效果产生显著影响。 展开更多
关键词 花楸 花粉 超低温保存 种质资源保护
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植物微体化石分析揭示阿敦乔鲁遗址古人生存策略
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作者 邵孔兰 张健平 +3 位作者 丛德新 贾伟明 崔安宁 吴乃琴 《第四纪研究》 CAS CSCD 北大核心 2019年第1期37-47,共11页
新疆地区是史前游牧文化与农业文化交融的重要区域,而地处新疆西天山地区的阿敦乔鲁青铜时代遗址,是古代人类活动、文化发展与演化过程的重要时空节点。但是目前对该遗址古人生存策略,尤其是对于当时人们的饮食结构和遗址的季节性使用... 新疆地区是史前游牧文化与农业文化交融的重要区域,而地处新疆西天山地区的阿敦乔鲁青铜时代遗址,是古代人类活动、文化发展与演化过程的重要时空节点。但是目前对该遗址古人生存策略,尤其是对于当时人们的饮食结构和遗址的季节性使用的认识,存在不同观点。本研究通过对阿敦乔鲁遗址中房址内堆积物、羊粪化石以及遗址周边现代羊粪、自然地层进行植硅体、孢粉分析,发现了农作物植硅体以黍(Panicum miliaceum)和麦类作物的稃片为主,遗址使用后期出现少量的粟(Setaria italica),揭示了该遗址农作物组成以黍、大/小麦(Hordeum spp./Triticum spp.)为主,兼有粟的混合结构。在秋季(9月份)采集的现代羊粪中,孢粉种类(24个科/属)和浓度(平均65533粒/g)显著高于羊粪化石的孢粉种类(9个科/属)和浓度(平均27189粒/g),且现代羊粪以蒿属(Artemisia)植物(7~10月开花结籽)花粉为主(平均54.95%),羊粪化石中蒿属植物花粉仅有19.20%。来自早熟禾亚科(Pooideae)种子稃片的植硅体,在现代羊粪中的含量(平均3.62%)显著低于在羊粪化石中的含量(平均13.84%),羊粪孢粉和植硅体分析结果,揭示了阿敦乔鲁遗址羊类放牧时间应该处于花期结束后,植物已结籽的秋-冬季节,为阿敦乔鲁遗址冬季牧场的性质提供了植物学证据。同时房址内火塘、活动面和储藏间的堆积中植硅体组合与羊粪化石植硅体组合接近,暗示了羊粪可能被大量收集储藏,作为主要的铺垫物和冬季燃料使用。研究结果对于深化青铜时代以来新疆西天山地区古人生存策略、食物结构等的认识具有重要的推动作用。 展开更多
关键词 欧亚草原 农作物 植硅体 孢粉 粪化石 黍和粟
The complexity of climate reconstructions using the coexistence approach on Qinghai-Tibetan Plateau
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作者 Zhi-Yong Zhang Dong-Mei Cheng +3 位作者 Cheng-Sen Li Wan Hu Xuan-Huai Zhan Hong-Li Ji 《古地理学报:英文版》 CSCD 2019年第1期68-77,共10页
Quantifying the palaeoclimates of Qinghai–Tibetan Plateau is vital for understanding the uplift history of plateau and the evolution of Asian monsoon since Cenozoic. Recently, the Coexistence Approach(CA) has been em... Quantifying the palaeoclimates of Qinghai–Tibetan Plateau is vital for understanding the uplift history of plateau and the evolution of Asian monsoon since Cenozoic. Recently, the Coexistence Approach(CA) has been employed to reconstruct the palaeoelevation and palaeoclimate of the plateau by several studies. However, the application of CA in mountainous areas and the realism of climate reconstructions via this method are seldom discussed,although the complexity of reconstructions is speculated. Here we reevaluated the realism of climate reconstruction using the CA with modern pollen samples from the Qinghai–Tibetan Plateau, and try to explore the possible factors influencing the precipitation and temperature reconstructions by CA. We suggest that the long-distance transport pollen as a result of the Asian summer monsoon potentially significantly affects the reconstructions both for precipitation and temperature. The precipitation complexly interacting with snowmelt and permafrost thaw leads to the discrepancy between the reconstructed precipitation and the real value. The response temperature for blossoming of dwarfed plants on the plateau is mostly likely higher than the air temperature(usually measured at1.5 m above ground) due to energy flux or morphological adaptation of inflorescences during the growing season,causing the distortion of temperature reconstructions. Precipitation reconstruction is notoriously difficult as the establishers of CA have already suggested, but reconstructing the low temperatures may be even more challenging on Qinghai–Tibetan Plateau. Though all of the explorations in current paper are in a qualitative way, it offers an inspiration of how appropriately interpret the disagreements between CA results and the observations, and of how to obtain a reasonable reconstruction of palaeoclimate of the plateau. 展开更多
关键词 COMPLEXITY CLIMATE reconstruction COEXISTENCE approach Modern POLLEN ASSEMBLAGES Qinghai-Tibetan PLATEAU
Spatial patterns of vegetation and climate in the North China Plain during the Last Glacial Maximum and Holocene climatic optimum
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作者 Manyue LI Shengrui ZHANG +2 位作者 Qinghai XU Jule XIAO Ruilin WEN 《中国科学:地球科学英文版》 SCIE EI CAS CSCD 2019年第8期1279-1287,共9页
Reconstructing the spatial patterns of regional climate and vegetation during specific intervals in the past is important for assessing the possible responses of the ecological environment under future global warming ... Reconstructing the spatial patterns of regional climate and vegetation during specific intervals in the past is important for assessing the possible responses of the ecological environment under future global warming scenarios. In this study, we reconstructed the history of regional vegetation and climate based on six radiocarbon-dated pollen records from the North China Plain. Combining the results with existing pollen records, we reconstruct the paleoenvironment of the North China Plain during the Last Glacial Maximum(LGM) and the Holocene Climatic Optimum(HCO). The results show that changes in the regional vegetation since the LGM were primarily determined by climatic conditions, the geomorphic landscape and by human activity.During the LGM, the climate was cold and dry;mixed broadleaf-coniferous forest and deciduous-evergreen broadleaf forest developed in the southern mountains, and cold-resistant coniferous forest and mixed broadleaf-coniferous forest were present in the northern mountains. The forest cover was relatively low, with mesophytic and hygrophilous meadow occupying the southern part of the plain, and temperate grassland and desert steppe were distributed in the north;Chenopodiaceae-dominated halophytes grew on the exposed continental shelf of the Bohai Sea and Yellow Sea. During the HCO, the climate was warm and wet;deciduous broadleaf forest and deciduous-evergreen broadleaf forest, with subtropical species, developed in the southern mountains, and deciduous broadleaf forest with thermophilic species was present in northern mountains. Although the degree of forest cover was greater than during the LGM, the vegetation of the plain area was still dominated by herbs, while halophytes had migrated inland due to sea level rise. In addition, the expansion of human activities, especially the intensification of cultivation,had a significant influence on the natural vegetation. Our results provide data and a scientific basis for paleoclimate modelling and regional carbon cycle assessment in north China, w 展开更多
关键词 North China Plain Last GLACIAL Maximum HOLOCENE Climatic OPTIMUM POLLEN VEGETATION PALEOENVIRONMENT
大兴安岭北部满归泥炭孢粉重建的过去2100年古气候
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作者 李宜垠 李博闻 徐鑫 《第四纪研究》 CAS CSCD 北大核心 2019年第4期1034-1041,共8页
大兴安岭地处季风气候的尾闾区,是一个研究全球变化的关键区域.但由于该地区古气候代用指标(树轮、孢粉、石笋等)获取比较困难,历史文献也缺乏,使得古气候研究受到了限制.本研究通过大兴安岭北部的漠河县满归镇附近一个厚88 cm的泥炭剖... 大兴安岭地处季风气候的尾闾区,是一个研究全球变化的关键区域.但由于该地区古气候代用指标(树轮、孢粉、石笋等)获取比较困难,历史文献也缺乏,使得古气候研究受到了限制.本研究通过大兴安岭北部的漠河县满归镇附近一个厚88 cm的泥炭剖面的孢粉记录,根据831个表土样品的花粉数据和附近90个气象台站30年的地面观测数据,运用现代类比法( Modern Analogue Technique,简称MAT)重建了该地区过去2100年的年均温(Tann)、年降水量(Pann)、 1月均温(Tjan)和7月均温(Tjuly),结果表明Tann和Tjan的波动达到2. 4℃, Tjuly的波动为1. 7℃, Pann波动为28. 2 mm.该地区的气候变化分为3个阶段:阶段Ⅰ(150 BC~850 A.D.)温度和降水量相对较低,年均温比现代30年均值低约0. 5℃;阶段Ⅱ(850~1300 A.D.)以温度升高-降低的波动为特征,升温在1070~1170 A. D.期间最明显,年均温比现代 30 年平均值高 0. 2℃,这一时期相当于欧洲中世纪气候异常期( the Medieval Climate Anomaly,简称MCA);阶段Ⅲ(1300~2000 A.D.)早期(1300~1900 A.D.)以气温较低为特征,这一时期相当于小冰期(the Little Ice Age,简称LIA),年均温比现代30年平均值低0. 8℃,晚期(1900~2000 A.D.)呈现升温的趋势. 展开更多
关键词 孢粉 气候变化 中世纪气候异常期 小冰期 过去2千年 大兴安岭
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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叶面肥及生长调节剂对油茶雄蕊及坐果率的影响 预览
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作者 袁小军 钟秋平 +3 位作者 罗帅 曹林青 吴喜昌 郭和平 《西南林业大学学报》 CAS 北大核心 2019年第5期8-14,共7页
以7年生长林4#油茶为试材,采用正交试验设计方法,于盛花期前喷施不同浓度配比的叶面肥及生长调节剂,分析其对油茶雄蕊形态特征及坐果率的影响。结果表明:花期喷施叶面肥及生长调节剂对油茶花药形态特征及坐果率有显著影响。其中施用0.2 ... 以7年生长林4#油茶为试材,采用正交试验设计方法,于盛花期前喷施不同浓度配比的叶面肥及生长调节剂,分析其对油茶雄蕊形态特征及坐果率的影响。结果表明:花期喷施叶面肥及生长调节剂对油茶花药形态特征及坐果率有显著影响。其中施用0.2 g/L H3BO3+0.10 g/L KH2PO4+0.10 g/L 2,4-D最有利于花药的生长且对花粉表面纹饰影响最大,施用0.2 g/L H3BO3+0.05 g/L KH2PO4+0.20 g/L 2,4-D对极轴长/赤道轴长影响最大;施用0.15 g/L H3BO3+0.15 g/L KH2PO4+0.20 g/L 2,4-D对油茶坐果率的增幅最大,增幅达27.93%,坐果率为42.88%。可见,花期喷施一定浓度配比的叶面肥及生长调节剂对油茶雄蕊形态特征及坐果率有促进作用。 展开更多
关键词 油茶 叶面肥 生长调节剂 花药 花粉 坐果率
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车桑子小孢子发生与雄配子体发育 预览
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作者 卢雪佳 刘方炎 +1 位作者 高成杰 李昆 《热带亚热带植物学报》 CAS CSCD 北大核心 2019年第2期181-186,共6页
为了解干热河谷区车桑子(Dodonaea viscosa)胚胎学特征及其结籽率低的原因,采用常规石蜡切片法和电镜扫描技术对车桑子小孢子发生、雄配子体发育和花粉的形态特征进行了观察。结果表明,车桑子花药具有4个花粉囊。完整的花药壁从外到内... 为了解干热河谷区车桑子(Dodonaea viscosa)胚胎学特征及其结籽率低的原因,采用常规石蜡切片法和电镜扫描技术对车桑子小孢子发生、雄配子体发育和花粉的形态特征进行了观察。结果表明,车桑子花药具有4个花粉囊。完整的花药壁从外到内依次为表皮、药室内壁、2~3层中层细胞和绒毡层;绒毡层类型是腺质绒毡层。花药成熟期,中层、绒毡层均退化消失。小孢子母细胞进行同时型胞质分裂;四分体为四面体型结构。成熟的花粉为二细胞型。花粉近球形,外壁密布颗粒状纹饰,具有3条不构成合沟的萌发沟。雄性生殖发育过程出现的异常现象可能是干热河谷地区车桑子结籽率低的原因之一。 展开更多
关键词 车桑子 小孢子 雄配子体 花粉 形态特征
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常绿杜鹃不同杂种群间杂交的可育性分析
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作者 解玮佳 李世峰 +4 位作者 瞿素萍 彭绿春 张露 杨秀梅 王继华 《园艺学报》 CAS CSCD 北大核心 2019年第5期910-922,共13页
为研究杜鹃花属常绿杜鹃亚属中不同杂种群间杂交的可育性规律,对属于腺柱杜鹃花杂种群(Gr)、云锦杜鹃花杂种群(F)、美国山石南杜鹃花杂种群(Ga)、高加索杜鹃花杂种群(C)和东石楠杜鹃花杂种群(D)的33个品种组配302个杂交组合,对各杂种群... 为研究杜鹃花属常绿杜鹃亚属中不同杂种群间杂交的可育性规律,对属于腺柱杜鹃花杂种群(Gr)、云锦杜鹃花杂种群(F)、美国山石南杜鹃花杂种群(Ga)、高加索杜鹃花杂种群(C)和东石楠杜鹃花杂种群(D)的33个品种组配302个杂交组合,对各杂种群间的杂交坐果率、结籽率和种子发芽率进行统计分析;以Ga和F杂种群为父本的杂交组合的花粉萌发率、花粉管长度/花柱长度和胚珠受精率进行荧光显微观察。结果表明:(1)从坐果率考虑,在33个品种中,‘Blurettia’、‘Sun Fire’和‘Surrey Heath’等11个品种适宜作为母本,‘Mrs.P.Denouden’、‘Marcel Menard’和‘Catawbiensis Boursault’等5个品种适宜作为父本,‘Alfred’、‘Delta’和‘XXL’等16个品种作为母本或父本皆可,而‘Cosmopolitan’不适宜作亲本;在5个杂种群中,Gr适宜作为母本,F适宜作为父本,Ga作为母本或者父本皆可,C和D的杂交效果与其配组有关;不同杂种群间杂交存在单向不育、双向可育或不育现象。(2)5个杂种群作为母本杂交的坐果率、结籽率和种子发芽率大小则分别为Ga>Gr>C>D>F,Ga>C>Gr>D>F,Ga>C>F>G r>D;作为父本杂交的坐果率、结籽率和种子发芽率大小分别为F>Ga>Gr>D>C,F>Ga>D>C>Gr,F>Ga>Gr>C>D;作为亲本的坐果率、结籽率和种子发芽率大小分别为Ga>F>Gr>D>C,Ga>F>D>C>Gr,F>Ga>C>Gr>D。(3)从花粉荧光显微观察结果来看,除D×F的花粉不萌发外,其余组合的花粉均能萌发,但各杂交组合的花粉管长度/花柱长度不同,且胚珠受精率低下。综上所述:常绿杜鹃不同杂种群间杂交存在明显不育现象,包括不能坐果、不能结籽和种子不萌发,而受精前障碍和受精后障碍可能是其杂交不育的关键原因。 展开更多
关键词 常绿杜鹃 杂种群 杂交亲和性 结籽率 种子发芽率 花粉 荧光显微观察
Quantitative indicative significance of pollen assemblages on vegetation coverage in deciduous Quercus forest in the central Loess Plateau, China
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作者 Yuanhao SUN Shengrui ZHANG +5 位作者 Qinghai XU Yiwen LI Wei SHEN Tao WANG Zhongze ZHOU Ruchun ZHANG 《中国科学:地球科学英文版》 SCIE EI CAS CSCD 2019年第6期992-1001,共10页
We compared the pollen assemblages of surface moss samples and corresponding vegetation inventory data from 34 sites in the Huangling region of the central Loess Plateau. Our aims were to determine the characteristics... We compared the pollen assemblages of surface moss samples and corresponding vegetation inventory data from 34 sites in the Huangling region of the central Loess Plateau. Our aims were to determine the characteristics of the pollen assemblages from the deciduous broadleaved forest climax community and its significance in terms of vegetation type and species composition. The pollen assemblages are dominated by woody plants such as Quercus(42% of total terrestrial pollen),Betula(16%) and Pinus(12%), with minor differences between different plant communities. The pollen assemblages of individual sampling sites differed from the vegetation composition within the 0–100 m scope and were more similar to the vegetation coverage within the 0–1000 m scope. This indicates that the surface pollen assemblages mainly reflect the comprehensive information from the vegetation composition of a large area, rather than the vegetation composition close to the sampling site. The contents of Quercus, Betula and Pinus pollen are high, and close to their vegetation coverage;whereas the contents of deciduous broadleaved arbor taxa(such as Malus and Acer) are lower, but their corresponding regional vegetation cover is higher. This suggests that the vegetation information conveyed by poorly-represented pollen taxa should be considered when interpreting stratigraphic pollen assemblages. Using the observed quantitative relationships between pollen and vegetation of the main taxa, we reconstructed the regional vegetation composition in the Gonghai Lake area of the northeastern Loess Plateau during the middle Holocene(7300–5000 yr BP). The results indicated that Quercus-dominated deciduous broadleaved forest climax community developed in the mountains surrounding the lake. 展开更多
关键词 Loess Plateau DECIDUOUS broadleaved FOREST CLIMAX community POLLEN assemblage Absolute vegetation coverage
烟草花粉活力研究进展
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作者 许杰 潘磊 +3 位作者 杨帅 陈连红 耿世兵 马文广 《作物杂志》 CAS 北大核心 2019年第3期10-14,共5页
烟草不育系和杂交种的制种是世界烟叶生产发展的趋势。不育系和杂交种在制种过程中必须进行人工授粉,高活力的花粉带来高受精结实率和高的种子产质量,而烟草花粉的收集、贮藏和应用是烟草不育系和杂交种制种的关键技术环节。本文综述了... 烟草不育系和杂交种的制种是世界烟叶生产发展的趋势。不育系和杂交种在制种过程中必须进行人工授粉,高活力的花粉带来高受精结实率和高的种子产质量,而烟草花粉的收集、贮藏和应用是烟草不育系和杂交种制种的关键技术环节。本文综述了烟草花粉活力的检测方法、影响因素和烟草花粉的采集和贮藏技术研究进展,以期为烟草繁种生产提供参考依据。 展开更多
关键词 烟草 花粉 活力 贮藏
4个不同花色滇黄精品系花粉形态特征的电镜扫描分析 预览
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作者 董蓉娇 黄莉 +5 位作者 张雅琼 尹元萍 刘萍 王明君 王礼中 梁泉 《西南农业学报》 CSCD 北大核心 2019年第6期1236-1240,共5页
[目的]为滇黄精花粉形态学研究及进一步的分类和评价提供参考.[方法]选择4个不同花色的滇黄精品系,在植株形态比较的基础上,利用扫描电镜对花粉形状、外壁纹饰、极轴长(P)、赤道轴长等方面进行观察描述和比较.[结果]P1、P2和P3这3个品... [目的]为滇黄精花粉形态学研究及进一步的分类和评价提供参考.[方法]选择4个不同花色的滇黄精品系,在植株形态比较的基础上,利用扫描电镜对花粉形状、外壁纹饰、极轴长(P)、赤道轴长等方面进行观察描述和比较.[结果]P1、P2和P3这3个品系之间除了花色的差异,在多数植物学特征性状上没有显著差异,而P4具有植株较矮、叶片窄小、花被短小以及根茎呈圆柱状、其横切面黄色等特点;滇黄精花粉粒大,长球形,极面观为椭圆形或纺锤形,具远极单沟,沟缘整齐,沟膜较清晰,无萌发孔,外壁很薄,两层,外壁表面具细网状雕纹;4个品系的花粉大小及形态结构上差异不大,花粉长68~ 70 μm,极轴59~ 72 μm,赤道轴23~31 μm,极轴(P,μm)×赤道轴(E,μm)分别为65 μm × 25 μm、70μm×28 μm、64μm×26μm、66 μm×26μm,P/E为2.5~2.6.[结论]尽管4个滇黄精品系花色迥异,但在花粉大小及形态结构上差异不大,难以进行定性和定量的比较. 展开更多
关键词 滇黄精 植株形态 花粉 显微形态 电镜扫描
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Pollen Typhae Total Flavone Inhibits Endoplasmic Reticulum Stress-Induced Apoptosis in Human Aortic-Vascular Smooth Muscle Cells through Down-Regulating PERK-eIF2α-ATF4-CHOP Pathway
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作者 CHEN Ming-tai HUANG Ruo-lan +6 位作者 OU Li-jun CHEN Ying-nan MEN Ling CHANG Xiao WANG Ling YANG Yu-zhu ZHANG Zhong 《中国结合医学杂志:英文版》 SCIE CAS CSCD 2019年第8期604-612,共9页
Objective: To test the hypothesis that the inhibition of endoplasmic reticulum(ER) stress-induced apoptosis in oxidized low-density lipoproteins(ox-LDL)-induced human aortic-vascular smooth muscle cells(HA-VSMCs) was ... Objective: To test the hypothesis that the inhibition of endoplasmic reticulum(ER) stress-induced apoptosis in oxidized low-density lipoproteins(ox-LDL)-induced human aortic-vascular smooth muscle cells(HA-VSMCs) was associated with suppression of the protein kinase RNA-like ER kinase(PERK)-eukaryotic translation initiation factor 2α(e IF2α)-activating transcription factor 4(ATF4)-CCAAT/enhancer binding protein homologous protein(CHOP) signaling pathway by Pollen Typhae total flavone(PTF). Methods: Primary HA-VSMCs were cultured and identified. The cultured HA-VSMCs were randomized into 5 groups, including a normal control group, an ox-LDL group(70 μg/m L high ox-LDL), an HPTF group(70 μg/m L high ox-LDL+500 μg/m L PTF), an MPTF group(70 μg/m L high ox-LDL+250 μg/m L PTF), and a LPTF group(70 μg/m L high ox-LDL+100 μg/m L PTF) in the first part;and a normal control group, an ox-LDL group(70 μg/mL high ox-LDL), an MPTF group(70 μg/m L high ox-LDL+250 μg/m L PTF), a sh RNA group(transducted with PERK shRNA lentiviral particles), a scramble shRNA group(transducted with control shRNA lentiviral particles), an MPTF+ox-LDL+shRNA group(250 μg/mL PTF+70 μg/mL high ox-LDL+PERK shRNA lentiviral particles) and an ox-LDL+shRNA group(70 μg/mL high ox-LDL+PERK shRNA lentiviral particles) in the second part. The protein expression levels of ER-associated apoptosis proteins were detected by Western blot, and their m RNA expression levels were detected by quantitative real-time reverse transcription-polymerase chain reaction. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide(MTT) assay was applied to test cel viability, and the level of apoptosis was monitored by flow cytometry. Results: The MTT assay and flow cytometry showed that the ox-LDL group had a significant increase in apoptosis, which was attenuated in PTF treatment groups and sh RNA groups. Moreover, the ox-LDL group had increased protein and m RNA levels of binding immunoglobulin protein and ER-associated apoptosis proteins, such as PERK, 展开更多
关键词 Pollen Typhae total flavone endoplasmic reticulum stress PROTEIN KINASE RNA-like endoplasmic reticulum kinase-eukaryotic translation initiation FACTOR 2a -activating transcription FACTOR 4-CCAAT/enhancer binding PROTEIN homologous PROTEIN PATHWAY apoptosis vulnerable atherosclerotic plaque
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