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Nitrogen deposition as an important nutrient from the environment and its impact on ecosystems in China 被引量:15
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作者 Liu, XueJun Song, Ling +1 位作者 He, ChunE Zhang, FuSuo 《Journal of Arid Land》 SCIE 2010年第2期137-143,共7页
关键词 atmospheric deposition NITROGEN nutrient management ecological impacts
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基于高光谱遥感技术的不同小麦品种条锈病病情指数的反演 被引量:16
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作者 郭洁滨 黄冲 +2 位作者 王海光 孙振宇 马占鸿 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2009年第12期3353-3357,共5页
应用混合品种控制小麦条锈病在国内外日益受到重视,通过采集田间不同品种混合小麦条锈病各级病情梯度的高光谱遥感数据,将光谱数据与条锈病病情数据进行相关性分析,利用4个光谱参数构建其与病情指数的回归模型。结果表明,不同小麦品种... 应用混合品种控制小麦条锈病在国内外日益受到重视,通过采集田间不同品种混合小麦条锈病各级病情梯度的高光谱遥感数据,将光谱数据与条锈病病情数据进行相关性分析,利用4个光谱参数构建其与病情指数的回归模型。结果表明,不同小麦品种组合在不同的病情指数情况下,其冠层光谱信息都表现了一致的变化规律;冠层反射率在可见光区与病情指数为正相关,而在近红外区则达到了显著的负相关;利用690与850nm处的反射率、SDr、NDVI以及RVI与病情指数构建的回归模型拟合效果较好。研究表明利用高光谱反演条锈病病情指数是可行的,并且小麦不同品种对反演效果影响不大。 展开更多
关键词 高光谱 小麦条锈病 病情指数 反演模型
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DMSO作为氧化剂在有机合成中的应用 被引量:5
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作者 刘希光 吴景平 +1 位作者 梁晓梅 王道全 《有机化学》 SCIE CAS CSCD 北大核心 2001年第8期549-556,共8页
简要综述了二甲亚砜作为氧化剂的合成应用在最近十几年来的研究进展.
关键词 二甲亚砜 氧化剂 羰基化合物 有机合成 应用 DMSO 氧化 卤化物 氧化物 二硫化物 1 2-二酮
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Synthesis of linear and V-shaped oligo(phenylene ethynylene) derivatives:Geometric effects on photophysical properties
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作者 Yuan, Si Chun Han, Shu Liang +1 位作者 Ge, Xing Wang, Hui Chuan 《Chinese Chemical Letters》 SCIE CAS CSCD 2010年第1期97-100,共4页
关键词 Sonogashira coupling Oligo(phenylene ethynylene) derivatives Geometric effect Photophysical property
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Effects of sodium on nitrate uptake and osmotic adjustment of Suaeda physophora
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作者 Yuan, JunFeng Tian, ChangYan Feng, Gu 《Journal of Arid Land》 SCIE 2010年第3期190-196,共7页
Na+ ions play an important role in the growth of halophyte. The effect of Na+ ions on nitrate uptake and osmotic adjustment in the euhalophyte Suaeda physophora was investigated under glasshouse conditions. Seedlings ... Na+ ions play an important role in the growth of halophyte. The effect of Na+ ions on nitrate uptake and osmotic adjustment in the euhalophyte Suaeda physophora was investigated under glasshouse conditions. Seedlings were exposed to 1 mmol/L NaCl (control),300 mmol/L NaCl,150 mmol/L NaCl plus 150 mmol/L KCl or 300 mmol/L KCl treatments for 24 d. Dry weight was not affected greatly by different salt treatments,but water content and succulence in leaves of S. physophora were significantly increased at 300 mmol/L NaCl and 150 mmol/L NaCl plus 150 mmol/L KCl treatments. The concentrations of Na+ and NO3’ in leaves of S. physophora were the highest at 150 mmol/L NaCl plus 150 mmol/L KCl,but lowest at 300 mmol/L KCl treatment. Moreover,the increase of NO3’ concentration did not result in the decrease of Cl-concentration at 150 mmol/L NaCl plus 150 mmol/L KCl treatments. The estimated contribution of NO3’ to osmotic potential (CNO3) in leaves of S. physophora was 9.8% at 150 mmol/L NaCl plus 150 mmol/L KCl,and CNa and CCl were 31.0% and 23.3%,respectively. However,CNO3,CNa and CCl were respectively 1.6%,7.9% and 11.9% at 300 mmol/L KCl treatment. It is concluded that Na+ stimulates NO3’ absorption and the stimulation is independent on the internal or the external Cl-concentration in the euhalophyte S. physo-phora. These characteristics may explain the high levels of N in leaves of saline desert plants in arid ecosystem. 展开更多
关键词 euhalophyte Suaeda physophora NACL KCL NO3’
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A NEW. NEO-CLERODANE DITERPENE FROM AJUGA NIPPONENSIS
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作者 Liu, Z Li, ZQ +4 位作者 Zhang, CX Chen, RY Zhang, YG Qiu, YT Zhao, SH 《Chinese Chemical Letters》 SCIE CAS CSCD 1995年第7期581-582,共2页
ANEW.NEO-CLERODANEDITERPENEFROMAJUGANIPPONENSIS¥ZhunLIU,ZhongQinLI,ChunXingZHANG,RuYuCHEN(TheInstituteofElem... ANEW.NEO-CLERODANEDITERPENEFROMAJUGANIPPONENSIS¥ZhunLIU,ZhongQinLI,ChunXingZHANG,RuYuCHEN(TheInstituteofElemento-organicChemi... 展开更多
关键词 NEO-CLERODANE DITERPENE FROM AJUGA NIPPONENSIS A NEW
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FINITE-PART INTEGRAL AND BOUNDARY ELEMENT METHOD FOR INTERACTION BETWEEN TWO PARALLEL PLANAR CRACKS IN THREE-DIMENSIONAL FINITE BODIES
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作者 Wang Aiqin Qin Taiyan 《Acta Mechanica Solida Sinica》 SCIE EI 1998年第2期95-103,共9页
By using the Somigliana representation and the concepts offinite-part integrals, a set of hypersingular integral equations ofthe interaction between two parallel planar cracks in a three-dimen-sional finite body subje... By using the Somigliana representation and the concepts offinite-part integrals, a set of hypersingular integral equations ofthe interaction between two parallel planar cracks in a three-dimen-sional finite body subjected to arbitrary loads is derived, and thenits numerical method is proposed by the finite-part integral methodcombined with the boundary element method. According to the analytictheory of hypersingular integral equations, the square root models ofdisplacement discontinuities in the elements near the crack front areapplied, and thus the computational precision is raised. Based onthis, the stress intensity factors can be directly calculated.Finally, the stress intensity factors of sever- al typicalinteraction problems are calculated. 展开更多
关键词 two parallel planar craclks three-dimensional finite body hypersingularintegral
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Identification and mapping of genes for improving yield from Chinese common wild rice (O.rufipogon Griff.) using advanced backcross QTL analysis 被引量:39
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作者 Dejun Li Chuanqing Sun +5 位作者 Yongcai Fu Cheng Li Zuofeng Zhu Liang Chen Hongwei Cai Xiangkun Wang 《Chinese Science Bulletin》 SCIE EI CAS 2002年第18期1533-1537,共5页
To identify useful genes from wild rice which have been lost or weakened in cultivated rice has become more and more important for modern breeding strategy. In this study, a BC4 population derived from 94W1, an access... To identify useful genes from wild rice which have been lost or weakened in cultivated rice has become more and more important for modern breeding strategy. In this study, a BC4 population derived from 94W1, an accession of common wild rice (Oryza rufipogon Griff.) from Dongxiang in Jiangxi Province of China, as the donor, and a high-yielding Indica cultivar (O. sativa L.), 'Guichao 2', as the recipient, was used to identify quantitative trait loci (QTL) associated with yield and its components. Based on the analysis for the genotype of BC4F1 population with 87 SSR markers distributed throughout the genome and investigation of the plant height, yield and yield components of BC4F2, a total of 52 QTLs, were detected. Of 7 QTLs associated with grain yield per plant, 2 QTLs on chromosome 2 and chromosome 11 for grain yield, explaining 16% and 11% of the phenotypic variance respectively, were identified. The alleles from Dongxiang common wild rice in those two loci could increase the yield of 'Guichao 2' by 展开更多
关键词 COMMON WILD rice YIELD YIELD components MAPPING AB-QTL.
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New advances in virtual plant research 被引量:21
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作者 Yan Guo Baoguo Li 《Chinese Science Bulletin》 SCIE EI CAS 2001年第11期888-894,共7页
Virtual plants are computer simulations of the growth, development and deployment of plants in a three-dimensional space. Over the past 20 years, significant progress has been made in virtual plant modeling correspond... Virtual plants are computer simulations of the growth, development and deployment of plants in a three-dimensional space. Over the past 20 years, significant progress has been made in virtual plant modeling corresponding to the rapid advances in information technology. Virtual plant research has broad applications in agronomy, forestry, ecology, and remote sensing areas. In this review, we attempt to introduce the significance, modeling methodology, and main advances in virtual plant research and applications. The challenges associated with virtual plant modeling in agronomy applications, including the interaction mechanism between plant and environment and root system modeling, are also discussed. Insights into applications of virtual plants in agronomy are given in the areas of performing virtual experiments to accurately quantify the utilization of soil water and nutrients, to design crop ideotype on computers, and to improve crop planting. 展开更多
关键词 VIRTUAL PLANT PLANT architecture THREE-DIMENSIONAL digi- tizing VISUALIZATION VIRTUAL experiment.
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Production of transgenic blastocyst of sheep by somatic cell cloning 被引量:13
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作者 Xiaorong An Kemian Gou Yongfu Chen 《Chinese Science Bulletin》 SCIE EI CAS 2001年第19期1630-1634,1674,共6页
Five samples from primary cultures of five sheep ovarian granulosa cells were transfected by pEGFP-N1 DNA. Five transgenic positive cell lines, each from one of the five samples above, were used as donor nuclei for so... Five samples from primary cultures of five sheep ovarian granulosa cells were transfected by pEGFP-N1 DNA. Five transgenic positive cell lines, each from one of the five samples above, were used as donor nuclei for somatic nucleus transfer. A total of 352 in vitro matured and enucleated sheep oocytes were fused electrically with transgenic granulosa cells and 329 reconstructed embryos were obtained after activation by Ionomycin/6-DMAP, and these embryos were cultured in SOFaaBSA medium for 7 d. The result shows that 312 embryos (94.8%) had gone through cleavage and among them 63 (19.1%) had developed to the blastocyst stage. Expression of GFP gene was detected in various stages of early embryonic development by sampling randomly. Blastocyst rates given by the four cells treated with 0.5% FCS starvation was 19.6% (55/280) and it had notshown difference significantly (P】0.05) with the result obtained with another cell line that had not gone through serum starvation (16.3%, 8/49). This experiment 展开更多
关键词 SHEEP GRANULOSA cell NUCLEUS TRANSFER TRANSGENIC blastocyst.
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Identification of a senescence-related protease in coriander leaves 被引量:10
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作者 Weibo Jiang Xiangjuan Zhou +1 位作者 Yumei Zhao Pengcheng Liu 《Chinese Science Bulletin》 SCIE EI CAS 2002年第13期1096-1099,共4页
Senescence-related protease may play an important role in leaf senescence. By improved SDS-Gela-tin-PAGE assay, a 63 ku senescence-related protease (63 SRP) in coriander leaves was identified. Activity of 63 SRP was i... Senescence-related protease may play an important role in leaf senescence. By improved SDS-Gela-tin-PAGE assay, a 63 ku senescence-related protease (63 SRP) in coriander leaves was identified. Activity of 63 SRP was increased in parallel to the advance of coriander leaf senescence, and inhibited by treating the leaf with gibberellic acid, and enhanced by ethylene treatment. The 63 SRP was suggested to be a serine protease based on the fact that its activity was inhibited by the protease inhibitor PMSF. The optimal temperature for the activity of the 70 ku protease was 50°C. The maximal activity was observed at pH 6-9, some activity could be observed on the gel slices incubated at pH 5 or 11. The 63 SRP was partly purified by the way of ammonium sulfate precipitation and then gel slicing after gel elec-trophoresis. 展开更多
关键词 CORIANDER LEAF SENESCENCE PROTEASE protein degradation.
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Relative efficiency of marker assisted selection when marker and QTL are incom-pletely linked 被引量:11
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作者 Liu Huiying Zhang Qin Zhang Yuan 《Chinese Science Bulletin》 SCIE EI CAS 2001年第24期2058-2063,共6页
The relative superiority in selection response of two basic marker-assisted selection strategies, marker-assisted BLUP (MBLUP) and two-stage selection, in comparison to standard BLUP was investigated using stochastic ... The relative superiority in selection response of two basic marker-assisted selection strategies, marker-assisted BLUP (MBLUP) and two-stage selection, in comparison to standard BLUP was investigated using stochastic simulation of a closed nucleus herd. In marker-assisted BLUP the marker information and the phenotypic information were utilized simultaneously for selecting parental animals, whereas in two-stage selection they were utilized separately in two stages. Different heritabilities and QTL sizes were considered in the simulation. The QTL was assumed to be referred only via flanking markers, which were incompletely linked to the QTL. It was shown that both MBLUP and two-stage selection increased the QTL response but decreased the polygenic response. When the heritability was low or the QTL effect was large MBLUP was superior to standard BLUP by up to 5% with respect to total genetic response. While the two-stage selection did not show any superiority although it gave extremely large increase in 展开更多
关键词 marker-assisted BLUP TWO-STAGE SELECTION simulation.
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A global compact result for a semilinear elliptic problem with Hardy potential and critical nonlinearities on R^N 被引量:6
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作者 Jin LingYu Deng YinBin 《Science China Mathematics》 SCIE 2010年第2期385-400,共16页
In this paper, we are concerned with the following class of elliptic problems:where 2 = 2N/(N-2) is the critical Sobolev exponent, 2 < q < 2 , 0≤μ < μˉ=(N-2)2_4 , a(x), k(x) ∈ C(RN ). Through a compactne... In this paper, we are concerned with the following class of elliptic problems:where 2 = 2N/(N-2) is the critical Sobolev exponent, 2 < q < 2 , 0≤μ < μˉ=(N-2)2_4 , a(x), k(x) ∈ C(RN ). Through a compactness analysis of the functional corresponding to the problems , we obtain the existence of positive solutions for this problem under certain assumptions on a(x) and k(x). 展开更多
关键词 ELLIPTIC equation COMPACTNESS positive solution UNBOUNDED domain
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Muscarinic acetylcholine receptor is involved in acetylcholine regulating stomatal movement 被引量:3
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作者 Hengbin Wang Xuechen Wang +1 位作者 Shuqiu Zhang Chenghou Lou 《Chinese Science Bulletin》 SCIE EI CAS 2000年第3期250-252,共3页
In animal cells, action of acetylcholine depends on its binding with its two specific receptors on the plasma membrane: the nicotinic and muscarinic respectively. The present investigation has shown that agonists of m... In animal cells, action of acetylcholine depends on its binding with its two specific receptors on the plasma membrane: the nicotinic and muscarinic respectively. The present investigation has shown that agonists of muscarinic receptor (muscarine) could induce stomatal opening, while the antagonists (atropine) could block stomatal opening induced by acetylcholine. Their effects can only be realized in medium containing Ca2+, but not in medium containing K+. The results tend to reveal that the muscarinic receptor is involved in acetylcholine-induced stomatal movement. 展开更多
关键词 VICIAFABA L. STOMATA MOVEMENT ACETYLCHOLINE MUSCARINIC receptor.
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Over-expression of 72 ku protein of wheat yellow mosaic virus in E. coli and preparation of its antiserum 被引量:2
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作者 Yiming Xing Ning Su +2 位作者 Dawei Li Jialin Yu Yi Liu 《Chinese Science Bulletin》 SCIE EI CAS 2000年第6期525-528,共4页
By reverse transcription-polymerase chain reaction (RT-PCR), cDNA fragment of wheat yellow mosaic vir黶 (WYMV) RNA2 encoding 72 ku protein has been synthesized and cloned into plasmid pET30a(+) for overexpression in p... By reverse transcription-polymerase chain reaction (RT-PCR), cDNA fragment of wheat yellow mosaic vir黶 (WYMV) RNA2 encoding 72 ku protein has been synthesized and cloned into plasmid pET30a(+) for overexpression in prokaryotic celis. BL21(DE3) pLys S of E.coli transformed with the recombinant plasmid pETP72 containing the fragment has been induced to express the 72 ku protein on high level. The produced protein has been purified from sodium dodecyl sulfate-polyacrylamide gel (SDS-PAGE) for its antiserum preparation. in western-blotting analysis, the antibodies reacted with the 72 ku protein expressed in E.coli. 展开更多
关键词 wheat yellow MOSAIC virus 72 KU protein PROKARYOTIC cell expression ANTISERUM .
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Localization of muscarinic acetylcholine receptor in plant guard cells 被引量:2
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作者 Fanxia Meng Xin Liu +1 位作者 Shuqiu Zhang Chenghou Lou 《Chinese Science Bulletin》 SCIE EI CAS 2001年第7期586-588,618,共4页
Acetylcholine (ACh), as an important neuro-transmitter in animals, also plays a significant role in various kinds of physiological functions in plants. But relatively little is known about its receptors in plants. A g... Acetylcholine (ACh), as an important neuro-transmitter in animals, also plays a significant role in various kinds of physiological functions in plants. But relatively little is known about its receptors in plants. A green fluorescence BODIPY FL-labeled ABT, which is a high affinity ligand of muscarinic acetylcholine receptor (mAChR), was used to localize mAChR in plant guard cells. In Vicia faba L. and Pisum sativum L., mAChR was found both on the plasma membrane of guard cells. mAChR may also be distributed on guard cell chloroplast membrane of Vicia faba L. The evidence that mAChR localizes in the guard cells provides a new possible signal transduction pathway in ACh mediated stomata movement. 展开更多
关键词 GUARD cell MACHR FLUORESCENT LOCALIZATION VICIA faba L. PISUM sativum L.
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Identification and role of plasma membrane aquaporin in maize root 被引量:2
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作者 Meijun Zhu Xuechen Wang Jia Chen 《Chinese Science Bulletin》 SCIE EI CAS 2000年第16期1493-1496,共4页
Using antiserum against expressed aquaporin fusion protein, GST-RD28, the distribution of aquaporin in the plasma membrane of maize root protoplasts has been examined under confocal laser scanning microscopy by indire... Using antiserum against expressed aquaporin fusion protein, GST-RD28, the distribution of aquaporin in the plasma membrane of maize root protoplasts has been examined under confocal laser scanning microscopy by indirect fluorescence staining. Results indicate that there are abundant aquaporins in maize roots, which are distributed in plasma membrane unevenly. Western blotting analysis of total protein solubilized from maize root plasma membrane shows that antiserum against GST-RD28 can cross-react with one protein around 55 ku. Another 28 ku protein can also be detected when the concentration of SDS and DTT in SDS-PAGE sample buffer is increased. The 55 and 28 ku proteins may be dimeric and monomeric of aquaporin respectively. Functional experiments show that aquaporin blocker HgCI2 and aquaporin antiserum can suppress the swelling of maize root protoplasts in hypotonic solution, indicating that aquaporin in plasma membrane of protoplast facilitates rapid transmembrane water flow. 展开更多
关键词 AQUAPORIN plasma MEMBRANE TRANSMEMBRANE water flow MAIZE roots.
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Membrane skeleton spectrin in pollen and pollen tube 被引量:2
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作者 Yan Li Longfei Yan +1 位作者 S. Y. Zee B. Q. Huang 《Chinese Science Bulletin》 SCIE EI CAS 1999年第10期930-933,961,共5页
Immuno-western blots, immunofluorescence and immuno-gold labeling methods were used to study the existence and distribution of a homologue of the membrane skeleton spectrin in the pollen and pollen tube of Lilium davi... Immuno-western blots, immunofluorescence and immuno-gold labeling methods were used to study the existence and distribution of a homologue of the membrane skeleton spectrin in the pollen and pollen tube of Lilium davidii Duch. A spectrin homologue was found to exist in the pollen and pollen tube, distributed on membranes of secretory vesicles near Golgi apparatus. 展开更多
关键词 MEMBRANE SKELETON SPECTRIN immuno-blots and LABEL POLLEN plant cell.
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The Tartary Buckwheat Genome Provides Insights into Rutin Biosynthesis and Abiotic Stress Tolerance 被引量:54
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作者 Zhang, Lijun Li, Xiuxiu +18 位作者 Ma, Bin Gao, Qiang Du, Huilong Han, Yuanhuai Li, Yan Cao, Yinghao Qi, Ming Zhu, Yaxin Lu, Hongwei Ma, Mingchuan Liu, Longlong Zhou, Jianping Nan, Chenghu Qin, Yongjun Wang, Jun Cui, Lin Liu, Huimin Liang, Chengzhi Qiao, Zhijun 《Molecular Plant》 SCIE CAS CSCD 2017年第9期1224-1237,共14页
Tartary buckwheat (Fagopyrum tataricum) is an important pseudocereal crop that is strongly adapted to growth in adverse environments. Its gluten-free grain contains complete proteins with a well-balanced composition... Tartary buckwheat (Fagopyrum tataricum) is an important pseudocereal crop that is strongly adapted to growth in adverse environments. Its gluten-free grain contains complete proteins with a well-balanced composition of essential amino acids and is a rich source of beneficial phytochemicals that provide significant health benefits. Here, we report a high-quality, chromosome-scale Tartary buckwheat genome sequence of- 489.3 Mb that is assembled by combining whole-genome shotgun sequencing of both Illumina short reads and single-molecule real-time long reads, sequence tags of a large DNA insert fosmid library, Hi-C sequencing data, and BioNano genome maps. We annotated 33 366 high-confidence protein-coding genes based on expression evidence. Comparisons of the intra-genome with the sugar beet genome revealed an independent whole-genome duplication that occurred in the buckwheat lineage after they diverged from the common ancestor, which was not shared with rosids or asterids. The reference genome facilitated the identification of many new genes predicted to be involved in rutin biosynthesis and regulation, aluminum stress resistance, and in drought and cold stress responses. Our data suggest that Tartary buckwheat's ability to tolerate high levels of abiotic stress is attributed to the expansion of several gene families involved in signal transduction, gene regulation, and membrane transport. The availability of these genomic resources will facilitate the discovery of agronomically and nutritionally important genes and genetic improvement of Tartary buckwheat. 展开更多
关键词 tartary buckwheat de novo genome assembly rutin biosynthesis aluminum resistance abiotic stress whole genome duplication
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Follicles were reconstituted from dissociated mouse fetal ovarian cells in vitro 被引量:1
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作者 Haibin Wang Guoliang Xia +2 位作者 Qun Wang Meiling Li Zhongxian Lu 《Chinese Science Bulletin》 SCIE EI CAS 2001年第8期672-674,共3页
Early folliculogenesis involved in the interaction of germ cells and somatic cells is a complicated physiological event. Female germ cells are committed to differentiate into oocytes and finish complete development in... Early folliculogenesis involved in the interaction of germ cells and somatic cells is a complicated physiological event. Female germ cells are committed to differentiate into oocytes and finish complete development in the functional units of follicles. Thus there will be great significance in basal research and practices to evaluate the possibility of ovarian cells to reconstitute into follicles in vitro. In the present research, 12-16 dpc (days post coitum) mouse fetal ovarian cells were respectively isolated using collagenase digestion and cultured in droplets in vitro. The results revealed that the fetal ovarian cells of 12-16 dpc appeared to form multiple cell aggregates and tissue-like pieces in vitro. However, 12-13 dpc ovarian cells failed to form the follicles. 14-15 dpc ovarian cells were competent to form a few follicle-like complexes. Furthermore many small typical follicles were reconstituted from 16 dpc ovarian cells in vitro. The results showed for the first time that mouse embryonic 展开更多
关键词 MOUSE fetal OVARY RECONSTITUTION in VITRO follicle.
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