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Dwarf尺寸的进一步缩减 被引量:1
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作者 向隆刚 龚健雅 《计算机科学》 CSCD 北大核心 2007年第7期103-105,170,共4页
Dwarf不仅降低了数据立方的存储开销,而且具有结构简单、易于实现、查询和维护等优点,是一种比较理想的数据立方组织方法。为了进一步缩减Dwarf的存储尺寸,本文通过研究Dwarf结构,分别提出了浓缩Dwarf和冰山Dwarf:前者从Dwarf结构中删... Dwarf不仅降低了数据立方的存储开销,而且具有结构简单、易于实现、查询和维护等优点,是一种比较理想的数据立方组织方法。为了进一步缩减Dwarf的存储尺寸,本文通过研究Dwarf结构,分别提出了浓缩Dwarf和冰山Dwarf:前者从Dwarf结构中删除了对于查询来说冗余的内容,而后者从Dwarf结构中去掉了对于用户来说琐碎的内容。实验和分析表明,浓缩Dwarf有效地减小了Dwarf的存储尺寸,而冰山Dwarf适合于忽略细节的应用场合,极大地降低了Dwarf的存储开销。 展开更多
关键词 数据立方 dwarf 浓缩dwarf 冰山dwarf
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The phytohormone jasmonic acid is involved in rice resistance to Southern rice black-streaked dwarf virus 被引量:1
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作者 Chaorui Huang Qing Liu +7 位作者 Qingling Qi Chenfei Gao Lulu Li Yanjun Li Jianping Chen Zongtao Sun Jianlong Xu Hehong Zhang 《The Crop Journal》 2025年第1期23-30,共8页
Viruses are significant pathogens causing severe plant infections and crop losses globally.The resistance mechanisms of rice to viral diseases,particularly Southern rice black-streaked dwarf virus(SRBSDV),remain poorl... Viruses are significant pathogens causing severe plant infections and crop losses globally.The resistance mechanisms of rice to viral diseases,particularly Southern rice black-streaked dwarf virus(SRBSDV),remain poorly understood.In this study,we assessed SRBSDV susceptibility in 20 Xian/indica(XI)and 20 Geng/japonica(GJ)rice varieties.XI-1B accessions in the Xian subgroup displayed higher resistance than GJ accessions.Comparative transcriptome analysis revealed changes in processes like oxidoreductase activity,jasmonic acid(JA)metabolism,and stress response.JA sensitivity assays further linked antiviral defense to the JA pathway.These findings highlight a JA-mediated resistance mechanism in rice and offer insights for breeding SRBSDV-resistant varieties. 展开更多
关键词 Oryza sativa(rice) Jasmonic acid Southern rice black-streaked dwarf virus(SRBSDV) Variety resistance Defense response
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Natural variation of ClCCT promoter promotes flowering and dwarfing in adlay(Coix lacryma-jobi L.)
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作者 Jieliang Bao Yanan Wang +11 位作者 Kuoshu Cui Xiangdong Li Hong Pan Chaoyuan Shi Xiang Yan Jinglin Wang Xiaotong Wang Qing Dou Xiaolong Dong Yibing Yuan Shufeng Zhou Chao Guo 《The Crop Journal》 2025年第3期942-951,共10页
The flowering time is a key trait that determines adaptation,yield and quality of crops.Adlay,a traditional cereal crop,has developed a distinctive agricultural industry in Southwest China and Southeast Asian countrie... The flowering time is a key trait that determines adaptation,yield and quality of crops.Adlay,a traditional cereal crop,has developed a distinctive agricultural industry in Southwest China and Southeast Asian countries.However,the currently planted varieties are all semi-domesticated landraces with delayed flowering and excessive height.These defects limit yield improvement per unit area and mechanized harvesting.In this study,a major QTL associated with flowering time and plant height in adlay has been mapped and identified as Cl CCT,a gene having a conserved function and regulatory pathway for inhibiting flowering time and increasing plant height in gramineous crops.Among the six identified haplotypes of Cl CCT,the haplotype with 38-bp insertion in promoter region of Cl CCT has earlier flowering time and wider geographical distribution than other haplotypes.The insertion variation,which arises from the segmental duplication of Cl CCT,can inhibit the expression level of reporter gene and has been used in breeding for early maturity and dwarfing.These research results not only reinforce our understanding of the importance of CCT domain protein in the tropical crops adapting to high-latitude environment,but also provide a validated breeding target for the early maturity and dwarfing of adlay. 展开更多
关键词 Early maturity dwarfING CCT domain Convergent selection Genome duplication event
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Enhanced Multi-Object Dwarf Mongoose Algorithm for Optimization Stochastic Data Fusion Wireless Sensor Network Deployment
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作者 Shumin Li Qifang Luo Yongquan Zhou 《Computer Modeling in Engineering & Sciences》 2025年第2期1955-1994,共40页
Wireless sensor network deployment optimization is a classic NP-hard problem and a popular topic in academic research.However,the current research on wireless sensor network deployment problems uses overly simplistic ... Wireless sensor network deployment optimization is a classic NP-hard problem and a popular topic in academic research.However,the current research on wireless sensor network deployment problems uses overly simplistic models,and there is a significant gap between the research results and actual wireless sensor networks.Some scholars have now modeled data fusion networks to make them more suitable for practical applications.This paper will explore the deployment problem of a stochastic data fusion wireless sensor network(SDFWSN),a model that reflects the randomness of environmental monitoring and uses data fusion techniques widely used in actual sensor networks for information collection.The deployment problem of SDFWSN is modeled as a multi-objective optimization problem.The network life cycle,spatiotemporal coverage,detection rate,and false alarm rate of SDFWSN are used as optimization objectives to optimize the deployment of network nodes.This paper proposes an enhanced multi-objective mongoose optimization algorithm(EMODMOA)to solve the deployment problem of SDFWSN.First,to overcome the shortcomings of the DMOA algorithm,such as its low convergence and tendency to get stuck in a local optimum,an encircling and hunting strategy is introduced into the original algorithm to propose the EDMOA algorithm.The EDMOA algorithm is designed as the EMODMOA algorithm by selecting reference points using the K-Nearest Neighbor(KNN)algorithm.To verify the effectiveness of the proposed algorithm,the EMODMOA algorithm was tested at CEC 2020 and achieved good results.In the SDFWSN deployment problem,the algorithm was compared with the Non-dominated Sorting Genetic Algorithm II(NSGAII),Multiple Objective Particle Swarm Optimization(MOPSO),Multi-Objective Evolutionary Algorithm based on Decomposition(MOEA/D),and Multi-Objective Grey Wolf Optimizer(MOGWO).By comparing and analyzing the performance evaluation metrics and optimization results of the objective functions of the multi-objective algorithms,the algorithm outperforms the other algorithms in the SDFWSN deployment results.To better demonstrate the superiority of the algorithm,simulations of diverse test cases were also performed,and good results were obtained. 展开更多
关键词 Stochastic data fusion wireless sensor networks network deployment spatiotemporal coverage dwarf mongoose optimization algorithm multi-objective optimization
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Eleven Local Volume Dwarf Galaxies in the FASHI Survey
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作者 Aleksandra Nazarova Dmitry Makarov +2 位作者 Igor Karachentsev Chuan-Peng Zhang Ming Zhu 《Research in Astronomy and Astrophysics》 2025年第12期157-166,共10页
We determined HI parameters for eleven nearby late-type dwarf galaxies using FASHI data cubes,despite the fact that the first version of the FAS HI catalog does not list any radio sources that could correspond to thes... We determined HI parameters for eleven nearby late-type dwarf galaxies using FASHI data cubes,despite the fact that the first version of the FAS HI catalog does not list any radio sources that could correspond to these galaxies.Four of them are probable peripheral satellites of the bright spiral galaxies:NGC 3556,NGC 4258,NGC 4274 and NGC 4490,while others are isolated objects.The considered sample has the following median parameters:a heliocentric velocity of V_(h)=542 km s^(-1),an HI-line width of W_(50)=28 km s^(-1),a hydrogen mass of log(M_(HI)/M_(⊙))=6.83,a stellar mass of log(M_(*)/M_(⊙))=7.19,and a specific star formation rate of sSFR=-10.17 yr^(-1). 展开更多
关键词 galaxies:dwarf surveys galaxies:distances and redshifts
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Properties of Standard,Fuzzy,and Self-interacting Dark Matter Haloes in Dwarf Galaxies
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作者 Fahmi M.Al Farisy Hesti R.T.Wulandari Azriel J.Dante 《Research in Astronomy and Astrophysics》 2025年第4期194-208,共15页
This study examines the properties of standard cold dark matter(CDM),fuzzy dark matter(FDM),and selfinteracting dark matter(SIDM)haloes by analyzing the rotation curves of selected dwarf galaxies from SPARC and LITTLE... This study examines the properties of standard cold dark matter(CDM),fuzzy dark matter(FDM),and selfinteracting dark matter(SIDM)haloes by analyzing the rotation curves of selected dwarf galaxies from SPARC and LITTLE THINGS in 3D catalogs.Utilizing the Markov Chain Monte Carlo(MCMC)method for model fitting and Bayesian Information Criterion for model comparison,we find that compared to CDM,both FDM and SIDM haloes generally provide better fits to the observed rotation curves.Our findings reveal that the concentration–mass relation derived from the dark matter-only simulations is not followed by concentrations or masses obtained from the rotation curve data.Our analysis highlights a positive correlation between the core sizes of FDM and SIDM haloes and the effective radius of the galaxy,attributable to gravitational couplings between baryonic and dark matter components.Moreover,our exploration of dark matter fractions at characteristic radii indicates considerable diversity in dark matter distributions across dwarf galaxies.Notably,FDM and SIDM exhibit greater diversity than CDM in this respect. 展开更多
关键词 galaxies:dwarf galaxies:kinematics and dynamics galaxies:haloes (cosmology:)dark matter
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Producing Type Ia Supernovae from Hybrid CONe White Dwarfs with Mainsequence Binary Companions at Low Metallicity of Z=0.0001
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作者 Boyang Guo Xiangcun Meng +2 位作者 Zhijia Tian Jingxiao Luo Zhengwei Liu 《Research in Astronomy and Astrophysics》 2025年第1期344-356,共13页
The nature of progenitors of Type Ia supernovae(SNe Ia)and their explosion mechanism remains unclear.It has been suggested that SNe Ia may have resulted from thermonuclear explosions of hybrid carbon-oxygen-neon white... The nature of progenitors of Type Ia supernovae(SNe Ia)and their explosion mechanism remains unclear.It has been suggested that SNe Ia may have resulted from thermonuclear explosions of hybrid carbon-oxygen-neon white dwarfs(CONe WDs)when they grow in mass to approach the Chandrasekhar mass limit by accreting matter from a binary main-sequence(MS)companion.In this work,we combine the results of detailed binary evolution calculations with population synthesis models to investigate the rates and delay times of SNe Ia in the CONe WD+MS channel at a low metallicity environment of Z=0.0001.For a constant star formation rate of 5M_(⊙)yr^(−1),our calculations predict that the SN Ia rates in the CONe WD+MS channel at low metallicity of Z=0.0001 is about 0.11−3.89×10^(−4) yr^(−1).In addition,delay times in this channel cover a wide range of 0.05−2.5 Gyr.We further compare our results to those given by a previous study for the CONe WD+MS channel with a higher metallicity of Z=0.02 to explore the influence of metallicity on the results.We find that these two metallicity environments give a slight difference in rates and delay times of SNe Ia from the CONe WD+MS channel,although SNe Ia produced at a low metallicity environment of Z=0.0001 have relatively longer delay times. 展开更多
关键词 methods numerical-(stars:)binaries(including multiple) close-stars evolution-(stars:)supernovae general-(stars:)white dwarfs
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水稻矮化并花发育异常突变体dwarf and deformed flower 2(ddf2)的基因定位与候选基因分析 被引量:8
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作者 张玲 郭爽 +5 位作者 汪玲 张天泉 庄慧 龙珏臣 何光华 李云峰 《中国农业科学》 CAS CSCD 北大核心 2015年第10期1873-1881,共9页
【目的】对一个同时导致营养和生殖器官发育异常的水稻突变体进行表型鉴定、基因定位和候选基因分析,为下一步的基因克隆与功能分析奠定基础。【方法】在水稻籼型恢复系602组织培养后代中,发现一个矮化并花发育异常突变体dwarf and defo... 【目的】对一个同时导致营养和生殖器官发育异常的水稻突变体进行表型鉴定、基因定位和候选基因分析,为下一步的基因克隆与功能分析奠定基础。【方法】在水稻籼型恢复系602组织培养后代中,发现一个矮化并花发育异常突变体dwarf and deformed flower 2(ddf2)。抽穗期,以野生型为对照,对ddf2株高、主穗长、节间和功能叶的长宽等性状进行统计分析;同时利用冷冻切片等技术对茎、叶和花器官进行详细的形态和组织学分析。分别以西农1A和中花11为母本,以DDF2/ddf2杂合株系为父本构建2个F2群体进行遗传分析和基因定位,并对候选基因进行实时荧光定量PCR(real-time PCR)分析。【结果】相较于野生型,突变体各节间的长和茎粗均极显著降低,叶片极显著变短、变窄,同时花序也极显著变短。组织细胞学分析发现,突变体大叶脉数目和相邻2个大叶脉之间的小叶脉数都没有明显的变化,但相邻2个大叶脉之间的宽度明显减小,进一步比较2个小叶脉之间的叶肉细胞,发现在突变体中细胞数目和尺寸均显著降低;突变体茎秆维管束的数目与野生型相比没有明显的变化,但统计发现2个大维管束之间基本组织细胞的数量和细胞的大小都显著小于野生型,表明ddf2突变体茎、叶细胞分裂和膨胀都受到了抑制;此外,ddf2突变体的花器官特征发育受到了严重干扰:第一轮外稃顶部弯曲、内稃不同程度退化,第三轮雄蕊器官严重退化,部分甚至转化为雌蕊状器官,另外部分ddf2小穗的护颖过度发育,转变成稃片状,一些小穗还表现分生组织确定性的丢失,发育出2个以上的小花。遗传分析表明该突变性状受1对隐性基因控制。利用中花11/ddf2的1 024株F2分离群体,最终将DDF2精细定位在第11染色体短臂近着丝粒位置处,位于insertion/deletion(in/del)标记S-11和S-14之间,遗传距离分别为0.049和0.098c M,物理距离为90.295 kb,并与标记S-24共分离。分析定位区间的基因,发现共有MSU注释基因12个,其中一个编码Sec3_C蛋白的LOC_Os11g17600内部包含共分离标记S-24,进一步对该基因进行表达分析,发现该基因在突变体的叶、茎和穗中都表现出明显的下调,初步将LOC_Os11g17600作为DDF2候选基因。【结论】DDF2是一个同时控制水稻茎/叶和花器官发育的新基因。 展开更多
关键词 水稻 矮化 花器官 dwarf and DEFORMED FLOWER 2(ddf2) 基因定位
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两个新水稻 Dwarf18 基因强等位突变体的表型分析及分子鉴定 被引量:3
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作者 侯雷 袁守江 +4 位作者 尹亮 赵金凤 万国峰 张文会 李学勇 《作物学报》 CAS CSCD 北大核心 2012年第8期1416-1424,共9页
通过EMS诱变日本晴获得了s2-9和s1-146a两个矮秆突变体,其植株矮小,成熟期株高分别为日本晴的26.3%和19.2%;苗期叶片较宽,叶色深绿;穗型仍为散穗但穗长变短,粒型未发生改变。对水稻胚乳的α-淀粉酶诱导实验表明,这2个矮秆突变体与GA的... 通过EMS诱变日本晴获得了s2-9和s1-146a两个矮秆突变体,其植株矮小,成熟期株高分别为日本晴的26.3%和19.2%;苗期叶片较宽,叶色深绿;穗型仍为散穗但穗长变短,粒型未发生改变。对水稻胚乳的α-淀粉酶诱导实验表明,这2个矮秆突变体与GA的信号传导途径无关,外源活性GA3对水稻幼苗株高的促进实验显示它们应与赤霉素的生物合成有关。利用突变体与籼稻品种Dular分别杂交构建了F2群体,精细定位表明这2个突变体的表型与水稻Dwarf18(D18)基因紧密连锁。序列分析发现这2个矮秆突变体的D18基因均发生了突变,在s2-9突变体中D18基因的内含子3'拼接点发生单碱基突变,s1-146a中D18基因编码区的单碱基突变导致提前终止密码子的出现。RT-PCR结果显示,在s1-146a中D18基因表达明显增强,但在s2-9中未检测到D18基因的表达。 展开更多
关键词 水稻 矮秆突变体 dwarf18 赤霉素 精细定位
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Molecular Tagging of a New Resistance Gene to Maize Dwarf Mosaic Virus Using Microsatellite Markers 被引量:6
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作者 吴建宇 汤继华 +1 位作者 夏宗良 陈伟程 《Acta Botanica Sinica》 CSCD 2002年第2期177-180,共4页
With joint analysis based on the parents, F 1, F 2 and backcrosses, the authors found that the resistance of the maize inbred line Huangzaosi to the maize dwarf mosaic virus strain B was conditioned by a major gene ... With joint analysis based on the parents, F 1, F 2 and backcrosses, the authors found that the resistance of the maize inbred line Huangzaosi to the maize dwarf mosaic virus strain B was conditioned by a major gene and polygene, and identified a new major gene. Bulked segregate and microsatellite analysis of a F 2 progeny from the combination of Huangzaosi×Mo17 were used to identify the resistance gene, mdm1(t), on the long arm of chromosome 6. This new resistance gene is tightly linked to and located between the microsatellite markers loci, phi077 and bnlg391. The linkage distances between phi077-mdm1(t) and mdm1(t)-bnlg391 are 4.74 centiMorgan (cM) and 6.72 cM respectively. 展开更多
关键词 MAIZE maize dwarf mosaic virus resistance gene MICROSATELLITE molecular tagging
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MapReduce环境下的并行Dwarf立方构建 被引量:3
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作者 师金钢 鲍玉斌 +1 位作者 冷芳玲 于戈 《计算机科学与探索》 CSCD 2011年第5期398-409,共12页
针对数据密集型应用,提出了一种基于MapReduce框架的并行Dwarf数据立方构建算法。算法将传统Dwarf立方等价分割为多个独立的子Dwarf立方,采用MapReduce架构,实现了Dwarf立方的并行构建、查询和更新。实验证明,并行Dwarf算法一方面结合了... 针对数据密集型应用,提出了一种基于MapReduce框架的并行Dwarf数据立方构建算法。算法将传统Dwarf立方等价分割为多个独立的子Dwarf立方,采用MapReduce架构,实现了Dwarf立方的并行构建、查询和更新。实验证明,并行Dwarf算法一方面结合了MapReduce框架的并行性和高可扩展性,另一方面结合了Dwarf立方结构的数据高压缩性及数据自索引性。并行Dwarf立方既实现了数据立方的高压缩存储,提供了快速的构造和增量更新操作,又克服了MapReduce机制没有索引的劣势,实现了数据立方上的快速查询操作。 展开更多
关键词 数据密集计算 MAPREDUCE dwarf 数据立方
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Molecular Tagging and Effect Analysis of a New Small Grain Dwarf Gene in Rice 被引量:4
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作者 李秀兰 吴成 +3 位作者 邓晓建 王平荣 李仁端 杨志荣 《Acta Botanica Sinica》 CSCD 2003年第7期757-761,共5页
Plant height is one of the important agronomic traits of rice. Over higher plant would easily result in plant lodging and output reducing. On the other hand, the dwarf varieties with proper plant height had higher lod... Plant height is one of the important agronomic traits of rice. Over higher plant would easily result in plant lodging and output reducing. On the other hand, the dwarf varieties with proper plant height had higher lodging resistance and a greater harvest index, allowing for the increased use of nitrogen fertilizer. Dwarf breeding had made a great breakthrough in the rice breeding. The breeding and extension of excellent dwarf varieties remarkably improved the yield potential of rice. Therefore, the plant height is still one of the focuses in rice genetic research. 展开更多
关键词 Oryza sativa dwarf gene gene mapping microsatellite marker gene effect analysis
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基于DWARF的Bootloader远程交叉调试模型 被引量:5
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作者 张和君 张跃 《计算机工程》 EI CAS CSCD 北大核心 2006年第24期60-62,共3页
研究了嵌入式系统在Bootloader单支撑环境下的远程交叉调试问题,设计并实现了Bootloader远程交叉调试模型,并达到源码级别的调试。主机端采用DWARF调试规范,负责分析目标文件的调试信息,向目标机上的Bootloader发送机器级的调试命令;Boo... 研究了嵌入式系统在Bootloader单支撑环境下的远程交叉调试问题,设计并实现了Bootloader远程交叉调试模型,并达到源码级别的调试。主机端采用DWARF调试规范,负责分析目标文件的调试信息,向目标机上的Bootloader发送机器级的调试命令;Booloader接收并处理调试命令。该模型为嵌入式系统的应用程序开发提供了良好的调试手段。 展开更多
关键词 引导装载程序 远程交叉调试 dwarf调试规范 嵌入式系统
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Construction of Mutant Population and Analysis of Dwarf Mutants in "6421"(Capsicum annuum L.)through EMS Mutagenesis 被引量:3
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作者 杨博智 周书栋 +6 位作者 欧立军 刘周斌 马艳青 陈文超 张竹青 戴雄泽 邹学校 《Agricultural Science & Technology》 CAS 2016年第6期1322-1325,1408,共5页
[Objective] The aim was to improve the genetic property of peppers, the mutant population of Capsicum annuum L cultivar "6421" was constructed. [Method] The seeds of "6421" were treated with 0.2% to 1.2% ethyl met... [Objective] The aim was to improve the genetic property of peppers, the mutant population of Capsicum annuum L cultivar "6421" was constructed. [Method] The seeds of "6421" were treated with 0.2% to 1.2% ethyl methane sulfonate to identified LD50, and then 10 000 LD^o of treated seeds were sowed to construct mutant population. The agronomic characters and genetic regularity of dwarf mutants in M4 generation were analyzed. [Result] Our results showed that GR and SSR were 45.2% and 40.2% respectively at 1.0% EMS, close to LD50, with GI (17.6) and seed Ⅵ (19.7) being half of that of control; 562 M4 mutants were identified in 2015, and the mutation could be characterized according 11 major categories and 32 subcategories; Simultaneously, we found that plant height, plant width, diameter of mainstem, length of main-stem, the number of main-stem nodes and branch of lines E29, E58, E142 and E312 were all significantly different from that of the control. The mutation of lines E29, E58 and E312 was all controlled by a single recessive gene. [Conclusionl The study first created a pepper mutant population, which provides not only the germplasm resources for further breeding but also direct and effective materials for genomic study of the pepper. 展开更多
关键词 Capsicum annuum L-. EMS MUTAGENESIS Mutant population construc-tion dwarf mutants
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Evaluation of Productivity and Light Quality in Two High Density Dwarf Rootstock Apple Orchards in Central China 被引量:3
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作者 高登涛 郭景南 +2 位作者 魏志峰 范庆锦 杨朝选 《Agricultural Science & Technology》 CAS 2012年第9期1848-1853,2011,共7页
[Ohjective] The aim of the study is to investigate the productivity and light quality in two high density M26 dwarf rootstock apple orchards in central China so as to provide some management guidance for close plantin... [Ohjective] The aim of the study is to investigate the productivity and light quality in two high density M26 dwarf rootstock apple orchards in central China so as to provide some management guidance for close planting of dwarf rootstock apples.[Method] The technical parameters of individual trees and group parameters as shoot number and composition and canopy coverage were determined, and the light quality in the canopy, fruit production and quality were investigated. [Result] Slender spindle (SS) orchard has 54 thousands shoots per 667 m^2. Coverage rate is 76%. Leaf area index is 1.9. The ratio of long, medium and spur shoots is 1:1:8. Fruit yield is 3 263 kg/667 m^2 with 85% first grade fruit. Light interception in the canopy is 58% while the ratio of canopy with good light is 65%. Modified slender spindle (MSS) orchard has 93 thousands shoots per 667 m^2 and the coverage is 77%. Leaf area index is 3.3. The ratio cf long, medium and spur shoots is 1:2:7. Fruit yield is 3 931 kg/667 m^2 with 85% first grade fruit. The light interception in the canopy is 73% while the ratio of canopy with good light is 35%. [Conclusion] Apple orchard with M26 dwarf rootstock trained as SS and MSS tree form in medium planting density may be useful to the management of the similar orchards in Central China. 展开更多
关键词 Apple trees on dwarf rootstocks High density planting Tree form Pro-ductivity Light quality
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Identification of Molecular Markers for the Thinopyrum intermedium Chromosome 2Ai-2 with Resistance to Barley Yellow Dwarf Virus 被引量:4
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作者 张增艳 辛志勇 +2 位作者 林志珊 陈孝 王晓萍 《Acta Botanica Sinica》 CSCD 2000年第10期1051-1056,共6页
The wheat_ Thinopyrum intermedium addition lines Z1,Z2 contain a pair of Th. intermedium chromosomes 2Ai_2 carrying the gene with resistance to barley yellow dwarf virus (BYDV). Genomic in situ hybridizat... The wheat_ Thinopyrum intermedium addition lines Z1,Z2 contain a pair of Th. intermedium chromosomes 2Ai_2 carrying the gene with resistance to barley yellow dwarf virus (BYDV). Genomic in situ hybridization (GISH) was used to analyze the chromosome constitution of Z1,Z2 by using genomic DNA probes from Th. intermedium and Pseudoroegneria strigosa . The results showed that the chromosome constitution of either Z1 or Z2 composes of 42 wheat chromosomes and two Th. intermedium chromosomes (2Ai_2). The 2Ai_2 chromosome is St_E intercalary translocation, in which the E genomic chromosome segment translocated into the middle region of the long arm of chromosome belonging to St genome. With the genomic DNA probe of Ps. strigosa , the GISH pattern specific to the 2Ai_2 chromosome may be used as a molecular cytogenetic marker. A detailed RFLP analysis on Z1, Z2 and their parents was carried out by using 12 probes on the wheat group 2 chromosomes. Twenty RFLP markers specific to the 2Ai_2 chromosome were identified. Two RAPD markers of OPR16 -350 and OPH09 -1580 , specific to the 2Ai_2 chromosome, were identified from 280 RAPD primers. These molecular markers could be used to assisted_select translocation lines with small segment of the 2Ai_2 chromosome and provide tools to localize the BYDV resistance. 展开更多
关键词 barley yellow dwarf virus (BYDV) Thinopyrum intermedium addition lines genomic in situ hybridization (GISH) RFLP RAPD
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一种基于Dwarf的快速有效增量更新算法 被引量:1
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作者 印莹 赵宇海 张斌 《计算机科学》 CSCD 北大核心 2005年第11期88-90,129,共4页
数据立方计算是代价非常大的操作,并且被广泛研究。受空间的限制,存储一个完全实例化的数据立方是不可行的。最近提出的一种语义压缩数据立方—Dwarf,通过消除前缀冗余和后缀冗余把一个完全实例化的数据立方压缩存储到一个很小的空间。... 数据立方计算是代价非常大的操作,并且被广泛研究。受空间的限制,存储一个完全实例化的数据立方是不可行的。最近提出的一种语义压缩数据立方—Dwarf,通过消除前缀冗余和后缀冗余把一个完全实例化的数据立方压缩存储到一个很小的空间。然而,当数据源发生变化时,它的更新过程是很复杂的。本文通过研究Dwarf在更新过程中汇总结点的变化特性,提出了一种基于Dwarf的新的增量更新算法,既能完全实例化数据立方又不需要重新计算,大大提高了数据立方的更新效率。实验进一步证明了该算法的效率和有效性,尤其适合数据仓库中的高维数据集。 展开更多
关键词 数据仓库 前缀冗余 dwarf 增量更新 增量更新算法 数据立方 压缩存储 更新过程 实例化 发生变化
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Study on High-Eefficient Breeding Technology Platform of Dwarf Male-Sterile Wheat 被引量:2
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作者 刘莹 赵翠荣 +1 位作者 王立峰 陈科海 《Agricultural Science & Technology》 CAS 2011年第4期524-526,共3页
[Purpose] The paper is to discuss the high-efficient breeding technology platform of dwarf male-sterile wheat.[Method] Conclusion was made upon the development of the creation and application of dwarf male-sterile whe... [Purpose] The paper is to discuss the high-efficient breeding technology platform of dwarf male-sterile wheat.[Method] Conclusion was made upon the development of the creation and application of dwarf male-sterile wheat,and the conception of introducing haploid breeding technology into the technological system of high-efficient breeding of dwarf male-sterile wheat was proposed.[Result] Dwarf male-sterile wheat not only retains the properties of total male abortion of Taigu Genetic Sterile Wheat,steady sterility,and high hybrid rate after open pollination,but also has the characteristic of high dwarfing ability of Aibian No.1,becoming a comparatively ideal population modification means.At present,the application of dwarf male-sterile wheat mainly includes germplasm resources platform of population modification by using dwarf male-sterile wheat,technology platform of constructing new high-efficient breeding system by using dwarf male-sterile wheat,and production platform of using dwarf male-sterile wheat to breed new varieties.Through the introduction of haploid breeding into the already established wheat high-efficient breeding system,a new system of high-efficient biological breeding technology of dwarf male-sterile wheat was constructed theoretically.[Conclusion] The study provides references to the further study and application of dwarf male-sterile wheat. 展开更多
关键词 dwarf male-sterile wheat Breeding platform Haploid breeding
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Study on the Effective Prevention and Control of Maize Rough Dwarf Disease in Different Areas with Varying Epidemic Intensity in Shandong Province 被引量:1
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作者 王升吉 赵玖华 +5 位作者 杨向黎 辛相启 吴斌 尚佑芬 张眉 袁圆圆 《Agricultural Science & Technology》 CAS 2014年第10期1703-1706,1709,共5页
[ Objective] This study aimed to investigate the effective prevention and control of maize rough dwarf disease in different areas with varying epidemic inten-sity in Shandong Province. [Method] Control effects of sing... [ Objective] This study aimed to investigate the effective prevention and control of maize rough dwarf disease in different areas with varying epidemic inten-sity in Shandong Province. [Method] Control effects of single application of virus in-hibitors and composite application of virus inhibitors with seed dressing agents and pesticides on maize rough dwarf disease in different areas with varying epidemic intensity were investigated. [Result] The same treatment possessed entirely different effects in severely affected areas and slightly affected areas. To be specific, single application of virus inhibitors in slightly affected areas exhibited good control effects, with a control efficiency of 76.59% and yield increment rate of 158.21%; in severely affected areas, single application of virus inhibitors led to low control efficiency and yield increment rate. The highest control efficiency of composite application of virus inhibitors with seed dressing agents and pesticides in severely affected areas was 71.38%, and experimental plots changed from total crop failure to have certain eco-nomic output. [Conclusion] ln different areas with varying epidemic intensity of maize rough dwarf disease, different application modes should be adopted according to lo-cal conditions, thereby saving cost and improving control efficiency. 展开更多
关键词 Maize rough dwarf disease Epidemic intensity Virus inhibitors Chemical control
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Molecular Characterization of Segments S7 to S10 of a Southern Rice Black-streaked Dwarf Virus Isolate from Maize in Northern China 被引量:28
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作者 Xiao Yin Fei-fei Xu +3 位作者 Fang-qiang Zheng Xiang-dong LI Bao-shen Liu Chun-qing Zhang 《Virologica Sinica》 SCIE CAS CSCD 2011年第1期47-53,共7页
Southern rice black-streaked dwarf virus (SRBSDV) is a novel Fijivirus prevalent in rice in southern and central China,and northern Vietnam. Its genome has 10 segments of double-stranded RNA named S1 to S10 according ... Southern rice black-streaked dwarf virus (SRBSDV) is a novel Fijivirus prevalent in rice in southern and central China,and northern Vietnam. Its genome has 10 segments of double-stranded RNA named S1 to S10 according to their size. An isolate of SRBSDV,JNi4,was obtained from naturally infected maize plants from Ji'ning,Shandong province,in the 2008 maize season. Segments S7 to S10 of JNi4 share nucleotide identities of 72.6%-73.1%,72.3%-73%,73.9%-74.5% and 77.3%-79%,respectively,with corresponding segments of Rice black-streaked dwarf virus isolates,and identities of 99.7%,99.1%-99.7%,98.9%-99.5%,and 98.6%-99.2% with those of SRBSDV isolates HN and GD. JNi4 forms a separate branch with GD and HN in the phylogenetic trees constructed with genomic sequences of S7 to S10. These results confirm the proposed taxonomic status of SRBSDV as a distinct species of the genus Fijivirus and indicate that JNi4 is an isolate of SRBSDV. Shandong is so far the northernmost region where SRBSDV is found in China. 展开更多
关键词 Southern rice black-streaked dwarf virus (SRBSDV) Maize rough dwarf disease (MRD) Identity Phylogenetic analysis
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