基于硬件加速的真三维显示体素化算法     

谭皓  杨忠  李玉峰  沈春林 《勤云标准版测试》2006,(1):59-64

提出了一种新的体素化算法，利用显示硬件支持二维光栅化算法和新的可编程控制功能，提高了体素化算法的效率。该算法通过逐层处理的方式将三维数据离散成为一系列的切片，利用硬件渲染完成切片的光栅化操作，将最终的光栅化结果组合成为体数据表达。算法利用可编程图形处理单元（GPU）的大规模纹理、动态顶点数据和灵活的纹理数据操作等特性，有效地降低了系统压力，提高了算法效能。实验证明，该算法满足真三维显示技术的要求。  相似文献   

sch蚕胚胎期温敏性的mRNA差异显示研究   总被引：1，自引：1，他引：0  

梁应霞  鲁成  李关荣  夏庆友  周泽扬  向仲怀 《蚕业科学》2001,27(4):267-271

采用mRNA差异显示技术对不同催青处理的伴性赤蚁sch系统进行研究 ,并以普通黑蚁系统夏芳作为对照。实验中分别抽提高温和常温催青处理 36h后的sch蚕卵和夏芳蚕卵的总RNA进行DDRT -PCR分析 ,其产物于变性聚丙烯酰胺凝胶上电泳展示 ,得到大量的差示片段。对高温催青处理后在夏sch蚕卵中特异表达的 2条能稳定重复的带进行了克隆 ,得到了长度分别为 2 73和 199bp的cDNA片段 ,并对其进行了序列分析。Northern杂交证实HAP82 80仅在高温催青处理的夏sch蚕卵中有转录 ,表明其为sch蚕卵经高温催青处理后特异表达的产物  相似文献   

东北亚四国（地区）SMV株系毒力比较   总被引：1，自引：0，他引：1  

张明厚  魏培文 《大豆科学》1998,17(2):101-107

将我国，韩国，日本及俄罗斯远东地区的ＳＭＶ株系与鉴别寄主交互接种测定其毒力。结果指出采用外国的株系鉴别寄坟难以区分我国株系毒力。同样，用我国鉴别寄坟也难以区分外国毒株的毒力，所测定的我国９个株系的１３个代表毒株全部能侵染最抗病的鉴别寄主韩国的Ｂｕｆｆａｌｏ和日本的Ｈａｒｏｊｏｙ。  相似文献   

大豆孢囊线虫4号生理小种侵染大豆根系诱导表达的cDNA分析   总被引：1，自引：0，他引：1  

吕蓓  方宣钧 《分子植物育种》2003,1(2):193-200

大豆孢囊线虫(Heterodera glycines Ichinohe；Soybean Cyst Nematode，SCN)是一种土传的专性内寄生线虫。SCN的二龄幼虫侵入到大豆幼嫩的根组织中，导致大豆根内的细胞变形并与之形成“合胞体”。合胞体在形态上和生理上的变化是SCN直接诱导大豆基因表达的结果。本研究以高抗SCN的灰布支黑豆为材料，用大豆孢囊线虫二龄幼虫直接接种大豆的根系，应用DDRT—PCR技术及RDB(Reversedot—blotting)杂交鉴定，获得6个阳性cDNA克隆，分别是SCN侵染后5天的A32克隆(GenBank登录号为B1173978)；侵染后10天的B12克隆(GenBank登录号为B1173979)、B71克隆(GenBank登录号为B1173980)；侵染后15天的Cll克隆(GenBank登录号为B1173981)、CPl2(GenBank登录号为B1173982)克隆和CP32克隆(GenBank登录号为B1173983)。序列的同源比较表明，6个cDNA均与Shoemaker构建的大豆基因表达库中的cDNA序列有非常高的同源性，证明这些cDNA是大豆基因表达的产物。其中A32克隆的序列与控制拟南芥下胚轴生长的MYB转录因子、营养元素缺失诱导的番茄根的表达文库中的一个cDNA及番茄抗假单胞杆菌表达文库中的一个cDNA有较高的同源性。  相似文献   

Simple sequence repeats as useful resources to study transcribed genes of cotton   总被引：12，自引：0，他引：12  

Sukumar Saha  Mehmet Karaca  Johnie N. Jenkins  Allan E. Zipf  O. Umesh K. Reddy  Ramesh V. Kantety 《Euphytica》2003,130(3):355-364

Microsatellites or Simple Sequence Repeats(SSRs) are informative molecular genetic markers in many crop species. SSRs are PCR-based, highly polymorphic, abundant, widely distributed throughout the genome and inherited in a co-dominant manner in most cases. Here we describe the presence of SSRs in cDNAs of cotton. Thirty one SSR primer pairs of 220 (∼14%) tested led to PCR amplification of discrete fragments using cotton leaf cDNA as template. Sequence analysis showed 25% of 24randomly selected cDNA clones amplified with different SSR primer pairs contained repeat motifs. We further showed that sequences from the SSR-containing cDNAs were conserved across G. barbadense and G. hirsutum, revealing the importance of the SSR markers for comparative mapping of transcribed genes. Data mining for plant SSR-ESTs from the publicly available databases identified SSRs motifs in many plant species,including cotton, in a range of 1.1 to4.8% of the submitted ESTs for a given species. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

New strategies for increasing heterozygosity in crops: Vicia faba mating system as a study case     

M. J. Suso  Lawrence Harder  M. T. Moreno  Fouad Maalouf 《Euphytica》2005,143(1-2):51-65

Our research assesses the feasibility of using artificial selection on pre-mating floral traits to modify the mating system of faba bean (Vicia faba). This analysis considered two synthetic populations, which were derived from different genetic pools and had undergone five years of multiplication. For these populations, we identified floral and inflorescence traits that influence outcrossing per plant and examined the relative importance of these traits in governing yield. Codominant isozyme loci and the mixed-mating model were used to estimate the multilocus female outcrossing rate. A maternal half-sib design was used to evaluate the additive genetic component of floral and inflorescence traits, yield and yield components. Multiple regression was used to assess the effects of floral and inflorescence traits on outcrossing and yield and components of yield. The two populations exhibited mixing mating. Self-fertilization appears to result from the action of pollinating bees, so that its incidence could be modified by selection on floral and inflorescence traits that affect pollination. Floral and inflorescence traits affected individual differences in outcrossing unequally, with most variation being associated with the numbers of displayed flowers and inflorescences. Variation among plants in reward traits and in shape, although statistically significant, had limited and inconsistent influences on individual differences in outcrossing. Yield and its components varied strongly with aspects of floral display and, to a lesser extent, floral design, except for seed weight. Overall, our results imply that both outcrossing and yield could be enhanced by selection for plants that produce more inflorescences, each with relatively few flowers.  相似文献   

水稻极度分蘖突变体的分离和遗传初步研究   总被引：8，自引：2，他引：8  

王永胜  王金发等 《作物学报》2002,28(2):235-239

通过EMS诱变处理栽培稻粳灿89(Oryza sative L.indica JX89）种子，从M2代植株中筛选得到一株突变体，其植株形态表现为叶细、色淡、植株矮化和极度分蘖。在将近一年的营养生长过程中，分蘖总数达到2000多个，命名为极度分蘖突变体（Excessive tillering mutant）ext37.ext 37自交所得M3和M4代植株表现同一表型。突变体自交及其与JX89和丰矮占5号（FAZ-5）发杂交F1、F2代结果表明该突变为显性遗传方式，可能涉及两对等位基因。为了观察突变基因对下游基因表达影响的程度，取生长期44天的亲本JX89和突变体ext37的节间分生组织提纯细胞总RNA，进行基因表达谱差异显示分析。结果表明突变体与亲本的基因表达模式有明显的差异，说明可能是处在上游调控基因的突变影响了下游许多基因的表达。目前有关分子生物学的进一步研究正在进行中。  相似文献   

用不同类型的水稻鉴别品种鉴定江苏稻瘟病菌的致病性   总被引：11，自引：0，他引：11  

周益军  程兆榜  范永坚  王金生  陈毓苓  张文荟 《作物学报》2003,29(2):268-273

根据DNA指纹图谱和系谱, 从1999年采集的96个江苏稻瘟菌株中选择44个菌株进行致病性测定. 它们被鉴定为7个生理小种. 用日本清泽系列单基因鉴别品种和LTH近等基因系(NILs)鉴别品种分析, 分别产生27和10个致病类型, CO39 NILs对江苏菌株几乎没有鉴别作用. 分析结果可见供试菌株之间致病性差异极大. 研究表明, 发展包含较多抗病  相似文献   

Analysis of leaf and needle litter decomposition by differential scanning calorimetry and differential thermogravimetry     

U. Reh  W. Kratz  G. Kraepelin  C. Angehrn-Bettinazzi 《Biology and Fertility of Soils》1990,9(2):188-191

Summary Changes in the physicochemical properties of three kinds of litter (Prunus serotina leaves, Carpinus betulus leaves, and Pinus sylvestris needles) were analyzed by differential scanning calorimetry and differential thermogravimetry after decomposition for 12 to 27 months under field conditions. As expected, holocellulose was always decomposed to a larger extent than the corresponding lignin components, leading to an enrichment of lignin in the residue. These lignins were more or less modified depending on the plant species. Moreover, the results suggest that energy-rich crystalline cellulose accumulates during decomposition at the expense of easier degradable amorphous cellulose and hemicelluloses. The quotient Q, from the corresponding calorimetry and thermogravimetry values, was introduced to estimate the specific energy content as a measure for the decomposition of litter components.Dedicated to the late Prof. Dr. W. Kühnelt  相似文献   

利用基因芯片技术筛选棉纤维伸长相关基因   总被引：6，自引：1，他引：5  

李龙云  于霁雯  翟红红  黄双领  李兴丽  张红卫  张金发  喻树迅 《作物学报》2011,37(1):95-104

从回交近交系(backcross inbred lines, BIL)群体中选取纤维长度差异较大的两个系NMGA-062 (33.03 mm)和 NMGA-140 (25.87 mm),利用Affymetrix棉花基因芯片,分析其开花后10 d (DPA, days post anthesis)棉纤维伸长相关基因表达谱。在24 029条转录本中,两材料间差异表达的转录本有7 282条,占总数的30.31%;其中差异表达倍数在2倍或2倍以上的转录本有3 993条,占筛选转录本总数的16.62%,功能分类表明这些转录本主要包括功能预测基因(15.57%)、翻译、核糖体结构相关基因(13.54%)和翻译后修饰、蛋白质转换相关基因(9.29%)3大类。为了验证芯片数据的可信性,8个差异表达显著的基因(Ghi.10655.1.S1_s_at, ACO1, ARF1, SAHH, TUA6, TUA7, β-tub1, β-tub10)被用于实时荧光定量PCR。两种检测手段表现出一致性。随后,利用实时荧光定量PCR对3个与棉纤维相关基因(ARF1, β-tub1, β-tub10)在纤维发育不同时期(5、10、15、20和25 DPA)的表达模式进行了研究,结果表明,3个基因在纤维伸长发育时期(10和15 DPA)大量表达,推测这3个基因可能与棉纤维伸长有重要关系。  相似文献