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1.
马氏珠母贝选育系遗传变异的AFLP分析   总被引:9,自引:0,他引:9  
利用AFLP技术对马氏珠母贝两个选育系DDS-G1和JCS-G1及大亚湾养殖群体(DDC)进行了遗传变异分析.5对选择性扩增引物共扩增谱带265条,DDC的多态位点比率为79.25%,DDS-G1为73.58%,JCS-G1为75.85%.两个选育系的单态位点明显增加,而Shannon's遗传多样性指数和Nei's基因多样性有所下降.三个组间的遗传距离为0.1615~0.2744,两个选育系间的遗传距离较大.研究结果表明,经过一代的选择,马氏珠母贝选育系的遗传结构和遗传多样性已发生改变,AFLP标记能够有效地监测选育系的遗传变异.  相似文献   

2.
牙鲆GH基因外显子多态性与生长性状关系的初步研究   总被引:7,自引:0,他引:7  
以一个牙鲆养殖群体中的100个个体为实验材料,根据其生长激素(GH)基因的五个外显子序列设计引物,进行PCR扩增,通过SSCP分析技术对其进行检测,结果表明该群体生长激素基因的第四个外显子存在多态性.共检测到两种基因型,其中AA型个体占88%,AB型个体占12%;DNA测序结果表明,AB型在第1763位发生碱基突变,c→t,与AA型同源性达到99%,同时发现不同基因型的个体在体重和头长上表现出显著的差异(P<0.05).上述结果表明利用PCR-SSCP技术可以检测到牙鲆生长激素基因外显子部分存在序列遗传多态性,且该多态性与其生长的某些性状具有一定的连锁关系,为将来进行标记辅助选育奠定了基础.  相似文献   

3.
水产生物技术发展战略研究   总被引:3,自引:0,他引:3  
本文从水产养殖生物基因组测序、遗传连锁图谱绘制、重要经济性状相关分子标记/基因筛选、基因组编辑、基因组选择以及细胞培养与种质冷冻保存等方面综合介绍了水产生物技术的发展现状,并深入分析了水产生物技术研究中存在的主要问题,诸如基因功能分析平台不完善,抗病与性控育种技术研究滞后,基因组编辑与全基因组选择技术刚刚起步等。同时,围绕上述主要问题,提出了水产生物技术亟待突破的关键技术,并建议"十三五"期间设立重点研究计划专项,深入开展水产动物基因组资源开发与利用、重要经济性状遗传解析以及水产生物信息大数据平台构建等。  相似文献   

4.
中国对虾人工选育快速生长群体不同世代间的AFLP分析   总被引:12,自引:0,他引:12  
利用7对AFLP引物组合检测了中国对虾连续五代选育群体基因组DNA的遗传结构,根据AFLP分析结果计算了选育世代群体间的遗传相似系数和遗传距离.结果表明,AFLP标记表现出较高的多态检测效率,7对引物共产生500余条带,平均每对引物组合检测到33.7个多态性标记,平均杂合度为0.0854~0.1025,非常适合于遗传多样性分析.结果显示,随着选育世代的增加,选育群体的遗传多样性呈现下降趋势,但随着选育时间的延长,群体之间的分化逐渐降低,群体的遗传结构开始趋于稳定,成为一个品系.  相似文献   

5.
水产遗传育种与水产种业发展战略研究   总被引:2,自引:0,他引:2  
20多年来,随着水生生物学和生物技术的发展,我国在水产遗传育种与种业方面取得了诸多进展,但也面临着机遇和挑战。本文围绕种质资源保存与利用、遗传机制解析与功能基因挖掘、优良性状新品种选育、水产种业建设等,开展国内外遗传育种现状对比分析研究,分析了当前存在的一些问题,提出未来特别是"十三五"期间水产遗传育种科技发展目标和重点任务。  相似文献   

6.
AFLP分子标记构建中国对虾遗传连锁图谱的初步研究   总被引:29,自引:1,他引:28  
利用AFLP分子标记结合“拟测交”策略,以中国对虾的单对杂交亲本及其F1代为作图群体,应用MAPMAKER EXP/3.0软件,分别构建了中国对虾雌、雄的遗传连锁图谱。在中国对虾的雄性连锁图谱中,74个标记组成了5个连锁群(遗传标记数量大于3)、7个三联体、13个连锁对,总图距为951.5eM,最大连锁群的长度为206.2eM,最短的为7.4eM,标记间的平均距离为12.8eM;雌性连锁图谱中,由66个标记组成的5个连锁群,4个三联体,13个连锁对,总图距为712.7eM,连锁群的长度介于7.7eM~128.2eM之间,标记间的平均距离为10.7eM。估算的中国对虾基因组总长度为2000eM,所构建的连锁图谱分别覆盖了基因组长度的47.5%和35.6%。中国对虾遗传连锁图谱的构建为分子标记辅助育种、比较基因组作图以及基因定位与克隆创造了条件,并对今后其他海洋生物遗传图谱的构建具有理论价值和实践意义。  相似文献   

7.
针对金属磁记忆技术的焊缝缺陷等级定量化评定这一难题,通过对预制不同缺陷的Q345焊接试件进行疲劳试验,获得焊缝损伤演化临界状态的磁记忆信号特征规律.首次对照X射线定量检测标准和磁记忆检测结果,将焊缝损伤演化状态分为4个等级,即正常状态、应力集中、隐性损伤和宏观损伤.首次引入遗传算法优化的BP神经网络模型对焊缝等级进行磁记忆定量化评价.研究表明,遗传优化的BP网络模型与未优化的BP网络相比,预测结果更加稳定、误差更小,为工程实际中焊缝缺陷等级评定提供新的方法和依据.  相似文献   

8.
微卫星标记技术在大豆遗传作图中的应用   总被引:11,自引:0,他引:11  
根据文献报道的序列有选择地合成了20对SSR引物,在用以遗传作图的两个亲本中进行了扩增,有17对引物的扩增产物具有多态性大小范围为70-300bp。其中扩增产和大小差异小于10-20bp的等位基因可通过4%琼脂糖凝胶电脉分开,介绍了多次眯样和多引物PCR技术。X^2显著性检验证明其符合孟德尔式遗传方式,遗传连锁分析表明其中三个微卫星标记加锁  相似文献   

9.
太空诱变玉米核不育基因的SSR作图   总被引:3,自引:0,他引:3  
为研究太空诱变玉米核不育材料的不育基因所在位点,以雄性不育材料03SRP9×S37(自交系)的F2代群体作为育性调查和SSR作图群体,用玉米第3染色体3.06位点的37对SSR引物进行差异筛选,结果表明分子标记umc1674,umc2076,umc1644,dupssr17,bnlg197,umc2271,umc1951和bnlg1047与不育基因表现为连锁遗传,进一步将不育基因定位在分子标记umc2076和umc1674之间,遗传距离分别为4.4 cM和3.7 cM,并以此为基础构建了核不育基因区间的遗传连锁图,为下一步克隆该基因奠定了基础.  相似文献   

10.
玉米SSR连锁图谱构建及抗纹枯病基因定位   总被引:9,自引:0,他引:9  
以玉米自交系R15 (抗)×4 78(感)的F2 分离群体(2 2 9个单株)为作图群体,构建了包含14 6个SSR标记位点的遗传连锁图谱,覆盖玉米基因组16 6 6cM ,平均图距11.4cM。通过麦粒嵌入法对2 2 9个F2∶4 家系进行人工接种纹枯病菌,并采用相对病斑高(绝对病斑高除以穗位高)划分病级标准进行玉米纹枯病的抗性鉴定。应用复合区间作图法分析抗病QTL(数量性状基因座位)及遗传效应。结果共检测到6个抗性QTL ,分别位于第2、6、10染色体上,与标记Umc2 110、Bnlg16 0 6、Umc2 110、Bnlg15 38、Umc12 5 7和Phi0 5 4连锁,各自可解释表型变异的10 35 %、4 0 9%、8 33%、5 18%、5 12 %和4 18%。这些抗性QTL与控制株高和穗位高的基因之间表现为独立遗传。  相似文献   

11.
The fruit fly (Drosophila melanogaster) is an extensively used and powerful, genetic model organism. However, chemical studies using individual flies have been limited by the animal's small size. Introduced here is a method to sample nanoliter hemolymph volumes from individual adult fruit-flies for chemical analysis. The technique results in an ability to distinguish hemolymph chemical variations with developmental stage, fly sex, and sampling conditions. Also presented is the means for two-point monitoring of hemolymph composition for individual flies.  相似文献   

12.
The flow shop scheduling problem with blocking has important applications in a variety of industrial systems but is under-represented in the research literature. In this paper, a modified fruit fly optimisation (MFFO) algorithm is proposed to solve the above scheduling problem for makespan minimisation. The MFFO algorithm mainly contains three key operators. One is related to the initialisation scheme in which a problem-specific heuristic is adopted to generate an initial fruit fly swarm location with high quality. The second is concerned with the smell-based search in which a neighbourhood strategy is designed to generate a new location. To further enhance the exploitation of the proposed algorithm considered, a speed-up insert-neighbourhood-based local search is applied with a probability. Finally, the last is for the vision-based search in which an update criterion is proposed to induce the fruit fly into a better searching space. The simulation experimental results demonstrated the efficiency of the proposed algorithm, in spite of its simple structure, in comparison with a state-of-the-art algorithm. Moreover, new best solutions for Taillard’s instances are reported for this problem, which can be used as a basis of comparison in future studies.  相似文献   

13.
对遗传算法(CA)的交叉和变异操作进行改进,提出利用改进遗传算法(ICA)和函数连接型人工神经网络(FLANN)相结合实现加速度传感器的动态建模的新方法。该方法利用加速度传感器的动态标定数据,采用IGA和FLANN相结合搜索和优化动态模型参数。文中介绍动态建模原理以及算法,给出用IGA和FLANN相结合建立的加速度传感器动态数学模型。结果表明:上面提出的动态建模方法既保留了CA的全局搜索能力和FLANN结构简单的特点,又具有网络训练速度快、实时性好、建模精度高等优点,在动态测试领域具有重要应用价值。  相似文献   

14.
Drosophila, the fruit fly, is a common model organism in biology; however, quantifying neurotransmitters in Drosophila is challenging because of the small size of the central nervous system (CNS). Here, we develop neurotransmitter quantification by capillary electrophoresis with fast-scan cyclic voltammetry (CE-FSCV) detection, which allows peak identification by both migration time and the cyclic voltammogram, in contrast to traditional amperometric detection which provides no chemical identification. Tissue content of biogenic amine neurotransmitters was determined in a single CNS dissected from a Drosophila larva. Low detection limits, 1 nM for dopamine and serotonin, 2.5 nM for tyramine, and 4 nM for octopamine, were achieved using field-amplified sample stacking by diluting the homogenized tissue with percholoric acid and acetonitrile. Two different strains of wild-type flies, Oregon R and Canton S, have similar dopamine and serotonin levels but different octopamine content. When flies are fed NSD-1015, which inhibits dopamine decarboxylase (Ddc) a synthesis enzyme in the dopamine and serotonin pathways, dopamine significantly decreases by 52%. A genetically altered driver line, Ddc-GAL4, had lower serotonin and dopamine content as did w(118) flies. When the Ddc-GAL4 line was used to produce flies overexpressing the serotonin synthesis enzyme tryptophan hydroxylase (Ddc-GAL4;UAS-Trh), the serotonin tissue content was greater than for Ddc-GAL4 but not significantly different than the wild-type. These results show that CE-FSCV is useful for monitoring the impact of genetic and pharmacological manipulations on the content of multiple neurotransmitters in a CNS from a Drosophila larva.  相似文献   

15.
粉煤灰机械研磨后热学性质变化的研究   总被引:1,自引:0,他引:1  
研究了粉煤灰经过机械研磨后的热学性质的变化。不同的机械研磨方式 ,粉煤灰的热学性质表现不一样 ;对于同一种机械研磨方式 ,不同粉煤灰的热学性质有一些共同之处。粉煤灰机械处理之后热学活性的增加 ,机械热效应在研磨中起重要作用。DTA峰温的提前 ,实质是粉煤灰颗粒在机械能的作用下位能升高 ,不稳定趋势加大  相似文献   

16.
聚苯胺(PAn)作为电流变材料具有响应快、屈服应力大的特点,但因其良好的导电性能导致漏电击穿现象发生,为了进一步增加PAn的悬浮稳定性,引入了粉煤灰漂珠(FAFB),BaTiO_3作为经典的电介质材料也引入其中以进一步提高材料的介电性能。采用逐层包覆的思路,利用溶胶-凝胶法在漂珠表面包覆BaTiO_3,获得FAFB@BaTiO_3,再利用原位聚合法制备以FAFB@BaTiO_3为核、PAn为壳的结构复合材料即FAFB@BaTiO_3@PAn。利用FTIR、XRD和SEM对材料的结构与形貌进行分析,借助四探针技术和LCR数字电桥对材料的导电与介电性能进行分析,利用自组装电流变仪进行了电流变特性测试,考察了7d内的悬浮稳定性能。结果表明:BaTiO_3、PAn确实发生了逐层包覆,且电导率、介电常数、介电损耗和剪切应力均符合复合效应规律,介于PAn与FAFB@BaTiO_3之间,其中,剪切应力可达675Pa(电场强度为3.0kV/mm);漏电现象得到缓解,击穿电压提高了20%;比较悬浮稳定性发现,7d后FAFB@BaTiO_3@PAn悬浮率仍为82%。  相似文献   

17.
The behaviour of Al in MSW incinerator fly ash during thermal treatment   总被引:3,自引:0,他引:3  
Fly ash from municipal solid waste (MSW) incinerators contains leachable metals, including potentially hazardous heavy metals. The metal content of the fly ash can be reduced by thermal treatment, which vaporizes the volatile metal compounds. After heat treatment of fly ash at 1000 degrees C for 3 h, less metal was able to be leached from the thermally treated ash than from the ash without thermal treatment. Al and Cr were the exceptions. These metals were more soluble in the ash that had been thermally treated. This paper focuses on the leaching behaviour of Al only. Both simple and sequential extraction leaching tests showed that the leachable Al for the heat-treated fly ash is about twice that of the untreated fly ash. The sequential test further revealed that (i) the majority of the leachable Al is associated with Fe-Mn oxides in the fly ash, and (ii) most of the unleachable Al resides in the silicate matrices of the heat-treated and untreated fly ash. Pure chemicals, Al(2)O(3), CaO and CaCl(2), simulating the relevant ingredients in the fly ash, were used for studying their reactions at 1000 degrees C. The aluminum compounds were identified by X-ray Diffraction (XRD). Two new chemical phases produced by the thermal treatment were identified; Ca(AlO(2))(2) and 12CaO.7Al(2)O(3). Their formation suggests a mechanism whereby thermal treatment of fly ash would produce more soluble Al.  相似文献   

18.
In this paper, investigations were undertaken to formulate the properties of fly ash-calcium sulfoaluminate (CSA) cement matrix by blending MSW fly ash with CSA cement. The compressive strength, pore structure, hydration phases, and leaching behavior of Zn and Pb doped MSW fly ash-CSA cement matrices were determined by XRD, MIP, DSC, FTIR, EDX, TCLP leaching test and other experiments. The results showed that the addition of MSW fly ash to form fly ash-CSA cement matrix reduced the compressive strengths of matrices and made the pore distribution of matrices coarser, compared to that of pure CSA cement matrix. However, fly ash-CSA cement matrix could effectively immobilize high concentration of heavy metal such as lead and zinc with much lesser leaching of TCLP. Besides ettringite AFt, Friedel phase was a new hydration phase formed in the matrix. The formation of these hydration phases was responsible for huge reservoir of heavy metal stabilization by chemical fixing. Therefore, it could be postulated that MSW fly ash-CSA cement matrix was a potential new constituent of S/S matrix for high concentration of heavy metals such as Zn and Pb ions.  相似文献   

19.
一种针状铁素体钢热轧板材的结构与力学性能   总被引:5,自引:0,他引:5  
在透射电镜(TEM)下观测了一种管线用针状铁素体钢热轧板材的显微组织并研究了力学性能.结果表明,这种管线用针状铁素体钢热轧板材具有较优良的强韧性能,其显微组织与焊接组织在形态上有很大的差异.管线用针状铁素体钢热轧板材中有明显界面的板条束或针状片条束;没有明显界面的板条束或针状片条束,可根据条状物或岛状物的有方向性的线状分布依稀辨别界面的存在;板条或针状片条与非等轴晶共存等多种不同形态,并不象焊接组织那样通常是单一的针状片条束或板条束形态.  相似文献   

20.
利用萘升华传质/传热比拟实验方法,研究了每管六涡扁长椭圆翅片管换热器换热板芯在三角翼形涡产生器不同翼高时的换热和阻力特性,分析了涡产生器翼高的变化对错排椭圆翅片管换热器传热与阻力特性的影响,为该型换热器设计提供了一定的理论依据.  相似文献   

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