首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 63 毫秒
1.
用RFLP标记分析甘蓝型油菜的遗传多样性   总被引:36,自引:2,他引:36  
孟金陵  钱秀珍 《遗传学报》1996,23(4):293-306
以甘蓝型油菜的28个基因组探针和两种限制性内切酶对包括46个中国品种、9个欧洲品种在内的59个甘蓝型油菜品种(系)的RFLP标记进行了分析。在放射自显影胶片上,共检测到410条具多态性的分子杂交带,表明甘蓝型油菜中存在着极为丰富的遗传变异。聚类分析结果表明,在相似性为45%的水平上,可把中国甘蓝型油菜划分为6组:胜利油菜组、跃进油菜组、中油821组、远缘种质组、优质油菜组和变异不详组。欧洲冬油菜与以上6组存在着较显著的遗传距离。主成分分析的结果与上述分组较为一致。以上结果表明,对于扩大中国甘蓝型油菜的遗传基础,欧洲冬油菜无疑是一个重要的种质资源。另一方面,用典型的中国甘蓝型油菜与欧洲冬油菜配制的杂交种,较易产生强大的杂种优势。从对已进行了染色体定位的61条放射自显影带的分析看,无论是上述分组内,还是分组间,RFLP的相对差异均主要表现在A基因组中。讨论了致使A基因组遗传变异较大的可能因素。  相似文献   

2.
云南绵羊线粒体DNA遗传多态性研究   总被引:31,自引:0,他引:31  
本研究用12种识别六碱基的限制性内切酶对来自云南省3个地方绵羊品种11个样本的线粒体DNA(mtDNA)进行了限制性片段长度多态性分析(RFLP),结果表明,云南绵羊群体平均核苷歧异度为0.086%,平均遗传距离为0.00 4,说明mtDNA变异度很低,遗传多样性贫乏,提示云南绵羊可能起源于同一个共同祖先;昭通绵羊与德钦绵羊距离较远,大约分歧于30万年前,德钦绵羊与腾冲绵羊大约分歧于11万年前,而腾冲绵羊与昭通绵羊也于18万年前发生分歧。 Abstract:mtDNA from 11 sheeps samples of Deqin,Zhaotong and Tengchong in Yunnan province was analyzed with 12 restriction endonucleases.14 restriction types were observed which could sorted into 3 haplotypes.The estimated number of nucleotide substitutions per site(π)in Yunnan sheep was 0.086% and the mean genetic distance(P) was 0.004.This results might show a pattern of single origin of Yunnan sheep.Divergencetime of the native sheep flocks from three districts of Yunnan were estimated on the mean rate of sequence divergence of 0.01 per million years in mtDNA.  相似文献   

3.
烟草主要数量性状的遗传效应分析   总被引:7,自引:0,他引:7  
许明辉  王孟宇  龙文虹 《遗传》2000,22(6):395-397
利用红花大金元×青梗,红花大金元×中烟14号P1、P2、F1、F2、B1、B2 6个世代资料对7个农艺性状和4个品质性状进行了基因效应分析。结果表明,性状均不符合简单的加性-显性遗传模型,多数性状加性效应显著而显性效应不显著,在3种互作效应中,所有性状至少有一种显著。互作效应普遍存在,是烟草性状杂种优势表现的主要原因之一。 Abstract:Two tobacco F1 hybrids,F2s,backcrosses B1s and B2s and their parents P1 and P2 were used to estimate the gene effects for 7 agronomic and 4 quality characters.The additive-dominance genetic model was not fit for all characters.The additive effects and the epistatic effects of most characters were significant,but the dominant effect not.The epistatic effects could not be ignored in tobacco breeding.They were one of main causes of heterosis for most characters.  相似文献   

4.
中国甘蓝型油菜遗传多样性的RAPD分子标记   总被引:24,自引:0,他引:24  
本文利用RAPD方法和统计学分析,对我国7省市和国外引进的总计40份甘蓝型油菜品种的遗传多样性进行了研究。结果表明,40个品种的甘蓝型油菜存在着广泛的遗传变异,根据RAPD指纹图谱,通过在DNA分子水平上的聚类分析可以将它们分为3大类群,反映出这些品种之间的亲缘关系,并对如何引进甘蓝型油菜资源进行了初浅的讨论。  相似文献   

5.
玉米籽粒性状的遗传效应分析   总被引:5,自引:0,他引:5  
李玉玲  张泽民  许自成  席章营 《遗传》2000,22(3):133-136
采用二倍体胚和三倍体胚乳种子遗传模型及其分析方法,以5个玉米自交系及其配制的F1,F2,BC1,BC2世代为材料,研究5个玉米种子性状的胚直接效应、胚乳直接效应、母体效应和细胞质效应。分析结果表明,除粒宽外,各性状的遗传同时由细胞质效应和胚、胚乳、母体基因效应所控制,百粒重主要受胚乳和母体效应的影响,粒长的遗传以母体效应为主,粒宽和粒厚以胚乳效应为主。各部位籽粒百粒重的胚乳直接加性效应与母体加性效应的协方差达到显著或极显著水平,其余性状的胚、胚乳直接效应与母体效应间的协方差均不显著,通过母体植株的遗传表现可以对这些性状进行有效的选择。S22 是改良百粒重的优良亲本。 Abstract:The embryo,endosperm and cytoplasm effects of seven seed traits were studied by genetic model for diploid embryo and triploid endosperm plant seeds using five inbreds and their F1, F2, BC1 and BC2 generations. The estimates of genetic variance components indicated that the inheritance of all other kernel traits was controlled by the four effects except kernel width. The 100?kernel weight was mainly controlled by endosperm and maternal effects , and kernel length was controlled by the maternal effects,while endosperm conrrolled kernel width and kernel thickness. Except the significant or highly significant covariances between the endosperm direct additive and maternal additive effects for 100-kernel weight,all other traits between the embryo or endosperm direct effect and the maternal were not significant. So,maize inbreds could be developed by direct selection based on maternal plants for these traits. S22 was the best inbred of the improvement for kernel weight in this study.  相似文献   

6.
指出了Nei氏遗传相似度仅仅是用来描述两个二进制变量差异或相似程度的一种距离系数或相似系数,与个体间亲缘程度没有必然联系.根据亲缘系数的定义,提出新的遗传相似度计算公式即rA(x,y)=(2N2xy)/(NxNy)或rA(x,y)=(N2xy)/(NxNy).并通过实例验证了该公式可用于判断个体间亲缘程度方面。 Abstract:Nei's genetic similarity was only described as a kind of distance coefficient for binary system variables and it have not positive connection with the relationship between individuals.According to the definition of the relationship coefficient,a new formula which is about genetic similarity is put forward as following:rA(x,y)= It is verified by an example that this formula can be used to judge the relationship between individuals.  相似文献   

7.
松属植物遗传多样性研究进展   总被引:17,自引:0,他引:17  
李斌  顾万春 《遗传》2003,25(6):740-748
研究松属遗传多样性的方法涉及表型、同工酶、染色体、DNA等多层面。 松树表型性状变异广泛,其不同树种不同性状的遗传力(或遗传率)均存在差异。到目前为止,同工酶仍是检测松树遗传多样性的最常用方法,一般而言,松属树种群体内等位酶多样性程度高,群体间分化较低,但各树种的情形也不尽相同。松属树种染色体水平的变异很低,其核型高度一致。核DNA组较一般阔叶树大,遗传多样性丰富,但叶绿体等质体DNA则多样性较低。影响遗传多样性的因素很多,其中自身的交配系统和外部的生长环境是影响它的两个主要因素。最后,回顾了松树的起源及其遗传多样性保护策略等方面的研究。 Abstract:The ways of probing genetic diversity of pines involve many aspects,such as morphology,chromosome,isozyme,DNA,etc.The phenotypic characteristics in pines vary widely and the differences of inheritability(h2) are obvious among characteristics and among species.Up to now,isozyme is still the most common means to measure genetic diversity of pines.Generally,there are high allozyme diversity within populations and low differentiation coefficient among populations,but differences exist between species in Pinus.The variations of chromosome among pines are very low and the karyotypes of pines are consentaneous,but the genomes of pines in cell nucleus are much larger than that of broadleaves.Diversity of pines are abundant at nucleus DNA level but are poor at plastid DNA level,such as ctDNA.There are many factors that will affect genetic diversity of pines,in which mating system and environment are two main factors.Finally,we reviewed the research on origin of Pinus and conservation strategy of genetic diversity,etc.  相似文献   

8.
蚕豆主要数量性状的遗传主成份和数量分类   总被引:6,自引:0,他引:6  
对50个蚕豆品种的7个数量性状进行了遗传主成份分析, 初步提出了评选蚕豆品种的遗传主成份标准,并筛选出18个综合性状优良的亲本品种。测定了50个蚕豆品种的遗传距离, 根据遗传距离大小,将50个蚕豆品种聚类为2群、 3类、9组。分类结果指出,蚕豆品种的遗传距离大小与地理差异有些似有一定关系,但在总体上,二者间无必然联系。 Abastract:Analysis of major Genetic component analysis was performed for 7 quantitative characters of 50 faba bean lines and according to the analysis,18 lines were selected as parents.The 50 lines were classified into 2 subpopulations,3 types and 9 groups according to their genetic distance.The results showed that there was seemly a correlation between geographical distribution and genetic distance,nevertheless most lines within the same cluster were close in genetic distance but far in geographic sites.  相似文献   

9.
内蒙古白绒山羊若干数量性状遗传参数的研究   总被引:10,自引:2,他引:10  
本研究应用女母回归法、公畜内女母回归法、半同胞相关法和单元内半同胞相关法对内蒙古阿尔巴斯白绒山羊的产绒量、绒厚、毛长、体重、绒伸直长度和细度等六个性状的遗传参数进行了估测。结果表明:(1)绒量遗传力介于0.26~0.45之间;绒厚遗传力介于0.33~0.56之间;毛长遗传力介于0.23~0.32之间;体重的遗传力介于0.16~0.36之间;绒伸直长度遗传力为0.24;绒细度的遗传力为0.14。(2)产绒量与绒厚、绒厚与毛长、长度与绒厚、长度与毛长的遗传相关分别介于0.33~0.79、0.51~0.69、0.38~0.60、0.74~0.90之间,存在较强的正向遗传相关;绒量与毛长、绒量与体重、绒厚与体重、细度与绒厚、细度与绒量、细度与体重的遗传相关分别为0.11~0.38、0.06~0.17、0.15~0.36、0.02~0.11、0.24~0.35、0.13~0.32之间,存在较弱的正向遗传相关;毛长与体重、长度与绒量、长度与体重、长度与细度、细度与毛长之间的遗传相关介于-0.14~-0.28、-0.09~-0.20、-0.18~-0.23、-0.27~-0.31、-0.17~-0.28之间,存在中等偏弱的负向遗传相关。(3)绒量、绒厚、毛长、体重的重复率分别为0.42、0.27、0.59、0.18。 Abstract:Daughter-dam regression, daughter-dam regression wit hin sire, half-sib correlation and intro-unit half?sib correlation were used in the study to estimate genetic parameters for several traits of Albas type of In ner Mongolia cashmere goats, Traits included in this paper were cashmere yield ( CY),cashmere thickness(CT),staple length(SL),body eight(BW),cashmere stretched length(CSL) and cashmere fineness(CF).The results showed: (1)Heritabilities for CY,CT,SL and BW ranged between 0.26 and 0.45,between 0.33 and 0.56, between 0.23 and 0.32 and between 0.16 and 0.36 respectively; Heritabilities for SL and CF were 0.24 and 0.14 respectively.(2)Genetic correlations between CY and CT,between CT and SL ,between SL and CT and between CST and SL ranged 0.33~0. 79, 0.51~0.69, 0.38~0.60, and 0.74~0.90,respectively,and they belonged to high positive one;Genetic correlations between CY and SL, between CY and betw een CY and BW,between CT and BW, between CF and CT, between CF and CY and betwe en CF and BW ranged 0.11~0.38, 0.06~0.17,0.15~0.36, 0.02~0.11, 0.24 ~0.35 and 0.13~0.32,respectively, and they belonged to low positive correla tion;Genetic correlations between SL and BW, between SL and CY,between SL ?and BW, between? SL and CF and between CF and SL ranged -0.14~-0.28, -0.09~-0 .20, -0.18~-0.23,-0.27~-0.31,and -0.17~-0.28,respectively,and they belonged to low negative correlations.(3)Repeatabilities for CY,CT,SL and BW were 0.42,0.27,0.59 and 0.18,respectively.  相似文献   

10.
栓皮栎天然群体SSR遗传多样性研究   总被引:14,自引:0,他引:14  
徐小林  徐立安  黄敏仁  王章荣 《遗传》2004,26(5):683-688
利用微卫星(SSR)标记对我国4个省内的5个栓皮栎(Quercus variabilis Bl.)天然群体的遗传多样性进行了研究。16对SSR标记揭示了栓皮栎丰富的遗传多样性:等位基因数(A)平均8.4375个,有效等位基因数(Ne)平均为5.9512个,平均期望杂合度(He)0.8059,Nei多样性指数(h)为0.8041。栓皮栎自然分布区中心地带的群体具有较高的遗传多样性,而人为对森林的破坏将降低林木群体的遗传多样性。栓皮栎群体的变异主要来源于群体内,群体间分化较小,遗传分化系数仅为0.0455。此外,栓皮栎群体间的遗传距离与地理距离之间存在显著的正相关。这些遗传信息为栓皮栎遗传多样性的保护和利用提供了一定依据。Abstract: Genetic diversity of five Quercus variabilis natural populations in four provinces of China was studied with microsatellite (SSR) markers. A relatively high level of genetic diversity was detected in Q. variabilis species with 16 polymorphic microsatellite loci. Average number of alleles (A) and effective number of alleles (Ne) were 8.4375 and 5.9512 respectively. The mean expected heterozygosity (He) was 0.8059 and Nei diversity index (h) was 0.8041. Higher diversity was found with the populations from the central range of the species in contrast to those from peripheral areas and human activities might decrease the genetic diversity of populations. The majority of genetic variation occurred within populations, which could be concluded from the low coefficient of genetic differentiation (Fst=0.0455). In addition, significant correlation was found between geographical distance and genetic distance. All these results present a basis to the conservation and utilization of genetic diversity of Quercus variabilis.  相似文献   

11.
茎瘤芥主要数量性状遗传力和遗传进度的初步研究   总被引:4,自引:0,他引:4  
以23个茎瘤芥地方品种为试材估算了15个性状遗传力、遗传进度及遗传变异系数。结果表明各性状遗传力从大到小顺序为营养生长期、瘤茎膨大期、茎/叶、菜皮百分率、瘤茎产量、叶宽、瘤茎横径、出苗至瘤茎膨大始期、株鲜重、瘤茎纵径、叶长、菜形指数、开展度、瘤茎空心率、株高。瘤茎空心率、茎/叶、菜皮百分率和瘤茎产量的遗传变异较大,具有较大的选择潜力。在5%的选择率下,可获得较大的遗传进展。综合试验结果认为,瘤茎膨大期、营养生长期、茎/叶宜在早代进行一次性单株选择,菜皮百分率、瘤茎产量、叶宽等性状可适当加强早代选择。  相似文献   

12.
Combining ability and heritability of bolting character of four non heading Chinese cabbage inbred lines were analyzed using Griffing diallel cross I. The results showed that the general combining ability of inbred lines M11 1 2 and M11 1 4 were better, with as bolting resistant potential parental material. The broad sense heritability and narrow sense heritability of bolting character were 9742% and 9141% respectively, and mainly affected by additive genes.So,the selection of bolting characters in non heading Chinese cabbage was effective in early generations.  相似文献   

13.
Mathematical expressions, to investigate the effects of mederate departure from normality assumption on the point estimate and on the probability of getting a negative estimate of genetic heritability, in a balanced situation, have been derived. The numerical results show that the point estimate is over sensitive whereas the probability of a negative estimate is insensitive to this violation.  相似文献   

14.
目的:用经典的双生子设计探讨遗传因素对青少年身高、体重、体质指数(BMI)等体型指征的影响程度。方法:从青岛市双生子库中选择自愿参加本研究的362对11-19岁双生子,测量身高、体重。同性别的双生子通过16个多态标记进行卵型鉴定,在此基础上,应用Mx软件构建结构方程模型分析计算遗传度。结果:对362对有效双生子数据进行分析,其中同卵双生子194对,异卵双生子168对,身高的最佳拟合模型ACE模型,体重和BMI的最佳拟合模型为AE模型。调整年龄性别后,身高的遗传度为66%,体重的遗传度为84%,体质指数的遗传度为75%。结论:在青少年体型指征的相关指标中,身高、体重、BMI受遗传因素影响都较大。  相似文献   

15.
16.
Summary The heritability, h I 2 , of a linear combination of phenotypes, I, when defined as the ratio of the variance of the genetic index, g 2 *, to the variance of the index, I 2 , is shown to be different from the square of the correlation, r HI 2 , between the index and an arbitrary linear combination of genetic effects, H. The gain in H fror selection on I is shown to be proportional to h I 2 . bHg for any index.Approved for publication as Journal Article No. 183-76 of the Ohio Agricultural Research and Development Center, Wooster, Ohio 44691.  相似文献   

17.
CL系列甘蔗亲本的遗传力及配合力分析   总被引:2,自引:0,他引:2  
为探讨CL系列甘蔗品种作杂交亲本的遗传特点,采用3×3不完全双列杂交(NCⅡ)遗传设计,估算了7个产量和品质性状的遗传方差、一般配合力(GCA)和特殊配合力(SCA)。结果表明:锤度的遗传主要受母本加性基因效应控制,株高的遗传主要受父母本加性基因控制,而锤重的遗传主要受非加性基因效应所制约;CL83-1163作为母本,糖分配合力高,且能把高糖特性传递给后代,CL88-4730为父本,产量和品质性状的配合力大,其杂交后代表现高产高糖;根据配合力总效应(TCA),综合表现好的组合有CL83-1364×CL88-4730、CL83-1900×CL84-3152、CL83-1163×CL88-4730,可用于今后的甘蔗有性育种计划。  相似文献   

18.
The aim of this investigation was to quantify the relative contributions of genetic and environmental influences to the observed variability of permanent tooth size in a group of Australian Aboriginals. Tooth size data were obtained from dental casts of Aboriginals living at Yuendumu in the Northern Territory of Australia. The custom of polygyny practised by these people enabled the analysis of associations between full-siblings and half-siblings. Phenotypic variability of tooth size was partitioned into four variance components; between sides, between fathers, between mothers and between offspring. From these components, the relative genetic and environmental contributions were quantified and heritability estimates for tooth size derived. Additional estimates of heritability were obtained by regression analysis from a small sample of parent-offspring data. Results of the analyses suggested that about 64% of the total variability of permanent tooth size could be attributed to genetic factors, while a further 6% was due to common environment. Although the findings confirm a relatively strong genetic component, they emphasise the importance of non-genetic influences in the determination of tooth size variability.  相似文献   

19.
用胶原酶法分离胰岛细胞、超速离心法提取中国地鼠胰岛和肝脏细胞膜蛋白,SDS电泳、WesternBlotting分离GLUT后,应用GLUT2抗体免疫结合法测定GLUT的含量与分子量,同时测定了动物血糖、尿糖和血浆胰岛素的含量、显微镜下直接计数了胰岛细胞总数。结果表明:NIDDM发病后,自发NIDDM中国地鼠胰岛细胞GLUT含量减少,与GLUT2抗体反应明显减弱,但肝脏GLUT无明显变化。胰岛细胞总数发病前后大体一致。而血糖、尿精及血浆胰岛素浓度明显升高。  相似文献   

20.
Three new improved regression estimators of heritability viz. modified range restricted estimator, minimum quadratic loss estimator and minimax linear restricted estimator are proposed. In addition, these estimators are illustrated and compared numerically with the existing restricted estimator based on linear stochastic constraint.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号