水稻功能基因标记遗传距离与杂种优势的相关性研究

 利用与产量性状相关的功能基因标记分析了29个杂交水稻组合亲本间（18个不育系和11个恢复系）的遗传差异,结合29个亲本所配组合（47个）的F1表现,研究了功能基因标记遗传距离与杂种优势的相关性。结果表明,功能基因标记遗传距离与产量杂种优势呈显著正相关（r=0.29*）,而与其他主要产量构成因素的杂种优势相关不显著。说明功能基因标记有可能应用于杂交水稻杂种优势预测,但得到的相关系数偏小,还不足以预测杂种优势。     

RFLP标记水稻遗传距离及其与杂种优势的关系

用12个水稻亲本按NCⅡ设计配组32个F1杂种,以汕优63为对照,研究播始历期、株高、穗长及产量因素等8个性状的杂种优势;并以12个亲本为DNA样品来源,通过RFLP分析基因组DNA的多态性,由RFLP数据计算的Nei's遗传距离创建聚类树状图,探索利用RFLP标记水稻亲本遗传距离预测杂种优势的可能性.聚类分析结果表明,籼稻和粳稻容易被分开,普通粳稻又容易与光壳稻、爪哇稻分开.F1杂种8个性状的杂种优势显示,每穗总粒数的优势最强,中亲优势平均为33.46%,竞争优势平均为23.10%.播始历期、株高、穗长、有效穗等4个性状的中亲优势和竞争优势均表现为粳×粳＜粳×偏粳＜粳×籼.每穗总粒数的中亲优势也表现上述趋势,而竞争优势则是粳×粳＜粳×籼＜粳×偏粳.播始历期、株高、穗长的中亲优势和竞争优势与遗传距离之间均达极显著相关.有效穗和每穗总粒数的中亲优势与遗传距离之间达极显著相关,而竞争优势与遗传距离之间的相关系数也较大,分别达到0.33和0.23.根据聚类图发现普通粳稻亚群内杂种优势较弱,亚群间即生态群间的杂种优势较强,可以利用光壳稻、爪哇稻选育不同生态群方向的恢复系和不育系,配组超强优势的杂交稻组合.     

小麦杂种优势群研究V.微卫星分子标记遗传距离与普通小麦和斯卑尔脱小麦种间杂种优势的关系

通过对普通小麦与斯卑尔脱小麦和普通小麦品种间两组亲本微卫量分子标记遗传距离了30个普通小麦与斯卑尔脱小麦种间双列杂交杂种和20个普通小麦品种间双列杂交杂种优势及亲本配合力的测定,研究了微卫星分子标记遗传距离与杂种优势、F1性状值及组合特殊配合之间的关系。结果表明,普通小麦与斯卑尔脱小麦种间的杂种优势明显高于普通小麦品种间的杂种优势。普通小麦与斯卑尔脱小麦间的平均遗传距离为0.562,普通小麦品种间的遗传距离为0.404,普通小麦与斯卑尔脱小麦种间杂种单株产量平均优势为111.39%,普通小麦品种间杂种的产量优势平均为11.14%。研究发现,在所采用的两组亲本内,遗传距离与所考察的各性状杂种优势没有必然的联系,但当遗传差异从品种间扩大到种间时,遗传距离与各性状杂种优势呈显著正相关。说明利用种间杂交既可以明显扩大亲本间的遗传差异,又可以显著提高小麦的杂种优势潜力。     

利用大豆育成品种的SSR标记遗传距离预测杂种优势的初步研究

以来自6个省市的10个育成品种及其配制杂交的22个F1代为材料，用18个大豆SSR引物对亲本进行检测，探索用亲本间分子遗传距离预测F1代杂种优势的可能性，为大豆杂种优势利用的亲本选配提供参考。结果表明，10个育成品种根据SSR数据可聚为两类，提高F1代的分枝数和单株荚数，选择类内的亲本配制组合要好于选择类间的亲本。大多数具有部分相同遗传背景F1性状的差异显著性和杂种优势随着亲本组合的不同而改变，与遗传距离关系并不密切。F1总体和少数具有部分相同遗传背景的F1百粒重的超中亲、高亲优势与遗传距离存在2次曲线极显著相关，F1总体分枝数的超中亲优势与亲本间遗传距离存在2次曲线显著相关。     

采用SSR标记和表型性状聚类对杂交粳稻亲本的遗传多样性研究

以20个新育成的粳稻BT型不育系和10个恢复系为材料,采用SSR分子标记和表型性状2种聚类方法对杂交粳稻亲本的遗传多样性进行比较研究,并分析这些亲本的遗传差异.结果表明,64对SSR引物在30个亲本中共检测到185个多态性片段,平均每对引物为2.9个,以第11染色体上的平均等位基因数目最多,每个SSR位点的多态性信息含量指数(PIC值)变化范围为0.064～0.844.利用SSR分子标记将30个亲本材料划分为7大类群,其中所有不育系被划分为一群,分类结果与系谱分析基本吻合.表型聚类以10个农艺性状为依据,将供试材料划分为4大类群,不育系和恢复系被聚到不同的类群,群内差异小大.同表型性状聚类相比,SSR分子标记聚类能更准确的揭示亲本之间的遗传差异,是研究亲本遗传多样性的一种较好方法.     

小麦杂种优势群研究 Ⅴ.微卫星分子标记遗传距离与普通小麦和斯卑尔脱小麦种间杂种优势的关系

通过对普通小麦与斯卑尔脱小麦和普通小麦品种间两组亲本微卫星分子标记遗传距离及 30个普通小麦与斯卑尔脱小麦种间双列杂交杂种和 2 0个普通小麦品种间双列杂交杂种优势及亲本配合力的测定 ,研究了微卫星分子标记遗传距离与杂种优势、F1性状值及组合特殊配合力之间的关系。结果表明 ,普通小麦与斯卑尔脱小麦种间的杂种优势明显高于普通小麦品种间的杂种优势。普通小麦与斯卑尔脱小麦间的平均遗传距离为 0 .6 5 2 ,普通小麦品种间的遗传距离为 0 .4 0 4 ,普通小麦与斯卑尔脱小麦种间杂种单株产量平均优势为 111.39% ,普通小麦品种间杂种的产量优势平均为 11.14 %。研究发现 ,在所采用的两组亲本内 ,遗传距离与所考察的各性状杂种优势没有必然的联系 ,但当遗传差异从品种间扩大到种间时 ,遗传距离与各性状杂种优势呈显著正相关。说明利用种间杂交既可以明显扩大亲本间的遗传差异 ,又可以显著提高小麦的杂种优势潜力。     

利用SSR标记和表型性状聚类分析食味优良粳稻多样性

 用SSR分子标记、食味性状、农艺性状3种数据对来自国内外不同地域的食味表现优良的常规粳稻品种（系）进行了多样性分析。72对SSR引物在60份供试材料中检测到290个等位基因变异,以第5染色体上平均等位基因数目最多。大部分食味优良粳稻材料之间的遗传相似性较高,遗传相似系数范围为0600~0924,检测的标记是以3~4个等位基因为主的SSR引物位点。利用SSR标记检测等位基因的材料分群结果表现出一定程度的地域性,江苏省内大多材料可聚为一类,而其他少数及北方粳稻材料多与国外食味优异粳稻品种亲缘关系较近,与其系谱分析结果基本一致。以食味鉴定表型性状为依据,部分产地来源不同而食味优良的材料明显聚为一类,表明遗传基础是决定其食味的主要因素。农艺性状表现与材料来源有一致性,而与食味优良的关系有待进一步明确。     

利用SSR分子标记划分籼型水稻杂种优势群

利用SSR分子标记分析了58份籼稻材料间的多态性,计算了各材料间的遗传距离,并以遗传距离为依据,通过UPGMA法聚类分析,把供试的籼稻材料划分为3个类群。杂种优势分析表明,群间优势大于群内优势,说明利用SSR标记划分籼型水稻杂种优势群是可行的。     

杂交油菜亲本遗传距离分析与杂种优势

选用甘蓝型油菜细胞质雄性不育亲本２４份进行遗传距离的测定，并对亲本的遗传距离与之相对应的Ｆ１产量杂种优势的相关关系进行了探讨。结果表明：亲本遗传距离与杂种优势间存在一定程度的正相关，且遗传距离大的类群间亲本配制的杂交组合其杂种优势大于遗传距离小的类群间和类群内亲本配制的杂交组合。     

小麦亲本间分子遗传距离与F1杂种优势的相关性分析

为了探讨利用小麦亲本间分子遗传距离预测F1杂种优势的可行性，以河南省8个不同类型的小麦品种（系）为材料，分别于2003年和2004年按不完全双列杂交组配28个组合，分析与产量相关的9个性状的F1杂种优势。分别选用均匀分布于小麦21条染色体上的287对SSR引物和33个二核苷酸重复ISSR引物，计算8个亲本间的分子遗传距离．进而分析亲本间分子遗传距离与F1杂种优势表现的相关性。结果表明，SSR和ISSR两种标记估算的遗传距离间相关极显著（相关系数为0．832），表明用两种分子标记对小麦品种进行遗传差异分析的结果是一致的。除株高外，利用两种分子标记计算的亲本间分子遗传距离与F1杂种优势在全部28个组合中相关不显著，而在12个极端组合中相关系数得到较大提高，并在株高、主茎千粒重和千粒重3个性状上相关达到显著或极显著水平，且两年的研究结果一致。这说明亲本间分子遗传距离与F1杂种优势的相关性与材料的选择有关。因此认为利用小麦亲本间的SSR和ISSR遗传距离预测F1的杂种优势还需进一步研究。     

Relationship Between Heterosis and Parental Genetic Distance Based on Molecular Markers for Functional Genes Related to Yield Traits in Rice

The genetic distances among 18 cytoplasmic male sterile lines and 11 restorer lines were analyzed with molecular markers derived from yield-related functional genes.The correlation between parental genetic distance and heterosis was investigated by analyzing the performance of 47 combinations.The results showed that the genetic distance was significantly correlated with yield heterosis(r=0.29*),but not significantly correlated with heterosis for other traits,such as number of effective panicles per plant,se...     

Mapping a Rice Glabrous Gene Using Simple Sequence Repeat Markers

Inheritance analysis and gene mapping of the glabrous trait were conducted using the crosses between a pubescent rice material Chuanxiang 29B (an aromatic elite maintainer line of hybrid rice), and two glabrous rice materials, Lemont and R2 (R2 is a new restorer line of hybrid rice). All F1 plants from the two crosses had pubescent leaves, confirming that the pubescence trait in Chuanxiang 29B is dominant over the glabrous trait. In F2 individuals, the segregation ratio of three pubescent to one glabrous plant suggests that a single glabrous gene was present in Lemont and R2. Using the bulked segregant analysis, the linkage analysis of the simple sequence repeat markers showed that the glabrous gene, gl-1, was flanked by GL311 and GL8 with the genetic distances of 0.19 and 0.92 cM on chromosome 5, respectively.     

Haplotyping of Rice Genotypes Using Simple Sequence Repeat Markers Associated with Salt Tolerance

Salt stress is a major problem in most of the rice growing areas in the world. A major QTL Saltol associated with salt tolerance at the seedling stage has been mapped on chromosome 1 in rice. This study aimed to characterize the haplotype diversity at Saltol and additional QTLs associated with salt tolerance. Salt tolerance at the seedling stage was assessed in 54 rice genotypes in the scale of 1 to 9 score at EC = 10 d Sm-1 under controlled environmental conditions. Seven new breeding lines including three KMR3/O. rufipogon introgression lines showed similar salt tolerant ability as FL478 and can be good sources of new genes/alleles for salt tolerance. Simple sequence repeat(SSR) marker RM289 showed only two alleles and RM8094 showed seven alleles. Polymorphic information content value varied from 0.55 for RM289 to 0.99 for RM8094 and RM493. Based on 14 SSR markers, the 54 lines were clearly separated into two major clusters. Fourteen haplotypes were identified based on Saltol linked markers with FL478 as the reference. Alleles of RM8094 and RM3412 can discriminate between the salt tolerant and susceptible genotypes clearly and hence can be useful in marker-assisted selection at the seedling stage. Other markers RM10720 on chromosome 1 and RM149 and RM264 on chromosome 8 can also distinguish tolerant and susceptible lines but with lesser stringency.     

Evaluation of Population Structure,Genetic Diversity and Origin of Northeast Asia Weedy Rice Based on Simple Sequence Repeat Markers

Weedy rice exerts a severe impact on rice production by competing for sunlight, water and nutrients. This study assayed the population structure, genetic diversity and origin of Northeast Asia weedy rice by using 48 simple sequence repeat markers. The results showed that weedy rice in Northeast Asia had a high genetic diversity, with Shannon's diversity index(I) of 0.748 and the heterozygosity(He) of 0.434. In each regional population, I value varied widely. The widest range of I(0.228–0.489) was observed in the weedy rice of Eastern China, which was larger than that of Northeast China and Korea(0.168–0.270). The F-statistics of regional populations(Fis, Fit and Fst) also showed higher values in the weedy rice of Eastern China than those of Northeast China and Korea. All weedy rice accessions were grouped into two clusters in the unweighted pair group method with arithmetic mean cluster analysis dendrogram, namely Eastern China branch and Northeastern China plus Korea branch. There was significant differentiation in genetic characteristics in weedy rice of northeastern and eastern Asia, especially in Eastern China.     

Cluster Analysis on Japonica Rice （Oryza sativa L.） with Good Eating Quality Based on SSR Markers and Phenotypic Traits

Diversity of 60 conventional japonica rice accessions with good eating quality at home and abroad was analyzed using SSR molecular markers,agronomic traits and taste characteristics.A total of 290 alleles were detected in the 60 accessions at 72 SSR loci with the high similarity coefficients varying between 0.600 and 0.924.The loci on chromosome 5 showed the greatest value in average allele number.Additionally,most of the SSR loci could detect 3 to 4 alleles.An UPGMA dendrogram based on the cluster analysis...     

Genetic Diversity among Parents of Hybrid Rice Based on Cluster Analysis of Morphological Traits and Simple Sequence Repeat Markers

Heterosis has been successfully exploited on a large scale in rice (Oryza sativa L.), which is a self-pollinated crop. The selection of parental lines plays a vital role in developing ideal combinations. Therefore, it is essential to study the relationshi…     

籼稻RAPD标记遗传距离与杂种后代稻米味度及RVA谱特性的相关分析

 选用8个籼稻品种按Griffing双列杂交方法Ⅳ配制28个F1杂交组合，分析了RAPD分子标记籼稻遗传距离与稻米味度及淀粉粘滞性谱（RVA谱）杂种优势的关系。结果表明， 利用297个多态性RAPD标记位点计算8个亲本间分子标记遗传距离，其范围在0.197~0.349，平均为0.269，8个亲本可划分为2个类群；味度值和RVA谱的中亲优势平均而言介于双亲之间，分子标记遗传距离与F1味度值和RVA谱的表现以及杂种优势间的相关均不显著，味度值和RVA谱杂种优势与亲本间的遗传差异大小无关；双亲味度和RVA谱平均值与杂种味度和RVA谱之间均呈极显著的正相关，双亲味度值和RVA谱的平均值高，杂种味度值和RVA谱也就高。