光敏核不育水稻农垦58S与正常品种“农垦58”在pms1区段无育性基因…

光敏核不育水稻农垦５８Ｓ系由正常品种“农垦５８”自然突变产生。为弄清该突变基因在染色体上的位置,曾用覆盖整个水稻基因组的３００余个ＲＦＬＰ探针对农垦５８Ｓ和“农垦５８”进行了对比分析,得到了７个具多态性的探针,其中２个探针ＲＧ３０和ＺＲ６２６正好落在第７染色体上以前定位的光敏核不育基因ｐｍｓ１所在的区段。以这两个标记对农垦５８Ｓ／“农垦５８”组合Ｆ２随机群体１４０单株进行了ＲＦＬＰ分析,按ＲＦＬＰ     

水稻的AFLP研究初报——反应条件的优化及对温敏核不育等位突变系的分析

通过对５４６０Ｓ和５４６０Ｆ这一对水稻等位突变系的ＡＦＬＰ分析,比较了ＡＦＬＰ与ＲＡＰＤ及ＲＦＬＰ检测ＤＮＡ多态性的相对效率。结果表明,这３种分子标记的ＤＮＡ多态性检出效率依次为ＡＦＬＰ＞ＲＡＰＤ＞ＲＦＬＰ;找出了水稻ＡＦＬＰ分析的最适反应条件;在这对等位突变系之间找到了一些多态性ＡＦＬＰ产物,已完成了对４个多态性ＡＦＬＰ产物的克隆,其中３个为单拷贝顺序;用这３个单拷贝克隆的混合物为探针,对作者自己构建的５４６０Ｓ水稻的ＢＡＣ库进行了筛选,获得了１２个阳性克隆,为今后ＢＡＣ库的筛选打下了基础。此外,对上述３种分子标记各自的优缺点及它们在ＤＮＡ多态性检测中的适用之处进行了分析探讨。     

光敏核不育水稻光敏色素基因的RFLP分析

以灿稻“ＩＲ３６”光敏色素基因ｐｈｙＡ的ｃＤＮＡ克隆作探针,对光敏核不育水稻“农垦５８Ｓ”和对照水稻“农垦５８”进行ＲＦＬＰ分析,性内切酶ＥｃｏＲｖ,ＤｒａＩ,ＨｉｎｄⅢ、ＸｂａＩ、ＭｓｐＩ等都没有显示出多态性,而用ＨｐａⅡ显示出了多态性。ＭａｐＩ和ＨｐａⅡ是一对同裂酶（识别位点为ＣＣＧＧ）,但二者对识别位点上第２个胞嘧啶（即ＣｐＧ）甲基化的敏感性不同。实验结果表明,“农垦５８Ｓ”ｐｈｙＡ基因中Ｃ     

应用分子标记研究氮素胁迫条件下水稻叶片叶绿素含量差异的遗传背景

在氮素限制供应条件下,灿稻品种ＩＲ４２与广亲合粳稻品种Ｐａｌａｗａｎ剑叶及下位叶的平均叶绿素含量差异显著,叶绿素含量在Ｐａｌａｗａｎ／ＩＲ４２杂交Ｆ２代中呈正态分布,１０４个分布与１２条染色体的ＲＦＬＰ标记基因型之间表型平均值方差分析与区间作图分析结果表明,分别位于染色体２,４,７上的３个ＱＴＬ位于ＲＺ５８／ＲＧ１０２,ＲＧ１４３／ＲＧ３２９和ＲＧ６３４／ＲＧ６５０之间。与ＲＧ１４３及ＲＧ１０２连     

利用分子标记定位农垦58S的光敏核不育基因

对农垦５８Ｓ（Ｏｒｙｚａｓａｔｉｖａｓｐ．ｊａｐｏｎｉｃａ）／大黑矮生标记基因系ＦＬ２组合组建可育集团和不育集团,并以亲本为对照进行了ＲＦＬＰ、ＲＡＰＤ和双引物ＲＡＰＤ分析,结果第１２染色体上的一个单拷贝标记Ｇ２１４０与光敏核不育基因连锁遗传,二者间的遗传图距为１４．１ｃＭ（ｃｅｎｔｉｍｏｒｇａｎ）。在筛选过的１０４０个随机单引物和１９０个双引物中,仅引物ＯＰＡＵ１０扩增出与光敏核不育基因连锁的１．５ｋｂＤＮＡ片段,回收、克隆该ＤＮＡ片段并制备探针,将其转换成共显性的ＲＦＬＰ标记并命名为ＯＰＡＵ１０１５００。分离群体连锁分析表明该标记与标记Ｇ２１４０紧密连锁,将农垦５８Ｓ的一对光敏核不育基因定位于第１２染色体上。     

利用RFLP、SSR、AFLP和RAPD标记分析玉米自交系遗传多样性的比较研究

利用 ＲＦＬＰ、ＳＳＲ．ＡＦＬＰ和ＲＡＰＤ ４种分子标记方法研究了 １５个玉米（Ｚｅａ ｍａｙｓ Ｌ．）自交系的遗传多样性,同时对４种标记系统进行比较。在供试材料中筛选到具多态性的ＲＦＬＰ探针酶组合５６个,６６对ＳＳＲ引物,２０个ＲＡＰＤ引物和９个ＡＦＬＰ引物组合,分别检测到多态性带１６７、２０１、８７和１０８条。ＳＳＲ标记位点的平均多态性信息量（ＰＩＣ）最大（０．５４）,ＡＦＬＰ标记位点最小（０．３６）,但ＡＦＬＰ标记具有最高的多态性检测效率（Ａｉ,３２．２）。４种分子标记所得遗传相似系数相关性显著,比较相关系数表明 ＲＡＰＤ可靠性较低。依据 ４种分子标记结果将 １５个供试自交系划分为塘四平头、旅大红骨、兰卡斯特、瑞德和ＰＮ共５个类群,与系谱分析基本一致。认为ＳＳＲ和ＲＦＬＰ两种分子标记方法适合进行玉米种质遗传多样性的研究。     

玉米CMS材料线粒体DNA遗传多型性的研究

选用１１×４＝４４个探针／酶组合,５０个（１０ｍｅｒ）随机序列引物对２５种不同胞质来源的ＣＭＳ玉米,５种正常胞质玉米线粒体ＤＮＡ进行ＲＦＬＰ和ＲＡＰＤ研究。研究结果表明：（１）４５％的探针／酶组合可检测到玉米线粒体ＤＮＡ的多型性,共表现１５种ＲＦＬＰ类型,其中Ｓ组ＣＭＳ材料内有７种,正常胞质材料内有２种;８０％的随机引物可检测到ＲＡＰＤ。（２）基于ＲＦＬＰ资料的聚类分析结果,可将３０种胞质明确地划分为Ｔ、Ｃ、Ｓ、Ｎ４组,其结果与恢复专效性测定结果一致。其中ｐＨＪ２－７－１／ＢａｍＨＩ的ＲＦＬＰ类型可成为利用ＲＦＬＰ技术进行胞质分组的鉴定体系。（３）“双”型胞质线粒体ＤＮＡ常表现Ｓ＋Ｃ胞质的ＲＦＬＰ图谱。     

利用RFLP,SSR,AFLP和RAPD标记分析玉米自效系遗传多样性的比较研究

利用ＲＦＬＰ、ＳＳＲ、ＡＦＬＰ和ＲＡＰＤ４种分子标记方法研究了１５个玉米（Ｚｅａ ｍａｙｓ Ｌ．）自交系的遗传多样性,同时对４种标记系统进行比较。在供试材料中筛选到具多态性的ＲＦＬＰ探针酶组合５６个,６７６对ＳＳＲ引物,２０个ＲＡＰＤ引物和９个ＡＦＬＰ引物组合,分别检测到多态性带１６７、２０１、８７和１０８条。ＳＳＲ标记位点的平均多态性检测效率（Ａｉ,３２．２）。４种分子标记所得遗传相似自交系划分     

九个水稻耐盐突变体的RFLP分析

用６ 个可能与水稻耐盐性有关的ＤＮＡ 探针对来自两个品系的５ 个耐盐突变株系、３ 个耐盐突变体及１ 个弱耐盐突变体进行ＲＦＬＰ分析。结果有８ 个耐盐突变体（株系）检测到ＤＮＡ 水平的变化,６ 个探针检测到具多态性的突变株系（体）的数目分别为ＲＧ４：６ 个;ＲＧ７１１：６ 个;Ｒａｂ１６：５ 个;Ｒａｂ１０Ｅ６：２ 个;Ｒａｂ２１：１ 个;ＳａｌＴ：２ 个;表明ＲＧ４、ＲＧ７１１ 及Ｒａｂ１６三个位点有可能与耐盐性突变相关。多态性图谱中７０．８％ 为２ 个以上的酶切图谱同时显示多态性,说明多数突变是由缺失、插入或重复造成的     

应用荧光原位杂交和RFLP标记检测多小穗小麦新种质10-A中的黑麦染色质

利用ＡＰＡＧＥ、荧光原位杂交技术和ＲＦＬＰ标记,对导入黑麦（ＳｅｃａｌｅｃｅｒｅａｌｅＬ．）多小穗等性状创制的小麦新种质１０＿Ａ进行了分子标记检测。ＡＰＡＧＥ分析发现,１０＿Ａ与其他１ＲＳ／１ＢＬ易位系一样,含有１ＲＳ的醇溶蛋白标记位点Ｇｌｄ１Ｂ３。以黑麦基因组总ＤＮＡ作探针,用中国春（Ｔｒｉｔｉｃｕｍａｅｓｔｉｖｕｍｃｖ．ＣｈｉｎｅｓｅＳｐｒｉｎｇ）基因组ＤＮＡ作封阻,与１０＿Ａ根尖细胞有丝分裂染色体进行荧光原位杂交。结果表明,黑麦的１ＲＳ易位到１０＿Ａ中。用２５个ＲＦＬＰ探针进行Ｓｏｕｔｈｅｒｎ分析,进一步发现１０＿Ａ的１ＢＳ特异限制性片段发生丢失,代之以黑麦１ＲＳ的特异限制性片段,而位于其他染色体上的特异限制性片段未发生缺失。据此认为,多小穗小麦新种质１０＿Ａ属于１ＲＳ／１ＢＬ易位系。同时还讨论了１０＿Ａ在小麦遗传改良中的利用情况。     

Primary Study of Rice AFLP Analysis-Optimization of Reaction Conditions and Analysis of Thermo sensitive Genic Male Sterile Rice Allelic Mutant Lines

AFLP analysis was performed between a pair of thermo-sensitive genic male sterile (TGMS) rice allelic mutant lines (5460S and 5460F). The reaction conditions for rice AFLP assay were optimized. The relative efficiencies for polymorphism detection of RFLP, RAPD and AFLP were compared. The results indicated that the efficiency for polymorphism detection in rice was in the order of AFLP > RAPD > RFLP, and also indicated that AFLP was a powerful DNA molecular marker technique for polymorphism detection, especially in the case of extremely low polymorphism, such as isogenic lines and allehc mutant hnes. Some of the AFLP products between the TGMS rice allehc mutant lines were cloned. Three of them were used as mixed probes to screen BAC library of rice line 5460S. 12 positive clones were screened out. In addition, the advantages and disadvantages of these three molecular marker systems were discussed.     

Segmental Duplications Are Common in Rice Genome

Segmental duplications on rice (Oryza sativa L.) chromosomes 8, 9, 11, and 12 were studied by examining the distributions of sequences resolved by 13 probes detecting multiple copies of DNA sequences. Four of the hybridization bands detected by a repetitive sequence probe, rTRS, were mapped to the ends of all the four chromosomes. Two or three of the bands detected by each of the other 12 probes were also mapped to different chromosomes. The bands detected by the same probe usually occurred in similar locations of different chromosomes. Loci detected by different DNA probes were often similarly arranged on different chromosomes. Chromosomes 8 and 9 showed colinearity of marker loci arrangement indicating a possible common origin. A segment on chromosome 9 was also very similar to the previously reported duplicated fragments on the ends of chromosomes 11 and 12 which were also detected in this study, indicating a likely common origin. Moreover, the various degrees of distributional similarity of the segments suggest a complex relationship among the chromosomes in the evolution of the rice genome. These results support the proposition that chromosome duplication and diversification may be a mechanism for the origin and evolution of the chromosomes in the rice genome.     

水稻基因组中的节段重复

利用１３个多拷贝探针,研究水稻（Ｏｒｙｚａ ｓａｔｉｖａ Ｌ．）基因组第８、９、１１和１２染色体上的节段重复。由同一探针检测到的多拷贝位点通常位于不同染色体的相同部位。不同探针检测到的多拷贝位点在不同染色体上的位置顺序相同。第８种９染色体上的相同多拷贝位点的线性排列,提示这两条染色体在进行上可能来源于同一原始染色体。而第９染色体上的一个节段与前人报道的以及本研究进一步证实的第１１和第１２染色体短臂     

Pms1 is not the Locus Relevant to Fertility Difference Between the Photoperiod-Sensitive Male Sterile Rice Nongken 58S and Normal Rice

The photoperiod-sensitive male sterile rice, Nongken 58S, was obtained as a spontaneous mutant of the Oryza sativa L. ssp. japonica cultivar "Nongken 58". To determine the chromosomal location of the locus related to the fertility difference between Nongken 58S and its wild-type ancestor, the authors assayed the DNA polymorphisms between these two varieties using a total of over 300 RFLP probes covering the entire molecular marker linkage map. Seven probes detected polymor- phisms between "Nongken 58" and Nongken 58S. Two probes, RG30 and RZ626, both from chromosome 7, happened to be located in the genomic region of pmsl, a locus for photoperiod-sensitive male sterility identified in the authors' previous study. These two probes were used to assay a random sample of 140 individuals from a F2 population of a cross between Nongken 58S and "Nongken 58", in which the fertility segregated in a typical 3: 1 ratio. An analysis of variance of the fertility using the RFLP genotypes as the groups clearly evidenced that these two marker loci are not linked to the locus associated fertility segregation in this population. It is concluded that the locus relevant to fertility difference between Nongken 58S and "Nongken 58" is not in the vicinity of the pmsl region.     

光敏核不育水稻农垦58S与正常品种“农垦58”在pmsl区段无育性基因分离

光敏核不育水稻农垦58S系由正常品种“农垦58”(Oryza sativa L.ssp.japonica)自然突变产生。为弄清该突变基因在染色体上的位置,曾用覆盖整个水稻基因组的300余个RFLP探针对农垦58S和“农垦58”进行了对比分析,得到了7个具多态性的探针,其中2个探针RG30和RZ626正好落在第7染色体上以前定位的光敏核不育基因pmsl所在的区段。以这两个标记对农垦58S/“农垦58”组合F_2随机群体140单株进行了RFLP分析,按RFLP基因型分组对育性作方差分析,结果表明,这2个标记位点与此群体中引起育性分离的位点无连锁关系。说明由正常“农垦58”变为光敏核不育农垦58S的突变基因不在pmsl区段。     

水稻花药培养植株后代的DNA变异

对籼稻圭６３０和粳稻０２４２８及其Ｆ１通过花药培养获得的８１个ＤＨ系进行了ＲＦＬＰ分析,有２８个探针揭示了ＤＮＡ变异。８１个ＤＨ系不同程度地发生了变异,并具有以下特点：（１）ＤＮＡ变异类型包括限制性片段长度的变化、９ＮＡ片段的丢失以及ＤＮＡ序列的扩增;（２）变异发生在籼稻圭６３０供体片段中的频率高于粳稻０２４２８,表现出基因型差异;（３）染色体组中第３、８、９和１０染色体较少发生变异,在其它染色体上均存在易变异位点;（４）在染色体的一些区段,相邻的探针均揭示了ＤＮＡ变异,表明在染色体上存在ＤＮＡ易变异区域;（５）变异位点和变异类型具有特异性,在同一位点不同的ＤＨ系中发生相同的变异。     

Variation in performance on cry1Ab-transformed and nontransgenic rice varieties among populations of Scirpophaga incertulas (Lepidoptera: Pyralidae) from Luzon Island, Philippines

We quantified variation in performance under greenhouse conditions among seven populations of Scirpophaga incertulas (Walker) from Luzon Island, Philippines, on three rice varieties: 'IR58' transformed with the cry1Ab gene from Bacillus thuringiensis Berliner, and nontransgenic IR58 and IR62. On IR62, S. incertutas performance did not differ among provinces for any of the 10 parameters measured, but there was a significant effect of town within province for one parameter, 20-d-old larval weight. Larval survival after 48 h on cy1Ab-transformed IR58 did not differ significantly among provinces, but did differ significantly among towns within a province. There was no geographic variation in larval survival after 48 h on control plants of IR58. Surviving insects from the cry1Ab-transformed IR58 were transferred to IR62 to complete development. There was no geographic variation in the percentage of insects completing development to adult emergence and the time required by the transferred female insects to complete development. However, there was variation among provinces in male developmental time. The absence of geographic variation on nontransgenic IR58 and the very limited variation on IR62 indicated that there was little variation in general vigor among the S. incertulas populations and thus that the variation in performance oil cry1Ab-transformed IR58 was probably attributable to differences in susceptibility to Cry1Ab.     

A new chromosome nomenclature system for oat (Avena sativa L. and A. byzantina C. Koch) based on FISH analysis of monosomic lines

Fluorescent in situ hybridization (FISH) with multiple probes was used to analyze mitotic and meiotic chromosome spreads of Avena sativa cv ‘Sun II’ monosomic lines, and of A. byzantina cv ‘Kanota’ monosomic lines from spontaneous haploids. The probes used were A. strigosa pAs120a (a repetitive sequence abundant in A-genome chromatin), A. murphyi pAm1 (a repetitive sequence abundant in C-genome chromatin), A. strigosa pITS (internal transcribed spacer of rDNA) and the wheat rDNA probes pTa71 (nucleolus organizer region or NOR) and pTa794 (5S). Simultaneous and sequential FISH employing pairs of these probes allowed the identification and genome assignation of all chromosomes. FISH mapping using mitotic and meiotic metaphases facilitated the genomic and chromosomal identification of the monosome in each line. Of the 17 ‘Sun II’ lines analyzed, 13 distinct monosomic lines were found, corresponding to four monosomes of the A-genome, five of the C-genome and four of the D-genome. In addition, 12 distinct monosomic lines were detected among the 20 ‘Kanota’ lines examined, corresponding to six monosomes of the A-genome, three of the C-genome and three of the D-genome. The results show that 19 chromosomes out of 21 of the complement are represented by monosomes between the two genetic backgrounds. The identity of the remaining chromosomes can be deduced either from one intergenomic translocation detected on both ‘Sun II’ and ‘Kanota’ lines, or from the single reciprocal, intergenomic translocation detected among the ‘Sun II’ lines. These results permit a new system to be proposed for numbering the 21 chromosome pairs of the hexaploid oat complement. Accordingly, the A-genome contains chromosomes 8A, 11A, 13A, 15A, 16A, 17A and 19A; the C-genome contains chromosomes 1C, 2C, 3C, 4C, 5C, 6C and 7C; and the D-genome consists of chromosomes 9D, 10D, 12D, 14D, 18D, 20D and 21D. Moreover, the FISH patterns of 16 chromosomes in ‘Sun II’ and 15 in ‘Kanota’ suggest that these chromosomes could be involved in intergenomic translocations. By comparing the identities of individually translocated chromosomes in the two hexaploid species with those of other hexaploids, we detected different types of intergenomic translocations.     

Genomic changes in resynthesized Brassica napus and their effect on gene expression and phenotype

Many previous studies have provided evidence for genome changes in polyploids, but there are little data on the overall population dynamics of genome change and whether it causes phenotypic variability. We analyzed genetic, epigenetic, gene expression, and phenotypic changes in approximately 50 resynthesized Brassica napus lines independently derived by hybridizing double haploids of Brassica oleracea and Brassica rapa. A previous analysis of the first generation (S0) found that genetic changes were rare, and cytosine methylation changes were frequent. Our analysis of a later generation found that most S0 methylation changes remained fixed in their S5 progeny, although there were some reversions and new methylation changes. Genetic changes were much more frequent in the S5 generation, occurring in every line with lines normally distributed for number of changes. Genetic changes were detected on 36 of the 38 chromosomes of the S5 allopolyploids and were not random across the genome. DNA fragment losses within lines often occurred at linked marker loci, and most fragment losses co-occurred with intensification of signal from homoeologous markers, indicating that the changes were due to homoeologous nonreciprocal transpositions (HNRTs). HNRTs between chromosomes A1 and C1 initiated in early generations, occurred in successive generations, and segregated, consistent with a recombination mechanism. HNRTs and deletions were correlated with qualitative changes in the expression of specific homoeologous genes and anonymous cDNA amplified fragment length polymorphisms and with phenotypic variation among S5 polyploids. Our data indicate that exchanges among homoeologous chromosomes are a major mechanism creating novel allele combinations and phenotypic variation in newly formed B. napus polyploids.