水稻籼粳杂种生殖障碍的基因定位分析

籼稻(Oryza sativa L.ssp.indica)与粳稻(O.sativa ssp.japonica)杂交优势明显但存在生殖隔离。生殖障碍主要表现为胚囊败育、花粉败育、开花时花药不开裂和雌雄异熟。应用具有137个标记位点的籼、粳杂交(“窄叶青8号”/“京系17”)F_1花药培养获得的127个双单倍体(DH)群体构建的RFLP图谱,对控制籼、粳杂种小穗败育的基因座位进行了定位研究。结果在第1、3、4、5、6、7、8、12染色体上检测到10个基因座位,其中第3、12染色体上的2个不育基因位点stj-3和stj-12与同一杂交组合F_2分离群体中发现的异常分离热点处于相同的染色体区段。Ssj-6的基因加性效应为负值,有增加籼、粳亲和性的作用;其余的不育基因座位皆有增加籼、粳杂种不育性的作用。     

籼、粳杂种的“随体丢失”

1985—1986,观察籼、粳及籼,粳F_1杂种终变期核仁染色体数,籼为2个二价核仁染色体,粳为1个二价核仁染色体,籼、粳F_1杂种核仁染色体数与父本水稻的核仁染色体数相同。由此,讨论了“随体丢失”在水稻育种,粳稻起源及遗传学方面的意义。     

在水稻花培后代中RFLP零等位的遗传分析

在构建水稻分子图谱的研究中,有４ 个ＲＦＬＰ探针揭示了一对籼粳稻之间的零等位现象．其中ＲＧ ２２９ 揭示了籼稻“圭６３０”（Ｏｒｙｚａ ｓａｔｉｖａ ｓｓｐ． ｉｎｄｉｃａ）两个零等位位点;ＲＧ ４１９,ＲＧ４２４ 及ＲＧ ３５３ 揭示了粳稻“０２４２８”（Ｏ． ｓａｔｉｖａ ｓｓｐ．ｊａｐｏｎｉｃａ）的零等位． 利用８１ 个圭６３０／０２４２８ 的花培植株（ＤＨ）进行的遗传分析结果表明,这些零等位位点与ＭｃＣｏｕｃｈ 发表的水稻分子图谱中其相邻分子标记间的连锁关系发生了变化．另外,用ＲＧ ６８４ 探针在一些ＤＨ植株中检测出有新的零等位出现,虽然双亲都具有与ＲＧ ６８４ 同源的序列． 零等位的出现可能与转座因子的转位有关     

贵州地方水稻种质资源籼-粳遗传分化的InDel分子标记研究

本研究利用36对InDel分子标记引物对贵州地方水稻种质的籼-粳遗传分化和亲缘关系进行分析,结果表明,82份贵州地方栽培稻中49份为粳稻,33份为籼稻,贵州地方栽培稻“禾”品种主要属于粳稻,而“谷”品种主要为籼稻。基于Nei氏遗传距离的亲缘关系分析表明在粳稻群体和籼稻群体中均存在与野生稻亲缘关系近的品种,其中的粳稻品种与野生稻的遗传关系比之籼稻品种近。而基于MCMC算法的遗传结构分析揭示了贵州地方籼稻品种中存在较为复杂的遗传结构。分子变异分析显示,粳稻和籼稻品种的遗传变异主要来自亚种内,遗传多样性分析表明其亚种内籼稻品种的遗传多样性略高于粳稻品种。研究结果揭示了贵州省黔东南地区栽培稻种质资源的籼-粳分化程度、遗传关系及其遗传多样性。     

水稻感光性和光敏不育性的发育遗传关系

在人工气候室控制的光长与温度下,用光敏不育系7001S与早中熟粳稻(Oryza sativa ssp,japoni-ca)感光性弱的“秋光”、“有芒早粳”和“CPSLO-l7”3个品种分别杂交,分析了杂种F_1、F_2植株育性与感光性的表现,以及两者的关系。结果表明:这3个组合的恢复亲本均属于具两对光敏不育的恢复基因的品种。F_1植株均倾向晚熟亲本,说明控制感光性强的基因属于显性。F_2植株在长日照下表现为不育株的感光性均倾向感光性强的亲本;且有不少不育株为晚熟超亲;在少数弱感光性的植株中没有不育株。说明光敏不育基因与感光性基因关系密切,可能两者有连锁关系,光敏不育基因要在感光性基因表达的基础上才能表达。     

利用RFLP标记分析一对水稻籼粳交双单倍体的基因型

对一对籼(Oryza sativa ssp.indica)粳(O.sativa ssp.japonica)(“圭630”/“02428”)杂种进行花药培养获得81个双单倍体(DH),构建了有233个RFLP标记的水稻遗传连锁图谱。对各DH系的“圭630”等位基因组频率及图示基因型进行了分析。结果表明,该DH群体的平均基因组频率为49％,各DH系分布在29.3％～78.6％之间,集中分布在44％～49％之间;有130个RFLP标记出现显著的偏分离,偏父本与偏母本分离的标记数基本相等;同向偏分离的标记常集中在一些染色体或染色体的某些区段;各染色体的平均基因组频率分布在29％～65％之间,出现明显的偏父或偏母分离;一些DH中出现其特征完全来于某一亲本的染色体,可能与这些染色体在减数分裂期的同源配对和交换有关。     

水稻寡分蘖突变体的遗传分析和基因定位

从籼粳交组合“圭630/02428”的花培后代中获得一份寡分蘖突变体G069,其主要特征是分蘖速度慢,最高分蘖数少,成熟叶片叶尖、叶缘黄化.用突变体作母本与02428杂交,并以02428作轮回亲本与杂交后代突变型单株回交构建BC₂F₂.对BC₂F₂进行调查和遗传分析,确认突变体G069寡分蘖特性和叶片黄化现象受同一隐性基因控制.以BC₂F₂分离群体为基础,应用SSR标记和RFLP标记进行连锁分析,将寡分蘖基因定位于第2染色体的RFLP标记C424和S13984之间,分别相距2.4和0.6cM.该基因暂定名为ft1.     

花生黄曲霉侵染抗性的SCAR标记

利用与花生黄曲霉侵染抗性基因紧密连锁的AFLP标记 “E45/M53-440”, 经PAGE凝胶电泳后回收、克隆、测序, 并根据测序结果设计PCR特异引物, 通过对PCR条件的优化, 成功地将AFLP标记“E45/M53-440”转化为实验结果稳定, 操作更简单的SCAR标记“AFs-412”, 标记与花生黄曲霉侵染抗性间的遗传距离为6.5 cM。利用获得的SCAR标记对抗、感黄曲霉的花生种质资源进行了分子鉴定, 结果表明标记与抗性鉴定结果具有较高的一致性, 证实了该标记应用于研究群体之外的育种潜力。SCAR标记的建立为开展花生黄曲霉侵染抗性的标记辅助选择育种提供了简便实用的鉴定技术。     

利用分子标记和水稻籼粳交双单倍体群体进行遗传作图研究

利用“圭 630”(籼稻 ,Oryza sativa subsp.indica) /“0 2 4 2 8”(粳型广亲和品种 ,O.sativa subsp.japonica)的 F1代花药培养双单倍体植株 ( DH)群体和 RFLP标记构建了一张水稻分子连锁图谱。图上有 2 33个标记 ,覆盖基因组约 2 0 70 c M( centimorgan) ,定位了 2 5个 RFLP新标记、2个染色体端粒和水稻落粒性基因 sh- 2。亲本间的 RFLP主要来源于碱基取代 ,少数来源于 DNA结构的变化。RFLP标记在图谱上的排序与其它图谱基本相同 ,但标记在染色体间和染色体内分配不均 ,这可能与染色体间的遗传稳定性和染色体内的区段变异性 ,以及各区段交换重组活性不同有关。     

水稻抗白叶枯病基因Xa-4的PCR标记研究

根据与水稻抗白叶枯病基因Xa-4紧密连锁的分子标记M55的序列设计引物,通过对国际水稻研究所育成的抗白叶枯病近等基因系和基因累加系的叶片DNA、半粒种子提取物及Xa-4基因的杂合体DNA的PCR特异扩增,初步建立了Xa-4的PCR标记体系。进而用该标记体系对我国籼型杂交水稻常用的亲本材料进行分析,揭示出了Xa-4在这些材料中的分布情况。 Abstract　Based on the sequence of a DNA marker tightly linked to the rice bacterial blight（BB） resistance gene Xa-4, two primers were designated and synthesized to develop a PCR marker for the gene. Specific amplified polymorphism analysis was carried out with these primers on a set of BB resistance isogenic lines and pyramided lines developed by IRRI. Two PCR bands were revealed corresponding to lines with dominant Xa-4 and those with the recessive allele, respectively, regardless the lines pyramided with other resistance genes. A hybrid with heterozygous Xa-4 produced both of the two allele PCR pattern. Then, the PCR marker was used to survey a range of hybrid rice germplasm. The results of the germplasm survey will be useful in hybrid rice breeding programs aimed at exploiting Xa-4.     

Genetic Analysis of Null Alleles in Rice Doubled Haploid Plants from Anther Culture

In the research of constructing a rice(Oryza sativa) molecular map, 4 RFLP markers, i.e. RG 229, RG 419, RG 424 and RG 353, detected the null alleles in the indica and japonica parental rice. RG 229 indicated two null alleles in indica rice Gui 630, and each of the other markers revealed a null allele in japonica rice 02428. Genetic analysis in the doubled haploid (DH) population consisting of 81 plants showed that the linkage relationships between these null allele loci and the neighboring molecular markers shown in McCouch' s rice molecular map were changed. In addition, the marker RG 684 could detect its null alleles in some DH plants, though the RG 684 sequence did exist in the genomes of both parents. Appearence of null alleles might be induced by transpositional changes on chromosomes.     

Distorted Segregations of RFLP Markers and Their Distribution on Chromosomes in an indica/japonica F2 Population of Rice (Oryza sativa L.)

he segregation ratio of RFLP markers in an F2 population from indica "Zhaiyeqing 8” and japonica "Jingxi 17' of rice (Oryza sativa L., 2n= 24) was studied using 54 RFLP markers distributed on 12 chromosomes. Distorted segregation was found in 25.9% of the marker tested, which was indicated by significant deviation from the expected Mendelian segregation ratio ( I: 2: 1) at 5% or 1% level. Among the three RFLP genotypes of the F2 population “Zhaiyeqing” 8 genotype was significantly more than the expected, and its gene frequency was up to 52.1 %. Three positions for distorted segregation were found on chromosome 3 (RG227-RG369), 7 (RG678-RG511-RG528) and 12 (RG463-RG323). These positions could be related to gametophyte loci responsible for the distortion.     

Molecular Biological Identification of a Rice Salt Tolerant Line

A rice salt tolerant line No.170 was obtained from EMS treated anther culture of japonica variety and selected under salinity stress. The salt tolerance trait has been stably inherited through nine generations. In order to characterize this mutant line in molecular biological respects, 130 RFLP genetic markers along 12 pairs of chromosomes based on McCouch’s. rice RFLP linkage map were used to assay polymorphism between the mutant line and its original variety, was shown that allelic differences were found at two linked loci RG711 and RG4 on chromosome 7. Besides, proteins of roots and leaves between the mutant and the control plants were compared by means of two dimensional polyacrylamide gel electrophoresis. The comparison showed that some new proteins appeared in the salt tolerant plant under salinity-stress condition, which might be produced by salt inducible genes.     

Non-allelic interaction conditioning spikelet sterility in an F2 population of indica/japonica cross in rice

Significant segregation of spikelet fertility occurred in an F₂ population derived from a spikelet fertility-normal F₁ hybrid produced by a cross between Palawan, a japonica variety, and IR42, an indica variety. To identify factors controlling the fertility segregation, we used 104 RFLP markers covering all 12 rice chromosomes to investigate the association of spikelet fertility and marker segregation. We found that the segregation of two sets of gene pairs was significantly (P < 0.001) associated with fertility segregation. The first pair of genes was linked to RFLP marker RG778 on chromosome 12 and RFLP markers RG690/RG369 on chromosome 1. A significant reduction in fertility was observed when the plants were homozygote at RG778 with the indica allele as well as homozygote at RG690/RG369 with the japonica allele. The second pair of genes was linked to RG218 on chromosome 12 and RG650 on chromosome 7, respectively. The recombinant homozygote at these two loci showed a significant reduction on spikelet fertility. The non-allelic interaction effect was further modified by a gene linked to RG778, resulting in even lower fertility. The results of this study provides the first evidence of chromosomal localization of sporophytic sterility genes whose interaction can result in a reduction of spikelet fertility in the F₂ derived from fertility-normal F₁.     

应用微卫星标记鉴别水稻籼粳亚种

应用70个微卫星标记分析了3个籼稻测验种和3个粳稻测验种的多态性,发现其中36个标记可以区分籼粳测验种。再以18个籼粳品种进一步筛选,找到了分布于12条染色体的21个籼粳特异性微卫星标记。在这21个标记中,20个在籼粳亚种间带型相异,其中7个在亚种内带型一致,13个在亚种内带型不一致;1个标记在12个籼稻品种和1个粳稻品种检测到相同的带型,其余11个粳稻品种具有另一种带型。微卫星标记和RFLP标记检测籼粳亚种不仅具有一致性,而且还有互补性。 Abstract:Six indica and japonica testers were assayed using 70 microsatellite markers.Thirty-six markers distinguishing indicas from japonicas were detected.By further-screening among 18 indica and japonica varieties,21 markers distributed on 12 rice chromosomes were found to be indica-japonica differentiated.No indica varieties shared same patterns with any japonica varieties at 20 marker loci,of which identical patterns were observed within subspecies at 7 loci while within-subspecies variations were observed at 13 loci.At the remaining locus,12 indica and 1 japonica varieties had the same allele,while other 11 japonica varieties had another allele.It also showed that SSLP was not only consistent,but also complementary,to RFLP for the subspecies identification.     

秋稻品种Dular广亲和基因的RFLP分析

利用Ｂａｌｉｌｌａ／Ｄｕｌａｒ／ＩＲ３６和南京１１／／Ｄｕｌｕｒ／２５３３两个三交Ｆ１ 本对秋稻品种Ｄｕｌａｒ的广亲和性进行了遗传分析。为使杂种群体在相对一致的条伯下抽穗,所有三交Ｆ１植株于分化前集中进行了为期１周的短日照处理。结果表明,两个群体的小穗育性于多峰连续分布,说明三交群体的育性可能受几个主基因控制并受到微效基因的修饰,进一步采用分群分析法,以南京１１／／Ｄｕｌａｒ／２５３３为分析群体进     

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。     

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.     

一个新的水稻叶绿素缺失黄叶突变体的特征及基因分子定位

从粳稻"嘉花1号"60Coγ射线辐照的后代中筛选到一个叶绿素缺失黄叶突变体(yl11),与野生型"嘉花1号"相比该突变体表现为全生育期植株叶片呈黄色,叶绿素含量以及净光合速率明显下降,叶绿体发育不完善,并且伴随着株高等主要农艺性状的变化。遗传分析表明,该突变性状受一对隐性核基因(yl11)控制。该突变体与籼稻"培矮64S"杂交生产的F2、F3群体中的分离出突变体型920个单株作为定位群体,利用SSR和InDel分子标记将yl11基因定位在水稻第11染色体长臂上的MM2199和ID21039分子标记之间,其物理距离约为110kb,目前该区域内没有发现与水稻叶绿素合成/叶绿体发育相关已知功能基因。研究结果为今后对该基因的克隆和功能分析奠定了基础。