水稻卷叶半不育突变体的鉴定及初步遗传分析

利用EMS诱变获得一个武运粳21背景下稳定的卷叶半不育突变体rlms1。与野生型相比,突变体结实率极显著降低,只有40.6%,呈现半不育;株高极显著降低,籽粒宽度显著变窄,叶片卷曲度极显著增大;在叶片卷曲处,突变体的泡状细胞数量减少、体积减小,叶肉细胞排列紊乱,且厚壁细胞数量更多,导致叶片向内卷曲;突变体花粉可染率仅为70.4%,低于野生型的96.7%;遗传分析表明,卷叶半不育突变性状受1对隐性核基因控制。研究结果为该突变体的基因克隆和功能分析奠定了基础,为水稻株型改良提供了新的资源。     

一个水稻双子房突变体的表型鉴定和遗传分析

在籼稻保持系C2与绵香5B的杂交后代中发现了一个植株显著矮化的双子房突变体。该突变体花器官主要表现为：雄蕊数目减少,雌蕊增加,双子房,多柱头,胚囊畸形,有雄蕊雌蕊化现象。由于其高度不育,突变性状采用杂合体保存,经5代连续自交,均表现稳定遗传特性。同时,杂合株系呈典型的3∶1分离比例,表明该突变性状由单隐性基因控制,并将该突变体暂时命名为TOR。     

水稻迟抽穗突变体dth9的遗传分析与基因定位

在EMS诱变的93-11突变体库中筛选到一个稳定遗传的迟抽穗突变体dth9(days to heading 9)。该突变体的抽穗期比野生型延长了50d左右,其他农艺性状基本无异。遗传分析表明迟抽穗性状受一个隐性核基因控制。以突变体dth9与日本晴和武运粳7号杂交构建的F2分离群体作为定位群体,利用SSR标记和新开发的8个InDel标记,将DTH9定位在第9染色体着丝粒附近D9-9和D9-17之间240kb的区间内,该区域尚未发现与抽穗期有关的基因。此外,实时荧光定量PCR结果表明,在突变体dth9中与抽穗期相关基因的表达量显著降低。     

水稻雄蕊雌蕊化突变体的遗传分析

在杂交育种后代中发现了一个水稻雄蕊雌蕊化突变体 ,表现为 :外颖和内颖变窄 ,外颖弯曲呈弯月形 ,内外颖不闭合 ,1～5枚雄蕊转变为雌蕊或雌蕊 雄蕊嵌合体。由于高度雌性不育 ,突变纯合体本身无繁殖保持功能 ,只能通过杂合体繁衍 ,在自交 15代后仍分离出完全相同的突变体 ,表现稳定遗传特性。遗传分析表明该突变体由单隐性基因控制。     

水稻雄性不育突变体TP79的遗传分析及细胞学研究

TP79是一个源于水稻品种台北309的自然突变的不育突变体,对该突变体进行遗传分析和细胞学研究,结果显示,TP79小花雌蕊正常,雄蕊6枚,花丝细长,花药干瘪,花粉以染败类型为主;利用TP79与台北309杂交进行遗传分析,结果表明,TP79是单隐形核基因控制的雄性不育突变体;组织切片观察发现,TP79在小孢子形成前期出现异常,绒毡层不能正常降解,小孢子的发育畸形,在最终花粉成熟期,绒毡层仍呈浓缩状,形成的花粉干瘪,无活性。     

水稻短根毛突变体ksrh1的遗传分析和基因定位

从EMS诱变的籼稻品种Kasalath突变体库中筛选获得了一个短根毛突变体,命名为ksrh1。该突变体在苗期表现为根毛变短,除此之外其表型与野生型没有显著差异。遗传分析表明,该突变性状受1个隐性单基因控制。将突变体ksrh1与粳稻品种日本晴杂交构建F2定位群体,利用已公布的水稻SSR标记和自行设计的STS标记对突变位点进行基因定位,最终将KSRH1定位在水稻第1染色体长臂上的S3578和S3584之间,物理距离约为67kb。     

水稻多分蘖矮秆突变体d63的遗传分析与基因定位

 多分蘖矮秆突变体d63来源于SARⅢ二倍体与明恢63杂交得到的双胚苗株系的自然突变。与野生型相比,其株高显著下降,分蘖明显增多,剑叶变细变短,结实率和千粒重均大幅下降。遗传分析表明,该突变性状受一对隐性单基因控制。该基因位于水稻第8染色体短臂上距离RM22195约0.4 cM的位置。用水稻基因组注释软件Rice Genome Annotation预测,发现从端粒区至RM22195间共有14 个注释基因,未发现已经报道的与株高、分蘖相关的同源基因。因此,推测D63可能是一个未被报道的新基因。     

一个水稻颖壳扭曲突变体的遗传分析与基因定位

 从水稻育种后代材料中获得1个颖壳扭曲突变体Osth (twisted hull)。遗传分析结果表明,该突变性状由单核基因隐性突变造成。以突变体与颖壳正常籼稻R725杂交的F2群体为基因定位群体,利用SSR标记将突变位点定位在第2染色体上的SSR标记RM14128与RM208之间,遗传距离分别为1.4 cM 和2.7 cM。这些结果为该基因的精细定位和克隆以及研究水稻花发育的分子机理奠定了基础。     

水稻突变体的创制与遗传分析

本文综述了水稻突变体的创制与遗传分析、基因定位的研究进展,包括1698个水稻突变体／基因的分类和已公布的30个图位克隆的水稻基因。并提出了利用水稻突变体的展望。     

Characterization and Genetic Analysis of Rumpled and Twisted Leaf Mutant(rtl1) in Rice

A rumpled and twisted leaf 1(rtl1) mutant was generated from a japonica cultivar Nipponbare by ethyl methanesulfonate treatment,which was characterized as rumpled and twisted leaf at the seedling stage.The F2 populations were constructed by crossing with indica cultivars TN1 and Zhefu 802,respectively.Genetic analysis demonstrated that the phenotype was controlled by a single recessive nuclear gene.The closely linked simple sequence repeat(SSR) marker RM1155 was obtained from bulked segregant analysis.Subse...     

Genetic Analysis and Mapping of TWH Gene in Rice Twisted Hull Mutant

A mutant with twisted hulls was found in a breeding population of rice (Oryza sativa L.). The mutant shows less grain weight and inferior grain quality in addition to twisted hulls. Genetic analysis indicated that the phenotype of mutant was controlled by a single recessive gene (temporarily designated as TWH). To map the TWH gene, an F2 population was generated by crossing the twh mutant to R725, an indica rice variety with normal hulls. For bulked segregant analysis, the bulk of mutant plants was prepared by mixing equal amount of plant tissue from 10 twisted-hull plants and the bulk of normal plants was obtained by pooling equal amount tissue of 10 normal-hull plants. Two hundred and seven pairs of simple sequence repeat (SSR) primers, which are distributed on 12 rice chromosomes, were used for polymorphism analysis of the parents and the two bulks. The TWH locus was initially mapped close to the SSR marker RM526 on chromosome 2. Therefore, further mapping was performed using 50 pairs of SSR primers around the marker RM526. The TWH was delimited between the SSR markers RM14128 and RM208 on the long arm of chromosome 2 at the genetic distances of 1.4 cM and 2.7 cM, respectively. These results provide the foundation for further fine mapping, cloning and functional analysis of the TWH gene.     

一个水稻类树稻突变体(leafy head 3)基因的精细定位

 从常规粳稻常优94后代中筛选到一份自然突变的抽穗期延迟的类树稻突变体lhd3（leafy head 3）。在短日照条件下,与野生型比较,lhd3突变体在生长后期,上部节间会继续长出叶片（一般为3片）和高位分蘖,类似于树的侧枝生长,抽穗期延迟,但基部分蘖数不受影响。经典遗传分析表明,lhd3与籼稻南京6号的F2群体中,正常植株与类树稻植株的分离比符合3∶1,说明此性状受单隐性基因控制。利用该群体进行图位克隆,将LHD3基因定位在水稻第1染色体短臂的两个新发展的STS标记wpla3和wpla25之间。再利用5个新发展的STS和CAPS标记,最终将该基因精细定位在WX6和CAPS1两个标记之间,物理距离约为60 kb。通过水稻基因组注释系统共预测到10个开放阅读框（ORF）。对该基因的进一步克隆将有助于阐明水稻生育期和叶原基发育调控机理。     

一个水稻分蘖角度突变体tac2的遗传分析和基因初步定位

  水稻散生突变体tac2是以恢复系缙恢10号为材料经甲基磺酸乙酯（EMS）化学诱变所得。该突变体苗期表型正常,分蘖期株型松散,分蘖角度较野生型显著增大,株高明显降低。外源赤霉素处理可以使该突变体株高恢复,但分蘖角度不受影响。遗传分析表明该突变性状受1对隐性主效基因控制。利用分子标记将该基因初步定位于第9染色体上的RM3320与RM201之间,遗传距离分别为19.2和16.7 cM。     

Genetic Analysis and Gene Mapping of Multi-tiller and Dwarf Mutant d63 in Rice

A spontaneous mutation,tentatively named d63,was derived from the twin-seedling progenies of rice crossed by diploid SARIII and Minghui 63.Compared with wild-type plants,the d63 mutant showed multiple abnormal phenotypes,such as dwarfism,more tillers,smaller flag leaf and reduced seed-setting rate and 1000-grain weight.In this study,two F 2 populations were developed by crossing between d63 and Nipponbare,d63 and 93-11.Genetic analysis indicated that d63 was controlled by a single recessive gene,which was located on the short arm of chromosome 8,within the genetic distance of 0.40 cM from RM22195.Hence,D63 might be a new gene as there are no dwarf genes reported on the short arm of chromosome 8.     

Genetic Analysis and Gene Mapping of a Rice Tiller Angle Mutant tac2

Tiller angle, a very essential agronomic trait, is significant in rice breeding, especially in plant type breeding. A tiller angle controlling 2 (tac2) mutant was obtained from a restorer line Jinhui 10 by ethyl methane sulphonate mutagenesis. The tac2 mutant displayed normal phenotype at the seedling stage and the tiller angle significantly increased at the tillering stage. A preliminary physiological research indicated that the mutant was sensitive to GA. Thus, it is speculated that TAC2 and TAC1 might control the tiller angle in the same way. Genetic analysis showed that the mutant trait was controlled by a major recessive gene and was located on chromosome 9 using SSR markers. The genetic distances between TAC2 and its nearest markers RM3320 and RM201 were 19.2 cM and 16.7 cM, respectively.