江淮流域杂草稻叶绿体DNA的籼粳分化

 为了探明江淮流域杂草稻的细胞质来源,根据水稻叶绿体DNA ORF100（Open Reading Frame 100）序列在籼粳间存在69 bp差异的特征,设计了InDel标记cpDNA69。利用该标记对2个分别以籼稻和粳稻为母本的F2群体、22份栽培稻（Oryza sativa L.）、3份普通野生稻（O. rufipogon Griff.）进行了分析验证。PCR结果可以获得缺失和非缺失两种带型,缺失带型与以籼稻为母本的F2群体、10份籼稻材料完全对应;非缺失带型与以粳稻为母本的F2群体、11份粳稻材料完全对应,3份广西普通野生稻为非缺失带型,属粳型,1份以粳稻为母本的籼粳杂交材料为粳型。因此,cpDNA69可以用作叶绿体籼粳鉴定标记。利用该标记对22份杂草稻的叶绿体DNA鉴定的结果表明,7份早年发现的杂草稻,即江苏省连云港穭稻和安徽省怀远、来安、全椒、肥东的塘稻的叶绿体DNA为非缺失带型,属粳型,而近年来在江苏省扬中、高邮、灌云、洪泽、盐都、兴化、如皋等地直播稻田发现的15份红米杂草稻的叶绿体DNA为缺失带型,属籼型。这为进一步研究江淮流域杂草稻的来源提供了依据。     

应用RFLP标记研究亚洲栽培稻的起源与分化

 选用分布于10条水稻染色体的20个DNA探针，分析了来源于广东、广西、福建、湖南和江西等5省的14份亚洲普通野生稻材料以及来源于8个国家的19份亚洲栽培稻材料的RFLP。17个探针能在研究材料间检测到多态性，以一种酶为基础，共检测到67条多态性带。聚类分析结果表明，所有野生稻材料归入野生稻组，栽培稻材料分别归入籼稻组或粳稻组。三组区分明确，且三组之间的遗传距离差别很小，表明灿粳稻是几乎同时从古老野生稻种分化而来的。另外，所有普通野生稻材料在籼粳分化方向基本都属于中间类型，且变异幅度不大于籼粳稻组内各材料在籼粳方向的变异幅度。     

栽培稻和普通野生稻基因组的随机扩增多态性DNA（RAPD）初步分析

 用35个随机引物对5个籼稻品种、5个粳稻品种和27份中国普通野生稻进行了RAPD分析。60%以上的引物能在籼稻和粳稻基因组间显示差异；中国普通野生稻与栽培稻的差异主要表现在与籼稻的不同，绝大部分供试野生稻的RAPD带型与粳稻的相同。这说明多数中国普通野生稻偏粳，但也存在偏籼的普通野生稻。     

栽培稻和普通野生稻基因组的随机扩增多态性DNA（RAPD）初步分析

用35个随机引物对5个籼稻品种、5个粳稻品种和27份中国普通野生稻进行了RAPD分析。60%以上的引物能在籼稻和粳稻基因组间显示差异;中国普通野生稻与栽培稻的差异主要表现在与籼稻的不同,绝大部分供试野生稻的RAPD带型与粳稻的相同。这说明多数中国普通野生稻偏粳,但也存在偏籼的普通野生稻。     

云南元江普通野生稻(Oryza rufipogon）群体籼粳分化的SSR分析

 利用经测验可区分籼粳品种的19对SSR特异引物对来自云南元江普通野生稻自然居群的56个个体进行了SSR分析。19对引物中，有17对（占89.47%）在所有参试个体中仅能扩增出一种带型，而RM18和RM251能扩增出多态带型。RM4等16对（84.21%）引物扩增出的带与籼稻或粳稻特征带相同，其中11个位点偏粳而4个位点偏籼；RM18、RM202、RM205等3对引物扩增出的带型不同于籼稻或粳稻带型。结果表明，云南元江普通野生稻基因组DNA在所检测的19个位点上，多数位点（89.47%）上个体间无差异，84.21%的位点已有籼粳分化，13.79%的位点仍具有原始性。说明云南元江普通野生稻主体比较纯而原始，但已开始了籼粳的分化。     

中国普通野生生稻的原始型及其是否存在籼粳分化的初探

 选用国内7省（自治区）571份，国外27份普通野生稻编号根据10个形态状进行了聚类分析并结合同工酶分析与野生稻原产地生态考察将中国普通野生稻划分为多年生和一年生两群共7个类型。提出中国存在一年生普通野生稻及原始型普通野生稻问题，并根据同工酶4个基困位点分析对另中国普却生稻是否存在籼粳分化问题进行了讨论。     

湖南澧县八十()遗址古栽培稻的再研究

用多种方法对 1 997年湖南澧县八十遗址出土的 782粒 80 0 0年前的古栽培稻谷的粒形等性状分析研究 ,观察到该古栽培稻是一个具有广泛性状变异性的不同于现代籼、粳、普通野生稻的近野生稻偏籼型的独立复合群体 ,且在演化地位上具有原始性和过渡性的特征。初步认定其为一个完全无人工选择条件下长期演化而成的原始栽培稻类型     

北方野生稻资源研究初报

1　概况我国的栽培稻分为籼、粳两大亚种 ,北方稻区栽培的是粳型品种。由于北方冬季寒冷 ,栽培的粳稻种子在田间自然越冬翌年春季不能发芽出苗。但近几年在辽宁稻区出现了一种以杂草形式生存的一年生北方野生稻 ,这种北方野生稻农民称其为“疯稻子”。北方野生稻在田间生长繁茂 ,营养生长期与当地栽培稻不易区分 ,在出穗后才能鉴别。野生稻有普通野生稻、药用野生稻和疣粒野生稻三种类型。早在公元前 2 0 0年的《淮南子·泰族训》中就曾对南方的野生稻有过记载。据推测它的产生是多年生野生稻与栽培稻渐渗杂交的结果。多年生野生稻生存通常…     

亚洲栽培稻两大亚种之间同工酶基因型的主要区别

选择亚洲重要稻作区的中国、日本、朝鲜、印度、泰国、缅甸、尼泊尔等地的栽培稻品种89份及野生稻与栽培稻的中间稻系14份为材料,根据形态进行分类并检测其同工酶。从结果看,Amp-2、Acp-1和Cat-1三个同工酶对于籼粳分类有重要的作用。     

湖南澧县八十Dang遗址古栽培稻的再研究

用多种方法对１９９７年湖南澧县八十Ｄａｎｇ遗址出土的７８２粒８０００年前的古栽培稻谷的粒形等性状分析研究，观察到该古栽培稻是一个具有广泛性状变异的不同于现代籼、粳、普通野生稻的近一稻偏籼型的独立复合群体，且在演化地位上具有原始性和过渡性的特征。初步认定其为一个完全无人工选择条件下长期演化而成的原始栽培稻类型。     

Conservation and utilization of rice genetic resources in China

Rice genetic resources presents variably in China. There are land races and wild species. cultivated lowland rice and upland rice, indica (Hsien) and japonica (Keng) riee. early, middle, and late rice as well as glutinous and non-glutinous rice. Up to February 2000, a total of 76, 646 rice accessions were catalogued,and 67. 444 base accessions were stored in the National Crop Gene Bank in the Institute of Crop Genetic Resources (ICGR) of the Chinese Academy of Agricultural Sciences, Beijing, China (Table 1). About 35,000 rice duplicates were stored in China National Rice Research Institute(CNRRI), Hangzhou, Zhejiang Province. China.     

水稻颖壳硅石的初步研究及其意义

水稻颖壳硅石的初步研究及其意义陈报章,王象坤（徐州师范学院区域发展研究所,徐州２２１００９;北京农业大学农学系．北京１０００９４）关键词：颖壳;形态鉴定：硅石：水稻起源ＡＰｒｅｌｉｍｉｎａｒｙＳｔｕｄｙｏｎＰｈｙｔｏｌｉｔｈｏｆＣａｒｙｏｐｓｅｓｏｆ...     

Application of Functional Markers to Identify Genes for Bacterial Blight Resistance in Oryza rufipogon

Field resistances of nine accessions of common wild rice (Oryza rufipogon Griff.) and one rice variety (IR24) were evaluated by using nine strains of bacterial blight pathogen (Xanthomonas oryzae pv. oryzae) from the Philippines. IR24 was highly susceptible to all the strains, and six common wild rice accessions resisted all the nine strains, with a resistance frequency of 67%. The accessions Yulin and Wanning were only susceptible to PXO280 and PXO71, respectively. The accession Gaozhou was susceptible to the three strains PXO79, PXO99 and PXO339, whereas resistant to the other six strains. It could be concluded that there is at least one resistance gene in each common wild rice accession. The functional markers of the genes xa5, xa13, Xa21 and Xa27 were used to detect the presence of these resistance genes in the nine tested wild rice accessions, and it was found that four wild rice accessions contained heterozygous xa13. Among the nine common wild rice accessions, five were homozygous for Xa27 and three homozygous for xa27, and the accession Laibin contained neither xa27 nor Xa27. In addition, there were no xa5 and Xa21 in all of these accessions.     

温度对不同叶龄长雄野生稻及其后代化感作用的影响

掌握温度对长雄野生稻(Oryza longistaminata)及其后代化感作用的影响,对开发利用野生种质资源的化感抗草基因具有重要意义。采用直接树脂吸收法收集不同叶龄长雄野生稻及其后代在各温度条件下的根系分泌物,并以稗草作为受体,测定其化感作用。结果表明:1)温度、叶龄和温度×叶龄对水稻化感作用的影响与其自身化感潜力正相关,且对强化感和中化感潜力水稻(OL、F1、RL159和RL169)的化感作用影响极显著,而对弱化感水稻(RD23和RL219)的化感作用影响不显著。2)供试条件下长雄野生稻及其后代根系分泌物对稗草的化感作用均为抑制作用,其中,低温不利于水稻化感潜力的发挥。15℃时,强和中化感潜力水稻在不同叶龄对稗草的苗高、根长和生物量的抑制作用最弱,化感综合效应指数也显著大于同等叶龄的高温处理。3)高温有利于水稻化感潜力的发挥,但并非总是随温度的升高而增强。在6叶期和8叶期,水稻材料OL、F1、RL159和RL169随温度的升高化感作用逐渐增强,但在2叶期和4叶期则表现为先增强后减弱,在25℃时对稗草化感作用最强。4)在15℃时,强和中等化感潜力水稻在2叶期化感作用最弱,而在其他温度条件下,其化感作用随叶龄的增加表现为先减弱后增强,在2叶期化感作用最强。研究结果显示,温度对不同叶龄的水稻化感作用具有调控作用,幼苗阶段高温有利于强和中化感潜力水稻化感作用的发挥。     

A nucleotide substitution at the 5′ splice site of intron 1 of rice HEADING DATE 1(HD1) gene homolog in foxtail millet,broadly found in landraces from Europe and Asia

We investigated genetic variation of a rice HEADING DATE 1(HD1) homolog in foxtail millet.First, we searched for a rice HD1 homolog in a foxtail millet genome sequence and designed primers to amplify the entire coding sequence of the gene. We compared full HD1 gene sequences of 11 accessions(including Yugu 1, a Chinese cultivar used for genome sequencing) from various regions in Europe and Asia, found a nucleotide substitution at a putative splice site of intron 1, and designated the accessions with the nucleotide substitution as carrying a splicing variant. We verified by RT-PCR that this single nucleotide substitution causes aberrant splicing of intron 1. We investigated the geographical distribution of the splicing variant in 480 accessions of foxtail millet from various regions of Europe and Asia and part of Africa by d CAPS and found that the splicing variant is broadly distributed in Europe and Asia. Differences of heading times between accessions with wild type allele of the HD1 gene and those with the splicing variant allele were unclear. We also investigated variation in 13 accessions of ssp. viridis, the wild ancestor, and the results suggested that the wild type is predominant in the wild ancestor.     

利用CRISPR/Cas9技术编辑粒长基因GS3改善粳稻花时

【目的】花时不遇是影响杂交水稻制种产量的直接因素之一,已有研究表明水稻粒型差异对花时有影响。本研究采用GS3功能缺失突变来研究粳稻花时差异,以期为粒型影响花时提供佐证。【方法】利用CRISPR/Cas9技术来定向编辑控制粒长基因GS3,获得13对粒型差异的近等基因系粳稻,小区种植,采用目测法来调查花时。【结果】获得转基因T0植株并对其T1植株测序分析,发现长白25、吉粳102、浙粳88、武运粳27和J42均发生单碱基插入移码突变,垦鉴稻6号、空育131、浙粳22、扬粳4227、南粳9108、J5933、J6167和J5938均发生部分碱基缺失突变。对T1植株粒型考查表明,gs3突变体的粒长均显著长于野生型。对稳定的后代花时统计分析发现,粒型变长的突变体均比野生型花时有所提前,且吉粳102、空育131、浙粳88、武运粳27、扬粳4227这5个材料的gs3突变体花时均显著早于野生型,其余材料开花也提早,但不显著。【结论】长粒型粳稻GS3突变体的花时早于短粒粳稻野生型,这一研究可为粳稻粒型育种提供参考,加速长粒粳稻亲本选育,有望推动杂交粳稻发展。     

Genetic Diversity of Rice Landraces from Lowland and Upland Accessions of China

Genetic diversity of rice landraces from lowland and upland accessions of China was investigated using 66 polymorphic simple sequence repeat (SSR) markers.The total number of alleles detected from all 324 tested accessions was 555 with an average allele number (Na) of 8.409 per locus,the average effective number of alleles (Ne) of 3.574 and the average Shannon’s information index (I) of 1.378.The genetic diversity was higher for the indica landraces compared to the japonica landraces,and the upland landraces were more genetically diverse than the lowland landraces.The SSR markers,RM72,RM232,RM219,RM241,RM224 and RM3 showed the highest rates of polymorphism and these SSR markers were suitable to assess the genetic diversity of rice germplasm resources.A dendrogram of 324 accessions of lowland and upland landraces showed that all rice accessions were mainly subdivided into two groups,japonica and indica,with some being intermediate.The distribution of lowland and upland landraces among the japonica and indica rice groups was distinct,with obvious differentiation between the lowland and upland landraces in japonica rice,but no such clear distinction in indica rice.