香稻种质资源筛选及香味基因遗传研究

本试验采用KOH浸泡法和香味功能标记对144份水稻品种进行香稻种质资源的筛选,同时以2个杂交组合平粳11/黑香稻、吉林日落/黑香稻的F:群体为试验材料,对黑香稻香味基因进行遗传分析。结果表明,用KOH浸泡法筛选时,有20个水稻品种产生香味;用香味基因功能标记GRFM04筛选时,仅有17个含有香味基因。黑香稻,SY-香-7、清香糯用KOH法筛选产生香味,但用功能标记GRFM04检测为不含有香味基因。黑香稻的香味受1对隐性基因控制,在纯合基因型中水稻叶片的香味与米粒的香味呈高度一致性,但在杂合的基因型中,叶片无香的单株,其米粒有无香与有香的分离。     

几个香稻保持系香味的遗传研究

对四川省新选育的7个香稻保持系和1个引进改良的香稻品种的香味遗传和等位性进行了分析,同时,利用微卫星DNA标记对D香2 B和泸香90的香味基因进行了初步定位.结果显示,所有香稻品系(品种)与非香稻杂交,F1植株的叶片均无香味,显示出香味由隐性基因控制;从香与香杂交F1植株、回交BC1F1和F2群体分析看,D香1 B、D香2 B、内香2 B、内香4 B、绵香2 B、绵香3 B、宜香1 B的香味受单隐性基因所控制;泸香90的香味可能受一对抑制基因和一对香味基因控制.初步将D香2 B和泸香90的香味基因定位在第八染色体上,D香2 B香味基因位点与SSR引物RM 210相距17.3 cM,与RM 515相距5.7 cM;泸香90的香味基因位点与RM 515相距4.3 cM.RM 515可应用于水稻分子育种实践.     

‘泰国小香占’香味基因的鉴定和功能分子标记的开发

香稻育种已成为当前杂交水稻育种的一个重要方向,选择和利用株型好、米质优、抗性强等综合性状优良且具有香味的水稻亲本,尤其是香型水稻恢复系亲本的利用,对进一步促进杂交水稻香稻的选育具有重要意义。‘泰国小香占’是目前国内水稻香稻育种中应用较广且综合性状优良的恢复系亲本,其米质优、抗性强、香味浓。为了探究‘泰国小香占’香味产生的原因,本研究鉴定了‘泰国小香占’的香味基因及其突变类型,发现其香味来源于编码甜菜碱脱氢酶基因Badh2的功能缺失突变,且通过对该基因完整基因组序列扩增和测序分析发现其等位突变类型为badh2-E7类型,即在第7外显子处存在8 bp缺失和3个单核苷酸位点多态性突变(SNPs)。通过气相色谱-质谱联用技术(GC-MS)测定其籽粒中香味物质2-乙酰-1-吡咯啉(2-AP)的含量为0.108 mg/kg,明显高于非香味品种‘日本晴’和‘9311’的含量(0.01 mg/kg)。实验还证明了特异性分子标记FMbadh2-E7、InDel-E7以及自主开发设计的特异性功能标记FMbadh2-E7A和FMbadh2-E7B均可高效、准确鉴别出非香纯合(Badh2/Badh2)、非香杂合(Badh2/badh2)和香味纯合(badh2/badh2) 3种基因型。同时本研究还进一步通过对‘泰国小香占’和非香味水稻品种杂交F2代单株进行了基因型和遗传规律分析,发现其基因型Badh2/Badh2:Badh2/badh2:badh2/badh2的比例为1∶2∶1,符合孟德尔细胞核单基因控制分离比。本研究通过对‘泰国小香占’香味基因的鉴定、遗传特性分析以及特异性功能分子标记的开发和验证,为进一步通过分子标记辅助选择育种技术,应用‘泰国小香占’香味基因培育优质、高产且抗性强的杂交水稻香稻提供了重要的理论基础。     

新型香稻渝恢2103香味分子遗传特性分析

香味是优良稻米品质的重要衡量标准之一,2-乙酰-1-吡咯啉(2AP)是最主要的香味物质,然而2AP生物合成机理至今仍未确凿。本研究筛选了与2AP生物合成密切相关的甜菜碱脱氢酶2基因(Badh2)在30份水稻材料中的3种突变类型,从中发现1份新的香稻材料渝恢2103,该材料Badh2基因序列编码区无突变,遗传分析显示渝恢2103与badh2-E7突变型香稻宜香1B香味基因不等位,与非香稻杂交F2香与非香分离比接近9∶7,与香稻杂交F2香与非香分离比接近7∶9,表明渝恢2103的香味受多基因控制。进一步利用实时荧光定量PCR技术(qRT-PCR)比较了与2AP生物合成相关基因在日本晴、渝恢2103和宜香1B的表达情况,结果显示,Badh2基因在日本晴和渝恢2103中表达差异不大,但在宜香1B中表达量异常高;多数脯氨酸与谷氨酸代谢途径相关基因在宜香1B中的表达水平显著高于日本晴和渝恢2103;推测宜香1B的2AP合成同时受Badh2基因以及脯氨酸与谷氨酸代谢途径相关基因的影响;渝恢2103香味形成可能与这些基因无必然联系。渝恢2103特殊的遗传特性可能为水稻香味形成机理研究提供新的突破点。     

基于PCR/LDR技术的水稻香味等位基因Badh2-E2功能性分子标记

水稻中水稻甜菜碱醛脱氢酶(BADH2)功能缺失导致其酶促反应的底物2-乙酰-1-吡咯啉(2AP)的累积,使得稻米产生香味。水稻香味等位基因badh2-E2在中国的香稻育种中有较广泛的应用。本研究根据badh2-E2香味等位基因在第二外显子处7 bp缺失,设计了一个基于PCR/LDR技术的功能性分子标记。利用PCR/LDR标记对‘申繁24’、‘申恢26’,及其杂交F_1代的基因型进行鉴定,可以准确地鉴定出badh2-E2位点的基因型。用PCR/LDR标记对杂交F_2代群体的基因型进行鉴定,发现badh2-E2阳性纯合型、杂合型和badh2-E2阴性纯合型这3种基因型符合1∶2∶1分离比。本研究结果为标记辅助育种提供了一种新的标记类型,具有一定的应用价值。     

香型优质杂交稻米质现状及改良思考

笔者于1973年育成了V20不育系,推广面积虽大,但米质较差,改良稻米品质就成为了笔者多年的育种目标。1984年利用优质稻资源MR365和其后利用其衍生系作亲本开展了香稻不育系及其香型杂交稻的选育。用香稻不育系与非香的恢复系配组的方式育成香型杂交稻。它具有不同于普通常规香稻品种,其植株是非香的,而植株上结籽粒仅有一小部分具有香味。这种类型的香稻稻米恰好符合人们的饮食习惯。迄今为止,香稻不育系更替了4代,并配制出了一大批香型杂交稻组合,这些组合的米质和产量都有了大幅提高。     

不同来源水稻品种badh2基因的同源性分析

香味基因是香稻育种的关键。本研究采用香味基因Xiang7F/7R对来源于辽宁省农科院和牡丹江市场的9个水稻品种进行序列分析。结果表明:(1)9个水稻品种在近400 bp处均出现一条带。(2)序列同源性分析发现,稼禾1号和龙粳香1号出现8 bp的片段缺失和3 bp的碱基突变。(3)日本晴与NCBI上发布的日本晴在该基因位点上存在5个碱基的插入/缺失,同源相似性达到99%。(4)遗传距离和系统发育树均表明,稼禾1号和龙粳香1号的遗传距离为0,聚为同一分支。以上结果表明,香味基因对不同水稻品种具有较高的灵敏度,可用于香稻品种的筛选,进而为后续的香稻品种选育奠定基础。     

优质杂交香稻--香优1号

杂交水稻香优1号，系四川省农科院作物所用自育香型不育系川香28A与恢复系CDR22测配而成的优质杂交香稻。1995年5月通过四川省农作物品种审定委员会审定并列入农业部跨越计划主推优质组合。     

优质杂交香稻香优1号

杂交水稻香优1号系四川省农科院作物所，用自育香型不育系川香28A与恢复系CDR22测配而成的优质杂交香稻。1999年5月通过四川省农作物品种审定委员会审定并列入农业部跨越计划主推优质组合。     

优质杂交香稻香优1号

杂交水稻香优1号系四川省农科院作物所，用自育香型不育系川香28A与恢复系CDR22测配而成的优质杂交香稻。1999年5月通过四川省农作物品种审定委员会审定并列入农业部跨越计划主推优质组合。     

Trisomic genetic analysis of aroma in three Japanese native rice varieties (Oryza sativa L.)

Information on the genetics of aroma in rice facilitates breeding and selection of new aromatic varieties with high yield and good quality. Objective of the present study was to make clear the number of genes controlling aroma, and the allelism of aroma genes and the location of aroma gene(s) on the chromosome in three Japanese native aromatic rice varieties (Kabashiko, Shiroikichi and Henroyori). Lack of leaf aroma in all F₁ plants of non-aromatic/aromatic crosses indicated the recessive nature of aroma, and the segregation ratios (3:1) of non-aromatic to aromatic plants in its F₂ populations from Nipponbare/aromatic varieties crosses revealed that each of the three aromatic varieties contains a single recessive gene for aroma. Through trisomic analysis, the segregation of non-aromatic and aromatic plants in all F₂ populations from the crosses between trisomics lines NT8, with an extra chromosome 8, and aromatic varieties deviated significantly from disomic segregation of 3:1 ratios, and fitted to trisomic segregation, however, in other F₂ populations derived from other 7 types of trisomic F₁ plants, the segregation ratios of non-aromatic to aromatic were 3:1, indicating that the single recessive aroma gene was located on chromosome 8 in three aromatic varieties. This revised version was published online in July 2006 with corrections to the Cover Date.     

High embryo sac fertility and diversity of abnormal embryo sacs detected in autotetraploid indica/japonica hybrids in rice by whole‐mount eosin B‐staining confocal laser scanning microscopy

An eosin B staining procedure for use with confocal microscopy (WE‐CLSM) was used to examine the mature embryo sacs in 24 typical autotetraploid (2n = 4x = 48) indica/japonica hybrids and to compare with their original diploid (2n = 2x = 24) indica/japonica hybrids in rice. Four of the 24 hybrids showed >80% embryo sac fertility, and 13 hybrids over 70%. The average embryo sac fertility of the 24 autotetraploid indica/japonica hybrids was 68.08%, which was 17.33% higher than that in diploid hybrids. When compared with the diploid hybrids, 79.17% of the autotetraploid hybrids had higher embryo sac fertility. A diversity of abnormal embryo sacs occurred in autotetraploid indica/japonica hybrids. Embryo sac abnormalities were similar for both autotetraploid and diploid hybrid, but their frequencies were different. Some novel abnormal types were found in autotetraploid hybrids, such as enlarged egg apparatus. The embryo sac fertilities and frequencies of various abnormalities in autotetraploid hybrids varied with parental genotype and environment. The average seed set of the autotetraploid hybrids were higher than their diploid hybrids in different growing seasons.     

Inheritance of aroma in rice

Summary Inheritance of an aroma was worked out in crosses between Brimful from Nepal as an aromatic rice and leading Japanese varieties Koshihikari and Nipponbare as non-aromatic ones. The F₂ pattern of segregation for aroma to non-aroma was 3:13 indicating one dose gene for aroma and one dose inhibitor gene in two crosses. This ratio was confirmed by genetic behavior of F₃ populations.     

Autotetraploidy in caraway (Carum carvi L.) for the increase of the aetheric oil content of the seed

Summary An autotetraploid population of caraway (Carum carvi L.) was produced by treating the growing points of young plants with a 0.2% colchicine solution. Selection on morphology, pollen size and pollen shape, followed by a selection on seed size proved to be an effective way to identify the mixoploid C₀ plants. Three percent of the treated plants produced a tetraploid progeny. Moderate selection in the C₁ and the C₂ population resulted in an improvement of the average seed-set to the amount of 50% of the diploid control, with a range of 21–78%. The 1000-kernel weight of the tetraploid material was 7 g, compared to 3 g in the diploid control. The oil content of the autotetraploid seed was increased with 35.6%; the increase in carvone amounted to 6.9%. The results of the experiment indicate that breeding work in autotetraploid caraway may result in a new cultivar.     

同源四倍体水稻与假稻杂交结籽的胚胎学机理研究

利用激光扫描共聚焦显微技术对同源四倍体水稻与假稻杂交结籽的特殊生殖现象进行了研究.研究结果表明,假稻的花粉粒不能在二倍体水稻的柱头上萌发,因而二倍体水稻与假稻的生殖隔离很严格.然而,假稻的花粉粒在同源四倍体水稻的柱头上能萌发,前者的花粉管能在后者的花柱中伸长并能将雄配子送入胚囊内.在同源四倍体水稻与假稻的     

同源四倍体高粱不育系和保持系的生物学及生理特性研究

以二倍体高粱不育系及其保持系和由它们诱变成的同源四倍体选系为材料, 研究 了同源四倍体不育系和保持系的生物学特征及生理特性, 结果发现, 四倍体的株高一般为 二倍体的80.6％～90.1％, 单株总叶片数减少1～2片; 保持系加倍后, 顶部三叶面 积增 加4.6％～9.4％; 不育系的花药由二倍体时的白色变为四倍体的淡黄色,     

西洋梨二倍体及其人工诱导同源四倍体遗传差异的SSR分析

以西洋梨‘丰产’二倍体及其10个同源四倍体株系为材料,通过微卫星(SSR)分子标记技术对西洋梨二倍体与同源四倍体之间的遗传差异性进行了研究。应用10对SSR引物对11份材料进行扩增,共扩增出23条谱带,其中有8条呈多态性,多态性比例为34.78%;10对引物中有3对引物为多态性引物。聚类分析显示,不同同源四倍体株系与二倍体的遗传差异大小亦不同;在10个同源四倍体株系中有3个株系扩增的条带与二倍体完全相同,7个同源四倍体株系与二倍体相比产生了差异性条带。研究结果表明,西洋梨二倍体与其同源四倍体之间以及10个同源四倍体株系之间在DNA水平上表现出了一定的多态性。本研究能够为进一步进行西洋梨多倍体的育种实践提供理论指导。     

Generation and characterisation of colchicine-induced autotetraploid Lavandula angustifolia

Lavandula angustifolia (lavender) is a small woody perennial grown for essential oil, which is steam distilled from flowers. To potentially improve size of flowers and oil yield we produced and characterised autotetraploid plants. L. angustifolia seed germinated in the presence of the mitotic spindle inhibitor colchicine at concentrations of 125 mg l⁻¹ or less resulted in plants carrying sports with larger flowers. Propagation of two sports gave rise to putative polyploid cultivars C3/2 and C6/24. Direct chromosome counts in root tip cells of seedlings from four common cultivars of L. angustifolia and the seed lot from which C3/2 and C6/24 were derived was 50 whereas C3/2 and C6/24 had greater than 90 chromosomes indicating they were autotetraploid. Ploidy level assessed by flow cytometry (FCM) of nuclei showed that 12 cultivars of L. angustifolia had similar nuclear DNA content whereas C3/2 and C6/24 had double the amount of DNA confirming autotetraploidy. The genome size (1C-value) of a diploid L. angustifolia cultivar was estimated by FCM to be 0.90 (±0.07) pg. Morphological characteristics were measured in autotetraploid and control plants. Autotetraploids had thicker peduncles, larger flowers and larger seeds than diploids. Scanning electron microscopy revealed peltate glandular trichomes were larger in the tetraploids relative to diploids. Both tetraploid and diploid cultivars had complex non-glandular trichomes on leaves and sepals and two different types of capitate glandular trichomes were identified on leaves. Autotetraploid lavenders represent useful germplasm both for commercial oil production and future breeding.     

同源四倍体水稻农艺性状的遗传分析

与二倍体水稻相比,同源四倍体水稻杂种具有强大的生物学优势,目前对同源四倍体水稻数量性状的遗传规律及存在较强优势的遗传基础还不清楚。此研究利用一套4×12不完全双列杂交的亲本和F1 2个世代的同源四倍体材料,采用加性-显性模型和统计分析方法,分析同源四倍体水稻农艺性状的遗传规律。结果表明,同源四倍体农艺性状受到遗传主效应与基因型×环境互作效应共同控制;其中株高、穗长以显性效应为主,剑叶宽以加性效应为主,有效穗数和剑叶长性状以显性×环境互作效应为主;株高、穗长和剑叶宽的HN和HB均分别比HNE和HBE大,表明这3个性状的选择效果受环境的影响较小;有效穗数和剑叶长的HN相对较小,HNE相对较大,说明这两个性状的选择效果因环境而不同。此研究为在杂种配制和后代选择中有效地利用同源四倍体新种质提供理论依据。     

不同倍性田埂报春DNA含量和叶绿素荧光特性研究

研究旨在以田埂报春二倍体及经秋水仙素加倍获得的同源四倍体为材料,比较2种倍性植物叶片DNA含量和叶绿素荧光参数的日变化规律。采用流式细胞测定法和叶绿素荧光技术进行测定,结果显示：（1）四倍体叶片细胞DNA的相对含量为二倍体的2倍。（2）四倍体的叶绿素a、b、总含量及类胡萝卜素含量都高于二倍体。（3）四倍体与二倍体的叶绿素荧光参数PSⅡ的原初光能转化效率(Fv/Fm)、 PSⅡ的潜在光化学效率(Fv/Fo)和以吸收光能为基础的光合性能指数(PI)值的日变化趋势相似,但四倍体的Fo小于二倍体。叶绿素总含量及类胡萝卜素含量、最大荧光、光化学效率、PSⅡ潜在活性和光性能指数均大于二倍体,田埂报春四倍体植株表现出优良的光合性能。