水稻抗褐飞虱基因及其育种应用研究进展

褐飞虱是危害水稻生产最重要的害虫之一。遏制水稻褐飞虱为害的最安全、有效的措施既利用水稻自身的抗虫性。迄今为止,已经于栽培稻和野生稻中成功鉴定出30个水稻抗褐飞虱基因,其中26个主效抗性基因已被定位,显性基因Bph14已成功克隆,但仅少量主效抗性基因被育种家利用并培育出抗性品种。对褐飞虱的生物型和抗性机理、水稻抗褐飞虱的遗传基础及育种应用研究进行了综述,并就今后的抗性育种研究趋势展开了讨论。     

水稻抗褐飞虱基因及其利用现状研究

褐飞虱是危害水稻生产最重要的虫害之一.自20世纪70年代以来,国内外相继开展了水稻褐飞虱抗性基因的发掘工作.迄今已确认和报道的水稻抗褐飞虱基因共27个,其中16个为显性基因,11个为隐性基因,至少定位了19个褐飞虱主效抗性基因.针对目前水稻抗褐飞虱育种存在的问题,结合稻褐飞虱生物型、水稻品种的遗传背景及生态适应性,本文综述了水稻抗褐飞虱基因资源的鉴定、其分布特点以及水稻品种对褐飞虱的抗虫机制,简述了抗褐飞虱基因的育种利用现状,讨论了抗褐飞虱育种中存在的问题及其应用前景.     

东乡野生稻抗褐飞虱QTL分析

野生稻是水稻抗褐飞虱基因的重要种质资源。应用东乡野生稻与栽培稻协青早B构建的2套材料,开展水稻抗褐飞虱基因鉴定研究。先以协青早B//协青早B/东乡野生稻BC₁F₅群体为材料,应用褐飞虱田间种群进行抗虫鉴定,检测到2个抗褐飞虱QTL,其中,qBph2位于水稻第2染色体RM29–RG157区间,东乡野生稻等位基因可降低死苗率22.2%;qBph7位于第7染色体RM11–RM234区间,东乡野生稻等位基因可降低死苗率43.7%。进一步以协青早B为轮回亲本,构建了BC₃F₃群体,应用褐飞虱生物型I、II和III进行抗虫鉴定,QTL分析表明qBph2抗褐飞虱生物型I和II,qBph7抗褐飞虱生物型I和III。这2个QTL对培育抗褐飞虱水稻品种具有重要应用价值。     

利用RFLP／AFLP构建水稻褐飞虱抗性基因Bph1的连锁图

褐飞虱(Nilaparvata lugens Stal)是水稻最严重的害虫之一。已有人探索和利用天然抗性系统解决水稻生产中的褐飞虱问题。到目前为止，在本地籼稻品种和两个野生近缘种澳洲野稻和药用野生稻中鉴定到至少12个褐飞虱抗性主基因。     

培育水稻恢复系抗稻褐飞虱基因导入系和聚合系

稻褐飞虱是水稻的主要虫害之一,培育优良的抗性基因聚合系对于防治稻褐飞虱具有重要的意义.本研究通过回交、分子标记辅助选择和接虫鉴定三者相结合的办法,将抗稻褐飞虱基因Bph3和Bph24(t)分别导入主栽杂交水稻恢复系广恢998、9311、R15、明恢63、R29中,最终获得遗传稳定的Bph3导入系32份和Bph24(t)...     

水稻抗褐飞虱育种研究的现状与展望

褐飞虱是中国夏季水稻生产的主要害虫之一。选育与利用抗性品种被认为是控制水稻褐飞虱为害的有效途径之一。研究综述了稻褐飞虱的生物型/致害型、抗褐飞虱基因,着重介绍了中国抗褐飞虱育种的研究现状,并对今后的抗性育种研究提出了几点建议。     

分子标记辅助选择抗褐飞虱基因改良桂农占的BPH抗性

本研究通过分子标记辅助选择和连续回交的方法将来源于栽培稻的抗褐飞虱基因Bph3、来源于野生稻的抗褐飞虱基因Bph14和Bph15分别转入到华南高产水稻品种桂农占中,在BC3F3获得了含单个抗性基因的稳定株系和含Bph14和Bph15的稳定株系,其遗传背景与桂农占相似达95%以上。这些株系苗期对褐飞虱的抗性评价表明,在含单个抗性基因的株系中,含Bph3的株系抗性水平最高,含Bph14的最低,而含Bph14和Bph15的株系抗性水平高于含单个基因的株系。对农艺性状的调查发现,含抗性基因的株系与桂农占在抽穗期方面表现出显著差异。在单株产量方面,含抗褐飞虱基因的株系与桂农占没有显著差异。研究结果可为培育抗褐飞虱基因高产水稻品种提供材料。     

标记辅助培育水稻抗稻褐飞虱和稻白叶枯病基因聚合系

稻白叶枯病和稻褐飞虱是水稻的主要病虫害,利用优良的抗性基因培育抗性基因聚合系对于防治稻白叶枯病和稻褐飞虱具有重要意义。本研究通过回交与分子标记辅助选择相结合的方法,将抗稻白叶枯病基因Xa23和抗稻褐飞虱基因Bph3分别导入主栽杂交水稻品种的保持系先B、天B、盟B、龙特甫B和桂B中。结果表明,获得稳定的单抗性基因导入系1436份和双抗性基因聚合系144份。人工接种鉴定结果显示,Xa23导入系和Xa23Bph3聚合系对抗稻白叶枯水平达到中抗和接近高抗的水平(1.1～3.0级),Bph3导入系和Xa23Bph3聚合系抗褐飞虱水平达中抗到抗的级别(3.2～4.0级)。农艺性状分析显示多数抗性基因聚合系的株高、剑叶长宽度、每穗粒数、结实率、千粒重等主要农艺性状与受体差异不显著,只有少数聚合系有1～2个性状的差异。SSR标记分析表明抗性基因聚合系的遗传背景回复率达89.6%～97.8%,等位性位点纯合度达95.6%～99.9%。初步证明本研究已成功地获得抗稻白叶枯病和稻褐飞虱基因的聚合系,这些抗性改良保持系具有良好的应用前景,并为建立完善的分子设计育种平台提供了重要育种材料基础。     

阔叶野生稻对四种主要害虫的抗性评价

采用国际通用的抗虫性评价方法，用华南４种主要水稻害虫对１５１份阔叶野生稻Ｏ．ｌａｔｉｆｏｌｉａ作抗性评价，取６个不同类型的材料进行对两种飞虱的抗性机制分析。结果认为：阔叶野生稻对褐稻虱ＮｉｌａｐａｒｖａｔａＬｕｇｅｎｓ高抗，优于抗性对照品种ＩＲ３６，抗性机制主要是非嗜食性；对白背飞虱中抗；对三化螟和稻瘿蚊则高感。     

水稻的远缘杂交

稻属野生种是为水稻品种改良提供许多有用性状的来源。将具有AA染色体组的野生种基因转移到栽培水稻中去是较容易的,具有BB、CC、DD和EE染色体组的野生种和栽培水稻杂交是困难的,我们试图在18个药用野生稻样本和三个栽培水稻育种品系之间进行杂交。具有CC染色体组的药用野生稻,高抗褐飞虱(BPH)、白背飞虱(WBPH)和叶蝉。     

Genetic mapping of bph20(t) and bph21(t) loci conferring brown planthopper resistance to Nilaparvata lugens St?l in rice (Oryza sativa L.)

Brown planthopper(BPH) is one of the most serious and destructive insect pests of rice in most rice growing regions of the world. In this study, two major resistance genes against BPH have been identified in an Oryza rufipogon (Griff.) introgression rice line, RBPH54. Inheritance of the BPH resistance in RBPH54 was studied by screening the resistance in parents, F1, F2 and BC1 generations against BPH biotype 2. A population of BC3F2 lines was developed and SSR markers were employed for the gene mapping, and new markers were designed for fine mapping of the resistance genes, while sequence information of BAC/PAC clones was used to construct physical maps of the genes. The results showed that the BPH resistance in RBPH54 was governed by recessive alleles at two loci, tentatively designated as bph20(t) and bph21(t). The locus bph20(t) was fine mapped to the short arm of chromosome 6 about 2.7 cM to the upper marker RM435 and 2.5 cM to lower marker RM540 and in a 2.5 cM region flanked by two new SSR markers BYL7 and BYL8 which were developed in the present study. The other BPH resistance locus bph21(t) was initially mapped to a region 7.9 cM to upper marker RM222 and 4.0 cM to lower marker RM244 on the short arm of chromosome 10. For physical mapping, the bph20(t)-linked markers were landed on BAC/PAC clones of the reference cv., Nipponbare, released by the International Rice Genome Sequencing Project. The bph20(t) locus was physically defined to an interval of about 75 kb with clone P0514G1. Identification and location of these two genes in the present study have diversified the BPH resistance gene pool, which give benefit to the development of resistant rice cultivars, and the linkage PCR-based SSR markers for the bph20(t) and bph21(t) genes would help realize the application of the genes in rice breeding through marker-assisted selection.     

华南抗稻瘿蚊分子标记辅助育种

亚洲稻瘿蚊(Orseolia oryzae Wood-Mason)是华南的主要水稻害虫.选育抗虫品种是最有效的生态控制方法.本文综述1998-2006年抗性育种的进展.用AFLP方法对从中国广东省7个地点采集的4个生物型的DAN指纹进行分析;在对用RAPD和SSR技术分别对抗中国4个稻瘿蚊生物型的基因Gm6精细定位基础上,用与Gm6紧密连锁的STS和SSR标记开展分子标记辅助育种,创造了一批抗稻瘿蚊的新种质,包括育成了6个栽培稻和6个二系杂交稻和1个三系杂交稻并在农户试种,在中国广东成功地建立了分子标记辅助选育抗稻瘿蚊品种的技术体系.     

水稻抗白叶枯病新基因Xa32（t）的鉴定和初步定位

通过多菌系接种鉴定及抗谱分析,并与目前国际上已知抗白叶枯病基因比较,证明在水稻抗源C4064中含有一个新的抗白叶枯病基因,暂命名为Xa32(t)。应用分离集团分析法(BSA),借助SSR和EST等分子标记,对该基因进行了分子标记定位。通过对F₂分离群体及F₃家系单株进行遗传连锁性检测,发现6个位于水稻第11染色体长臂末端的分子标记RM27256、RM27274、RM2064、ZCK24、RM6293和RM5926与Xa32(t)基因连锁。它们与Xa32(t)基因间的遗传距离分别为2.1、1.0、1.0、0.5、1.5和2.6 cM。其中标记RM6293和RM5926位于染色体近端粒一侧,其他4个标记RM27256、RM27274、RM2064和ZCK24位于基因的另一侧。将Xa32(t)定位在水稻第11染色体长臂末端2.0 cM范围内。     

A new locus for resistance to brown planthopper identified in the indica rice variety DV85

The brown planthopper (BPH) is one of the most destructive insect pests of rice. Resistant varieties have proved to be one of the most economic and effective measures for BPH management. In this study, an indica rice ‘DV85’ showed resistance to biotype 2 of BPH by bulked seedling test, and a recombinant inbred line (RIL) population derived from a cross between a susceptible rice ‘Kinmaze’ and ‘DV85’ was phenotyped to map genetic factors conferring BPH resistance in ‘DV85′. Composite interval mapping revealed that one quantitative trait locus (QTL) with a LOD score of 10.1 was detected between XNpb202 and C1172 on chromosome 11. This QTL was designated as Qbph11. Qbph11 explained 68.4% of the phenotypic variance of BPH resistance in this population. The allele from the resistant parent ‘DV85’ at Qbph11 reduced the damage caused by BPH feeding and would be very useful in breeding resistant rice varieties via marker‐assisted selection.     

水稻抗白叶枯病新基因Xa32（t）的鉴定和初步定位

通过多菌系接种鉴定及抗谱分析,并与目前国际上已知抗白叶枯病基因比较,证明在水稻抗源C4064中含有一个新的抗白叶枯病基因,暂命名为Xa32(t)。应用分离集团分析法(BSA),借助SSR和EST等分子标记,对该基因进行了分子标记定位。通过对F₂分离群体及F₃家系单株进行遗传连锁性检测,发现6个位于水稻第11染色体长臂末端的分子标记RM27256、RM27274、RM2064、ZCK24、RM6293和RM5926与Xa32(t)基因连锁。它们与Xa32(t)基因间的遗传距离分别为2.1、1.0、1.0、0.5、1.5和2.6 cM。其中标记RM6293和RM5926位于染色体近端粒一侧,其他4个标记RM27256、RM27274、RM2064和ZCK24位于基因的另一侧。将Xa32(t)定位在水稻第11染色体长臂末端2.0 cM范围内。     

Search for novel genes for resistance to powdery mildew (Sphaerotheca fuliginae) in cucumber (Cucumis sativus)

Summary The current powdery mildew (Sphaerotheca fuligninea) resistant cucumber varieties suffer from leaf chlorosis during autumn, winter and early spring cultivation in the Netherlands. Therefore screening was carried out for novel powdery mildew resistance genes. From 177 accessions, derived from different sources, 108 accessions proved to be partially resistant to S. fuliginea. Crosses were made with 53 resistant accessions to distinguish the presence of novel genes. It is likely that the accessions C. sativus 2145, C. sativus LV 41, PI 188807, Vladivostokij, White and Yellow 1 have one or more recessive powdery mildew resistance genes, different from powdery mildew resistance genes of the line NPI, which was used for variety breeding. Powdery mildew resistance tests with S. fuliginea give similar results in different regions of the world.Abbreviations pmr powdery mildew resistance     

Exploring genetic diversity of rice cultivars for the presence of brown planthopper (BPH) resistance genes and development of SNP marker for Bph18

Brown planthopper (BPH) is the most devastating insect pest in rice‐growing areas. Information on availability of BPH resistance alleles and their sources enhances BPH‐resistant breeding programmes. In this study, 260 highly diversified rice cultivars or breeding lines were screened for the presence of five major BPH resistance genes (Bph10, Bph13, Bph18, Bph20 and Bph21) using gene‐specific markers. The analysis revealed that 137 of the 260 cultivars possess at least one BPH resistance gene. Bph10 was predominant while Bph20 was the least distributed. Moreover, two and three different resistance gene combinations were found in the cultivars. Molecular markers play an important role in molecular breeding programmes. A tightly linked PCR‐based co‐dominant Bph18 marker was developed, which is cost effective and time effective and simpler than available Bph18 CAPS marker (7312.T4A). We strongly believe that the identified BPH‐resistant cultivars can be used as alternative resistance gene sources and also as resource for novel BPH resistance genes. The developed Bph18 marker will be highly useful in molecular breeding applications of BPH‐resistant breeding programmes.