平湖剑子麦、洪湖大太宝、崇阳红麦、延岗坊主、万年2号抗赤霉病性基因分析

本试验将抗性组分分析法与单体分析法相结合,进行了小麦抗性基因染色体定位和抗性评价。结果表明,平湖剑子麦是抗性较稳定的中抗至抗病品种,其抗性基因涉及6D、7A、3B、5B和6B 等染色体。洪湖大太宝抗性基因和感病基因并存,是一个中抗偏感或中感品种。崇阳红麦属感病品种。延岗坊主的抗性基因位于染色体3A 上,感病基因位于5D 上,是一个中抗品种.万年2号麦穗前期抗病基因位于4D 和5A 上,是中抗品种。两种方法结合研究多基因控制的赤霉病抗性,能获得比较准确的结果和较多的遗传信息。     

黑龙江省主栽水稻品种抗稻瘟病基因的分子检测与分析

了解品种本身的抗性基因型对于水稻品种合理布局具有重要意义。为了明确稻瘟病抗性基因Pi-ta、Pi-b、Pik-m、Pi9、Pii、Pi-d3在黑龙江省水稻品种中的分布情况,选取34份主栽品种,利用这6个抗瘟基因的功能标记,对供试材料进行分子标记检测。结果表明,Pi9的分布频率最高,其次是Pi-ta和Pik-m,Pi-b和Pii抗性基因分布频率较低,Pi-d3的分布频率最低;供试的34份水稻材料中,被检测出最多含有5个抗性基因,而最少只含有1个抗性基因,含有2个抗性基因的品种所占比例最大,龙粳40和龙粳42不含有待检测基因。     

若干杂交稻组合对褐稻虱的抗性遗传测定

1984～1986年,用168个对褐稻虱抗性1～3级的东南亚血缘的水稻品种和38个抗性7～9级的品种作父本,用野败型不育系珍汕97A及红莲型不育系青四矮A作母本,组配303个组合。鉴定结果,抗性1～3级的组合共11个仅占3.6％,其中汕优早(珍汕97A×外选35)抗性3级,多抗性,丰产性较好,有推广价值;抗性5级丰产性又较好的组合有7个;抗性7～9级有262个。这些F_1各具不同的遗传背景,符合抗性遗传规律。试验结果认为:直接应用外引抗源组配成抗性组合,成功的可能很少。只有将抗性基因导入母本或将含有Bph_5或Bph_6显性抗性基因,能抗多个褐稻虱生物型的种质资源,进行广泛杂交,育成新的抗性品种再作恢复系或保持系才有可能组配出更多的抗褐稻虱的杂交稻组合。     

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。     

黄淮海地区大豆主栽品种对8个大豆疫霉菌株的抗性评价

随着麦茬免耕栽培技术的推广应用,黄淮海地区麦后夏播大豆生产中疫霉根腐病呈加重趋势。了解该地区大豆主栽品种对疫霉根腐病的抗性和筛选抗病亲本,对培育新的高产广适抗病品种具有重要意义。本研究利用8个具有不同毒力的大豆疫霉菌株,采用下胚轴创伤接种法,对20世纪50年代以来黄淮海地区审定、推广的140个大豆主栽品种进行接种鉴定。表明除6个品种对8个菌株均无抗性外,其余134个品种分别抗1~8个大豆疫霉菌株,占鉴定品种总数的95.7%,其中抗6~8个以上菌株的品种有83个,占鉴定品种总数的59.3%。以14个鉴别寄主的抗病反应型为参照,发现134个品种对8个大豆疫霉菌株共产生65种反应型,其中19个品种产生的5种反应型与已知单基因或2个单基因组合反应型相同;115个品种产生的60种反应型与含有已知单基因或2个单基因组合的反应型不同,推测可能含有新的抗病基因或基因组合。根据研究结果合理选择亲本,可培育出聚合多个抗性基因且综合性状优良的大豆新品种。     

水稻抗稻瘟病基因Bsr-d1的SNP区域在地方品种中的变异分析

为揭示地方水稻品种中稻瘟病持久抗性基因Bsr-d1序列变异类型,本研究以收集到的缅甸、老挝和越南共79份地方水稻品种为供试材料,设计抗稻瘟病Bsr-d1基因特异引物对Bsr-d1基因启动子功能位点区段进行PCR扩增及测序分析。研究表明,79份地方水稻均持有抗稻瘟病Bsr-d1或bsr-d1等位基因,品种间存在18个变异位点和22个碱基的差异,根据差异所有品种可归为6种单倍型,其中H4和H6为优势单倍型,分别占测试品种的20.25%、58.23%;6种单倍型中仅H3单倍型携带抗性位点,有8个材料归为此类型,占10.13%。缅甸地方品种拥有H1 (15.79%)、H2 (2.63%)、H3 (13.16%)、H4 (18.42%)、H6 (50%)等5种单倍型,优势单倍型为H6;老挝地方品种有H1 (2.56%)、H3 (7.69%)、H4 (23.08%)、H5 (2.56%)、H6 (64.10%) 5种单倍型,H6为优势单倍型,表明缅甸、老挝间在单倍型种类和抗性品种比例上均存在一定差异。本研究结果表明缅甸、老挝水稻资源携带持久抗性基因Bsr-d1的品种比例远高于中国品种,对中国选育稻瘟病持久抗性品种具有重要的利用价值,应加强对该地区种质的引进和分析评价。     

马铃薯病毒病抗性基因分子标记检测

马铃薯(Solanum tuberosum L.)是世界第四大重要的粮食作物,生长过程中其品质和产量会受到各种因素的影响,其中病毒病是影响最为严重的因素之一,给生产造成巨大损失。目前已知大约有40种病毒会感染马铃薯,对马铃薯的产量和品质影响最主要的病毒是马铃薯X病毒(PVX)、马铃薯Y病毒(PVY)和马铃薯卷叶病毒(PLRV)。马铃薯中含有对PVX具有极端抗性的基因Rx1、对PVY具抗性的基因Ry_(adg)、Ry_(sto)、Ry_(chc)和对PLRV具抗性的基因PLRV.1,聚合抗性基因是防治PVX、PVY以及PLRV对马铃薯生产影响最有效的策略。本研究利用与抗性基因Rx1、Ry_(adg)、Ry_(sto)、Ry_(chc)和PLRV.1紧密相连的分子标记Rxsp、RYSC3、YES3-3B、Ry186和Nl27_(1164),对国内外103个马铃薯品种(系)基于PCR检测,从而追踪目标基因,在育种中实现分子标记辅助选择。结果显示103份材料中,均含有1个或1个以上的抗性标记。只含1个抗性标记的品种(系)共有17个,占供试材料的16.50%;同时含2个抗性标记的品种(系)共有31个,占供试材料的30.10%;同时含3个抗性标记的品种(系)共有34个,占供试材料的33.01%;同时含4个抗性标记的品种(系)共有16个,占供试材料的15.53%;同时含5个抗性标记的品种(系)共有5个,占供试材料的4.85%,分别为‘冀张薯8号’、‘鄂薯10号’、‘黑金刚’、‘中薯18号’、‘维雷巴耶夫’,这5个品种均为目前生产上推广的优良品种。检测结果可以为新品种(系)的推广应用以及抗病毒育种选育提供科学依据,在育种中结合农艺性状评价将筛选出来含多个不同抗性标记的材料作为骨干亲本用于进行聚合育种,在F_1代实生苗阶段进行分子标记检测,结合田间表现,创造出多抗病毒材料。     

小麦3个抗白粉病基因聚合于推广品种后代抗性的遗传分析

为了明确不同抗小麦白粉病基因聚合于推广品种后代的抗性表现,通过复合杂交,将抗小麦白粉病基因Pm4b,Pm13,Pm21聚合并转入推广品种,其后代(F1,F2)进行人工接种和表型抗病调查.结果表明,F1中凡是含有抗白粉病基因之一的材料均表现高抗或免疫.F2中Pm4b,Pm13和Pm21抗病基因聚合的抗病株占的比例最大(71.82%),Pm13和Pm21,Pm4b和Pm21聚合的抗病株占的比例次之(66.67%,64.14%),Pm4b和Pml3抗性基因聚合的抗病株占的比例较小(63.93%).2个抗病基因聚合体中含有Pm21基因的抗性最好.     

中国部分水稻品种Bsr-d1启动子稻瘟病持久抗性位点序列分析

为发掘稻瘟病种质资源持久抗性基因Bsr-d1,本研究对来源中国的210份稻种Bsr-d1基因启动子功能片段511个碱基序列进行了比对分析。结果发现品种间存在18个变异位点28个碱基的差异,根据差异所有品种可归为7种单倍型,其中H4和H6为优势单倍型,分别占测试品种70.48%和23.81%;云南地方品种拥有H1、H2、H3、H4、H5、H6等6种单倍型,优势单倍型为H4 (51.95%)、H6 (35.06%);选育品种有3种单倍型,分别为H4、H6、H7、H6为优势单倍型,地方品种单倍型较选育品种丰富。其他地区品种仅发现H4(1.52%)和H6 (98.48%) 2种单倍型,云南省单倍型更为多样丰富。7种单倍型中仅H1单倍型(占1.43%)携带抗性位点,仅3个云南地方品种出现该单倍型,说明中国地方品种和选育品种中均缺乏Bsr-d1稻瘟病持久抗性基因。本研究结果为寻找和发掘持久抗稻瘟病基因Bsr-d1提供了线索。     

大豆对大豆花叶病毒抗侵染与抗扩展育种应用的讨论

大豆既可抗SMV的侵染,又可抗扩展。抗侵染由一或两对基因控制,具有明显的株系专化性,存在因株系变化而丧失抗性的可能,但抗侵染品种不受SMV的影响,且抗性基因鉴定、转育方便,在品种更替速度不断加快以及注意SMV动态变化的情况下,针对主要流行株系的抗侵染已被广泛利用并将继续发挥重要作用。抗扩展由一对加性主基因和加性-显性多基因共同控制,以主基因作用为主,多基因起修饰作用。这种抗性虽不能抵抗SMV的侵染,但大豆感染后病情较轻,产量损失一般在5%以下,且抗谱广、抗性稳定,抗源丰富。因此,对抗扩展育种应予以重视。随着分子标记辅助选择技术的发展,期望能通过分子标记辅助抗性选择,把对多个株系的抗侵染基因聚合到同一品种,甚至把两类抗性聚合到同一大豆品种。     

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.     

A new rice gall midge resistance gene in the breeding line CR57-MR1523, mapping with flanking markers and development of NILs

Gall midge is the third most destructive insect pests of rice after stem borers and planthoppers. Host plant resistance has been recognized as the most effective and economic, means for gall midge management. With the characterization of a new gall midge biotype (GMB) 4M, unique feature of gall midge resistance in the breeding line CR57-MR1523 was highlighted. Multi-location evaluation of F₃ families derived from the cross TN1 × CR57-MR1523 against different gall midge biotypes helped to identify a new dominant gene conferring resistance against GMB4. This gene has been designated as Gm11t. Though CR57-MR1523 has been extensively used in breeding gall midge resistant rice varieties like Suraksha, neither the genetics of resistance nor chromosomal location of the resistance gene(s) is known. In the present study we have tagged and mapped the new gall midge resistance gene, Gm11t, on chromosome 12, using SSR markers. To map the gene locus, 466 F₁₀ generation Recurrent Inbred Lines (RILs), from the cross of TN1 × CR57-MR1523 were used. Of the 471 SSR markers spread across the rice genome, 56 markers showed polymorphism and were used to screen a subset of the mapping population consisting of 10 resistant (R) and 10 susceptible (S) F₁₀ RILs. Six SSR markers, RM28706, RM235, RM17, RM28784, RM28574 and RM28564 on chromosome 12 were initially found to be associated with resistance and susceptibility. Based on the linkage analysis in selected 158 RILs, we were able to map the locus between two flanking SSR markers, RM28574 and RM28706, on chromosome 12 within 4.4 and 3.8 cM, respectively. Further, two NILs with 99% genetic similarity, were identified from the RILs which differed in gall midge resistance. The tightly linked flanking SSR markers will facilitate marker-assisted gene pyramiding and map-based cloning of the resistant gene. NILs would be valuable materials for functional analysis of the identified candidate gene.     

药用菊花对菊花瘿蚊的抗性研究

以单株虫瘿量作为指标就我国常见的14种药用菊花对菊花瘿蚊的抗性进行鉴定,结果表明,祁菊为高感品种;怀小白菊、小亳菊为感虫品种;温茶菊、杭菊、大亳菊、贡黄菊为抗虫品种;贡白菊及3种野菊花等为高抗品种。抗性机制研究表明,菊花瘿蚊对不同菊花资源的产卵存在选择性差异。各菊花品种瘿蚊蛹重差异不大,但死亡率差异较大,存在抗生性差异。     

Genetic analysis and pyramiding of two gall midge resistance genes (Gm-2 and Gm-6t) in rice ( Oryza sativa L.)

Asian rice gall midge (Orseolia oryzae) is a major pest across much of south and southeast Asia. This pest is genetically diverse and many gall midge biotypes are known to exist in each country. During the last three decades, host plant resistance has proved to be the most effective mechanism of controlling the Asian rice gall midge. Seven genes conditioning resistance to gall midge larvae have been identified in rice (Oryza sativa) and are being used in cultivar improvement programs. However, some of these genes are rendered ineffective by new gall midge biotypes. Increased understanding of genetics, inheritance, allelic relationships and linkage is necessary to maximise the durability of major gene resistance by the pyramiding of these genes. The two genes, Gm-2 and Gm-6(t), are known to confer resistance against a number of biotypes in India and China, respectively. An F₃ population derived from a cross between Duokang #1 (donor of Gm-6(t)) and Phalguna (donor of Gm-2) was screened against Chinese gall midge biotype 4 at Guangdong, China, and Indian gall midge biotype 1 at Raipur, India. At each location, separately,a single gene governed resistance. The parallel segregation of 417 F₃progenies for both biotypes at two locations revealed that recombination had occurred between the two genes, establishing that the two genes are not allelic. However, the two genes Gm-2 and Gm-6(t), were found to be linked with a distance of ∼16.3 cM. A number of lines homozygous at one locus and segregating for the other locus were identified and selected. These lines were selfed to obtain lines homozygous for the favourable alleles at both loci (two locus pyramids). This is the first report on use of conventional host-pest interaction method for pyramiding two closely located Gm-resistance loci of dissimilar effects. The implications of deployment of these pyramids within and across country borders, with reference to the prevailing gall midge populations are discussed. This revised version was published online in August 2006 with corrections to the Cover Date.     

Molecurar Breeding for Resistant Varieties Against Asian Rice Gall Midge in China

Asian rice gall midge （GM） is a major rice pest in South China. Breeding resistance varieties has been a viable and ecologically acceptable approach for managing the pest. This paper reports that the progress of breeding resistant varieties using the markers linked to Gin6 against GM fxom the year 1998 to 2006 in China. The DNA fingerprints of 4 biotypes of GM population fxom 7 locations were analyses by AFLP. Base on the fine mapping of resistance gene Gin6 against all 4 Chinese GM biotypes by RAPD and SSR methods respectively, the STS markers and SSR markers linked to gene Gin6 were used for breeding through MAS. Some new resistant garplasm with Gin6 gene were created. And six cultivars and six two-line or one line three-line hybrid rice against GM were bred and extended to the farmer. The technique system of MAS for resistant varieties against Asian rice gall midge was set up at Guangdong province of China.     

Flanking SSR markers for allelism test for the Asian rice gall midge (Orseolia oryzae) resistance genes

Screening of rice germplasm against Asian rice gall midge, Orseolia oryzae (Wood-Mason), biotypes in India has led to identification of over 300 resistant rice genotypes. However, only ten resistance genes have been characterized so far. Identification of new genes through classical allelism test is tedious and time consuming. We propose to use closely linked flanking Simple Sequence Repeat (SSR) markers in allelism tests for identification of resistance genes. Of the ten known gall midge resistance genes, eight have been tagged and mapped. The Gm1 and Gm2 genes have closely linked flanking markers. Hence SSR markers RM219 and RM444, flanking the gene Gm1, and RM317, RM241 along with the SCAR marker F8, flanking the gene Gm2, were selected for this study. Tests with one set of 13 genotypes likely to carry Gm1 and another set of 17 genotypes suspected to contain Gm2 suggested the presence of the respective allele in all the 13 and 15 genotypes from these sets, respectively. Classical allelism test perfectly matched with the markers test. There were two exceptions involving amplification with RM444 in cultivar Kavya and with RM241 in genotype AE20, suggesting a single recombination which could have resulted in the mismatch. All the three markers in the genotype Bhumansan and the two flanking markers RM317 and F8 in AE20 indicated the absence of the Gm2 allele. This was validated through a classical test, revealing a segregation ratio of 15 resistant: 1 susceptible F₂ progeny of both the crosses between the Gm2 source Phalguna and these genotypes. We performed the allelism test with the markers on another set of 56 randomly selected gall midge resistant genotypes to discover possible sources of new resistance genes.     

Mapping and marker-assisted breeding of a gene allelic to the major Asian rice gall midge resistance gene <Emphasis Type="Italic">Gm8</Emphasis>

Host plant resistance is the preferred management strategy for Asian rice gall midge (Orseolia oryzae), a serious pest in many rice-growing countries. Identification of simple sequence repeat (SSR) markers that are tightly linked to pest resistance genes can accelerate development of gene pyramids for durable/multiple resistance. Based on conventional and molecular allelism tests, we report herein that rice genotype Aganni possesses Gm8 gene, conferring hypersensitive independent (HR– type) resistance to gall midge biotypes GMB1, GMB2, GMB3, GMB4, and GMB4M. The gene Gm8 was mapped to chromosome 8 within a 400-kbp region, and the SSR markers RM22685 and RM22709 flank the gene closely. Using these closely linked flanking markers, nine other gall midge-resistant genotypes were identified as carrying the same gene Gm8. Through marker-assisted selection, Gm8 has been introgressed into an elite bacterial blight-resistant cultivar, Improved Samba-Mahsuri (IS).     

Variation in inheritance of resistance to sorghum midge, Stenodiplosis sorghicola across locations in India and Kenya

Sorghum midge [Stenodiplosis sorghicola (Coquillett)] is an important pest of grain sorghum, and host plant resistance is one of the important components for the management of this pest. We studied the inheritance of resistance to this insect involving a diverse array of midge-resistant and midge-susceptible genotypes in India and Kenya. Testers IS 15107, TAM 2566, and DJ 6514, which were highly resistant to sorghum midge in India, showed a greater susceptibility to this insect in Kenya. The maintainer lines ICSB 88019 and ICSB 88020 were highly resistant to sorghum midge in India, but showed a susceptible reaction in Kenya; while ICSB 42 was susceptible at both the locations. General combining ability (GCA) effects for susceptibility to sorghum midge for ICSA 88019 and ICSA 88020 were significant and negative in India, but such effects were non-significant in Kenya. The GCA effects of ICSB 42 for susceptibility to sorghum midge were significant and positive at both the locations. The GCA effects were significant and positive for Swarna, and such effects for IS 15107 and TAM 2566 were negative at both the locations. GCA effect of DJ 6514 were significant and negative in India, but non-significant and positive in Kenya; while those of AF 28 were significant and positive during the 1994 season in India, but significant and negative in Kenya. Inheritance of resistance to sorghum midge is largely governed by additive type of gene action. Testers showing resistance to sorghum midge in India and/or Kenya did not combine with ICSA 88019 and ICSA 88020 to produce midge-resistant hybrids in Kenya. Therefore, it is essential to transfer location specific resistance into both parents to produce midge-resistant hybrids.     

Inheritance of resistance to wheat midge, Sitodiplosis mosellana, in spring wheat

Inheritance of resistance to a wheat midge, Sitodiplosis mosellana (Géhin), was investigated in spring wheats derived from nine resistant winter wheat cultivars. F₁ hybrids were obtained from crosses between resistant winter wheats and susceptible spring wheats, and used to generate doubled haploid populations. These populations segregated in a ratio of 1:1 resistant to susceptible, indicating that a single gene confers the resistance. The F₂ progeny from an intercross among spring wheats derived from the nine resistance sources did not segregate for resistance. Therefore, the same gene confers resistance in all nine sources of resistance, although other genes probably affect expression because the level of resistance varied among lines. Heterozygous plants from five crosses between diverse susceptible and resistant spring wheat parents all showed intermediate levels of response, indicating that resistance is partly dominant. Susceptible plants were reliably discriminated from heterozygous or homozygous resistant ones in laboratory tests, based on the survival and development of wheat midge larvae on one or two spikes. This powerful resistance gene, designated Sm1, is simply inherited and can be incorporated readily into breeding programmes for spring or winter wheat. However, the use of this gene by itself may lead to the evolution of a virulent population, once a resistant cultivar is widely grown.     

Compensation in grain weight and volume in sorghum is associated with expression of resistance to sorghum midge, Stenodiplosis sorghicola

Sorghum midge, Stenodiplosis sorghicola (Coquillett) is one of the most important pests of grain sorghum worldwide. We studied the inheritance of resistance to sorghum midge and compensation in grain weight and volume in panicles of sorghum hybrids and their parents under uniform infestation (40 midges per panicle for two consecutive days). Sorghum midge damage ranged from 8.2 to 82.4% in the maintainer lines (B-lines) of the females parents (A-lines), and 9.0 to 67% in the male parents (restorer lines). Hybrids involving resistant × resistant parents were highly resistant, while those involving resistant ×susceptible and susceptible × resistant parents showed moderate susceptibility. Susceptible × susceptible hybrids were susceptible. Compensation in (percentage increase) grain weight and volume in midge-infested panicles of midge-resistant parents and their F₁ hybrids was greater than in midge-susceptible parents and hybrids. General combining ability effects for midge damage, and grain weight and volume were significant and negative for the midge-resistant females (ICSA 88019 and ICSA 88020), whereas those for the midge-susceptible females (ICSA 42 and 296A) were significant and positive. However, the reverse was true in case of compensation in grain weight and volume. Inheritance of compensation in grain weight and volume and resistance to sorghum midge is controlled by quantitative gene action with some cytoplasmic effects. Resistance is needed in both parents to realize full potential of midge-resistant hybrids. This revised version was published online in July 2006 with corrections to the Cover Date.