Identification and molecular tagging of two Arabidopsis resistance genes to Botrytis cinerea

To map Arabidopsis resistance genes to Botrytis cinerea, Arabidopsis Col-0 ecotype resistant to B. cinerea BC18 isolate and Arabidopsis Ler ecotype susceptible to B. cinerea BC18 isolate were crossed. According to the resistant responses of the F₁, BC₁ and F₂ populations to B. cinerea, we identified two genes, named BC1 and BC2, responsible for the resistance of Arabidopsis Ler ecotype to B. cinerea. Through the method of map-based cloning, BC1 was linked to DNA markers CCR1 and DHS1 on the fourth chromosome of Arabidopsis with genetic distances of 1.2 cM and 1.6 cM for CCR1 and DHS1, respectively, and BC2 was linked to DNA markers CA72/NGA151 and NGA106 on the fifth chromosome with genetic distances of 1.4 cM and 2.4 cM for CA72/NGA151 and NGA106, respectively. Our results are beneficial for chromosome walking so that we can obtain the whole gene sequences, which will facilitate the understanding of their roles and manners of resistance to B. cinerea.     

Molecular Mapping of Two Novel Stripe Rust Resistant Genes YrTp1 and YrTp2 in A-3 Derived from Triticum aestivum × Thinopyrum ponticum

Loss of variety resistance to stripe rust (Puccinia striiformis Westend f. sp.tritici) is an important factor causing massive periodical epidemic of rust in wheat production. Creation and development of new races of rust pathogen have led to serious crisis of resistance loss in widely planted varieties. This has quickened the search for new resistance resources. Molecular marker could facilitate the identification of the location of novel genes. A line A-3 with high resistance (immune) to currently epidemic yellow rust races (CY29, 31, 32) was screened out in offspring of Triticum aestivum × Thinopyrum ponticum. Segregation in F₂ and BC₁ populations indicated that the resistance was controlled by two independent genes: one dominant and one recessive. SSR markers were employed to map the two resistant genes in the F₂ and BC₁ populations. A marker WMC477-_167bp located on 2BS was linked to the dominant gene with genetic distance of 0.4 cM. Another marker WMC364-_{208 bp} located on 7BS was linked to the recessive-resistant gene with genetic distance of 5.8 cM. The two genes identified in this paper might be two novel stripe rust resistant genes, which were temporarily designated as YrTp1 and YrTp2, respectively. The tightly linking markers facilitate transfer of the two resistant genes into the new varieties to control epidemic of yellow rust.     

黄瓜耐冷性遗传分析与连锁标记筛选

黄瓜(Cucumis sativusL.)是典型的冷敏型植物。对黄瓜来说,冷害是生产上制约其丰产、优质的主要逆境因素之一。为了掌握黄瓜耐冷性遗传规律,加快黄瓜耐冷品种的选育,本研究选取黄瓜耐冷型品系0839和低温敏感型品系B52为亲本杂交得到F1和F2,进行苗期低温鉴定和遗传分析。供试亲本的耐冷性主要受一对显性单基因控制。结合BSA(群体分离分析)和SSR分子标记,获得了与黄瓜耐冷性主效基因连锁的SSR标记。通过F2群体分析,鉴定出与耐冷性基因连锁的分子标记SSR07248,该标记与耐冷性基因间的遗传距离为32.6cM。     

Resistance to the Whitefly Aleurotrachelus socialis (Hemiptera: Aleyrodidae) and SSR Marker Identification in Advanced Populations of the Hybrid Manihot esculenta subsp. Manihot flabellifolia

Genes resistant to Aleurotrachelus socialis were transferred to the F₁ from the interspecific hybrid wild species of Manihot flabellifolia to M. esculenta and two advanced generations of backcrosses (BC₁ and BC₂). We characterized the resistance of A. socialis transferred to BC₂ parents (CW67-160, CW67-130, CW67-44), MTAI-8 (BC₁), resistant (CMB9B-73) and susceptible (CMB9B-104) genotypes from contrasting pools, and resistant (MEcu-72) and susceptible (CMC-40) genotypes. Whitefly demography and biology were evaluated. SSR molecular markers associated with a phenotypic response of plant resistance were detected in segregating populations (BC₂). Results showed that although female survival time was similar on all hosts, the lowest averages of longevity, fecundity and oviposition rate were observed in the resistant control MEcu-72, only being significantly similar to the parent CW67-130. When the BC₁ and BC₂ populations were compared, it was found that A. socialis fecundity was eight times lower on CMB9B-73 progeny than on CW67-130, expressing the highest levels of resistance to the whitefly. Ten genotypes of CMB9A and CMB9B family had the best segregation. A total of 486 microsatellite primers were evaluated using bulked segregant analysis (BSA), 11 showed polymorphism between the contrasting pools and only one showed significant differences between resistant and susceptible individuals. In conclusion, fecundity was the parameter that impacted most on the intrinsic rate of A. socialis population growth.     

Identification of a Resistance Gene bls1 to Bacterial Leaf Streak in Wild Rice Oryza rufipogon Griff.

Bacterial leaf streak (BLS) of rice, caused by Xanthomonas oryzae pv. oryzicola (Xoc) is a worldwide destructive disease. Development of resistant varieties is considered to be one of the most effective and eco-friendly ways to control the disease. However, only a few genes/QTLs having resistance to BLS have been identified in rice until now. In the present study, we have identified and primarily mapped a BLS-resistance gene, bls1, from a rice line DP3, derived from the wild rice species Oryza rufipogon Griff. A BC₂F₂ (9311/DP3//9311) population was constructed to map BLS-resistance gene in the rice line DP3. The segregation of the resistant and susceptible plants in BC₂F₂ in 1:3 ratio (χ²=0.009, χ²_{0.05, 1}=3.84, P>0.05), suggested that a recessive gene confers BLS resistance in DP3. In bulked segregant analysis (BSA), two SSR markers RM8116 and RM584 were identified to be polymorphic in resistant and susceptible DNA bulks. For further mapping the resistance gene, six polymorphic markers around the target region were applied to analyze the genotypes of the BC₂F₂ individuals. As a result, the BLS-resistant gene, designated as bls1, was mapped in a 4.0-cM region flanked by RM587 and RM510 on chromosome 6.     

Inheritance and molecular markers for the seed coat color in Brassica juncea

To elucidate the inheritance of seed coat color in Brassica juncea, Sichuan Yellow inbred (PY) was crossed with the Ziyejie inbred, and their F₁, F₂ and BC₁ and BC₂ progenies, derived from backcrossing to PY, were phenotyped for seed coat color. Results showed that the yellow seed coat was controlled by two independent recessive loci. Seven brown-seeded near-isogenic lines were developed by successive backcrosses to PY and by selfing. One of the BC₆F₂ populations segregated for a single locus controlling seed coat color was used for mapping. Using the 88 primer pairs from sequence-related amplified polymorphism and the 500 random primers, two markers were found to be linked to the gene for brown seed coat, which were designated as SCM57 and SCM1078. The crossover between these markers and the brown seed coat loci was 2.35% and 7.06%, respectively. A sequence characterized amplified region (SCAR) marker according to Negi et al. (2000), designated as SZ1-331, was found to be linked to the gene for brown seed coat, with a crossover estimate of 2.35%. The markers were located on the same side of the brown seed coat loci and 2.41, 7.51 and 2.41 cM away from the brown seed coat locus. The seven brown-seeded near-isogenic lines were classified into two groups by three DNA markers. They were located at the same linkage group of the marker RA2-A11 previously published by Padmaja et al. (2005).     

Identification of the resistance gene to powdery mildew in Chinese wheat landrace Baiyouyantiao

Powdery mildew, caused by Blumeria graminis f. sp. tritici (Bgt), is one of the most damaging diseases to wheat in the world. The cultivation of resistant varieties of wheat is essential for controlling the powdery mildew epidemic. Wheat landraces are important resources of resistance to many diseases. Mapping powdery mildew resistance genes from wheat landraces will promote the development of new varieties with disease resistance. The Chinese wheat landrace Baiyouyantiao possesses characteristic of disease resistance to powdery mildew. To identify the resistance gene in this landrace, Baiyouyantiao was crossed with the susceptible cultivar Jingshuang 16 and seedlings of parents and F₁, BC₁, F₂, and F_2:3 were tested with Bgt isolate E09. The genetic results showed that the resistance of Baiyouyantiao to E09 was controlled by a single recessive gene, tentatively designated PmBYYT. An Illumina wheat 90K single-nucleotide polymorphism (SNP) array was applied to screen polymorphisms between F₂-resistant and F₂-susceptible DNA bulks for identifying the chromosomal location of PmBYYT. A high percentage of polymorphic SNPs between the resistant and susceptible DNA bulks was found on chromosome 7B, indicating that PmBYYT may be located on this chromosome. A genetic linkage map of PmBYYT consisting of two simple sequence repeat markers and eight SNP markers was developed. The two flanking markers were SNP markers W7BL-8 and W7BL-15, with genetic distances of 3 and 2.9 cM, respectively. The results of this study demonstrated the rapid characterization of a wheat disease resistance gene and SNP marker development using the 90K SNP assay. The flanking markers of gene PmBYYT will benefit marker-assisted selection (MAS) and map-based cloning in breeding wheat cultivars with powdery mildew resistance.     

中梁12小麦抗条锈病基因遗传分析与SSR分子定位

中梁12具有抗逆性强、适应性广、抗条锈性强等许多优良的生物学特性。为明确其抗条锈性及遗传规律,利用当前流行的中国条锈菌小种CYR30对抗病品种中梁12与感病品种铭贤169及其杂交后代代F1、F2、F3和BC1代进行苗期抗条锈性遗传分析,并对其抗条锈基因进行SSR分子标记。结果表明,中梁12对CYR30小种具有良好的抗性,由1对显性基因控制,暂命名为YrZh12。该基因与位于小麦7AL染色体上的4个SSR位点Xwmc695、Xcfd20、Xbarc121和Xbarc49连锁,其中最近的侧翼位点为Xcfd20和Xbarc121,其遗传距离分别是3.1cM和4.9cM。系谱分析YrZh12基因可能来自抗引655,由于7AL染色体上没有其他抗条锈病基因,YrZh12可能是一个抗条锈病的新基因。     

我国小麦农家品种白老芒麦的抗条锈性遗传分析

以感病材料铭贤169作母本,白老芒麦作父本配制杂交组合,获得杂种F1代种子;F1代植株自交获得F2代种子,以F1代作为父本与铭贤169回交获得BC1代种子。对亲本、F1代、F2代和BC1代植株接种鉴定,根据F1代、BC1代的抗性表现和F2代的抗感分离情况推知白老芒麦(甘地806)对CYSu-XI的抗病性是由一对显性基因和两对隐性基因的互补作用控制。     

小麦抗白粉病基因SRAP标记的鉴定及序列分析

利用240对SRAP引物组合,扩增普通小麦SF42(高感白粉病)和ZB90(对白粉病免疫)。40%的引物组合能在感抗材料中扩增出稳定的多态性条带。进一步用这些引物分析SF42×ZB90的F2分离群体,发现有4对引物组合Me5+Em5,Me8+Em7,Me8+Em16,Me12+Em7扩出的5个SRAP标记与小麦品种ZB90所含的抗白粉病基因连锁。对这些标记进行回收、克隆、测序。序列分析发现,这些标记均含有ORF,并且有4个标记含有信号肽和跨膜区等保守结构域。     

Inheritance of Resistance to SMV3 and Identification of RAPD Marker Linked to the Resistant Gene in Soybean

One SMV resistant soybean line (95-5383) was crossed with four susceptible soybean varieties/line ( HB1, Tiefeng21, Amsoy, Williams) and one resistant introduced line PI486355. Their F1 and F2individuals were identified for SMV resistance by inoculation with SMV3. The results showed that in the four crosses of resistant × susceptible, F1 were susceptible and the ratio of F2 populations was 1 resistant : 3susceptible (mosaic and necrosis), indicating that 95-5383 carries one recessive gene that confer resistance to SMV3. There is segregation of susceptibility in F2 progenies from the cross of 95-5383 × PI486355, indicating that the SMV3 resistant gene in 95-5383 is located at different locus from PI486355. By bulked segregating analysis (BSA) in F2 populations of 95-5383 × HB1, one codominant RAPD marker OPN11980/1070 closely linked to SMV3 resistance gene amplified with RAPD primer OPN11 was identified. The DNA fragment OPN11980 was amplified in resistant parent 95-5383 and resistant bulk, and OPN111070 was amplified in susceptible parent HB1 and susceptible bulk. OPN11980/1070 was amplified in F1. Identification of the markers in F2 plants showed that the codominant marker OPN11980/1070 is closely linked to the SMV resistance locus in95-5383, with genetic distance of 2.1cM.     

Fine mapping and genetic analysis of resistance genes,Rsc18, against soybean mosaic virus

Soybean mosaic virus (SMV) affects seed quality and production of soybean (Glycine max (L.) Merr.) worldwide. SC18 is one of the dominant SMV strains in South China, and accession Zhonghuang 24 displayed resistance to SC18. The F₁, F₂ and 168 F₁₁ recombinant inbred lines (RILs) population derived from a hybridization between Zhonghuang 24 (resistant, R) and Huaxia 3 (susceptible, S) were used in this study. According to the segregation ratios of the F₂ generation (3R:1S) and the recombinant inbred lines (RILs) population (1R:1S), one dominant locus may regulate the resistance to SC18 in Zhonghuang 24. By using composite interval mapping (CIM), Rsc18 was mapped to a 415.357-kb region on chromosome 13. Three candidate genes, including one NBS-LRR type gene and two serine/threonine protein type genes, were identified according to the genetic annotations, which may be related to the resistance to SC18. The qRT-PCR demonstrated that these genes were up-regulated in the R genotype compared to the control. In conclusion, the findings of this research enhanced the understanding about the R genes at the Rsc18 locus. Moreover, our results will provide insights for designing molecular markers to improve marker-assisted selection and developing new varieties with resistance to SC18.     

小麦品种辽春10抗叶锈病基因LrLC10的比较基因组学定位

为明确小麦品种辽春10对叶锈菌小种PHT抗病的遗传基础,利用感病小麦材料87-1与抗病小麦材料辽春10构建的F_(2:3)群体,对其进行成株期抗病性鉴定和遗传分析。结果表明,辽春10中含有1个显性抗叶锈病基因,暂命名为LrLC10。利用BSA法和比较基因组学策略对该抗病基因进行分子标记分析,将LrLC10定位于小麦2BS染色体上。共构建了含有8个分子标记的LrLC10基因的连锁图,其中:CAUT253位于LrLC10的远着丝粒侧,距离为0.1cM;CAUT163和CAUT131与LrLC10共分离;CAUT239位于LrLC10的近着丝粒侧,遗传距离为0.5cM。     

利用回交和MAS技术改良优质两系不育系金山s-2的稻瘟病抗性

 以水稻品系5173为抗性供体亲本,通过连续回交和MAS技术将稻瘟病抗性基因Pi-2导入优质低温敏核不育系金山s-2的遗传背景中。在各世代皆利用与Pi-2紧密连锁的SSR标记SRM24对目标基因进行“前景选择”,并结合形态性状进行“背景选择”,直至BC₃F ₂, 获得抗病标记纯合且其它性状与金山s-2非常相似的植株9株。在BC₃F ₁,对中选的4个单株利用SRAP标记进行遗传背景分析表明,它们与受体亲本金山s-2具较高的遗传相似系数;对选育出的株系的温敏不育性特性观察表明,获得的4个近等基因系,它们保持了亲本育性稳定、临界温度低和可繁性好的特性;对BC₃F 1∶2株系抗病鉴定结果表明,通过标记选出的单株均表现抗病,说明利用SRM24对Pi-2基因进行选择是可靠的,能够满足需要。因此,在BC₃F ₁决选出4个单株可望替代不抗病的金山s-2直接应用于生产。     

Characterization and fine mapping of RTMS10, a semi-dominant reverse thermo-sensitive genic male sterile locus in rice

The discovery and application of environment-sensitive genic male sterile (EGMS) rice germplasm provide an easy method for hybrid rice breeding and have made great contributions to hybrid rice production. Typically, the photoperiod- and thermo-sensitive GMS (P/TGMS) lines utilized in two-line hybrid systems are male sterile under long day or/and high temperature but fertile under short day or/and low temperature conditions. However, YannongS (YnS), a reverse TGMS (rTGMS) line, is sterile under low temperature (<29°C) and fertile under high temperature (>29.5°C). Here, we report a genetic study on the rTGMS trait in YnS. Interestingly, the F₁ plants of the cross between YnS and a cultivar, L422, were male sterile at 22°C and completely fertile at 27°C. Moreover, the segregation ratio of fertile and sterile individuals in YnS/L422 F₂ populations changed from 1:3.05 to 2.95:1 when the ambient temperature increased, showing that the rTGMS trait exhibits semi-dominance in YnS. We further found a locus on chromosome 10, termed RTMS10, which controls the rTGMS trait in YnS. We then finely mapped RTMS10 to a ～68 kb interval between markers ID13116 and ID1318 by YnS/L422 BC₆F₂ populations. A near iso-genic line (NIL) NL1 from the BC₆F₃ generation was developed and the pollen of NL1 became abnormal from the meiosis stage under low temperature. In summary, we identified an rTGMS locus, RTMS10, and provided co-segregated markers, which could help to accelerate molecular breeding of rTGMS lines and better understand the rTGMS trait in rice.     

利用大白菜×芜菁F2群体定位抗根肿病QTL及上位性互作分析

【目的】挖掘和分析芸薹种抗根肿病基因及基因间的互作关系,为芸薹种抗根肿病育种提供理论依据。【方法】以大白菜自交系‘BJN’为母本,芜菁自交系‘Siloga’为父本进行杂交获得F₁。F₁单株自交获得由140个单株构成的F₂群体,用于遗传图谱构建。95个F₂单株及其F₃家系用于抗根肿病（CR）性状的QTL定位和上位性互作分析。利用1 214个分子标记和前人开发的与7个CR连锁的22个标记进行亲本间多态性筛选。根据作图群体的多态性标记基因型,采用JoinMap 4.0作图软件构建遗传连锁图谱。以采自甘蓝型油菜栽培地的根肿菌对2个亲本及其95个F_2：3家系进行根肿病抗性鉴定。根据F₃植株的发病等级,计算F₂单株的平均发病指数（DI）。利用Windows QTL Cartographer 2.5软件,采用复合区间作图法检测抗根肿病QTL。利用基于混合线型模型的QTL Network 2.0软件进行互作关系分析。SPSS 18.0.0软件用于分析F₂群体中QTL连锁标记的基因型与其相应个体平均DI值间的相关性。双因素方差分析方法分析QTL连锁标记的交互作用。通过单因素方差分析,采用最小显著差异法和q检验（SNK）多重比较QTL紧密连锁标记（sau_um026和BrID90197)组合成的9种基因型在根肿病抗性上的差异。【结果】抗病性鉴定表明‘Siloga’对根肿菌表现为抗病,而‘BJN’表现为感病。F₂群体中根肿病发病指数呈偏正态分布,表明根肿病抗性表现为由主效基因存在的多基因控制的数量性状。利用检测到的261个多态性标记构建出一个包含222个标记和10条连锁群的芸薹种遗传图谱。该图谱总长度为1 152.6 cM,定位了与3个CR连锁的5个标记,覆盖了大白菜参考基因组的88.6%。通过QTL定位共检测到源于‘Siloga’的2个QTL位点,分别位于A3连锁群的主效QTL（qPbBa3.1）和A8连锁群的微效QTL（qPbBa8.1）。qPbBa3.1和qPbBa8.1的贡献率分别为19.02%和7.82%。qPbBa3.1区域内包含有抗根肿病基因CRa或CRb,而qPbBa8.1与Crr1毗邻。此外,检测到qPbBa3.1和qPbBa8.1间的上位性互作,互作效应为加性×加性,贡献率为6.58%。双因素方差分析表明,sau_um026与BrID90197间存在极显著差异（P=7.22×10^-5）,进一步验证了qPbBa3.1和qPbBa8.1间的互作效应。单因素方差分析表明,sau_um026和BrID90197的9种基因型间存在显著性差异（P=9.45×10^-10）。多重比较结果表明,qPbBa3.1为抗病亲本‘Siloga’基因型的个体抗病性显著高于其他基因型,杂合基因型的高于感病亲本‘BJN’基因型,含有qPbBa8.1的个体抗病性得到加强。【结论】芜菁自交系‘Siloga’根肿病抗性受主效qPbBa3.1,微效qPbBa8.1,qPbBa3.1和qPbBa8.1间的加性×加性上位性互作效应的影响。     

Breeding of CMS maintainer lines through anther culture assisted by high-resolution melting-based markers

The integrated use of molecular marker-assisted selection (MAS) and anther culture has potential to significantly increase efficiency in plant breeding; however, reports on this kind of practical use are very limited. In the present study, we report the development of cytoplasmic male sterile (CMS) maintainers with aroma, disease resistance and red-brown hulls, as an example of integration of MAS and anther culture in rice breeding. A high-resolution melting (HRM)-based functional molecular marker was developed for the red-brown hull trait caused by a unique mutation (rbh1) in OsCAD2. Functional molecular markers for genes of rice blast resistance (Pi2), aroma (fgr) and red-brown hull (rbh1) were used for precise genotyping of individual plants in the BC₁ and BC₂F₂ populations derived from a cross between CMS maintainers Huaxiang B (pi2–/rbh1–/fgr–) and Rong 3B (Pi2+/RBH1+/Fgr+). A total of 89 doubled haploid (DH) lines were generated from selected BC₂F₂ plants (Pi2+/rbh1–/fgr–) by anther culture. Seven DH lines were subsequently selected as the potential new CMS maintainers based on their overall performance and high resistance to blast. Our study demonstrated that integration of MAS and anther culture significantly accelerated the development of CMS maintainers with multiple stacked genes.     

分子连锁分析探讨家蚕高抗BmNPV品系的抗性遗传基础

【目的】家蚕核型多角体病毒(Bombyx mori nucleopolyhedrovirus,BmNPV)所引发的血液型脓病是一种传染性强的蚕病,极大地影响蚕业生产。本研究旨在定位对BmNPV高抗的家蚕品系中控制其抗性的基因,进而解析其抗性遗传机制,为培育抗性素材和品系提供理论支持。【方法】以BmNPV高抗家蚕品系99R和较感品系Dazao-N为亲本,配制连锁分析(BC_1F)和定位分析(BC_1M)回交群体。首先对两个亲本品系进行浓度梯度添毒,统计感病死亡的家蚕头数,运用SPSS 17.0软件,计算其半致死剂量(LD_(50)),在此基础上确定BC_1分离群体的攻毒剂量,并通过单头定量攻毒,选取感病个体作为连锁定位分析材料;利用筛选得到的覆盖家蚕全套常染色体的多态性标记进行分型,并通过T检验计算各标记与抗性的连锁显著性水平(P值),筛选出与抗性相连锁的标记。在这些标记所在的染色体上加密标记,检测各标记在定位分析群体中的基因型,定位抗性基因。【结果】LD_(50)(99R)=2.92×10~6个多角体/头,LD_(50)(Dazao-N)=9.78×10~5个多角体/头,基于双亲的半致死剂量,选择介于两者之间且略高于其均值的剂量——2×10~6个多角体/头作为BC_1分离群体的攻毒剂量;先后于2014年秋季和2015年春季处理并检测连锁分析群体,前后两次所进行的连锁分析结果有较大差异,其中第一次找到Chr22上的多态性标记S2205与99R抗性连锁,而第二次的连锁分析显示标记S2205与抗性不连锁,也没有找到其他的连锁关系。通过与前人对BmNPV抗性的连锁定位分析结果进行对比,发现连锁定位分析结果的不可重复性是一个普遍的问题。AY380833是GenBank中已公布的在家蚕高抗品系NB和871C中与其抗性位点紧密连锁的分子标记,本研究调查发现其与99R和871C的抗性位点均不连锁。【结论】分子连锁分析结果证明,家蚕对BmNPV的抗性在不同抗性品系中遗传基础有很大的差异性,同一品系可能具有多个抗性位点;家蚕对BmNPV的抗性是一种复杂性状,在符合"质量-数量性状"结论的同时,其数量性状特征突出。     

一个水稻落粒性基因SH1的SSR标记定位

 以籼稻品种93-11为轮回亲本,与粳稻品种日本晴杂交并回交的高世代分离群体为研究材料,选用104个多态性的SSR标记对水稻的落粒性基因进行定位。结果表明,在BC₄F₂群体中,6个标记的基因型来自于日本晴;在BC₄F₃定位群体中,难落粒植株数与易落粒植株数的分离比例为3:1,落粒性受1对显性基因控制,命名为SH1;分子标记与落粒性共分离分析将SH1定位在SSR标记RM5389和RM1068、RM1387之间,与3个标记的遗传距离分别为0.7cM、5.5cM和13.1cM,此结果为该基因的分子标记辅助选择奠定了基础。     

Heredity Analysis and Gene Mapping of Bruchid Resistance of a Mungbean Cultivar V2709

Bruchid is a serious insect pest of mungbean [Vigna radiata （L.） Wilczek] and can inflict serious loss. A resistant variety from India, V2709, was crossed with a susceptible variety, Zhonglti 1, from the World Vegetable Center, Asian Vegetable Research and Development Center （AVRDC）. Segregation of the F2, BC1F1, and F3 populations showed that bruchid resistance of V2709 is controlled by a single dominant locus. To find molecular marker linked with the resistant locus, 63 randomly amplified polymorphic DNA markers and 113 sets of SSR/STS primers were used in a bulked segregant analysis. Two of the markers, OPC-06 and STSbr2, were found to be linked with the locus （named as Br2）. Further analysis suggested that the genetic distances between these two markers and Br2 were 11.0 and 5.8 cM, respectively.