Identification of QTLs Related to Bolting in Brassica rapa ssp. pekinensis （syn. Brassica campestris ssp. pekinensis）

A genetic linkage map of Brassica rapa ssp. pekinensis was constructed with 186 AFLP （amplified fragment length polymorphism） markers by using a doubled-haploid （DH） population with 183 individuals. The individuals were derived from F1 which was developed by crossing a bolting resistant DH line Y-177-12 and an easy bolting DH line Y195-93a. AFLPs were generated by the use of restriction enzymes EcoR Ⅰ and Mse Ⅰ . The segregation of each marker and linkage was analyzed by using JoinMap version 3.0. Mapped markers were aligned in ten linkage groups which covered 887.8 cM with an average marker interval of 4.47 cM. Markers showing skewed segregation ratio were clustered in six LGs. Quantitative trait loci （QTL） were mapped for bolting resistance by using MAPQTL 4.0 package. Four QTLs explaining from 7.0 to 9.4% of the total variation were detected, all of them increase bolting resistance. These mapped QTLs could be used to develop a marker assisted selection programme for bolting resistance breeding.     

大白菜小孢子胚诱导和植株再生

研究大白菜游离小孢子胚诱导主要影响因素,旨在优化培养体系,创制优异DH群体,获得纯合育种材料。以15个大白菜杂交种为试材,采用游离小孢子培养方法,研究了基因型、培养基成分、低温预处理、取材时期对小孢子胚发生的影响。结果表明:不同试材的小孢子胚发生频率有明显差异,有13个品种诱导得到了胚状体,最高出胚率达每蕾10.16胚;NLN培养基中添加0.05～0.20mg.L-1的6-BA和0.10mg.L-1NAA对胚状体的发生和发育有促进作用;花蕾低温预处理对胚状体发生有明显促进作用;盛花期取样的小孢子产胚率高于始花期和末花期;改良MS培养基中添加0.10g.L-1的活性炭,有利于胚状体的发育及成苗;MS 0.10mg.L-1NAA为小孢子植株生根最适宜的培养基;建立了高效的大白菜游离小孢子培养与植株再生体系。     

大白菜中与芜菁花叶病毒(TuMV)感病基因连锁的AFLP标记

 TuMV是大白菜病毒病的主要病原物之一,所以抗TuMV病毒病成为白菜抗病育种的主要目标,寻找与抗性基因紧密连锁的分子标记,进行分子标记辅助育种,是提高白菜抗病育种效率的有效手段。以抗病自交系Brp0058和感病自交系Brp0181杂交后代的F2分离群体为试材,采用分离群体分组分析法(BSA),筛选到2个与TuMV感病基因紧密连锁的AFLP分子标记,利用MAPMAKER/EXP(Version3.0)作图软件统计,其遗传距离分别为7.5和8.4cM。     

Identification of Heat Tolerance Linked Molecular Markers of Chinese Cabbage (Brassica campestris L.ssp. pekinensis)

Genetically stable population of recombination inbred line (RIL) was derived from a cross between a heat tolerant line 177 and a heat sensitive line 276 of Chinese cabbage (Brassica campestris L. ssp.pekinensis ) by single seed descent. The RILs were analyzed using isozyme, RAPD and AFLP techniques in order to find molecular markers that are linked to heat tolerance quantitative trait loci (QTL). The results of variance analysis of single factor indicated that there were 9 molecular markers closely linked with heat tolerance QTL, including 5 AFLP markers, 3 RAPD markers and 1 PGM isozyme marker. Total genetic contribution of these makers to heat tolerance was 46.7%. Five of the nine markers distributed in one linkage group,the remaining 4 markers were located in separate groups. Thus the 9 heat tolerance linked markers distributed in 5 independent locations in the genome of Chinese cabbage.     

Genetic Transformation of Brassica campestris L. ssp.pekinensis via Agrobacterium－ with Bt Gene

By means of Agrobacterium-mediated transformation, 43 kanamycin-resistant buds of Chinese cabbage were got. PCR, PCR-Southern blot and dot blot analysis were used to identify and characterize the putative transgenic plants. 26 plants had the predicted bands of the fragment of npt Ⅱ gene. Insect bioassays of 4 transformants showed that toxic protein had been translated and the translation levels were different among these transformants.     

AFLP Marker Linked to Turnip Mosaic Virus Susceptible Gene in Chinese Cabbage (Brassica rapa L.ssp.pekinensis)

Turnip mosaic virus (TuMV) which has several strains causes the most important virusdisease in Chinese cabbage in terms of crop damage. In China, Chinese cabbage is infectedby a mixture of strains, breeding of cultivar for the TuMV resistance has become themajor aim. Screening the molecular marker linked to the TuMV-resistance gene formolecular assisted selection is the major method to improve the breeding efficiency. Inthis study, we used AFLP technique and the method of bulked segregant analysis(BSA) tostudy the progeny of Brp0058 x Brp0108, and identified two DNA molecular marker linked toTurnip mosaic virus-resistance gene with a recombination frequency 7.5 cM and 8.4 cM.     

A Genetic Linkage Map of Brassica carmpestris L.ssp.pekinensis (syn. B.rapa L.ssp.pekinensis )

A molecular genetic map of Chinese cabbage was constructed with a 102 recombinant inbred(RI) population from a cross of two cultivated Chinese cabbage lines 177 and 276, using AFLP and RAPDmarkers. 352 markers including 265 AFLP markers and 87 RAPD markers were integrated into 17 linkagegroups. It covered a total of 2 665.7 cM with an average interval of 7.6 cM. AFLP marker is efficient formap construction while it easily forms clusters to cause big gaps in map. A total of 13. 92% abnormal segrega-tion markers distributed in the map. The molecular genetic map is fundamental for gene localization, compar-ative genomics, and QTL mapping of important agronomic traits.     

优化白菜类蔬菜遗传转化体系的研究

采用农杆菌介导法将双元载体质粒pBI35S-AMF分别导入"上海青"白菜和"油青"菜心,对影响转化频率的抑菌剂和感染菌株等主要因素进行比较,优化了白菜类蔬菜的遗传转化体系.结果表明,在白菜类蔬菜的遗传转化体系中,选择氨苄青霉素作为转化农杆菌的抑菌剂为好,其抑菌浓度以300 mg/L为宜;预培养时间和共培养时间分别以3 d和2 d为适;LBA4404/pBI35S-AMF菌株的感染效率远高于EHA105/pBI35S-AMF.对KanR转化植株做进一步的分子检测结果显示,Southern印迹杂交阳性率为82.2%,转化频率达2.8%,且外源片段为多拷贝插入.多批次的转化结果证实,该体系的转化频率稳定.     

抗根肿病大白菜材料SSR分子标记的初步筛选

为了明确抗根肿病大白菜材料CCR12049中的抗病基因,进一步开发分子标记。以高抗根肿病的高代自交系大白菜CCR12049、高感根肿病的高代自交系大白菜CM12081、CCR12049和CM12081杂交得到的F₁及F₁自交构建的F₂分离群体为试材,通过人工接种鉴定、聚丙烯酰胺凝胶电泳和序列比对。结果显示,该抗病材料中的根肿病抗性由显性单基因控制;36对引物在2个亲本和F₁中初步筛选出4对有多态性的引物,在F₂中进一步验证,发现只有1对(cr-26)在F₂中的扩增结果与表型鉴定一致;2个亲本及F₁的PCR产物测序比对发现,在95~111 bp这个位置,抗病亲本和F₁的序列完全相同,但是感病材料在这个位置出现了17个碱基(TCTCTATCTCTTACGCA)的缺失。可以推断抗病材料可能是由于这17个碱基的插入从而表现出抗病性,该标记可以将抗感材料区分开,该标记可以作为一个初步筛选白菜抗根肿病的SSR分子标记来利用。     

大白菜萝卜细胞质雄性不育系RC_7花药发育的解剖学和同工酶研究

采用解剖学和聚丙烯酰胺凝胶电泳技术,研究了大白菜萝卜细胞质雄性不育系RC7及其保持系细胞学特征和蕾期小孢子发育过程中过氧化物酶(POD)同工酶、过氧化氢酶(CAT)同工酶、酯酶(EST)同工酶和淀粉酶(AMY)同工酶4种同工酶酶谱的变化。同工酶分析表明,RC7不育系的POD和AMY同工酶酶谱在小孢子发育的整个时期与保持系B7都存在明显差异,且CAT和EST同工酶酶谱在花粉粒成熟时期比保持系B7少了2条清晰的谱带,酶谱差异表达时期与细胞学上观察到的败育时期一致。结果表明,单核期RC7开始败育。     

Directional Breeding of An Oval-ecotype Male Sterile Line of Chinese Cabbage(Brassica campestris L. ssp. pekinensis)

[目的]探究大白菜定向转育卵圆生态型雄性不育系的方法。[方法]以大白菜核不育＂复等位基因遗传假说＂为理论依据,以甲型两用系‘AB12’为不育供体品系,以卵圆生态型可育品系‘06048’为待转育品系,采用杂交、回交、兄妹交和测交的方法,按照定向转育方案将核不育基因定向转育。[结果]各世代育性分离比率与理论相一致,成功育成了一种不育株率100%的具有‘06048’园艺性状的新核不育系,实现了核不育基因和园艺特性的同时转育。[结论]该研究成果验证此定向转育方案是可行的,进一步为基因型为 msms的其他园艺性状的大白菜定向转育提供理论基础,也可以推广应用到整个芸薹属其它经济作物中,极大的拓宽了优良核不育基因的实际应用范围。     

利用DH群体构建不结球白菜遗传连锁图谱

以不结球白菜品种暑绿的112个双单倍体(double haploid,DH)株系构成的群体作为作图群体,利用SRAP、SSR、RAPD和ISSR 4种分子标记来构建不结球白菜分子遗传连锁图谱.通过Mapmaker 3.0/EXP软件分析,得到1张不结球白菜分子遗传图谱,图谱总长度1 116.9 cM,共包括14个连锁群,186个多态性分子标记,其中包括114个SRAP、33个SSR、24个RAPD和15个ISSR标记,其中偏分离标记44个,占23.7%.每条连锁群上的标记数在4～27个之间, 连锁群的长度在30.3～165.8 cM的范围内,平均图距在3.4～11.1 cM之间,总平均距离6.0 cM.     

花心大白菜核基因雄性不育系的创制

以白菜核基因雄性不育系(Msms)为不育源,以花心大白菜宫古花蕊Y02(MsfMsf)为轮回亲本,采用连续回交,杂交和自交的转育方法,成功地将不育基因转入到可育品系Y02中,育成了不育度和不育株率均为100%,植物学性状与Y02相近的新核不育系GMS4。     

大白菜叶球相关性状的QTL定位与分析

 应用 35 2个标记位点的大白菜AFLP和RAPD图谱和一套品种间杂交获得的重组自交系群体 ,采用复合区间作图的方法 ,对大白菜叶球相关的 7个农艺性状进行QTL有定位及遗传效应研究。结果表明 ,在 14个连锁群上检测到 33个QTL ,其中控制生育期的有QTL 3个 ,控制外叶数的QTL有 3个 ,控制球高的QTL有 7个 ,控制球径的QTL有 5个 ,控制球叶数的QTL有 4个 ,控制球重的QTL有 4个 ,控制荒重的QTL有 7个。另外 ,估算了单个QTL的遗传贡献率和加性效应 ,其加性效应各不相等     

大白菜分子遗传图谱的构建与分析

 利用不同生态型的大白菜 (BrassicacampestrisL .ssp .pekinensis)栽培种高代自交系 177和 2 76杂交获得的 10 2份F6重组自交系 ,通过对AFLP和RAPD两种分子标记进行遗传分析 ,构建了包含 17个连锁群 ,由 35 2个遗传标记组成的大白菜连锁图谱 ,其中包括 2 6 5个AFLP标记和 87个RAPD标记。该图谱覆盖基因长度2 6 6 5 .7cM ,平均图距 7.6cM。AFLP标记对于增加图谱密度效率较高 ,但容易出现聚集现象 ,从而造成连锁群上有较大的空隙。连锁群上有 13.92 %的分子标记表现偏分离 ,偏分离标记在连锁群上聚集出现。     

不结球白菜花药组织培养影响因素的研究

以5个不结球白菜品种的花药为外植体,研究了低温预处理时间、不同采样时期、植物生长调节剂6-BA（6-benzyladenine）和NAA（naphthalene acetic acid）对花药萌发以及存活率的影响。结果表明：不结球白菜花药培养成活率因品种的不同而有所差异,华京的花药存活率较高;不同品种的不结球白菜适合的低温预处理时间也不同,华京适宜的低温预处理为1 d,而抗热605低温预处理5 d的效果较好;不添加6-BA和NAA的B5培养基更适合于花药的培养与成活。同时,不同的采样时期对花药的生活力有很大影响,4月下旬的花药生活力优于5月上中旬采样的花药。     

正交设计在大白菜愈伤组织诱导中的应用

通过L25(56)正交试验,优化及筛选最适合大白菜鲁白六号子叶及下胚轴愈伤组织诱导的4种植物生长调节剂和AgNO3的浓度组合.结果表明,在α-NAA、6-BA、TDZ、ABA和AgNO3中,α-NAA 对子叶愈伤组织诱导率的影响达极显著差异,ABA对子叶愈伤组织诱导率的影响达显著差异,确定以MS 1mg·L-1 α-NAA 1mg·L-1 6-BA 3mg·L-1 TDZ 0.5mg·L-1 ABA 10mg·L-1 AgNO3组合为最佳子叶愈伤组织诱导培养基,MS 0.8mg·L-1 α-NAA 2mg·L-1 6-BA组合为最佳下胚轴愈伤组织诱导培养基.试验中还发现,愈伤组织发生的同时还伴随着不定芽的发生,不定芽发生率较高的外植体,其产生的愈伤组织较少,且多为致密型愈伤组织.     

利用SRAP分子标记技术鉴定大白菜种子纯度

以大白菜品种多抗3及其父母本为研究材料,利用SRAP（相关序列扩增多态性）分子标记方法,通过对54对SRAP标准引物的筛选,获得了能区分大白菜多抗3及其亲本的引物Me4F/Em3R。采Me4F/Em3R引物对对5份多抗3系列商品种子纯度进行检验,种子的纯度分别为75.5%、72%、80.5%、68%和73%,与田间种植...     

白菜花药特异基因BcACT 的克隆与表达分析

    根据GenBank 数据库中已发布的肌动蛋白基因序列设计全长扩增引物,分别从白菜混合花蕾cDNA 和叶片基因组DNA 中克隆到各自的全长,其基因命名为BcA CT ,并利用RT‐PCR 技术研究该基因在白菜3个材料的不同器官以及保持系花蕾各部位的表达模式.结果表明:BcA CT 的DNA 全长为1704bp ,具有3个内含子,编码区长度为1134bp ,编码377个氨基酸;基因表达结果显示,BcA CT 基因在保持系Bcaj h97‐01B和Polima不育Bcpol97‐05A 的花蕾中表达,但表达模式存在差异,而在Ogura不育系Bcogu97‐06A 中未检测到;此外,BcA CT 基因的表达具有花药特异性,并且在花药发育过程中上调表达.