结球甘蓝的离体快繁技术研究

以结球甘蓝无菌苗的胚轴和子叶为材料，几乎不生长愈伤组织，分化出不定芽。不定芽在添加6-BA的MS培养基上增殖很快，适宜的生根培养基为1/2MS+IBA0.5mg/L+ NAA0.1mg/L。通过增加培养基中糖和琼脂粉的用量，提高培养时的光照强度等有效控制了玻璃苗的产生。     

Effect of mass selection in nil-competition conditions on some traits of four cabbage populations

Mass selection with controlled pollination for heading, resistance to early bolting, fewer frame leaves relative to head size and few cover leaves, was applied for three cycles in four Greek open‐pollinating populations (OPPs) of cabbage in nil‐competition conditions (honeycomb method). The cycle 0 OPPs with their respective cycle 3 OPPs were tested under competition conditions (growers density), in two successive years, to assess the selection response for heading, resistance to early bolting, number of cover leaves and yield. In most cases, the selection response was significant at P = 0.01 or even at P = 0.001. For example, the mean increase of yield estimated over all OPPs across 2 years was 36%, without any undesirable changes in dry matter and soluble solids contents.     

春甘蓝抽薹的生理与相关基因转录分析

本研究以高代自交获得的4份具有不同抽薹时间且遗传稳定的春甘蓝品系为材料,在观察其园艺学性状的基础上,分析了抽薹性状与可溶性蛋白和可溶性糖含量之间的关系,结果显示,耐抽薹春甘蓝品系的可溶性蛋白和可溶性糖含量低于不耐抽薹的,抽薹前春甘蓝的可溶性蛋白和可溶性糖含量也均低于抽薹后的.进一步的转录分析结果表明,5个与植物抽薹开花...     

甘蓝种质资源遗传多样性的SRAP分析

本研究利用26对SRAP引物组合对46份甘蓝材料的遗传多样性和亲缘关系进行了分析,以期为甘蓝亲本选配提供参考。结果表明这26对引物共扩增出稳定清晰的条带439条,其中多态性条带为227条,多态性位点比率为51.7%。根据SRAP扩增结果,应用NTSYSpc2.1数据分析软件计算各品种间的遗传相似系数,结果表明这些材料间的遗传相似系数的变化范围是0.41～0.99。在相似性系数为0.568的水平上,可将46份甘蓝品种分为4大类,除第4类是形态特征明显有别于其它材料的抱子甘蓝外,其余3类结球甘蓝的主要聚类依据是其开花时间依次间隔一个星期左右。     

结球甘蓝细胞质雄性不育(CMS)类型的分子鉴定

本研究以高代回交转育获得的6个不育率和不育度均达100%且遗传稳定的结球甘蓝胞质雄性不育系为材料,通过对orf138与orf222基因的特异扩增发现,所鉴定的24个株系64个单株结球甘蓝CMS植株中59个单株既含有orf138基因,也有orf222基因.两种基因共存的结果暗示,该类CMS可能是ogura和nap两种类型的杂合体.进一步的序列分析结果表明,6个结球甘蓝CMS中所扩增获得的orf138基因与来自萝卜CMS的orf138基因序列完全相同;而除Bo134-2 CMS的orf222基因与甘蓝型油菜CMS orf222基因相比对有2个核苷酸差异外,其余5个CMS的orf222基因与甘蓝型油菜nap CMS orf222基因的相似性均为100%.其中,Bo134-2 CMS的orf222基因第191 bp的变异导致第64位氨基酸由精氨酸(R)突变成了赖氨酸(K).     

组织培养、分子标记和QTL技术在青花菜育种中的应用

育种是优异种质资源基因的重组。除传统新种质产生的方法外,通过组织培养、分子标记等技术来扩大物种的遗传基础已成为新种质资源形成的重要手段。青花菜,芸薹属甘蓝中以绿色花球为食用器官的一个变种,近年来在中国的种植面积越来越大,利用现代生物技术手段进行青花菜育种研究工作也越来越受到关注和重视。本文综述了游离小孢子培养、原生质体融合和转基因技术在青花菜种质资源创制中的应用,分析了各种方法存在的问题,并对青花菜遗传图谱构建、花球相关农艺性状及抗病性QTL/基因定位研究进行了探讨,并对其未来研究方向做了展望。     

甘蓝BoKIN1基因的ploy(A)位点的预测及其频率分析

多聚腺苷酸化(Polyadenylation)是真核生物中一种重要的pre-mRNA加工机制,是mRNA成熟的一个必经过程。为了解甘蓝BoKIN1基因的多聚腺苷酸化加工情况,本研究从甘蓝全基因组数据库中下载得到BoKIN1基因序列,并利用生物信息学手段分析了BoKIN1的基因结构和基因表达。研究结果显示:BoKIN1基因在花器官中表达最高;然后基于EST文库发现了3个ploy(A)位点,并计算了这些ploy(A)位点在premRNA加工过程中被选择的大致频率情况,结果显示BoKIN1基因在pre-mRNA加工过程中至少有6个ploy(A)位点可供选择加尾,其中AP4位点被选择加尾的频率最高,其次是AP5位点。因此选择AP4位点加尾后形成的mRNA是转录后加工的主要产物。通过本研究我们确定了甘蓝类BoKIN1基因6个选择性加尾位点及其3'UTR的主要产物和次要产物,可对于未来进一步利用这些3'UTR奠定基础。     

Identification of a Monogenic Dominant Male Sterility Mutant in Broccoli (Brassica oleracea var. italica Plenck)

After mutagenic treatment with NMU (nitroso-methylurea) flower buds and flower-bud pedicels of broccoli were cultivated in vitro. Among regenerated MJ plants, one male sterile, but female fertile mutant was found, for which a monogenic dominant inheritance of male sterility was demonstrated. A scheme to utilize dominant controlled genie male sterility in Brassica oleracea for hybrid breeding is discussed.     

西兰花穴盘育苗技术研究

本试验以西兰花（Brassica oleracea L.var.italica Planch）为材料,研究了穴盘规格、基质、基肥对西兰花穴盘幼苗生长发育的影响。结果如下：不同的穴盘规格、基质和基肥对西兰花幼苗生长发育有较大的影响,实际大田生产中要培育壮苗,可以采用72孔穴盘,基质可选用轻基质（泥炭：珍珠岩：蛭石=2：1：1）,也可在轻基质中掺和一定的比例食用菌渣或园土,并拌入一定量的基肥（复合肥或缓释性肥料）。     

白菜型油菜DFR基因的克隆与序列分析

By using RACE (rapid amplification ofcDNA ends) based homologous cloning strategy, we have successfully isolated the genomic and full-length cDNA sequences of a gene encoding typical DFR (dihydroflavonol-4-reductase) from black-seeded Brassica campestris L. var. oleifera DC.. The gene, designated BcDFR here, is 1 722bp in length and harbors 5 introns with typical splice sites of plant DFR genes. BcDFR cDNA is 1311bp in length with a 1 158bp ORF as well as a 25bp 5‘ UTR and a 128bp 3‘ UTR. The encoded BcDFR protein is 385 aa with a calculated Mw of 42.85kD and a pI value of 5.55. The nucleotide and amino acid sequences of this gene share extensive homologies to plant DFR genes of wide origins especially high similarities to Cruciferous DFR genes. Sequence analyses such as phylogenetic analysis, conserved domain search and substrate specificity region detection all indicated that BcDFR gene is a quite potentially biofunctional gene. Its cloning enables us to further dissect the possible relatedness between DFR gene and Brassica seed coat color traits and to create transgenic novel yellow-seeded rapeseed germplasm through antisense- or RNAi-suppression of DFR gene expression in black-seeded elite cultivars.     

Identification and mapping of a quantitative trait locus controlling extreme late bolting in Chinese cabbage (Brassica rapa L. ssp. pekinensis syn. campestris L.) using bulked segregant analysis

DNA markers linked to a locus controlling an extreme late bolting trait, which was originally found in a local cultivar of a non-heading leafy vegetable,‘Osaka Shirona Bansei’ (Brassica rapa L. ssp. pekinensis syn. campestris L.) were identified using bulked segregant analysis. A doubled haploid (DH) line, DH27, which is a progeny of ‘Osaka Shirona Bansei’, shows extreme late bolting, and bolts without vernalization. DH27 was crossed with a normal bolting DH line, G309. The plantlets of the parents, F₁ and F₂, were vernalized and then grown in a greenhouse. The bolting time of F₂ plants showed a continuous distribution from 19 to 231 days after vernalization (DAV), suggesting the effects of a few major genes and polygenes. Possible linkage markers for this trait were screened by modified bulked segregant analysis (BSA). The BSA using four bulks suggested that a 530-bp RAPD band RA1255C was linked to a locus controlling the bolting trait. The RAPD band was cloned and used as a probe to detect RFLP. The fragment detected a single locus, BN007-1,the segregation of which in the F₂ population matched that of RA1255C. Three other RAPDs were found to be linked to BN007-1. A quantitative trait locus(QTL) affecting the bolting time was detected around BN007-1 using MAPMAKER/QTL. Since the difference between bolting times of both the parental genotypes in the F₂ was 138 days, these markers may be useful for a marker-assisted selection (MAS) in the breeding program for late bolting or bolting-resistant cultivars in B. rapa crops. This revised version was published online in July 2006 with corrections to the Cover Date.     

自花授粉诱导的甘蓝功能基因BoSPI的克隆与表达分析

自交不亲和性是甘蓝在长期进化过程中形成的防止自交衰败、促进杂交优势的一种复杂而完善的遗传机制。克隆自交不亲和性相关基因对甘蓝自交不亲和性的深入研究和利用有重要意义。本研究通过挖掘0~60 min自花和异花授粉的甘蓝柱头转录组数据, 筛选到一个受自花授粉诱导上调表达的基因, 命名为BoSPI。BoSPI开放阅读框534 bp, 编码177个氨基酸, 理论等电点为4.21, 不包含信号肽和跨膜区, 含有4个保守的EF-hand结构域。BoSPI基因起始密码子上游2000 bp的核苷酸序列中含有真菌诱导响应、代谢调节以及器官形成等应答元件。BoSPI基因在大肠杆菌中可诱导表达为17 kD的蛋白。BoSPI在柱头中表达量最高, 在花瓣、萼片、叶片、雄蕊表达量较低。BoSPI蛋白被定位在细胞膜和细胞质。自花授粉30 min后对BoSPI基因的诱导表达显著增强。表明BoSPI参与了柱头响应自花花粉刺激的分子过程, 可能是实现甘蓝自交不亲和性相关的某种新功能基因。