芥菜型油菜TT1基因的克隆和SNP分析

拟南芥的TT1基因(编码含有WIP结构域的锌指蛋白)对种皮的发育和颜色的形成具有重要的调控作用。本研究利用同源克隆和RACE技术分离了芥菜型油菜TT1基因,在芥菜型油菜黄黑籽材料的种皮中进行转录水平的分析,比较了黑籽油菜与黄籽油菜基因序列的差异,并采用等位基因特异(allele-specific)PCR技术对可能存在的单核苷酸多态位点进行验证。结果表明,芥菜型油菜TT1基因的DNA序列全长为2197bp,包含1个内含子,与甘蓝型油菜TT1-1基因的DNA序列的相似性为99%,与拟南芥的TT1基因DNA序列的相似性为85%;推导的TT1蛋白序列为300氨基酸残基,理论分子量为33.97kD,等电点为6.99;TT1在所有材料的种皮中均检测到表达;比较紫叶芥、四川黄籽、NILA和NILB的TT1基因序列,共发现8个核苷酸变异位点,均在基因的外显子区域,其中紫叶芥和NILA的序列相同,四川黄籽和黒籽近等基因系NILB的序列相同。与紫叶芥相比,黒籽近等基因系NILB有8个核苷酸差异,但种皮颜色与紫叶芥一样,均为黑色,TT1基因这些位点的突变并不影响芥菜型油菜种皮的颜色。通过等位特异PCR可以区分来自四川黄籽与紫叶芥的TT1基因。     

芥菜型油菜与甘蓝型油菜嫁接嵌合体的性状表现

以芥菜型油菜(B. juncea)作砧木,以甘蓝型油菜(B. napus)作接穗,形成嫁接嵌合体（以下简称“甘+芥”嫁接嵌合体）,对其植物学性状、农艺性状和32P标记的难溶性磷矿粉的吸收能力进行了研究。结果表明,“甘+芥”嫁接嵌合体除叶片出现紫色性状外,其他性状与甘蓝型油菜没有差异,但其农艺性状明显优于甘蓝型油菜和芥菜型油菜。其根系对肥料中难溶性磷吸收能力强,而且多数转移到地上部分,在体内分布较合理。     

贵州芥菜型油菜地方品种的配合力分析

对贵州芥菜型油菜地方品种用双列杂交并测定配合力表明, 品种间存在显著的遗传差异, 其中, 株高、一二次总有效分枝数、单株结角数、单株产量受加性和非加性两种遗传效应共同作用; 千粒重以加性效应为主。品种单株产量及其因子一般配合力差异显著。平坝苦油菜 （一） 和贵定苦油菜 （一） 的一般配合力较高。单株产量的特殊配合力以贵定苦油菜 （一） ／平坝苦油菜 （一） 组合最高。     

以NIRS定量分析甘蓝型油菜、芥菜型油菜饼粕赖氨酸含量

作物品质育种工作需要快速和准确,并且不破坏种子的情况下来测定有关参数,但传统的品质鉴定方法在分析速度和效率以及种子的留存上存在局限性,难以满足上述要求.近红外反射光谱分析技术(near infrared reflectance spectroscopy,NIRS)是一种不需要对种子进行前处理,即可得到几乎全部农产品品质参数的分析技术[1].NIRS技术现已广泛应用于农产品[2]、食品[3]、果汁[4]、饲料[5]等的分析检测.我国该技术的应用虽起步较晚,但在农作物品质分析上已取得了一些可喜的进展[6,7].用近红外仪测试油菜种子的含油量、饼粕的蛋白质含量与硫甙含量,已基本接近和达到化学分析所需求的精度[8].     

芥菜型油菜主要农艺性状遗传力和遗传进度初步研究

对芥菜型油菜主要农艺性状的遗传力、变异系数和遗传度进行了研究,结果表明：遗传力较高的性状诊次是全株有效角果数、单株生产力,每角果粒,第一有效分枝部位、主花序有效长度和千粒重,同时,单株生产力,第一有效分枝部位和全株有效角果数的变异系数和遗传进度也较高,说明这几个性状在早期世代选择效果良好;株高、角果长和一次有效分枝数的遗传力和遗传进度均较低,宜在杂交后期世代进行选择。     

芥菜型油菜毛状根诱导体系构建及TTG1基因功能初步研究

黄籽油菜具有种皮薄、出油率高等优点, 研究油菜黄籽的形成具有重要的意义。前期研究表明, TTG1 (TRANSPARENT TESTA GLABRA 1)基因参与了油菜种皮颜色的形成。本研究利用发根农杆菌A4菌株诱导了芥菜型油菜四川黄籽的毛状根, 并研究了菌液浓度和外植体部位对诱导率的影响。结果表明, 菌液浓度OD值为0.8时, 诱导效率最高, 平均为71.5%; 外植体中下胚轴的发根率最高, 平均为87.3%。在四川黄籽毛状根中过表达TTG1基因, 发现原花色素合成途径中的DFR (dihydroflavonol4-reductase)、ANS (anthocyanidin synthase)和BAN (anthocyanidin reductase)基因的表达受到抑制。本研究优化了油菜毛状根的诱导体系, 为利用毛状根体系进行基因功能验证提供了新的思路和方法。     

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.     

贵州芥菜型油菜含油率与各生育阶段的遗传相关及通径分析

以贵州芥菜型油菜地方品种，进行含油率与各生育阶段的遗传相关与通径分析。结果表明：５个生育阶段与含油率呈不同程度的遗传相关，它们的大小顺序为：抽苔至初花〉现蕾至抽苔〉出苗至现蕾〉终花至成熟〉初花至终花。５个生育阶段对含油率的直接通径大小依次为：出苗至现蕾〉初花至终花〉抽苔至初花〉终花至成熟〉现蕾至抽苔。从遗传相关、通径分析的大小排列顺序可看出：出苗至现蕾、初花至终花、抽苔至初花这３个生育阶段是影响油     

日喀则地区芥菜型油菜农家种单株产量的通径分析

对西藏日喀则地区9个芥菜型油菜农家种单株产量进行相关通径分析.结果表明,该地区芥菜型油莱产量性状变异度为21%～49%,表现出较为丰富的多样性特征;主花序长的直接通径系数最大(0.5131),其次是角粒数(0.3801)、一次有效分枝数(0.2361)、千粒重(0.2138)、单株有效角果数(0.1250)、分枝部位(-0.1452);一次有效分枝数、千粒重、单株有效角果数通过主花序长对单株产量的间接通径系数较大,且与单株产量呈显著、极显著相关,因此丰产性状的选择中,可以把这3个性状组合为高产选择的指标.     

Erucic acid heredity in Brassica juncea - some additional information

Genetic studies were undertaken to reassess erucic acid heredity in Brassica juncea. Analysis of segregation in F₂ and BC₁ generations from two zero × high erucic acid crosses indicated that higher erucic acid in B. juncea was controlled by two dominant genes with additive effects, whereas segregation in a cross involving ‘CCWF 16′, a genotype having intermediate erucic acid (25.6%), and a zero erucic acid strain, indicated monogenic dominant control for intermediate erucic acid content. The B. juncea strain ‘CCWF 16’ was developed by hybridizing high‐erucic acid B. juncea cv.‘WF‐1’ with a ‘0’ erucic B. rapa cv.‘Candle’ followed by backcrossing with ‘WF‐1’ and half‐seed selection for low erucic acid in each backcross generation. This strategy resulted in substitution of the high erucic acid allele present in the A genome of B. juncea (AABB) by the zero erucic acid allele associated with ‘A’ genome of ‘Candle’. The intermediate erucic acid content in ‘CCWF 16’ was thus attributed to a gene present in the ‘BB’ genome. Experimental data clearly suggested that the gene (E₂) associated with the A genome had a greater contribution to the total erucic acid content in B. juncea than the gene (E₁) located on the B genome. This provided experimental evidence for a previous suggestion of unequal contributions of two dominant genes (E₁= 12%, E₂= 20%) to high erucic acid content in conventional digenomic Brassica species.     

甘蓝型油菜芥酸含量的三重测交分析

本文用扩展三重测交设计研究了甘蓝型油菜芥酸及其他脂肪酸含量的遗传。结果表明,芥酸的上位性效应不显著,主要受加性效应控制,显性作用较小。显性方向为正,一级统计量分析不显著,二级统计量分析达显著水平。方差分量 D,H 和 F 的估值分别为358.15—362.22,8.74—18.00和51.77—53.26。平均显性度为0.1553—0.2242,优势比为0.     

Characterization of FAE1 in the zero erucic acid germplasm of Brassica rapa L.

The modification of erucic acid content in seeds is one of the major goals for quality breeding in oil-yielding Brassica species. However, few low erucic acid (LEA) resources are available, and novel LEA genetic resources are being sought. Fatty acid elongase 1 (FAE1) is the key gene that controls erucic acid synthesis. However, the mechanism for erucic acid synthesis in B. rapa lacks systematic study. Here, we isolated zero erucic acid lines from 1981 Chinese landraces of B. rapa and found that the formation of LEA is not attributable to variations in FAE1 coding sequences, as reported for B. napus, but may be attributable to the decrease in FAE1 expression. Moreover, the FAE1 promoter sequences of LEA and high erucic acid materials shared 95% similarity. Twenty-eight bases deletions (containing a 24-base AT-rich region) were identified approximately 1300 bp upstream from the FAE1 start codon in the LEA accessions. The genotype with the deletions co-segregated with the LEA trait in the segregating population. This study isolated an LEA B. rapa resource that can be exploited in Brassica cultivation. The promoter variations might modify the expression level of FAE1, and the results shed light on novel regulation mechanisms for erucic acid synthesis.     

Yield, Oil Content and Fatty Acid Composition Evaluated in Androgenetic Plants in Brassica juncea

Homozygous diploids were obtained through anther culture in Indian mustard, Brassier juncea, cultivar TM-4, Seeds could be harvested from 97 such plants in the A; generation. The androgenetic lines were further selected and the yield and yield components were compared in the A₄ and A₅ generations, Androgenetic lines showed variations for most of the characters studied including seed oil content and fatty acid composition. However, it was possible to recover seven lines out of 25 which were equal in seed yield and three equal in oil content compared TO the anther donor parent TM-4.     

Independent Inheritance of Erucic Acid Content and Flower Colour in the C-Genome of Brassica napus L.

The synthetic Brassica napus L. line No7076 was obtained from a cross between yellow-flowered and zero-erucic turnip rape (B. campestris) Sv85-38301 and white-flowered and high-erucic (41.4%) B. oleracea ssp. alboglabra No6510. This synthetic B. napus is pale-flowered and has an average erucic acid content of 25.8 %. It was crossed with the yellow-flowered and zero-erucic B. napus line SvS4-2S053 and segregation of the erucic acid content and flower colour was studied in F₁ and F₂ generations. The high erucic acid content was controlled by a single gene in the C-genome and was additively inherited. Strong evidence was obtained in support of independent segregation of the erucic-arid content and the flower colour characters controlled by the C-genome of B. napus.     

甘蓝型油菜遗传图谱的构建及芥酸含量的QTL分析

一个由甘蓝型油菜品种Quantum (黄花、低芥酸)和人工合成的甘蓝型油菜品系No.2127-17（白花、高芥酸）为亲本材料建立的DH群体中芥酸呈现单基因的遗传模式。为了发展与芥酸紧密连锁的分子标记对其实行有效的控制,随机选择121个结实正常的DH系为作图群体,利用SSR和RAPD标记构建了一张甘蓝型油菜的遗传连锁图谱。在亲本间检测     

双低杂交油菜青杂6号的特征特性及栽培要点

介绍了甘蓝型杂交油菜新品种青杂6号的特征特性以及在国家区试、国家生产试验中的产量表现,并对该品种的推广适宜地区和栽培技术进行了总结.     

Relationship Between Leaf Nitrogen and Photosynthetic Characteristics in Brassica juncea and B. campestris

The relationship between leaf nitrogen content (N) versus photosynthetic rate (PN) and other associated parameters was examined in Brassica juncea , cv. Pusa Bold and B campestris , cv. Pusa Kalyani. Leaf N, specific leaf weight (SLW), leaf area and PN were significantly higher in B. juncea , while the chlorophyll content was significantly lower compared to Brassica campestris. A significant positive correlation was obtained between leaf N content and photosynthetic rate in both species. Similarly, SLW was also positively related with leaf N content, Brassica juncea showed higher photosynthetic nitrogen use efficiency (PNUE) than B campestris. Leaf N and PNUE were negatively associated. This was attributed to a low investment of N in photosynthesis related reactions and/or partitioning of N towards compounds functionally unrelated to photosynthesis. This attribution is further supported by the negative relationship obtained between SLW and PNUE.     

Molecular marker analysis of the linkage drag around the FAE1 loci of Brassica juncea during conventional backcross breeding

A post-transfer investigation was carried out to analyze the process of gene introgression in a conventional backcross-breeding program taking low erucic acid as target trait in Brassica juncea. FAE1 locus is involved in the elongation of oleic acid (C18:1) to erucic acid (C22:1). A high concentration of erucic acid in the seeds of Brassica species has been reported to be nutritionally undesirable. Molecular markers like AFLP markers, microsatellite markers, and gene-based SNP markers were used to determine the size of the donor parent chromosomal segments retained around the FAE1 genes in the individuals selected from different backcross generations. The genotype of the individuals was inferred from the genotype of the markers and the graphical genotypes were constructed using GGT software. Molecular marker analysis led to the identification of rare recombinants near the target locus with reduced size of introgressed segment from the donor parent. Based on the present study, we propose that marker-assisted backcross breeding in B. juncea could prove to be a promising tool for the transfer of many quality traits from unadapted East European germplasm to Indian cultivars.