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Summary: Oilseed rape (Brassica napus L.), which has yellow flowers, is both an important oil crop and a traditional tourism resource in China, whereas the Orychophragmus violaceus, which has purple flowers, likely possesses a candidate gene or genes to alter the flower colour of oilseed rape. A previously established B. napus line has a particular pair of O. violaceus chromosomes (M4) and exhibits slightly red petals. In this study, the transcriptomic analysis of M4, B. napus (H3), and O. violaceus with purple petals (OvP) and with white petals (OvW) revealed that most anthocyanin biosynthesis genes were up‐regulated in both M4 and OvP. Read assembly and sequence alignment identified a homolog of AtPAP2 in M4, which produced the O. violaceus transcript (OvPAP2). The overexpression of OvPAP2 via the CaMV35S promoter in Arabidopsis thaliana led to different levels of anthocyanin accumulation in most organs, including the petals. However, the B. napus overexpression plants showed anthocyanin accumulation primarily in the anthers, but not the petals. However, when OvPAP2 was driven by the petal‐specific promoter XY355, the transgenic B. napus plants produced red anthers and red petals. The results of metabolomic experiments showed that specific anthocyanins accumulated to high levels in the red petals. This study illustrates the feasibility of producing red‐flowered oilseed rape, thereby enhancing its ornamental value, via the ectopic expression of the OvPAP2 gene. Moreover, the practical application of this study for insect pest management in the crop is discussed. [ABSTRACT FROM AUTHOR]

Key message: A high-density SNP map was constructed and several novel QTL for branch angle across six environments in Brassica napus were identified. Abstract: Branch angle is a major determinant for the ideotype of a plant, while the mechanisms underlying this trait in Brassica napus remain elusive. Herein, we developed one doubled haploid population from a cross involving one Capsella bursa- pastoris derived B. napus intertribal introgression line with the compressed branches and wooden stems, and constructed a high-density SNP map covering the genetic distance of 2242.14 cM, with an average marker interval of 0.73 cM. After phenotypic measurements across six environments, the inclusive composite interval mapping algorithm was conducted to analyze the QTL associated with branch angle. In single-environment analysis, a total of 17 QTL were detected and mainly distributed on chromosomes A01, A03, A09 and C03. Of these, three major QTL, qBA.A03-2, qBA.C03-3 and qBA.C03-4 were steadily expressed, each explaining more than 10% of the phenotypic variation in at least two environments. Compared with other results on rapeseed branch angle, these major QTL were newly detected. In QTL by environment interactions (QEI) mapping, 10 QTL were identified, and the QTL average effect and QEI effect were estimated. Of these, 7 QTL were detected in both single-environment analysis and QEI mapping. Based on the physical positions of SNPs and the functional annotation of the Arabidopsis thaliana genome, 27 genes within the QTL regions were selected as candidate genes, including early auxin-responsive genes, small auxin-up RNA, auxin/indoleacetic acid and gretchenhagen-3. These results may pave the way for deciphering the genetic control of branch angle in B. napus. [ABSTRACT FROM AUTHOR]

Nuclear-cytoplasmic interactions are predicted to be important in shaping the genetic changes in early stage of allopolyploidization. Our previous study shows the specific role of genome and cytoplasm affecting the chromosome pairing in Brassica hybrids and allotetraploids from pairwise crosses between three cultivated diploids with A, B and C genomes, respectively. Herein, to address how parental genomes and cytoplasm affects genomic, epigenetic and gene expression changes prior to meiosis in these hybrids and allopolyploids, their patterns of AFLP (Amplified fragment length polymorphism), mAFLP (Methylation AFLP) and cDNA-AFLP were compared with the progenitors, revealing the major absent bands within each genome. These changes varied under various cytoplasm backgrounds and genome combinations, following the significant order of AFLP> mAFLP> cDNA -AFLP. The frequencies of AFLP bands lost were positively correlated with the divergence degrees of parental genomes, but not obvious for those of mAFLP and cDNA-AFLP absent bands, and methylation change showed least variations among hybrids and within each genome. These changes within each genome followed the A>B>C hierarchy, except the highest rate of cDNA loss in B genome. Among three changes, only overall AFLP bands were significantly correlated with cDNA-AFLP, and their correlations varied within each genome. These changes in allotetraploids were mainly caused by genome merger rather than doubling. Parental genomes altered differently at three levels, responded to the types of cytoplasm and genome and their interaction or divergence. The result provides new clues for instant non-meiosis-driven genome restructuring following genome merger and duplication. [ABSTRACT FROM AUTHOR]

Hybridization and introgression represent important means for the transfer and/or de novo origination of traits and play an important role in facilitating speciation and plant breeding. Two sets of introgression lines in Brassica napus L. were previously established by its intertribal hybridizations with two wild species and long-term selection. In this study, the methods of amplified fragment length polymorphisms (AFLP), sequence-specific amplification polymorphism (SSAP) and methylation-sensitive amplified polymorphism (MSAP) were used to determine their genomic change, retrotransposon mobilization and cytosine methylation alteration in these lines. The genomic change revealed by the loss or gain of AFLP bands occurred for ∼10% of the total bands amplified in the two sets of introgressions, while no bands specific for wild species were detected. The new and absent SSAP bands appeared for 9 out of 11 retrotransposons analyzed, with low frequency of new bands and their total percentage of about 5% in both sets. MSAP analysis indicated that methylation changes were common in these lines (33.4–39.8%) and the hypermethylation was more frequent than hypomethylation. Our results suggested that certain extents of genetic and epigenetic alterations were induced by hybridization and alien DNA introgression. The cryptic mechanism of these changes and potential application of these lines in breeding were also discussed. [ABSTRACT FROM AUTHOR]

We introduce and review Brassica crop improvement via trigenomic bridges. Six economically important Brassica species share three major genomes (A, B, and C), which are arranged in diploid (AA, BB, and CC) and allotetraploid (AABB, AACC, and BBCC) species in the classical triangle of U. Trigenomic bridges are Brassica interspecific hybrid plants that contain the three genomes in various combinations, either triploid (ABC), unbalanced tetraploid (e.g., AABC), pentaploid (e.g., AABCC) or hexaploid (AABBCC). Through trigenomic bridges, Brassica breeders can access all the genetic resources in the triangle of U for genetic improvement of existing species and development of new agricultural species. Each of the three Brassica genomes occurs in several species, where they are distinguished as subgenomes with a tag to identify the species of origin. For example, the A subgenome in B. juncea (2n = AABB) is denoted as Aj and the A subgenome in B. napus (2n = AACC) as An. Trigenomic bridges have been used to increase genetic diversity in allopolyploid Brassica crop species, such as a new-type B. napus with subgenomes from B. rapa (Ar) and B. carinata (Cc). Recently, trigenomic bridges from several sources have been crossed together as the ‘founders’ of a potentially new allohexaploid Brassica species (AABBCC). During meiosis in a trigenomic bridge, crossovers are expected to form between homologous chromosomes of related subgenomes (for example Ar and An), but cross-overs may also occur between non-homologous chromosomes (for example between A and C genome chromosomes). Irregular meiosis is a common feature of new polyploids, and any new allotetraploid or allohexaploid Brassica genotypes derived from a trigenomic bridge must achieve meiotic stability through a process of diploidisation. New sequencing technologies, at the genomic and epigenomic level, may reveal the genetic and molecular basis of diploidization, and accelerate selection of stable allotetraploids or allohexaploids. Armed with new genetic resources from trigenomic bridges, Brassica breeders will be able to improve yield and broaden adaptation of Brassica crops to meet human demands for food and biofuel, particularly in the face of abiotic constraints caused by climate change. [ABSTRACT FROM AUTHOR]

Examines the cytogenetics of intergeneric hybrids between cultivated Brassica species and Orychophragmus violaceus in China. Occurrence of parental genomes separation during mitosis and meiosis; Chromosome behavior of hybrids with several Brassica diploids; Identification of Brassica homozygous plants and aneuploids with various chromosome constitution.

Objective: To observe the effects of moxibustion combined with autohemotherapy of acupoint injection and simple moxibustion for allergic rhinitis(AR) with qi deficiency of lung and spleen and to explore its mechanism., Methods: By random number table,75 patients who matched the criteria were assigned into a moxibustion combined with autohemotherapy of acupoint injection group(a combination group,37 cases) and a moxibustion group(38 cases). In the combination group,moxibustion was used at bilateral Yingxiang(LI 20) and injection bila-teral Feishu(BL 13),Pishu(BL 20) and Zusanli(ST 36). In the moxibustion group,moxibustion was applied bilaterally at all the above acupoints. Acupoint injection was given twice a week,and moxibustion once a day,seven days as a course. The patients were observed for four courses and followed up half a year after treatment. Rhinoconjunctivitis quality of life questionnaire(RQLQ) was compared before and after treatment and at follow-up. The short-term and long-term effects as well as the changes of interferon- γ (IFN- γ ),interleukin-4(IL-4) and immunoglobulin E(IgE) were observed in the two group., Results: After treatment,the obviously effective rate of the combination group was 75.68%(28/37),which was higher than 52.63%(20/38) of the moxibustion group( P <0.05). But at follow-up, the obviously effective rate of the moxibustion group was 47.37%(18/38),which was better than 24.32%(9/37) of the combination group( P <0.05). Life quality of the two group in all aspects after treatment and at follow-up were apparently improved compared with the baseline( P <0.01, P <0.05). After treatment,the life quality,sleep condition,non nasal-eye symptoms,behavior issue of the combination group were superior to those of the moxibustion group(all P <0.05),and at follow-up,the above outcomes,the eye and nasal symptoms as well as emotional response of the mo-xibustion group were better(all P <0.05). There was statistical significance in the two group about serum IFN- γ ,IgE,IL-4 before and after treatment( P <0.01, P <0.05),and significance existed between the two groups( P <0.05)., Conclusions: Moxibustion combined with autohemotherapy of acupoint injection can effectively improve the short-term quality of life of AR with qi deficiency of lung and spleen. The mechanism may be related to balancing the immune response of Th1 and Th2.