Genetic Variation and Correlation Analysis on Seed Oil and Protein Content of Brassica campestris L. Germplasm Resources

The content of oil and protein in 84 germplasm materials of Brassica campestris L. from all over the country was tested. In Guiyang environment, the oil content and protein content of these materials showed abundant variation, and were divided into three groups. Correlation analysis showed that there was a significant negative correlation between oil content and protein content of B. campestris L. seeds, and the application and formation mechanism of the negative correlation were also discussed

Variation and Statistic Analysis of Agronomic Traits of Recombinant Inbred Lines of Brassica juncea L.

Correlation analysis and principal component analysis (PCA) were conducted for some agronomic traits of 139 recombinant inbred lines of Brassica juncea L. The results showed that under the environmental conditions in Guiyang, the flowering time, number of seeds per silique, plant height and thousand seed weight differed significantly among different lines. The results of principal component analysis showed that the lines could be classified into three groups. The results of Pearson correlation tests showed that the plant height was positively correlated with the flowering time (P<0.05), and the thousand seed weight was negatively correlated with the flowering time and number of seeds per silique (P<0.01)

Variation and Correlation of Erucic Acid, Oleic Acid and Glucosinolate Contents in Brassica rapa Seeds

In order to screen and identify excellent breeding resources and provide basic materials for Brassica rapa breeding, the contents of erucic acid, oleic acid and glucosinolate in 84 samples of B. rapa were determined by near-infrared spectroscopy, and the correlations among them were also analyzed. The results showed that the content of erucic acid and oleic acid were significantly negatively correlated, the contents of erucic acid and glucosinolate were significantly positively correlated, while the contents of oleic acid and glucosinolate were significantly negatively correlated; principal component analysis (PCA) were performed on the population materials, factors 1 and 2 were extracted for plotting, factor 1 and factor 2 could explain 73.7% and 23.2% of the phenotypic variation, respectively; through cluster analysis, 79 materials aggregated to form group I, and 5 special variants deviated from the population. The variation of erucic acid, oleic acid and glucosinolates in B. rapa populations was rich and there was significant correlation. Through cluster analysis, 5 excellent B. rapa breeding materials (No. 32, No. 45, No. 46, No. 50, and No. 59) were screened

Quantitative Trait Locus Mapping Combined with RNA Sequencing Reveals the Molecular Basis of Seed Germination in Oilseed Rape

Rapid and uniform seed germination improves mechanized oilseed rape production in modern agricultural cultivation practices. However, the molecular basis of seed germination is still unclear in Brassica napus. A population of recombined inbred lines of B. napus from a cross between the lower germination rate variety &lsquo;APL01&rsquo; and the higher germination rate variety &lsquo;Holly&rsquo; was used to study the genetics of seed germination using quantitative trait locus (QTL) mapping. A total of five QTLs for germination energy (GE) and six QTLs for germination percentage (GP) were detected across three seed lots, respectively. In addition, six epistatic interactions between the QTLs for GE and nine epistatic interactions between the QTLs for GP were detected. qGE.C3 for GE and qGP.C3 for GP were co-mapped to the 28.5&ndash;30.5 cM interval on C3, which was considered to be a novel major QTL regulating seed germination. Transcriptome analysis revealed that the differences in sugar, protein, lipid, amino acid, and DNA metabolism and the TCA cycle, electron transfer, and signal transduction potentially determined the higher germination rate of &lsquo;Holly&rsquo; seeds. These results contribute to our knowledge about the molecular basis of seed germination in rapeseed

Exploration into Natural Variation Genes Associated with Determinate and Capitulum-like Inflorescence in <i>Brassica napus</i>

Brassica napus is a globally important vegetable and oil crop. The research is meaningful for the yield and plant architecture of B. napus. In this study, one natural mutant line with determinate and capitulum-like inflorescence was chosen for further study. Genetic analysis indicated that the segregation patterns of inflorescences in the F2 populations supported a digenic inheritance model, which was further approved via the BSA-Seq technique. The BSA-Seq method detected two QTL regions on C02 (14.27–18.41 Mb) and C06 (32.98–33.68 Mb) for the genetic control of determinate inflorescences in MT plants. In addition, the expression profile in MT compared with WT was analyzed, and a total of 133 candidate genes for regulating the flower development (75 genes, 56.4%), shoot meristem development (29 genes, 21.8%), and inflorescence meristem development (13 genes, 9.8%) were identified. Then one joint analysis combing BSA-Seq and RNA-Seq identified two candidate genes of BnaTFL1 and BnaAP1 for regulating the MT phenotype. Furthermore, the potential utilization of the MT plants was also discussed

Detection and Molecular Characterization of Two <i>FAD3</i> Genes Controlling Linolenic Acid Content and Development of Allele-Specific Markers in Yellow Mustard (<i>Sinapis alba</i>)

<div><p>Development of yellow mustard (<i>Sinapis alba</i> L.) with superior quality traits (low erucic and linolenic acid contents, and low glucosinolate content) can make this species as a potential oilseed crop. We have recently isolated three inbred lines Y1127, Y514 and Y1035 with low (3.8%), medium (12.3%) and high (20.8%) linolenic acid (C18∶3) content, respectively, in this species. Inheritance studies detected two fatty acid desaturase 3 (<i>FAD3</i>) gene loci controlling the variation of C18∶3 content. QTL mapping revealed that the two <i>FAD3</i> gene loci responsible for 73.0% and 23.4% of the total variation and were located on the linkage groups Sal02 and Sal10, respectively. The <i>FAD3</i> gene on Sal02 was referred to as <i>SalFAD3.LA1</i> and that on Sal10 as <i>SalFAD3.LA2</i>. The dominant and recessive alleles were designated as <i>LA¹</i> and <i>la¹</i> for <i>SalFAD3.LA1</i>, and <i>LA²</i> and <i>la²</i> for <i>SalFAD3.LA2</i>. Cloning and alignment of the coding and genomic DNA sequences revealed that the <i>SalFAD3.LA1</i> and <i>SalFAD3.LA2</i> genes each contained 8 exons and 7 introns. <i>LA¹</i> had a coding DNA sequence (CDS) of 1143 bp encoding a polypeptide of 380 amino acids, whereas <i>la¹</i> was a loss-of-function allele due to an insertion of 584 bp in exon 3. Both <i>LA²</i> and <i>la²</i> had a CDS of 1152 bp encoding a polypeptide of 383 amino acids. Allele-specific markers for <i>LA¹</i>, <i>la¹</i>, <i>LA²</i> and <i>la²</i> co-segregated with the C18∶3 content in the F₂ populations and will be useful for improving fatty acid composition through marker assisted selection in yellow mustard breeding.</p></div

Exploring the basis of 2-propenyl and 3-butenyl glucosinolate synthesis by QTL mapping and RNA-sequencing in Brassica juncea.

Brassica juncea is used as a condiment, as vegetables and as an oilseed crop, especially in semiarid areas. In the present study, we constructed a genetic map using one recombinant inbred line (RIL) of B. juncea. A total of 304 ILP (intron length polymorphism) markers were mapped to 18 linkage groups designated LG01-LG18 in B. juncea. The constructed map covered a total genetic length of 1671.13 cM with an average marker interval of 5.50 cM. The QTLs for 2-propenyl glucosinolates (GSLs) colocalized with the QTLs for 3-butenyl GSLs between At1g26180 and BnapPIP1580 on LG08 in the field experiments of 2016 and 2017. These QTLs accounted for an average of 42.3% and 42.6% phenotypic variation for 2-propenyl and 3-butenyl GSLs, respectively. Furthermore, the Illumina RNA-sequencing technique was used to excavate the genes responsible for the synthesis of GSLs in the siliques of the parental lines of the RIL mapping population, because the bulk of the seed GSLs might originate from the siliques. Comparative analysis and annotation by gene ontology (GO) and kyoto encyclopedia of genes and genomes (KEGG) revealed that 324 genes were involved in GSL metabolism, among which only 24 transcripts were differentially expressed genes (DEGs). Among those DEGs, 15 genes were involved in the biosynthesis and transport of aliphatic GSLs, and their expression patterns were further validated by qRT-PCR analysis. Joint QTL mapping and RNA-sequencing analyses reveal one candidate gene of IIL1 (LOC106416451) for GSL metabolism in B. juncea. These results will be helpful for further fine mapping, gene cloning and genetic mechanisms of 2-propenyl and 3-butenyl GSLs in B. juncea

Mapping QTLs controlling C18∶3 content.

<p>A. The QTL in Sal02 was located between BnapPIP685 and BnapPIP881 in Y1127×Y1035 and Y1127×Y514. B. The QTL in Sal10 was located between BnapPIP1012 and BnapPIP363 in Y1127×Y1035, and between BnapPIP1012 and At3g43520 in Y514×Y1035. 1-LOD and 2-LOD supporting intervals of each C18∶3 QTL were marked by thick and thin bars, respectively. The <i>SalFAD3.LA1</i> and <i>SalFAD3.LA2</i> genes co-localized with their C18∶3 QTL peaks in the linkage groups Sal02 and Sal10.</p

Linolenic acid contents of the parental lines Y1127, Y514, Y1035 and F₁ seeds, and the mid-parental value in yellow mustard.

<p>*: Linolenic acid content is expressed as mean value ± standard deviation.</p

Frequency distributions of linolenic acid contents in individual seeds of Y1127, Y1035, F₁, (Y1127×Y1035)×Y1035 and F₂ populations.

<p>Frequency distributions of linolenic acid contents in individual seeds of Y1127, Y1035, F₁, (Y1127×Y1035)×Y1035 and F₂ populations.</p