芥菜型油菜脂肪酸含量的变异、相关性分析及芥酸调控基因FAE1特异引物设计

芥菜型油菜是我国芸苔属的三大油料作物之一,具有耐旱、抗病虫等优良特性;而我国是芥菜型油菜的重要起源中心,具有丰富的种质资源.该研究从全国各地搜集了34份芥菜型油菜,在贵阳环境条件下种植,其脂肪酸含量(芥酸、油酸、硬脂酸、亚麻酸和亚油酸)表现出丰富的变异,并呈正态分布.结果表明:这些芥菜型油菜种质资源的不同脂肪酸含量间的相关性发现,芥酸和油酸间呈极显著负相关,亚麻酸和硬脂酸呈极显著的正相关,亚麻酸和亚油酸呈现负相关.利用这些材料的脂肪酸含量进行主成分分析,发现绝大部分材料(30份,占88.2%)集中在二维图的特定区域,只有少数其它材料散落在图中其它区域,他们分别是SL63、棱角油菜、T6342和长阳黄芥,这些变异较大的材料在芥菜型油菜的育种中可以发挥特殊作用.此外,运用来自甘蓝型油菜和甘蓝的芥酸调控基因FAE1的已知序列,并设计了FAE1特异引物,而引物在全部34份芥菜型油菜种质资源中均表现出了较好的扩增效果.因此证实芥菜型油菜中至少含有一个FAE1拷贝.该研究结果对于芥菜型油菜育种在我国的开展及其未来的分子育种具有重要的指导意义.

Variation of fatty acids of Brassica juncea germplasm, correlation analysis and design of specific primer of FAE1 gene for the control of erucic acid

Brassica juncea(AABB, 2n=36)is one of the 3rd Brassica oil rape(the other two oil rapes are: B. rapa and B. napus)in China, the species has many desirable traits, such as strong drought resistance and strong resistance to disease and pest. As the important origin of B. juncea worldwide, China has rich valuable germplasm resources. In this study, we collected 34 B. juncea accessions from all over China, and planted all these accessions with three randomalized replications in Guiyang environment. The fatty acids, including erucic acid, oleic acid, linolenic acid, linoleic acid and stearic acid, was detected by NIR method in this study. All the detected fatty acids showed quantitative and normal distribution in Guiyang environment. Furthermore, we analyzed the correlations among the five above detected fatty acids, the erucic acid and oleic acid are significantly negatively correlated, the linolenic acid and stearic acid are significantly negative correlated, the linolenic acid and linoleic acid are negative correlated. To classify the 34 accessions for better utilization in B. juncea breeding, the principal component analysis(PCA)was used and the results indicated that most of the 34 accessions(30 accessions, about 88.2%)located on one same area, only several other accessions, that was SL63, Lengjiao YC, T6342 and Changyanghuangjie, located on the separate areas. These scattered accessions had special values in B. juncea breeding for their very different traits when comparied with the other accessions. Besides, we BLAST two FAE1 gene sequences in NCBI website from B. napus (AACC, 2n=38)and B. oleracea (CC, 2n=18), respectively, which were further used for designing specific primer for FAE1 gene, responsible for the regulation of erucic acid in Brassica species. The primer showed a good amplyfication in the all the 34 B. juncea accessions. So, this study proves that the B. juncea genome contains at least one FAE1 copy. In conclusion, the study detected the fatty acid content of 34 B. juncea accessions in Guiyang environment and also provides the useful FAE1 primer for the future gene clone in B. juncea, all of which are valuble in the future B. juncea molecular breeding of China.