Molecular mapping of QTL and candidate genes governing phytosterol content in winter oilseed rape (Brassica napus) and Indian mustard (Brassica juncea)

植物留醇，也称为植物留醇，包括一组植物留体化合物。它们之所以令人感兴趣，是因为它们在植物生长和发育中起着至关重要的作用，并且作为人类饮食的一部分，它们因其降低血液胆固醇的作用而闻名。油料作物种子中植物甾醇含量很高，其相关性至今仍不清楚。与拟南芥相反，我们对芸苔属植物中控制植物甾醇含量的基因一无所知。在以前的工作中，一个大的遗传。在德国冬油菜（Brassica napus）品种中发现了植物甾醇含量的变化。到目前为止，还没有关于印度芥菜B中总植物甾醇含量或单个组分的信息。Juncea。B的适宜分离加倍单倍体群体。napus和B.已经开发了芥菜的QTL，并将在本项目中用于绘制单个和总种子植物甾醇含量以及其他种子质量性状的QTL。将从祖先物种芜菁（Brassica rapa）、黑芥（Brassica nigra）和甘蓝（Brassica oleracea）中测序具有来自拟南芥的已知序列的植物甾醇生物合成途径的关键候选基因，以开发基因座特异性PCR引物。这些基因座特异性引物将用于对相应双二倍体物种B中的相关等位基因进行测序。napus和B. Juncea。双单倍体群体的亲本之间的等位基因序列差异将用于绘制候选基因。结果将揭示候选基因的位置是否与植物甾醇含量的QTL重叠，以及植物甾醇含量的遗传变异是否与其他种子品质性状的变异相关。

Plant sterols, also called phytosterols, comprise a group of plant steroidal compounds. They are of interest because they play a crucial role in plant growth and development and as part of the human diet they are known for their blood cholesterol-lowering effects. High phytosterol contents occur in seeds of oilseed crops, the relevance of which remains hitherto unknown. In contrast to Arabidopsis nothing is know about the genes governing phytosterol content in Brassica species. In previous work, a large genetic. variation for phytosterol content has been found among German winter oilseed rape (Brassica napus) cultivars. So far no information is available on total phytosterol contents or individual components in Indian mustard B. juncea. Suitable segregating doubled haploid populations of B. napus, and of B. juncea have already been developed and will be used in the present project to map QTL for individual and total seed phytosterol content as well as for other seed quality traits. Key candidate genes of the phytosterol biosynthetic pathway with known sequences from Arabidopsis will be sequenced from the progenitor species Brassica rapa, Brassica nigra and Brassica oleracea to develop locus specific PCR primers. Those locus specific primers will be used to sequence the pertinent alleles in the respective amphidiploid species B. napus and B. juncea. Allelic sequence differences between the parents of the doubled haploid populations will be used to map the candidate genes. Results will reveal if positions of candidate genes overlap with those of QTL for phytosterol content and if genetic variation in phytosterol content is related to variation in other seed quality traits.