BACKGROUND Cabbage (Brassica oleracea var. capitata) is popular worldwide for consumption as a leafy vegetable. Premature flowering is triggered by low temperature, and deteriorates quality of cabbage as vegetable. In general, growers prefer late-flowering varieties to assure good quality compact head. Here, we report BoFLC1.C9 as a gene with clear sequence variation between cabbage lines with different flowering times, and proposed as molecular marker to characterize early- and late-flowering cabbage lines. RESULTS We identified sequence variation of 67 bp insertions in intron 2, which were contributed in flowering time variation between two inbred lines through rapid down-regulation of the BoFLC1.C9 gene in early-flowering line compared to late-flowering one upon vernalization. One set of primer 'F7R7' proposed as marker, of which was explained with 83 and 80% of flowering time variation in 141 F2 individuals and 20 commercial lines, respectively. CONCLUSIONS This F7R7 marker could be used as genetic tools to characterize flowering time variation and to select as well to develop early- and late-flowering cabbage cultivars.

中文翻译：

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基于BoFLC1.C9中序列变异的分子标记，用于表征早开花和晚开花的白菜基因型。

背景技术甘蓝菜（Brassica oleracea var.capitata）作为叶类蔬菜在世界范围内流行消费。低温触发过早开花，降低了作为蔬菜的卷心菜的品质。通常，种植者更喜欢晚开花的品种，以确保优质的紧凑型头部。在这里，我们报道BoFLC1.C9是一个在不同开花时间的甘蓝株系之间具有清晰序列变异的基因，并被提议作为表征早开花和晚开花甘蓝株系的分子标记。结果我们确定了内含子2中67 bp插入的序列变异，这是由于两个早交系中BoFLC1.C9基因的快速下调相对于春交后的一个较晚开花，导致两个自交系之间的开花时间变化。建议使用一组引物“ F7R7”作为标记，其中141个F2个体和20个商品系的开花时间变化分别为83％和80％。结论该F7R7标记可以用作遗传工具，以表征开花时间的变化并选择以发展早花和晚花的甘蓝品种。