Buckwheat has open-flower morphology; therefore, isolation is necessary to propagate even in self-pollinating lines. Here, we developed a self-pollinating closed flower breeding line ‘CFK1’ by crossing between closed-flowering individual and self-pollinating breeding line. Progeny analysis suggested that the closed-flowering trait would be dominated by double recessive gene, which we named closed-flowering A and B (cfA and cfB). The evaluation test of outcrossing rate in the field revealed that ‘CFK1’ had 0% in progeny. An a histochemical investigation of flower buds morphology using scanning electron microscope revealed that the petals of ‘CFK1’ were tightly adhered to other petals whereas completely separated in wild type. The agronomic characteristics were evaluated by performance test. Compared to leading variety ‘Shinanonatsusoba’, the ‘CFK1’ had lower plant height, total weight, grain yield and 1-L weight whereas higher plant height, total weight, grain yield and 1-L weight when compared to ‘IH3’. The preharvest-sprouting resistance of ‘CFK1’ is slightly stronger than that of other tested buckwheat. From these results, ‘CFK1’ is promising self-pollinating breeding line that is resistant for outcrossing.

中文翻译：

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荞麦闭花性自花授粉育种系的开发

荞麦具有开放花形态；因此，即使在自花授粉线中传播也需要隔离。在这里，我们通过在闭花个体和自花授粉育种系之间杂交开发了自花闭花育种系“CFK1”。后代分析表明闭花性状将由双隐性基因主导，我们将其命名为闭花A和B（cfA和cfB）。田间异交率评价试验表明'CFK1'的后代为0%。使用扫描电子显微镜对花蕾形态进行的组织化学研究表明，'CFK1' 的花瓣与其他花瓣紧密贴合，而在野生型中则完全分离。通过性能试验评价农艺性状。与领先品种 'Shinanonatsusoba' 相比，'CFK1' 的株高、总重、谷物产量和 1-L 重量较低，而与 'IH3' 相比，其株高、总重量、谷物产量和 1-L 重量较高。'CFK1'的收获前萌芽抗性略强于其他测试荞麦。从这些结果来看，'CFK1' 是一种很有前途的自花授粉育种系，它对异交具有抗性。