Clonal propagation is a valuable tool for plant breeders to maintain heterozygous genotypes in crop species that are not amenable to self‐pollination or apomixis. An example is the drought‐tolerant forage and N‐fixing cover crop hairy vetch (Vicia villosa Roth), which primarily outcrosses and is developed into composite cultivars by plant breeders. The ability to obtain clones of desirable genotypes in breeding nurseries would enable the maintenance of heterozygous genotypes for genetic study or the ability to reconstitute a true synthetic cultivar. We developed an efficient method of clonal propagation from stem cuttings to maintain genotypes in a vegetative state for a minimum of 2 yr, even when obtained from flowering parental plants. The long‐term viability of such clones is unknown, however. We determined that hairy vetch, which flowers under long days, exhibits a form of partial flowering where vegetative meristems are maintained during conditions that induce flowering. Clones obtained from flowering parents would resume reproductive growth and eventually senesce if kept in inductive conditions. However, if clones were grown under a continuous 6‐h photoperiod, reproductive development would cease and vegetative growth would resume indefinitely.

中文翻译：

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短光周期下紫v毛插条的根和腋生芽发育和花发育停止

克隆繁殖是植物育种者在不适合自花授粉或无融合生殖的作物物种中保持杂合基因型的宝贵工具。一个例子是耐旱的草料和固氮覆盖的农作物长毛紫etch（Vicia villosa）。Roth），主要杂交，并由植物育种者发展成为复合品种。在育种苗圃中获得所需基因型的克隆的能力将能够维持用于基因研究的杂合基因型，或重构真正的合成品种的能力。我们开发了一种有效的从插条进行克隆繁殖的方法，即使从开花的亲本植物中获得，也能将基因型维持在营养状态至少2年。但是，此类克隆的长期生存能力尚不清楚。我们确定长日开花的有毛v子表现出部分开花的形式，在诱导开花的条件下保持了营养分生组织。如果保持在诱导条件下，从开花亲本获得的克隆将恢复生殖生长并最终衰老。但是，如果克隆在连续6小时的光周期下生长，则生殖发育将停止，而营养生长将无限期恢复。