Mixing maternal and paternal genomes in embryos is not only responsible for the evolutionary success of sexual reproduction, but is also a cornerstone of plant breeding. However, once an interesting gene combination is obtained, further genetic mixing is problematic. To rapidly fix genetic information, doubled haploid plants can be produced: haploid embryos having solely the genetic information from one parent are allowed to develop, and chromosome doubling generates fully homozygous plants. A powerful path to the production of doubled haploids is based on haploid inducer lines. A simple cross between a haploid inducer line and the line with gene combinations to be fixed will trigger haploid embryo development. However, the exact mechanism behind in planta haploid induction remains an enduring mystery. The recent discoveries of molecular actors triggering haploid induction in the maize crop and the model Arabidopsis thaliana pinpoint an essential role of processes related to gamete development, gamete interactions and genome stability. These findings enabled translation of haploid induction capacity to other crops as well as the use of haploid inducer lines to deliver genome editing machinery into various crop varieties. These recent advances not only hold promise for the next generations of plant breeding strategies, but they also provide a deeper insight into the fundamental bases of sexual reproduction in plants.

在胚胎中混合母本和父本基因组不仅是有性生殖进化成功的原因，而且还是植物育种的基石。然而，一旦获得了有趣的基因组合，进一步的基因混合就成为问题。为了快速固定遗传信息，可以生产双倍的单倍体植物：仅具有来自一个亲本的遗传信息的单倍体胚胎就可以发育，染色体加倍生成完全纯合的植物。产生双倍单倍体的有效途径是基于单倍体诱导物系。单倍体诱导物系和具有固定基因组合的系之间的简单杂交将触发单倍体胚胎发育。然而，在植物单倍体诱导中的确切机制仍然是一个持久的谜。拟南芥精确指出了与配子发育，配子相互作用和基因组稳定性有关的过程的重要作用。这些发现使得能够将单倍体诱导能力转化为其他农作物，并利用单倍体诱导系将基因组编辑机制传递到各种作物品种中。这些最新进展不仅为下一代植物育种策略提供了希望，而且还为植物有性繁殖的基本基础提供了更深刻的见识。