The doubled haploid technique aims to generate pure inbred lines for basic research and as commercial cultivars. The doubled haploid technique first generates haploid plants and is followed by chromosome doubling, which can be separated in time or overlapped, depending the procedure for each species. For a long time, much effort has been focused on haploid production via androgenesis, gynogenesis, or parthenogenesis. The obtention of haploid plants has frequently required more optimization and has lagged behind research and improvements in chromosome doubling methods. Nevertheless, chromosome doubling has recently been of renewed interest to increase the rates and efficiency of doubled haploid plant production through trialing and optimizing of different procedures. New antimitotic compounds and application methods are being studied to ensure the success of chromosome doubling once haploid material has been regenerated. Moreover, a haploid inducer-mediated CRISPR/Cas9 genome-editing system is a breakthrough method in the production of haploid plant material and could be of great importance for species where traditional haploid regeneration methods have not been successful, or for recalcitrant species. In all cases, the new deployment of this system will demand a suitable chromosome doubling protocol. In this review, we explore the existing doubled haploid and chromosome doubling methods to identify opportunities to enhance the breeding process in major crops.

双倍单倍体技术旨在产生纯种自交系，用于基础研究和作为商业品种。双重单倍体技术首先产生单倍体植物，然后是染色体加倍，这可以在时间上分离或重叠，具体取决于每种物种的程序。长期以来，人们一直致力于通过雄激素生成，雌激素生成或孤雌生殖产生单倍体。单倍体植物的获得常常需要更多的优化，并且落后于染色体倍增方法的研究和改进。然而，通过尝试和优化不同的程序，染色体倍增最近引起了人们的兴趣，以提高单倍体单倍植物产量和效率。正在研究新的抗有丝分裂化合物和应用方法，以确保单倍体材料再生后染色体倍增成功。此外，单倍体诱导物介导的CRISPR / Cas9基因组编辑系统是单倍体植物材料生产中的突破性方法，对于传统单倍体再生方法未成功的物种或顽calc物种可能具有重要意义。在所有情况下，该系统的新部署都需要合适的染色体倍增协议。在这篇综述中，我们探索了现有的双倍单倍体和染色体加倍方法，以发现增强主要作物育种过程的机会。单倍体诱导物介导的CRISPR / Cas9基因组编辑系统是单倍体植物材料生产中的突破性方法，对于传统单倍体再生方法尚未成功的物种或顽固物种可能具有重要意义。在所有情况下，该系统的新部署都需要合适的染色体倍增协议。在这篇综述中，我们探索了现有的双倍单倍体和染色体加倍方法，以发现增强主要作物育种过程的机会。单倍体诱导物介导的CRISPR / Cas9基因组编辑系统是单倍体植物材料生产中的突破性方法，对于传统单倍体再生方法尚未成功的物种或顽固物种可能具有重要意义。在所有情况下，该系统的新部署都需要合适的染色体倍增协议。在这篇综述中，我们探索了现有的双倍单倍体和染色体加倍方法，以发现增强主要作物育种过程的机会。