Bulb onion (Allium cepa L.) is an allogamous diploid (2n = 16) important for its culinary uses, nutritional value, and medicinal benefits. Despite its economic importance, onion yields and bulb quality are declining, emphasizing the need for new and improved strategies for maintaining and enhancing overall crop quality. Development of inbred lines in onion through traditional breeding is often difficult due to its biennial life cycle, inbreeding depression, and comparatively high heterozygosities. Moreover, genetic research in onion has been hampered by large nuclear genome size. In this regard, gynogenic doubled haploids promise several advantages over inbred lines in support of onion breeding programs and genetic studies. These include complete homozygosity in doubled haploid lines, reduced DNA methylation, elimination of deleterious alleles, and amenability to genetic analysis. This review focuses on the application of in vitro gynogenesis for producing doubled haploids in onion. Factors influencing haploid induction, methods for inducing chromosome doubling and ploidy assessment, evaluation of haploid progenies and doubled haploid lines, and features of doubled haploids potentially useful in crop improvement and genetic studies, are discussed. We identify four major limitations to the success and efficiency of in vitro gynogenesis in onion and discuss strategies for mitigating the negative impacts they pose. This review may be useful to research programs producing doubled haploids in onion or other Allium species using in vitro gynogenesis.

鳞茎洋葱（葱L.）是同种异型二倍体（2n = 16），对于其烹饪用途，营养价值和药用价值非常重要。尽管其具有经济重要性，但洋葱的产量和鳞茎质量却在下降，强调需要新的和改进的策略来维持和提高整体作物质量。由于其两年一生的生命周期，近交衰退和相对较高的杂合性，通过传统育种开发洋葱近交系通常很困难。此外，洋葱的遗传研究受到较大的核基因组大小的阻碍。就这一点而言，在双亲单倍体发育方面，在支持洋葱育种计划和遗传研究方面，与自交系相比具有许多优势。这些包括双倍单倍体系的完全纯合性，减少的DNA甲基化，消除有害的等位基因，和遗传分析的能力。这篇综述着重于体外雌激素在洋葱中产生双倍单倍体的应用。讨论了影响单倍体诱导的因素，诱导染色体加倍和倍性评估的方法，单倍体后代和双倍单倍体谱系的评估以及双倍单倍体的特性，这些特性可能对作物改良和遗传研究有用。我们确定了成功的体外妇科生成洋葱的四个主要限制，并讨论了减轻其造成的负面影响的策略。这篇评论可能对研究洋葱或其他产生双倍单倍体的计划很有用 讨论了诱导染色体加倍和倍性评估的方法，单倍体后代和双倍单倍体谱系的评估以及可能对作物改良和遗传研究有用的双倍单倍体的特征。我们确定了成功的体外妇科生成洋葱的四个主要限制，并讨论了减轻其造成的负面影响的策略。这篇评论可能对研究洋葱或其他产生双倍单倍体的计划很有用 讨论了诱导染色体加倍和倍性评估的方法，单倍体后代和双倍单倍体谱系的评估以及可能对作物改良和遗传研究有用的双倍单倍体的特征。我们确定了洋葱体外妇科学的成功和效率的四个主要限制，并讨论了减轻其造成的负面影响的策略。这篇评论可能对研究洋葱或其他产生双倍单倍体的计划很有用葱属种采用体外雌激素发育。