PDF(Pubmed)
Abstract：
BACKGROUND: Mulberry (Morus spp.) is an economically important woody plant, which has been used for sericulture (silk farming) for thousands of years. The genetic background of mulberry is complex due to polyploidy and frequent hybridization events.
RESULTS: Comparative genomic in situ hybridization (cGISH) and self-GISH were performed to illustrate the chromosome constitution and genetic relationships of 40 mulberry accessions belonging to 12 species and three varietas in the Morus genus and containing eight different ploidy levels. We identified six homozygous cGISH signal patterns and one heterozygous cGISH signal pattern using four genomic DNA probes. Using cGISH and self-GISH data, we defined five mulberry sections (Notabilis, Nigra, Wittiorum, and Cathayana, all contained only one species; and Alba, which contained seven closely related species and three varietas, was further divided into two subsections) and proposed the genetic relationships among them. Differential cGISH signal patterns detected in section Alba allowed us to refine the genetic relationships among the closely related members of this section.
CONCLUSIONS: We propose that GISH is an efficient tool to investigate the chromosome constitution and genetic relationships in mulberry. The results obtained here can be used to guide outbreeding of heterozygous perennial crops like mulberry.
RESULTS: Comparative genomic in situ hybridization (cGISH) and self-GISH were performed to illustrate the chromosome constitution and genetic relationships of 40 mulberry accessions belonging to 12 species and three varietas in the Morus genus and containing eight different ploidy levels. We identified six homozygous cGISH signal patterns and one heterozygous cGISH signal pattern using four genomic DNA probes. Using cGISH and self-GISH data, we defined five mulberry sections (Notabilis, Nigra, Wittiorum, and Cathayana, all contained only one species; and Alba, which contained seven closely related species and three varietas, was further divided into two subsections) and proposed the genetic relationships among them. Differential cGISH signal patterns detected in section Alba allowed us to refine the genetic relationships among the closely related members of this section.
CONCLUSIONS: We propose that GISH is an efficient tool to investigate the chromosome constitution and genetic relationships in mulberry. The results obtained here can be used to guide outbreeding of heterozygous perennial crops like mulberry.
摘要：
背景：桑树（桑属。)是一种重要的经济木本植物，几千年来一直被用于蚕桑(丝绸养殖)。由于多倍体和频繁的杂交事件，桑树的遗传背景很复杂。
结果：进行了比较基因组原位杂交（cGISH）和自我GISH，以说明40种桑树种质的染色体组成和遗传关系，这些桑树种质属于12种和3种品种，并且包含8种不同的倍性水平。我们使用四个基因组DNA探针鉴定了六个纯合cGISH信号模式和一个杂合cGISH信号模式。使用cGISH和自我GISH数据，我们定义了五个桑树部分(Notabilis，Nigra,Wittiorum,还有Cathayana,都只包含一个物种；阿尔巴，其中包含七个密切相关的物种和三个变种，进一步分为两个小节)，并提出了它们之间的遗传关系。在Alba部分中检测到的差异cGISH信号模式使我们能够完善该部分紧密相关成员之间的遗传关系。
结论：我们建议GISH是研究桑树染色体构成和遗传关系的有效工具。此处获得的结果可用于指导桑树等杂合多年生作物的远交。
结果：进行了比较基因组原位杂交（cGISH）和自我GISH，以说明40种桑树种质的染色体组成和遗传关系，这些桑树种质属于12种和3种品种，并且包含8种不同的倍性水平。我们使用四个基因组DNA探针鉴定了六个纯合cGISH信号模式和一个杂合cGISH信号模式。使用cGISH和自我GISH数据，我们定义了五个桑树部分(Notabilis，Nigra,Wittiorum,还有Cathayana,都只包含一个物种；阿尔巴，其中包含七个密切相关的物种和三个变种，进一步分为两个小节)，并提出了它们之间的遗传关系。在Alba部分中检测到的差异cGISH信号模式使我们能够完善该部分紧密相关成员之间的遗传关系。
结论：我们建议GISH是研究桑树染色体构成和遗传关系的有效工具。此处获得的结果可用于指导桑树等杂合多年生作物的远交。
