Key Laboratory of Horticultural Plant Biology (HAU), Ministry of Education, National Centre for Vegetable Improvement (Central China), Huazhong Agricultural University, Wuhan, 430070, China.
Plant Cell Rep. 2013 Nov;32(11):1687-701. doi: 10.1007/s00299-013-1480-8. Epub 2013 Aug 3.
Bacterial wilt resistant somatic hybrids were obtained via protoplast fusion between potato and eggplant and three types of nuclear genomes were identified in the hybrids through GISH and SSR analysis.
Cultivated potato (Solanum tuberosum L.) lacks resistance to bacterial wilt caused by Ralstonia solanacearum. Interspecific symmetric protoplast fusion was conducted to transfer bacterial wilt resistance from eggplant (S. melongena, 2n = 2x = 24) into dihaploid potato (2n = 2x = 24). In total, 34 somatic hybrids were obtained, and of these, 11 rooted and were tested for genome components and resistance to race 1 of R. solanacearum. The hybrids exhibited multiple ploidy levels and contained the dominant nuclear genome from the potato parent. Three types of nuclear genomes were identified in the hybrids through genomic in situ hybridization (GISH) and simple sequence repeat (SSR) analysis, including (1) the potato type of the tetraploids in which eggplant chromosomes could not be detected by GISH but their nuclear DNA was confirmed by SSR, (2) the biased type of the hexaploids in which the chromosome dosage was 2 potato:1 eggplant, and (3) the chromosome translocation type of the mixoploids and aneuploids that was characterized by various rates of translocations of nonhomologous chromosomes. Cytoplasmic genome analysis revealed that mitochondrial DNA of both parents coexisted and/or recombined in most of the hybrids. However, only potato chloroplast DNA was retained in the hybrids speculating a compatibility between cpDNA and nuclear genome of the cell. The pathogen inoculation assay suggested a successful transfer of bacterial wilt resistance from eggplant to the hybrids that provides potential resistance for potato breeding against bacterial wilt. The genome components characterized in present research may explain partially the inheritance behavior of the hybrids which is informative for potato improvement.
通过原生质体融合将马铃薯和茄子融合，获得了抗细菌性萎蔫病的体细胞杂种，并通过 GISH 和 SSR 分析鉴定了杂种中的三种核基因组类型。
栽培马铃薯（Solanum tuberosum L.）缺乏对由 Ralstonia solanacearum 引起的细菌性萎蔫病的抗性。通过种间对称原生质体融合将茄子（S. melongena，2n = 2x = 24）的细菌性萎蔫病抗性转移到二倍体马铃薯（2n = 2x = 24）中。总共获得了 34 个体细胞杂种，其中 11 个生根，并对其基因组成分和对 R. solanacearum 1 号菌株的抗性进行了测试。杂种表现出多种倍性水平，并含有马铃薯亲本的显性核基因组。通过基因组原位杂交（GISH）和简单序列重复（SSR）分析，在杂种中鉴定出三种核基因组类型，包括（1）不能通过 GISH 检测到茄子染色体但通过 SSR 确认其核 DNA 的四倍体的马铃薯型，（2）二倍体：1 倍体茄子的偏二倍体的偏二倍体型，（3）染色体易位型的混倍体和非同源染色体易位率不同的染色体非整倍体型。细胞质基因组分析表明，大多数杂种中同时存在父母本的线粒体 DNA 并发生重组。然而，只有马铃薯质体 DNA 保留在杂种中，推测 cpDNA 与细胞核基因组之间存在兼容性。病原菌接种试验表明，茄子的细菌性萎蔫病抗性成功转移到杂种中，为马铃薯抗细菌性萎蔫病的育种提供了潜在抗性。本研究中鉴定的基因组成分部分解释了杂种的遗传行为，这对马铃薯改良具有重要意义。
