Graduate School of Life and Environmental Sciences, Osaka Prefecture University, Sakai, Osaka, 599-8531, Japan.
NARO Hokkaido Agricultural Research Center, Memuro Research Station, 9-4 Shinsei-minami, Memuro, Kasai, Hokkaido, 082-0081, Japan.
Sci Rep. 2021 Aug 24;11(1):17093. doi: 10.1038/s41598-021-96482-6.
Hybrid lethality, meaning the death of F hybrid seedlings, has been observed in many plant species, including Nicotiana. Previously, we have revealed that hybrids of the selected Nicotiana occidentalis accession and N. tabacum, an allotetraploid with S and T genomes, exhibited lethality characterized by the fading of shoot color. The lethality was suggested to be controlled by alleles of loci on the S and T genomes derived from N. sylvestris and N. tomentosiformis, respectively. Here, we extended the analysis of hybrid lethality using other two accessions of N. occidentalis identified from the five tested accessions. The two accessions were crossed with N. tabacum and its two progenitors, N. sylvestris and N. tomentosiformis. After crosses with N. tabacum, the two N. occidentalis accessions yielded inviable hybrid seedlings whose lethality was characterized by the fading of shoot color, but only the T genome of N. tabacum was responsible for hybrid lethality. Genetic analysis indicated that first-mentioned N. occidentalis accession carries a single gene causing hybrid lethality by allelic interaction with the S genome.
杂种致死性，即在许多植物物种中观察到的 F 杂种幼苗死亡，已在包括烟草在内的许多植物物种中得到证实。此前，我们发现，从选定的西烟草品系和 S 和 T 基因组的异源四倍体烟草中选择的杂种表现出以芽色褪色为特征的致死性。这种致死性被认为是由分别来自野烟草和绒毛烟草的 S 和 T 基因组上的等位基因控制的。在这里，我们使用从五个测试品系中鉴定出的另外两个西烟草品系扩展了对杂种致死性的分析。这两个品系与烟草及其两个亲本野烟草和绒毛烟草进行了杂交。与烟草杂交后，这两个西烟草品系产生了不育的杂种幼苗，其致死性表现为芽色褪色，但只有烟草的 T 基因组负责杂种致死性。遗传分析表明，第一个西烟草品系携带一个单一的基因，通过与 S 基因组的等位基因相互作用导致杂种致死性。
