In order to clarify the genetic differentiation and reproductive traits of mixed polyploid populations in Parasenecio kamtschaticus complex, geographical distribution, genetic diversity, and reproductive performance were compared among three intraspecific types composed of two cytotypes and two varieties in Japan. Diploid P. kamtschaticus var. kamtschaticus (2×-kamtschaticus) was distributed at the center of the distribution range, tetraploid P. kamtschaticus var. kamtschaticus (4×-kamtschaticus) existed widely throughout the entire range, and tetraploid P. kamtschaticus var. bulbifera (4×-bulbifera), producing bulbils, was restricted to higher elevations. Genetic structure was analyzed using allozyme markers. The genetic diversity of 4×-kamtschaticus was higher than that of 2×-kamtschaticus, with that of 4×-bulbifera being intermediate. Populations of 4×-bulbifera and 2×-kamtschaticus were genetically discriminable from each other in principle coordinate analysis, and the genetic structure of 4×-kamtschaticus populations largely overlapped with those of the other types. Flower and achene production levels were highest in the 4×-kamtschaticus populations and lowest in the 4×-bulbifera populations. Germination activity of achenes was highest in the 2×-kamtschaticus populations and lowest in the 4×-bulbifera populations. Fruit-set success of 4×-bulbifera decreased with elevation because of a shorter growing season, indicating the importance of vegetative reproduction by bulbils at higher elevations. Unexpectedly, the inbreeding coefficients of the 4×-bulbifera populations were the lowest among the three types. Occasional achene production by outcrossing might maintain the high genetic diversity of the 4×-bulbifera populations. The evolution of polyploidy and subsequent bulbil production might enable P. kamtschaticus to disperse a wider range of environmental conditions.

中文翻译：

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Parasenecio kamtschaticus（千里菊科；菊科）混合多倍体种群的地理分布、遗传多样性和繁殖性状

为了阐明Parasenecio kamtschaticus复合体中混合多倍体种群的遗传分化和繁殖性状，比较了日本由两种细胞型和两种变种组成的三种种内类型之间的地理分布、遗传多样性和繁殖性能。二倍体 P. kamtschaticus var. kamtschaticus (2×-kamtschaticus) 分布在分布范围的中心，四倍体 P. kamtschaticus var. kamtschaticus (4×-kamtschaticus) 在整个范围广泛存在，四倍体 P. kamtschaticus var. bulbifera (4x-bulbifera)，生产球茎，仅限于更高的海拔。使用等位酶标记分析遗传结构。4×-kamtschaticus的遗传多样性高于2×-kamtschaticus，4×-bulbifera的遗传多样性居中。4x-bulbifera和2x-kamtschaticus种群在原理坐标分析上具有遗传可区分性，4x-kamtschaticus种群的遗传结构与其他类型的遗传结构有很大的重叠。花和瘦果产量水平在 4×-kamtschaticus 种群中最高，在 4×-bulbifera 种群中最低。瘦果的萌发活性在 2×-kamtschaticus 种群中最高，在 4×-bulbifera 种群中最低。由于生长季节较短，4x-bulbifera 的坐果成功率随着海拔的升高而降低，这表明在高海拔地区通过球茎进行营养繁殖的重要性。出乎意料的是，4x-bulbifera 种群的近交系数是三种类型中最低的。通过异交偶尔产生瘦果可能保持 4x-bulbifera 种群的高遗传多样性。多倍体的进化和随后的球茎生产可能使 P. kamtschaticus 能够分散更广泛的环境条件。