DNA Contents and Karyotypes of the Natural Hybrids in Taraxacum (asteraceae) in Japan

The DNA content and karyotype of the native Japanese Taraxacum platycarpum subsp. hondoense and members of the T. officinale complex are reported. Members of the T. officinale complex were easily distinguished from each other by their DNA content and karyotype. The Japanese diploid Taraxacum and the exotic triploid T. officinale, are distinct in chromosome number, chromosome size, and the number, size and morphology of satellite chromosomes. The karyotypes of the 3x and 4x hybrids are invariably contain one large Japanese Taraxacum chromosome set and two or three small T. officinale chromosome sets, suggesting that the native Japanese species, as the haploid ovule donor (with the Japanese chloroplast DNA haplotype), hybridized asymmetrically with the (reduced) 2x or (unreduced) 3x pollens of the introduced T. officinale.