Karyotype and genome size in Adonis vernalis and Adonis volgensis

The comparative karyological analysis of Adonis vernalis and Adonis volgensis (Ranunculaceae) from 11 populations from Russia (Altai Territory, Novosibirsk Region, Republic of Khakassia) and Bulgaria was carried out. The somatic chromosome number was 2n = 16 in all studied plants. Chromosome sets of A. vernalis from the Altai Territory (near Sibirskiye Ogni village) and the Republic of Khakassia (Tashtipskiy District), A. volgensis from the Altai Territory (near Chernopyatovo village) and Bulgaria (Kavarna Municipality) consist of eight metacentric and eight submetacentric chromosomes. Two pairs of submetacentric chromosomes had small satellites in short arms. The karyotype formula of these plants was 2n = 2x = 16 = 8m + 4sm + 4smsat. The specimen with the chromosome rearrangement (nonreciprocal translocation) was found in the Altai Territory population. The chromosome mutation has changed the chromosome morphology of submetacentric pair to metacentric pair of different size. The karyotype formula of this specimen was 2n = 2x = 16 = 2n = 10m + 6sm. A similar mutation was previously found out in A. apennina (A. sibirica) from the Tomsk Region. The nuclear DNA content (2C-value) was determined in eight Adonis populations by flow cytometry. The average absolute nuclear DNA content in A. vernalis attained on from 18.88 ± 1.01 to 19.47 ± 1.17 pg, and in A. volgensis attained on from 16.10 ± 0.41 to 16.47 ± 0.47 pg. Differences in 2C-value between A. volgensis and A. vernalis correlated with differences in total chromosome lengths of the set.