Karyotype and genome size variation in Delphinium subg. Anthriscifolium (Ranunculaceae)

Abstract

Five taxa of Delphinium subg. Anthriscifolium have been karyologically studied through chromosome counting, chromosomal measurement, and karyotype symmetry. Each taxon that we investigated has a basic chromosome number of x = 8, D. anthriscifolium var. savatieri, D. anthriscifolium var. majus, D. ecalcaratum, and D. callichromum were diploid with 2n = 16, while D. anthriscifolium var. anthriscifolium was tetraploid with 2n = 32. Monoploid chromosome sets of the investigated diploid taxa contained 1 metacentric chromosome, 3 submetacentric chromosomes, and 4 subtelocentric chromosomes. Higher interchromosomal asymmetry (CVCL) was present in D. ecalcaratum and D. callichromum than in other taxa. The highest levels of intrachromosomal asymmetry (MCA) and heterogeneity in centromere position (CVCI) were found in D. anthriscifolium var. majus. Diploid and tetraploid genome sizes varied by 3.02–3.92 pg and 6.04–6.60 pg, respectively. Karyotype and genome size of D. anthriscifolium var. savatieri, D. anthriscifolium var. majus, D. callichromum, and D. ecalcaratum were reported for the first time. Finally, based on cytological and morphological data, the classification of Delphinium anthriscifolium was revised.