Cytogenetic characterization and chromosome evolution of the striking tropical Andean species of Capsicum (Solanaceae)

SCALDAFERRO M A; BARBOZA, G.

PLANT BIOSYSTEMS

TAYLOR & FRANCIS LTD

Lugar: Londres; Año: 2023

1126-3504

Fluorochrome chromosome banding and fluorescent in situ hybridization were used tocytogenetically characterize the striking tropical Andean clade species of Capsicum. An adapteddendrogram of the Capsicum phylogeny is presented, showing taxonomic relationships betweenkaryotypes of the Andean clade species, C. baccatum var. pendulum, C. flexuosum, and the sistergroup Lycianthes. To date, the Andean clade includes nine species: C. dimorphum, C. geminifolium,C. hookerianum, C. lanceolatum, C. longifolium, C. lycianthoides, C. piuranum, C. regale and C.rhomboideum, all displaying 2n = 26. This group is characterized by conspicuous cytogeneticcharacters that are very useful in the identification of their species and allow them to bedistinguished from the other group of species with x = 13 from the Atlantic forest, and definitelyfrom the clades with x = 12. The species of the Andean clade possess relatively short genomes,with one NOR per haploid complement. The distribution of the heterochromatin is mainlysubterminal. A single locus of the 35S and 5S rDNA was found per haploid complement. Thediscovery of three pairs of 5S rDNA sites in C. regale was surprising. The chromosomal featuresof these highland clade species could be considered adaptive characters to their geographicaldistribution.