Patterns of chromosomal evolution in the florally diverse Andean clade Iochrominae (Solanaceae).

DEANNA ROCÍO; SMITH STACEY D.; SÄRKINEN TIINA; CHIARINI FRANCO

PERSPECTIVES IN PLANT ECOLOGY EVOLUTION AND SYSTEMATICS

ELSEVIER GMBH

Año: 2018 vol. 35 p. 31 - 31

1433-8319

ochrominae is a largely Andean clade known for its remarkable diversity of floral forms and colors. Although knowledge of chromosomal changes can provide insights into the processes underlying speciation, such data in Iochrominae are scant. We performed cytogenetic analyses to characterize chromosome number and morphology, CMA/DAPI heterochromatic bands, and distribution of rDNA sites in Iochrominae. Ancestral karyotypes were reconstructed on a newly-estimated molecular phylogeny in order to test congruence between karyotype evolution and clade differentiation. We found that, compared with its closest relatives, Iochrominae comprises species with highly symmetrical karyotypes, with no changes in base chromosome number. The common ancestor of Iochrominae was inferred to be a diploid with 2n = 24, with a karyotype with 0?2 submetacentric chromosomes and the rest metacentric, an arm ratio ca. 1.30, one locus of 45S or NORs, and one locus of 5S. Using phylogenetic comparative