title: The contribution of cytogenetics and flow cytometry for understanding the karyotype evolution in three Dorstenia (Linnaeus, 1753) species (Moraceae).
abstract: Chromosome morphometry and nuclear DNA content are useful data for cytotaxonomy and for understanding the evolutionary history of different taxa. However, the chromosome number is the only karyotype aspect reported for the species of Dorstenia so far. In this study, the nuclear genome size of Dorstenia arifolia (Lamarck, 1786), Dorstenia bonijesu (Carauta & C. Valente, 1983) and Dorstenia elata (Hooker, 1840) was evaluated and their karyotype morphometry accomplished, with the aim of verifying the potential of those parameters to understand evolutionary issues. Mean nuclear 2C value ranged from 2C = 3.49 picograms (pg) for Dorstenia elata to 2C = 5.47 pg for Dorstenia arifolia, a variation of ± 1.98 pg. Even though showing a marked difference in 2C value, the three species exhibited the same 2n = 32. Corroborating the flow cytometry data, differences in chromosome morphology were found among the karyotypes of the species investigated. Based on this and the only phylogeny proposed for Dorstenia thus far, structural rearrangements are related to the karyotype variations among the three species. Besides, the karyological analysis suggests a polyploid origin of the Dorstenia species studied here.
authors.affiliation: Laboratório de Citogenética, Departamento de Biologia, Centro de Ciências Agrárias, Universidade Federal do Espírito Santo. CEP: 29.500-000 Alegre - ES, Brazil.
authors.forename: Paulo Marcos
authors.initials: PM
authors.lastname: Amaral-Silva
authors.affiliation: Laboratório de Citogenética, Departamento de Biologia, Centro de Ciências Agrárias, Universidade Federal do Espírito Santo. CEP: 29.500-000 Alegre - ES, Brazil.
authors.forename: Wellington Ronildo
authors.initials: WR
authors.lastname: Clarindo
authors.affiliation: Laboratório de Botânica, Departamento de Biologia, Centro de Ciências Agrárias, Universidade Federal do Espírito Santo. CEP: 29.500-000 Alegre - ES, Brazil.
authors.forename: Tatiana Tavares
authors.initials: TT
authors.lastname: Carrijo
authors.affiliation: Laboratório de Citogenética e Citometria, Departamento de Biologia Geral, Centro de Ciências Biológicas e da Saúde, Universidade Federal de Viçosa. CEP: 36.570-000 Viçosa - MG, Brazil.
authors.forename: Carlos Roberto
authors.initials: CR
authors.lastname: Carvalho
authors.affiliation: Laboratório de Citogenética, Departamento de Biologia, Centro de Ciências Agrárias, Universidade Federal do Espírito Santo. CEP: 29.500-000 Alegre - ES, Brazil.
authors.forename: Milene Miranda
authors.initials: MM
authors.lastname: Praça-Fontes
keywords: Cytogenetics; chromosome structure; euploidy; flow cytometry; karyotype