Tamaño del genoma en especies del género sudamericano Chrysolaena (Vernonieae: Asteraceae) y su relación con características citogenéticas y ambientales

Gisela M. Via do Pico; Gabriela E. Farco; Danilo Marques

doi:10.30972/bon.3519126

Authors

Gisela M. Via do Pico Instituto de Botánica del Nordeste (UNNE-CONICET), Sargento Cabral 2131, Casilla de Correo 209, CP 3400, Corrientes https://orcid.org/0000-0003-4004-561X
Gabriela E. Farco Facultad de Ciencias Exactas y Naturales y Agrimensura (UNNE), Avenida Libertad 5470 https://orcid.org/0000-0003-2212-1383
Danilo Marques Instituto de Biologia (UFU), Universidade Federal de Uberlândia, Minas Gerais https://orcid.org/0000-0003-2571-9874

DOI:

https://doi.org/10.30972/bon.3519126

Keywords:

Chromosome number, DNA content, 2C value, climatic variables, soil variables

Abstract

Genome size is a species level that often allows taxon delimitation, influences
genetic diversity, and can be related to morphological, ecological, and distribution characteristics.
Chrysolaena H. Rob. (Vernonieae, Asteraceae) is a South American genus, highly cytogenetically
diverse, exhibiting large interspecific and intraspecific chromosomal variation. In this work, the
genome size (2C value) of Chrysolaena species was determined to assess variation among
the different chromosome numbers present in the species, to examine the relationship between
genome size and chromosome numbers, latitude, and environmental variables, and expand
the database for Asteraceae. Linear regression results showed that the 2C value is related to
chromosome number. However, the correlation with latitude and environmental variables is very
low. Evolutionary trends in genome size include both increases and decreases, and polyploidy
is believed to be the main mechanism generating increases in genomic DNA content. The
results of this study constitute an important contribution to the knowledge of genome size in a
representative genus of the Asteraceae family in South America.

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