Data/hora: 10/06/2024 14:01:36

Provedor de dados: | 74
País: | Brazil
Título: | Cytological and genome size data analyzed in a phylogenetic frame: Evolutionary implications concerning Sisyrinchium taxa (Iridaceae: Iridoideae)
Autores: | Burchardt,Paula; Souza-Chies,Tatiana T.; Chauveau,Olivier; Callegari-Jacques,Sidia M.; Brisolara-Corrêa,Lauís; Inácio,Camila Dellanhese; Eggers,Lilian; Siljak-Yakovlev,Sonja; de Campos,José Marcello Salabert; Kaltchuk-Santos,Eliane.
Data: | 2018-01-01
Ano: | 2018
Palavras-chave: | Ancestral chromosome number; DNA content; Meiotic behavior; Pollen viability; Polyploidy.
Resumo: | Abstract Sisyrinchium is the largest genus of Iridaceae in the Americas and has the greatest amount of cytological data available. This study aimed at investigating how genomes evolved in this genus. Chromosome number, genome size and altitude from species of sect. Viperella were analyzed in a phylogenetic context. Meiotic and pollen analyses were performed to assess reproductive success of natural populations, especially from those polyploid taxa. Character optimizations revealed that the common ancestor of sect. Viperella was probably diploid (2n = 2x =18) with two subsequent polyplodization events. Total DNA content (2C) varied considerably across the phylogeny with larger genomes detected mainly in polyploid species. Altitude also varied across the phylogeny, however no significant relationship was found between DNA content changes and altitude in our data set. All taxa presented regular meiosis and pollen viability (&gt; 87%), except for S. sp. nov. aff. alatum (22.70%), suggesting a recent hybrid origin. Chromosome number is mostly constant within this section and polyploidy is the only source of modification. Although 2C varied considerably among the 20 taxa investigated, the diversity observed cannot be attributed only to polyploidy events because large variations of DNA content were also observed among diploids.
Tipo: | Info:eu-repo/semantics/article
Idioma: | Inglês
Identificador: | http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572018000200288
Editor: | Sociedade Brasileira de Genética
Relação: | 10.1590/1678-4685-gmb-2017-0077
Formato: | text/html
Fonte: | Genetics and Molecular Biology  v.41 n.1 suppl.1 2018
Fonte: | info:eu-repo/semantics/openAccess