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1.
Front Plant Sci ; 12: 770556, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34675959

RESUMO

[This corrects the article DOI: 10.3389/fpls.2020.581513.].

2.
An Acad Bras Cienc ; 93(suppl 3): e20201881, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34550205

RESUMO

Studies concerning the cytogenetics of Gleicheniaceae have been scarce, especially those employing evolutionary approaches. Two chromosome number evolutionary models have been hypothesized for Gleicheniaceae. One proposes that ancestral haploid numbers were small and that the chromosome numbers of extant species evolved through polyploidy. The other model proposes that, at the genus level, fern chromosome evolution occurred from ancestors with essentially the same high chromosome numbers seen in living lineages. Neither of those hypotheses has been tested based on phylogenetic frameworks. We sought to (i) present the state of the art of Gleicheniaceae chromosome numbers; (ii) test the two evolutionary models of chromosome numbers within a phylogenetic framework; (iii) test correlations between DNA contents and chromosome numbers in the family. We report here DNA C-values for five species, which increases the number of investigated taxa nearly twofold and report two new genera records. Ancestral state chromosome reconstruction corroborates the hypothesis that ancestral chromosome numbers in Gleicheniaceae were as high as those of extant lineages. Our results demonstrate the possible role of dysploidy in the evolutionary chromosome history of Gleicheniaceae at the genus level and suggest that the relationship between chromosome number and DNA content does not appear to be linear.


Assuntos
Gleiquênias , Cromossomos de Plantas/genética , Análise Citogenética , Evolução Molecular , Gleiquênias/genética , Filogenia
3.
Front Plant Sci ; 11: 581513, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33519842

RESUMO

Dicranopteris is an ancient and widespread genus of ferns in pantropical regions. Some species of the genus can form dense thickets, and dominate the understory, which are common and key species in tropical and subtropical ecosystems. However, they were mostly cut or burned in forest management because of forming dense thickets which were considered to interfere with forest regeneration and succession. In the current review, we argue that the Dicranopteris species which are able to rapidly colonize barren areas may contribute to ecosystem recovery, resistance to environmental stress, and succession control. Rapid colonization involves prolific spore production, rapid clonal growth, the generation of high surface cover, and the ability to fill gaps; stress resistance includes resistance to abiotic stress, and the ability to reduce soil erosion from rainfall, alien species invasion, and soil contamination and toxicity; and succession facilitation consists of carbon and nutrient sequestration in soil, moderation of the microclimate, alteration of the soil microbial and faunal communities, and determination of which plant species to be established in the next successional stage. All of these ecosystem functions may be beneficial to ecosystem resilience. We expect that the distribution of Dicranopteris will expand in response to global warming, changes in precipitation patterns, increases in soil pollution, deforestation, and land degradation. We recommend that Dicranopteris, as a pioneer fern and a valuable component of tropical and subtropical ecosystems, needs more attention in future research and better management practices to promote forest regeneration and succession.

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