During the Quaternary, Chaco Phytogeographic Domain (Chaco) flora in subtropical South America experienced temperature and humidity fluctuations, primarily driven by wind dynamics, leading to significant shifts in species distribution. The palm is endemic to the Chaco and thrives in areas characterized by a warm-rainy climate and mostly restricted to sandy soils. To investigate the current geographic distribution of suitable habitat for while assessing the significance of soil variables, we employed two distinct algorithms in species distribution modeling (SDM).
View Article and Find Full Text PDFThe lowlands of mid-latitude South America comprise complex temperate ecoregions characterized by a unique biodiversity. However, the processes responsible for shaping its species diversity are still largely unknown. Turnera sidoides subsp.
View Article and Find Full Text PDFTriploids can play an important role in polyploid evolution. However, their frequent sterility is an obstacle for the origin and establishment of neotetraploids. Here we analyzed the microsporogenesis of triploids (x = 7) and the crossability among cytotypes of Turnera sidoides, aiming to test the impact of triploids on the origin and demographic establishment of tetraploids in natural populations.
View Article and Find Full Text PDFTurnera sidoides is an autopolyploid complex of obligate outcrossing perennial herbs. It includes five subspecies and five morphotypes in which diploid to octoploid cytotypes were found. Based on phenetic analyses of the complex and karyotype data of polyploid cytotypes, it has been hypothesized that morphological and chromosome differentiation of T.
View Article and Find Full Text PDFUnderstanding the spatiotemporal distribution of genetic variation and the ways in which this distribution is connected to the ecological context of natural populations is fundamental for understanding the nature and mode of intraspecific and, ultimately, interspecific differentiation. The Petunia axillaris complex is endemic to the grasslands of southern South America and includes three subspecies: P. a.
View Article and Find Full Text PDFTurnera sidoides is a complex of distylous perennial rhizomatous herbs that includes five subspecies. Since polyploidy has played a prominent role within this species (x = 7), ongoing studies in T. sidoides are focused on the understanding of the mechanisms involved in the origin and the establishment of polyploids.
View Article and Find Full Text PDFCytogeographical variability among 564 plants from 26 populations of Turnera sidoides subsp. pinnatifida in mountain ranges of central Argentina was analysed with meiotic chromosome counts and flow cytometry and is described at regional and local scales. Populations were primarily tetraploids (2n = 4x = 28), although diploid (2n = 2x = 14), hexaploid (2n = 2x = 42), and mixed populations of diploids and triploids (2n = 3x = 21) were also found.
View Article and Find Full Text PDFTurnera sidoides, with the most southerly distribution of all Turnera species in America, is a complex of obligately outcrossing perennial herbs. Karyotypes of the five subspecies of T. sidoides (x = 7) are described for the first time utilizing root-tip mitotic metaphases.
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