Abstract Detail



Hybrids and Hybridization

Quintana, Isadora [1], Turchetto, Caroline [1], Costa Teixeira, Marcelo [1].

Geometric morphometric analyses in Nicotiana Alatae section in South Brazil.

Diversity of flowers is one of the most striking features of angiosperm radiation. Flowers vary in color, shape, and fragrance pattern, which alone or combined can perform as signals to attract pollinating animals. Members of the Nicotiana genus (Solanaceae) present remarkable diversity in terms of floral and vegetative morphology. Hybridization and shifts in pollinators vectors are cited as important drivers to diversification in this genus. Section Alatae of Nicotiana groups eight species found in southern South America, in different habitats and with different distribution patterns. This section forms a monophyletic group associated with chromosome number n=9 and n=10. The greatest diversity of the section is located in the region of South Brazilian Plateau, where occurs widespread species, as N. alata, N. langsdorfii and N. bonariensis; and also endemic and narrowly distributed species, such as N. mutabilis, N. forgetiana and the possible new species called “rastroensis”. Even though it is possible to intercross these species in experimental conditions, natural hybrids haven’t been registered in this section yet. Therefore, this study aims to investigate the evolutionary mechanisms of the genus Nicotiana section Alatae, identifying the phenotypic variations at the populational level employing geometric morphometric analyses. For this, we collected photographic images of flowers, in lateral and frontal view, in the field. We sampled the entire geographic distribution known for N. forgetiana, including the geographic region of “rastroensis”. We also sampled the population of N. alata in this region and two populations with floral morphology suggestive of hybrids. In total, we analysed 408 flowers from 22 natural populations. Later on, the geometric morphometry was performed for each individual, and this information was analyzed with Principal Component Analysis (PCA) and Canonical Variation Analysis (CVA). The results available so far showed a geographic pattern in N. forgetiana distribution in frontal view and corolla tube shape. The new species rastroensis presented significant differences in corolla shape. The corolla form probably affects the main pollinator in this species. Moreover, the study identified the occurrence of two natural hybrid populations between N. forgetiana and N. alata, occurring in the edge of distribution of N. forgetiana. The hybrid population presented significant differences in their corolla shape, with the majority of individuals shaping the morphospace with N. fogetiana. These results showed that the evolutionary dynamic of N. forgetiana is more complex than it is known until now. Genomic data will address the evolutionary dynamic in these species in South Brazil.


Related Links:
Leon Levy Native Plant Preserve website


1 - UFRGS, Botany, Avenida Bento Gonçalves, 9500, Porto Alegre, Rio Grande do Sul, 91509-900, Brasil

Keywords:
Nicotiana
Floral shape
hybridization
speciation.

Presentation Type: Poster
Session: P, Hybrids and Hybridization Posters
Location: Virtual/Virtual
Date: Wednesday, July 29th, 2020
Time: 5:00 PM Time and date to be determined
Number: PHH002
Abstract ID:422
Candidate for Awards:None


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