Abstract Detail

Population Genetics/Genomics

Lopes , Juliana [1], Mavrodiev, Evgeny [2], Carvalho, Humberto Henrique [1], Zorzatto, Cristiane [1], Azevedo, Ana Luisa [3], Machado, Marco Antonio [3], Gitzendanner, Matt [4], Soltis, Douglas [5], Soltis, Pamela S. [6], Viccini, Lyderson [1].

Genetic Relationships and Polyploid Origins in The Lippia alba polyploid complex (Mill.) N.E. Brown (Verbenaceae).

Plant genomes vary in size and complexity, due in part to polyploidization. Latitudinal analyses of polyploidy are biased towards floras of temperate regions, with much less research done in the tropics. Lippia alba exhibits many chemical and morphological types as well as large phenotypic and genomic plasticity across its geographic range in Brazil. The species has been described as a tropical polyploid complex with diploids, triploids, tetraploids, and hexaploid. However, no data regarding relationships among the ploidal levels and their possible origin has been reported. Our goals are to clarify the relationships among accessions of Lippia alba and the origins of each ploidal level. We investigated 98 samples representing all five geographical regions of Brazil and all ploidal levels using microsatellite and DNA sequences of ITS, trnL-F, and PHOT. The genetic distance was estimated using Jaccard and Dice coefficients based on Unweighted Pair Group Method with Arithmetic Means (UPGMA). A genetic structure analysis was estimated from the allele sizes by Structure software. The sequences of ITS, TrnLF and PHOT genes were automatically aligned using MAFFT. Conserved blocks from the alignments regions were selected with Gblocks as implemented in program Phylogeny.fr. The pattern of the alignment was visually identified. Genetic distance analysis and gene sequence data show that accessions grouped by ploidal level. Comparing microsatellites information and the DNA sequence alignments it is possible to identify some recurrent groups. The triploids form a well-defined group that originated from a single group of diploids. The tetraploids are not closely related to any other accessions, and their origin is unclear. The tetraploids and hexaploid grouped together in SSR and trnL-F analyses, suggesting the contribution of tetraploids to the hexaploid origin. The recovered groups is in accordance with chemical and morphologic data. Only one origin of triploids from a single group of diploids was observed. This framework reveals linkages among the ploidal levels, providing new insights into the evolution of polyploid complexes from the tropics. Financial support: Capes, Fapemig, CNPq

1 - Federal University of Juiz de Fora, Department of Biology, Rua José Lourenço Kelmer, Martelos, Juiz de Fora, MG, 36036-240, Brazil
2 - Florida Natural History Museum, Florida Museum Of Natural History PO Box 117800, Gainesville, FL, 32611, United States
3 - Embrapa Dairy Cattle Research Center, Eugênio do Nascimento Avenue, 610, Aeroporto, Juiz de Fora, MG, 36038-330, Brazil
4 - University Of Florida, Florida Museum Of Natural History, Po Box 117800, Gainsville, FL, 32611, United States
5 - Florida Museum of Natural History, University of Florida, 1659 Museum Road, Gainesville, Florida, 32611, United States
6 - Florida Museum of Natural History, University of Florida, 1659 Museum Road, Gainesville, Florida, 32611, United States

Keywords:
Lippia alba
microsatellites
nuclear genes
plastid genes
Polyploid
Verbenaceae.

Presentation Type: Poster
Session: P, Population Genetics/Genomics
Location: Grand Ballroom - Exhibit Hall/Mayo Civic Center
Date: Monday, July 23rd, 2018
Time: 5:30 PM This poster will be presented at 6:15 pm. The Poster Session runs from 5:30 pm to 7:00 pm. Posters with odd poster numbers are presented at 5:30 pm, and posters with even poster numbers are presented at 6:15 pm.
Number: PPG010
Abstract ID:852
Candidate for Awards:None