Abstract Detail

Recent Topics Posters

Andrade, Rosa Elena [1], Montalvo, Jose [1], Segovia, Claudia [2], Jadán Guerrero, Mónica Beatriz [1], Soltis, Douglas [3], Soltis, Pamela [4].

Cytogenetic and molecular insights for taxonomic classification of Polylepis pauta Hieron. and P. sericea Wedd. (Rosaceae) in Ecuador.

Polylepis forests are one of the most vulnerable centers of Andean diversity affected by anthropogenic activity. This genus has been mainly classified and identified through morphological characteristics. In Ecuador, both Polylepis pauta and Polylepis sericea have similar morphological traits, which have hampered a proper taxonomic classification. This is the first study performed in Ecuador that combines cytogenetic and molecular techniques in these two similar species. The seedlings and leaves for both studies were collected in the same three populations: Yanacocha, Mojanda, and Cayambe-Coca National Park. For the cytogenetic study, the chromosomes were counted from meristematic root samples. The results showed two groups, one with 2n = 72 for Cayambe-Coca and Mojanda, and the other 2n = 82 in Yanacocha. The molecular study was performed with 142 individuals and 5 SSRs designed for this genus. Eighteen alleles were detected between the two species. The observed heterozygosity, Ho, in Cayambe-Coca was 0.64, in Yanacocha 0.30, and in Mojanda 0.52. In contrast, the expected heterozygosity, He, was 0.60, 0.51, and 0.58, in all cases higher than Ho. Yanacocha is the most distinct population, consistent with its higher chromosome number; this genetic distinctness could be attributable to selection for specific alleles or potential inbreeding. In the other hand, the values reported in Cayambe-Coca and Mojanda indicates that these populations are outcrossing. Moreover, analyses of genetic differentiation and clustering detected two groups: the first one comprising Cayambe-Coca and Mojanda, and the second only Yanacocha. AMOVA showed that the largest source of variation corresponds to within populations. Through both methods and previous systematic studies, it can be inferred that Cayambe-Coca and Mojanda belongs to P. pauta, and Yanacocha represents P. sericea. This research provides a strong scientific basis to resolve the taxonomic conflict, and these results should be part of future conservation and reforestation strategies involving these threatened tree species.

Broader Impacts:

1 - Escuela Politecnica del Ejercito, Departamento de Ciencias de la Vida, Av. Ruminahui s/n, Sangolqui, PI, Ecuador
2 - University of Florida, Florida Museum of Natural History, Dickinson Hall, Gainesville, FL, 32611, USA
3 - University of Florida, Biology and Florida Museum of Natural History, po box 117800, Gainesville, FL, 32611, USA
4 - University of Florida, Florida Museum of Natural History, PO BOX 117800, Gainesville, FL, 32611-7800, USA

Keywords:
Polylepis pauta
P. sericea
population genetics
cytogenetics
Ecuador.

Presentation Type: Recent Topics Poster
Session: P
Location: Grand Salon A - D/Riverside Hilton
Date: Monday, July 29th, 2013
Time: 5:30 PM
Number: PRT019
Abstract ID:1308
Candidate for Awards:None