Evidence of local adaptation and stabilizing selection on quantitative traits in populations of the multipurpose American species Acacia aroma (Fabaceae)

POMETTI C; EWENS M; CIALDELLA AM; J. C. VILARDI; BESSEGA C.; B. O. SAIDMAN

BOTANICAL JOURNAL OF THE LINNEAN SOCIETY

WILEY-BLACKWELL PUBLISHING, INC

Lugar: Londres; Año: 2019 vol. 191 p. 128 - 141

0024-4074

Economically and ecologically important quantitative traits of Acacia aroma are related to life history and the sizeand shape of fruits and leaves. Substantial variation is observed for these traits in natural populations, suggesting apossible genetic basis that could be useful for selection programmes. Our objective was to detect signals of selection on12 phenotypic traits in 170 individuals belonging to seven populations of A. aroma in the Chaco Region of Argentina.Phenotypic traits were compared with molecular markers assessed in the same populations. Here, we search forsignatures of natural selection by comparing quantitative trait variation to neutral genetic variation through the PST?FST test. We further test for differences among populations for the 12 phenotypic traits, an association of phenotypicvariation with environmental variables and geographical distance, and we compare the power of discriminationbetween the phenotypic and AFLP datasets. The PST?FST test suggested directional selection for tree height andstabilizing selection for the remaining traits. Analyses of variance showed significant differentiation for eightphenotypic traits. These results suggest selecting among provenances as a management strategy to improve treeheight (which showed divergent selection), whereas significant genetic gain for the other traits might be obtained byselection within provenances