Geographic patterns and environmental drivers of flower and leaf trait variation in Anarthrophyllum desideratum, an endemic species of Southern Patagonia.

PAIARO, V.; OLIVA, G; COCUCCI, A.A.; SERSIC A.N.

PLANT ECOLOGY & DIVERSITY

TAYLOR & FRANCIS LTD

Lugar: Londres; Año: 2012 p. 13 - 25

1755-0874

Abstract Background: In widely distributed species, geographic patterns of phenotypic variation can appear in clinal (linear or central-marginal) or mosaic fashion in response to environmental factors. Aim: To assess spatial patterns and possible abiotic drivers of flower and leaf variation in Anarthrophyllum desideratum, an endemic legume that grows along wide environmental gradients in Southern Patagonia. Methods: We measured ten floral and foliar traits from 26 populations distributed along the entire species range. We examined phenotypic variation within and among populations, geographical patterns, relationships with climatic and edaphic factors and spatial co-variation between flowers and leaves using uni- and multivariate analyses. Results: Most studied traits showed a higher variability among than within populations. Within-population variability was not associated with population size. Mostly phenotypic differences among populations were structured by geographic distances. Clinal variation patterns, mainly central-marginal, were detected along the SW-NE gradient. Flower and leaf size covaried across populations, whereas overall phenotypes were only weakly coupled. Phenotypic variation was associated with temperature and potassium soil content. Conclusions: Our results support geographically structured patterns of phenotypic variation and suggest an important role of the abiotic environment shaping both floral and foliar differences among A. desideratum populations. Non-stochastic processes may account for the geographical variation found in this species.