Genetic diversity, outcrossing rate, and demographic history along a climatic gradient in the ruderal plant Ruellia nudiflora (Acanthaceae)

Abstract

Revista Mexicana de Biodiversidad 86 (2015) 508-520 Evolution Genetic diversity, outcrossing rate, and demographic history along a climatic gradient in the ruderal plant Ruellia nudiflora (Acanthaceae)Diversidad genética, tasa de entrecruzamiento e historia demográfica a lo largo de un gradiente climático en la planta ruderal Ruellia nudiflora (Acanthaceae) AbstractRuellia nudiflora has shown a high potential to easily invade disturbed areas. Outcrossing rate and genetic structure and diversity in this species were examined along a climatic gradient in the Yucatán Peninsula (Mexico) in order to understand the effects of environmental heterogeneityisolation by environment (IBE) -as well as correlation in herkogamy on genetic structure, diversity, and demographic history in this species. Nine populations were sampled along a temperature-precipitation gradient with marked differences in vegetation, measuring the degree of herkogamy in each sampled plant. To evaluate genetic diversity and structure, amplified fragment length polymorphism (AFLP) markers from 76 plants in these populations were used, while the outcrossing rate was evaluated in 22 genetic families from six populations. All populations had high levels of within-population genetic diversity and high outcrossing rates. Virtually all populations were also undergoing demographic and spatial expansion. The partial Mantel test found a positive correlation between geographic and genetic distance, but none between mean temperature, precipitation, and herkogamy with genetic distance. In this context, R. nudiflora shows incipient evidence of genetic differentiation on a small geographical scale (isolation by distance, IBD) but not along the environmental gradient (IBE). Results suggest that under conditions of constant disturbance, R. nudiflora is able to continuously colonize new areas. All Rights Reserved ResumenRuellia nudiflora ha mostrado un alto potencial para invadir fácilmente áreas perturbadas. Con la finalidad de comprender los efectos de la heterogeneidad ambiental (aislamiento por el ambiente, IBE) y de la correlación en la hercogamia, sobre la diversidad, estructura genética e historia demográfica de esta especie, se examinaron la tasa de entrecruzamiento, la estructura y diversidad genética a lo largo de un gradiente climático en la península de Yucatán (México). Se muestreó un total de 9 poblaciones a lo largo de un gradiente de temperatura-precipitación con marcadas diferencias en la vegetación, en donde además se midió el grado de hercogamia en cada planta. Para evaluar la diversidad y estructura genética, se usaron AFLP's en 76 plantas de estas poblaciones, mientras que la tasa de entrecruzamiento se evaluó en 22 familias genéticas de * Corresponding author.

Population genetic structure and marker–trait associations in East and West African Striga hermonthica with varying phenotypic response to Fusarium oxysporum f. sp. strigae isolates Foxy‐2 and FK3

“…Similar population genetic structure has been described in other outcrossing species with or without a parasitic lifestyle, e.g. Orobanche crenata (Román et al ., 2002), Rheum tanguticum (Hu et al ., 2014) and Ruellia nudiflora (Vargas‐Mendoza et al ., 2015).…”

Intra-Specific Latitudinal Clines in Leaf Carbon, Nitrogen, and Phosphorus and their Underlying Abiotic Correlates in Ruellia Nudiflora

“…Previous research with R . nudiflora has shown that relatively weak evidence of local adaptation to abiotic factors such as soil conditions 24 , and genetic analyses indicate that this species has undergone a recent geographic expansion and that populations in the Yucatan Peninsula are of relatively recent origin 25 . These results suggests that there has not been enough time to foster strong genetic differentiation in plant functional traits and stoichiometry in this species.…”

Life history and past demography maintain genetic structure, outcrossing rate, contemporary pollen gene flow of an understory herb in a highly fragmented rainforest

“…Regardless of fragment size, populations possess private alleles and high genetic diversity ( H e  = 0.61), similar to those of long-lived perennial herbs (Nybom, 2004), but higher compared to other understory Acanthaceae plants [e.gr., Graptophyllum reticularum ( H e  = 0.31), Graptophyllum ilicifolium ( H e  = 0.43) and Ruellia nudiflora ( I  = 0.26) (Shapcott, 2007; Vargas-Mendoza et al, 2015). Effective population size estimates ( N e ) showed that most populations are effectively large, suggesting that habitat fragmentation has not as yet reduced N e enough to detect an impact on genetic diversity.…”